US20050158561A1

US20050158561A1 - Weatherable multilayer articles and method for their preparation

Info

Publication number: US20050158561A1
Application number: US10/760,826
Authority: US
Inventors: Hua Wang; Qiwei Lu
Original assignee: General Electric Co
Current assignee: SABIC Global Technologies BV
Priority date: 2004-01-16
Filing date: 2004-01-16
Publication date: 2005-07-21
Also published as: AU2005209150A1; KR20060114000A; JP2007523765A; EP1708878A1; WO2005072958A1; CN1929993A; TW200538281A

Abstract

Disclosed are weatherable multilayer articles comprising (i) a coating layer comprising a block copolyestercarbonate comprising structural units derived from at least one 1,3-dihydroxybenzene and at least one aromatic dicarboxylic acid, (ii) a second layer comprising a polymer comprising carbonate structural units, (iii) a substrate layer comprising a polypropylene, and (iv) at least one adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane, wherein the coating layer is in contiguous contact with the second layer, and the adhesive layer is in contiguous contact with the second layer and the substrate layer. Also disclosed is a method for making the multilayer article.

Description

BACKGROUND OF THE INVENTION

The present invention relates to weatherable multilayer resinous articles and their preparation. More particularly, it relates to multilayer articles comprising a protective block copolyestercarbonate coating, a second layer comprising a polymer comprising carbonate structural units, a substrate, and at least one adhesive layer between the second layer and the substrate.
Various resinous articles have a problem of long term color instability. This causes yellowing of the polymer resin, which in some embodiments detracts from its transparency and attractiveness. Loss of gloss can also be an undesirable long term phenomenon.
Yellowing of polymers is often caused by the action of ultraviolet radiation, which is why such yellowing is frequently designated “photoyellowing”. Numerous means for suppressing photoyellowing have been employed and proposed. Many of these involve incorporation in the polymer of ultraviolet absorbing compounds (UVA's). For the most part, UVA's are low molecular weight compounds and they must be employed at relatively low levels, typically up to 1% by weight, to avoid degradation of the physical properties of the polymer such as impact strength and high temperature properties as reflected in heat distortion temperature. Such levels may be inadequate to afford sufficient protection.
One way of protecting a resinous article against photoyellowing and loss of gloss is to apply a coating of a weatherable second polymer, the term “weatherable” as used herein signifying resistance to such phenomena. Weatherable polymers suitable for this purpose include resorcinol isophthalate/terephthalate copolyarylates. This is the subject of Cohen et al., J. Poly. Sci., Part A-1, 9, 3263-3299 (1971), and certain related U.S. patents of Monsanto Company including U.S. Pat. Nos. 3,444,129, 3,460,961, 3,492,261 and 3,503,779. Commonly owned, U.S. Pat. No. 6,572,956 is directed to weatherable multilayer articles with coating layers comprising structural units derived from a 1,3-dihydroxybenzene organodicarboxylate. Commonly owned, U.S. Pat. No. 6,306,507 is directed to weatherable multilayer articles with coating layers comprising at least one coating layer thereon, said coating layer comprising a thermally stable polymer comprising resorcinol arylate polyester chain members substantially free of anhydride linkages linking at least two mers of the polymer chain, prepared by an interfacial method. Said polymer comprising resorcinol arylate polyester chain members is in some embodiments a copolyestercarbonate.
Weatherable copolyestercarbonates are often used as a coating over a second layer which is a polymeric resin comprising carbonate structural units. A particular problem may arise when the assembly of weatherable polymer and second layer is applied to a substrate resin with second layer adjacent to said substrate. When the substrate is highly non-polar, such as a polypropylene substrate, there is virtually no adhesion between the second layer comprising polar carbonate structural units and said substrate. A problem to be solved, therefore, is to develop a method for preparing weatherable multilayer articles comprising a polypropylene-comprising substrate which are capable of use for such varied purposes as body parts for outdoor vehicles and devices such as automobiles, and which exhibit adequate adhesion between the various layers.

BRIEF DESCRIPTION OF THE INVENTION

The present inventors have discovered multilayer articles with coating layers which provide protection from weathering for underlying layers, and which exhibit excellent adhesion between the various layers. In one of its embodiments the present invention comprises a multilayer article comprising (i) a coating layer comprising a block copolyestercarbonate comprising structural units derived from at least one 1,3-dihydroxybenzene and at least one aromatic dicarboxylic acid, (ii) a second layer comprising a polymer comprising carbonate structural units, (iii) a substrate layer comprising a polypropylene, and (iv) at least one adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane, wherein the coating layer is in contiguous contact with the second layer, and the adhesive layer is in contiguous contact with the second layer and the substrate layer. In another of its embodiments the present invention comprises a method for preparing said multilayer article.
Various other features, aspects, and advantages of the present invention will become more apparent with reference to the following description and appended claims.

DETAILED DESCRIPTION OF THE INVENTION

In the following specification and the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings. The singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not. As used herein the term “layer” is used interchangeably with the terms “film” and “sheet”. The terms “adhesive layer” and “tielayer” are used interchangeably.
The copolyestercarbonate film in the multilayer articles of the present invention comprises at least one block copolyestercarbonate comprising alternating carbonate and arylate blocks. Such block copolyestercarbonates include polymers comprising 1,3-dihydroxybenzene structural units and aromatic dicarboxylic acid structural units of the Formula (I):

- wherein each R¹is independently halogen or C_1-12alkyl, p is 0-3, each R²is independently a divalent organic radical, m is at least 1 and n is at least about 4. In some embodiments n is at least about 10, in other embodiments at least about 20 and in still other embodiments about 30-150. In some embodiments m is at least about 3, in other embodiments at least about 10 and in still other embodiments about 20-200. In other embodiments m is between about 20 and 50. Within the context of the invention “alternating carbonate and arylate blocks” means that the copolyestercarbonates comprise at least one carbonate block and at least one arylate block. In particular embodiments block copolyestercarbonates comprise at least one arylate block and at least two carbonate blocks. In another particular embodiment block copolyestercarbonates comprise an A-B-A architecture with at least one arylate block (“B”) and at least two carbonate blocks (“A”).

The arylate blocks contain structural units comprising 1,3-dihydroxybenzene moieties which may be unsubstituted or substituted. Alkyl substituents, if present, are often straight-chain or branched alkyl groups, and are most often located in the ortho position to both oxygen atoms although other ring locations are contemplated. Suitable C_1-12alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, butyl, iso-butyl, t-butyl, nonyl, decyl, and aryl-substituted alkyl, including benzyl. In some embodiments any alkyl substituent is methyl. Suitable halogen substituents include bromo, chloro, and fluoro. 1,3-Dihydroxybenzene moieties containing a mixture of alkyl and halogen substituents are also suitable. The value for p may be in one embodiment 0-3, in another embodiment 0-2, and in still another embodiment 0-1. In one embodiment a 1,3-dihydroxybenzene moiety is 2-methylresorcinol. In many embodiments a 1,3-dihydroxybenzene moiety is. unsubstituted resorcinol in which p is zero. Polymers containing mixtures of 1,3-dihydroxybenzene moieties, such as a mixture of unsubstituted resorcinol with 2-methylresorcinol are also contemplated.
In the arylate structural units said 1,3-dihydroxybenzene moieties are bound to aromatic dicarboxylic acid moieties which may be monocyclic moieties, such as isophthalate or terephthalate or their halogen-substituted derivatives; or polycyclic moieties, illustrative examples of which include biphenyl dicarboxylate, diphenylether dicarboxylate, diphenylsulfone dicarboxylate, diphenylketone dicarboxylate, diphenylsulfide dicarboxylate, or naphthalenedicarboxylate. In some embodiments polycyclic moieties comprise naphthalene-2,6-dicarboxylate; or mixtures of monocyclic and/or polycyclic aromatic dicarboxylates. In many embodiments the aromatic dicarboxylic acid moieties are isophthalate and/or terephthalate. Either or both of said moieties may be present. In one embodiment both are present in a molar ratio of isophthalate to terephthalate in the range of about 0.20-5.0: 1, while in another embodiment both are present in a molar ratio of isophthalate to terephthalate in the range of about 0.25-4.0:1. When the isophthalate to terephthalate ratio is greater than about 4.0:1, then unacceptable levels of cyclic oligomer may form in some embodiments. When the isophthalate to terephthalate ratio is less than about 0.25:1, then unacceptable levels of insoluble polymer may form in some other embodiments. In some embodiments the molar ratio of isophthalate to terephthalate is about 0.40-2.5:1, and in other embodiments about 0.67-1.5:1.
In various embodiments the arylate block segments in the copolyestercarbonates are substantially free of anhydride linkages linking at least two mers of the polymer chain. Substantially free of anhydride linkages in the present context means that the copolyestercarbonates show decrease in molecular weight in some embodiments of less than 10% and in other embodiments of less than 5% upon heating said copolyestercarbonates at a temperature of about 280-290° C. for five minutes.
In the carbonate blocks of the copolyestercarbonates each R²of Formula (I) is independently an organic radical derived from a dihydroxy compound. For the most part, at least about 60 percent of the total number of R²groups in the polymer are aromatic organic radicals and the balance thereof are aliphatic, alicyclic, or aromatic radicals. Suitable R²radicals include, but are not limited to, m-phenylene, p-phenylene, 4,4′-biphenylene, 4,4′-bi(3,5-dimethyl)phenylene, 2,2-bis(4-phenylene)propane and similar radicals such as those which correspond to the dihydroxy-substituted aromatic hydrocarbons disclosed by name or formula (generic or specific) in U.S. Pat. No. 4,217,438. In some embodiments of the invention dihydroxy compounds include 6-hydroxy-1-(4′-hydroxyphenyl)-1,3,3-trimethylindane, 4,4′-(3,3,5-trimethylcyclohexylidene)diphenol; 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane; 2,2-bis(4-hydroxyphenyl)propane (commonly known as bisphenol-A); 4,4-bis(4-hydroxyphenyl)heptane; 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane; 2,2-bis(4-hydroxy-3-methylphenyl)propane; 2,2-bis(4-hydroxy-3-ethylphenyl)propane; 2,2-bis(4-hydroxy-3-isopropylphenyl)propane; 2,4′-dihydroxydiphenylmethane; bis(2-hydroxyphenyl)methane; bis(4-hydroxy-phenyl)methane; bis(4-hydroxy-5-nitrophenyl)methane; bis(4-hydroxy-2,6-dimethyl-3-methoxyphenyl)methane; 1,1-bis(4-hydroxyphenyl)ethane; 1,1-bis(4-hydroxy-2-chlorophenyl)ethane; 2,2-bis(3-phenyl-4-hydroxyphenyl)-propane; bis(4-hydroxyphenyl)cyclohexylmethane; 2,2-bis(4-hydroxyphenyl)-1-phenylpropane; 3,5,3′,5′-tetrachloro-4,4′-dihydroxyphenyl)propane; 2,4′-dihydroxyphenyl sulfone; 2,6-dihydroxy naphthalene; hydroquinone, resorcinol; C_1-3alkyl-substituted resorcinols. In a particular embodiment the dihydroxy compound comprises bisphenol A.
Suitable dihydroxy compounds also include those containing indane structural units such as represented by the Formula (II), which compound is 3-(4-hydroxyphenyl)-1,1,3-trimethylindan-5-ol, and by the Formula (III), which compound is 1-(4-hydroxyphenyl)-1,3,3-trimethylindan-5-ol:
Included among suitable dihydroxy-substituted aromatic hydrocarbons are the 2,2,2′,2′-tetrahydro-1,1′-spirobi[1H-indene]diols having Formula (IV):

- wherein each R³is independently selected from monovalent hydrocarbon radicals and halogen radicals; each R⁴, R⁵, R⁶, and R⁷is independently C_1-6alkyl; each R⁸and R⁹is independently H or C_1-6alkyl; and each n is independently selected from positive integers having a value of from 0 to 3 inclusive. In a particular embodiment the 2,2,2′,2′-tetrahydro-1,1′-spirobi[1H-indene]-diol is 2,2,2′,2′-tetrahydro-3,3,3,′,3′-tetramethyl-1,1′-spirobi [2H-indene]-6,6′-diol (sometimes know as “SBI”).

The term “alkyl” as used in the various embodiments of the present invention is intended to designate linear alkyl, branched alkyl, aralkyl, cycloalkyl, bicycloalkyl, tricycloalkyl and polycycloalkyl radicals containing carbon and hydrogen atoms, and optionally containing atoms in addition to carbon and hydrogen, for example atoms selected from Groups 15, 16 and 17 of the Periodic Table. Alkyl groups may be saturated or unsaturated, and may comprise, for example, vinyl and allyl. The term “alkyl” also encompasses that alkyl portion of alkoxide groups. In various embodiments normal and branched alkyl radicals are those containing from 1 to about 32 carbon atoms, and include as illustrative non-limiting examples C₁-C₃₂alkyl optionally substituted with one or more groups selected from C₁-C₃₂alkyl, C₃-C₁₅cycloalkyl or aryl; and C₃-C₁₅cycloalkyl optionally substituted with one or more groups selected from C₁-C₃₂alkyl. Some particular illustrative examples comprise methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tertiary-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl and dodecyl. Some illustrative non-limiting examples of cycloalkyl and bicycloalkyl radicals include cyclobutyl, cyclopentyl, cyclohexyl, methylcyclohexyl, cycloheptyl, bicycloheptyl and adamantyl. In various embodiments aralkyl radicals are those containing from 7 to about 14 carbon atoms; these include, but are not limited to, benzyl, phenylbutyl, phenylpropyl, and phenylethyl. In various embodiments aryl radicals used in the various embodiments of the present invention are those substituted or unsubstituted aryl or heteroaryl radicals containing from 6 to 18 ring carbon atoms. Some illustrative non-limiting examples of these aryl radicals include C₆-C₁₅aryl optionally substituted with one or more groups selected from C₁-C₃₂alkyl, C₃-C₁₅cycloalkyl or aryl. Some particular illustrative examples of aryl radicals comprise substituted or unsubstituted phenyl, biphenyl, toluyl and naphthyl. Heteroaryl groups comprise those containing from about 3 to about 10 ring carbon atoms, and include, but are not limited to, triazinyl, pyrimidinyl, pyridinyl, furanyl, thiazolinyl and quinolinyl.
In some embodiments each R²is an aromatic organic radical and in particular embodiments a radical of the Formula (V):
-A¹-Y-A²-, (V)

- wherein each A¹and A²is a monocyclic divalent aryl radical and Y is a bridging radical in which one or two carbon atoms separate A¹and A². The free valence bonds in Formula (V) are usually in the meta or para positions of A¹and A²in relation to Y. Compounds in which R2 has Formula (V) are bisphenols, and for the sake of brevity the term “bisphenol” is sometimes used herein to designate the dihydroxy-substituted aromatic hydrocarbons; it should be understood, however, that non-bisphenol compounds of this type may also be employed as appropriate.

In Formula (V), A1 and A2 typically represent unsubstituted phenylene or substituted derivatives thereof, illustrative substituents (one or more) being alkyl, alkenyl, and halogen (particularly bromine). In many embodiments A1 and A²represent unsubstituted phenylene radicals. Both A1 and A2 may be p-phenylene, although both may be o- or m-phenylene or one o- or m-phenylene and the other p-phenylene.
The bridging radical, Y, is one in which one or two atoms, separate A¹from A². In a particular embodiment one atom separates A¹from A². Illustrative radicals of this type are —C═O, —O—, —S—, —SO— or —SO₂—, methylene, cyclohexylmethylene, 2-[2,2,1]-bicycloheptylmethylene, ethylene, isopropylidene, neopentylidene, cyclohexylidene, cyclopentadecylidene, cyclododecylidene, and adamantylidene. In some embodiments such radicals are gem-alkylene radicals. Also included, however, are unsaturated radicals. For reasons of availability and particular suitability for the purposes of this invention a particular bisphenol is 2,2-bis(4-hydroxyphenyl)propane (hereinafter referred to as bisphenol A or BPA), in which Y is isopropylidene and A¹and A²are each p-phenylene.
Depending upon whether or not any unreacted 1,3-dihydroxybenzene moiety is present in the reaction mixture as described hereinafter, R²in the carbonate blocks may consist of or at least partially comprise a radical derived from a 1,3-dihydroxybenzene moiety. Therefore, in one embodiment of the present invention the copolyestercarbonates comprise carbonate blocks with R²radicals derived from a dihydroxy compound identical to at least one 1,3-dihydroxybenzene moiety in the polyarylate blocks. In another embodiment the copolyestercarbonates comprise carbonate blocks with R²radicals derived from a dihydroxy compound different from any 1,3-dihydroxybenzene moiety in the polyarylate blocks. In yet another embodiment the copolyestercarbonates comprise carbonate blocks containing a mixture of R²radicals derived from dihydroxy compounds at least one of which is the same as and at least one of which is different from any 1,3-dihydroxybenzene moiety in the polyarylate blocks. When a mixture of R²radicals derived from dihydroxy compounds is present, then the molar ratio of dihydroxy compounds identical to those present in the polyarylate blocks to those dihydroxy compounds different from those present in the polyarylate blocks is typically about 1:999 to 999:1. In some particular embodiments the copolyestercarbonates comprise carbonate blocks containing a mixture of R²radicals derived from at least two of unsubstituted resorcinol, a substituted resorcinol, and bisphenol A.
Diblock, triblock, and multiblock copolyestercarbonates are encompassed in the present invention. The chemical linkages between blocks comprising arylate chain members and blocks comprising organic carbonate chain members typically comprise a carbonate linkage between a diphenol residue of an arylate moiety and a C═O)—C— moiety of an organic carbonate moiety, although other types of linkages such as ester and/or anhydride are also possible. A typical carbonate linkage between said blocks is shown in Formula (VI), wherein R¹and p are as previously defined:
In one embodiment the copolyestercarbonate is substantially comprised of a diblock copolymer with a carbonate linkage between an arylate block and an organic carbonate block. In another embodiment the copolyestercarbonate is substantially comprised of a triblock carbonate-ester-carbonate copolymer with carbonate linkages between the arylate block and organic carbonate end-blocks. Copolyestercarbonates with at least one carbonate linkage between an arylate block and an organic carbonate block are typically prepared from 1,3-dihydroxybenzene arylate-containing oligomers containing at least one and often two hydroxy-terminal sites (hereinafter sometimes referred to as hydroxy-terminated polyester intermediate).
In another embodiment the copolyestercarbonate comprises arylate blocks linked by carbonate linkages as shown in Formula (VII):

- wherein R¹, p, and n are as previously defined, and the arylate structural units are as described for Formula (I). Copolyestercarbonates comprising Formula (VII) may arise from reaction of hydroxy-terminated polyester intermediate with a carbonate precursor in the substantial absence of any dihydroxy compound different from the hydroxy-terminated polyester intermediate. In other embodiments the copolyestercarbonate may comprise a mixture of copolyestercarbonates with different structural units and different architectures, for example as described herein.

In the copolyestercarbonates suitable for use in the present invention the distribution of the blocks may be such as to provide a copolymer having any desired weight proportion of arylate blocks in relation to carbonate blocks. The copolyestercarbonates contain in one embodiment about 5% to about 99% by weight arylate blocks; in another embodiment about 20% to about 98% by weight arylate blocks; in another embodiment about 40% to about 98% by weight arylate blocks; in another embodiment about 60% to about 98% by weight arylate blocks; in another embodiment about 80% to about 96% by weight arylate blocks; and in still another embodiment about 85% to about 95% by weight arylate blocks.
The copolyestercarbonate film can comprise other components such art-recognized additives including, but not limited to, stabilizers, color stabilizers, heat stabilizers, light stabilizers, auxiliary UV screeners, auxiliary UV absorbers, flame retardants, anti-drip agents, flow aids, plasticizers, ester interchange inhibitors, antistatic agents, mold release agents, and colorants such as metal flakes, glass flakes and beads, ceramic particles, other polymer particles, dyes and pigments which may be organic, inorganic or organometallic. In a particular embodiment a copolyestercarbonate-comprising layer is substantially transparent.
The thickness of the coating layer is sufficient to provide protection of the underlying layers from weathering, in particular from the effects of UV radiation, as measured, for example, by retention of such properties as gloss and by color stability in any colorant-comprising layer. In one embodiment the thickness of the coating layer is in a range of about 2-2,500 microns, in another embodiment in a range of about 10-250 microns, and in another embodiment in a range of about 50-175 microns.
If desired, an overlayer may be included over the coating layer, for example to provide abrasion or scratch resistance. In a particular embodiment a silicone overlayer is provided over a copolyestercarbonate-comprising coating layer.
Multilayer articles of the present invention comprise a second layer comprising a polymer comprising carbonate structural units. In one embodiment the polymer of the second layer comprises at least one homopolycarbonate. Any polycarbonate capable of being processed into a film or sheet is suitable. In various embodiments suitable polycarbonates comprise those with structural units derived from monomers selected from the group consisting of all those described above for use in the carbonate blocks of the block copolyestercarbonate. In particular embodiments polycarbonate film comprises bisphenol A homo- or copolycarbonates. In another particular embodiment polycarbonate film comprises bisphenol A homopolycarbonate. In other embodiments polycarbonate film comprises a blend of at least one first polycarbonate with at least one other polymeric resin, examples of which include, but are not limited to, a second polycarbonate differing from said first polycarbonate either in structural units or in molecular weight or in both these parameters, or a polyester, or an addition polymer such as acrylonitrile-butadiene-styrene copolymer or acrylonitrile-styrene-acrylate copolymer.
The second layer can comprise other components such as art-recognized additives including, but not limited to, stabilizers, color stabilizers, heat stabilizers, light stabilizers, UV screeners, UV absorbers, flame retardants, anti-drip agents, flow aids, plasticizers, ester interchange inhibitors, antistatic agents, mold release agents, fillers, and colorants such as metal flakes, glass flakes and beads, ceramic particles, other polymer particles, dyes and pigments which may be organic, inorganic or organometallic. In a particular embodiment a second layer further comprises at least one colorant. In another particular embodiment a second layer comprises both a bisphenol A polycarbonate and at least one colorant selected from the group consisting of dyes, pigments, glass flakes, and metal flakes. In a particular embodiment metal flake comprises aluminum flake. In another particular embodiment metal flake comprises aluminum flake which has dimensions of about 20-70 microns. Further examples of colorants include, but are not limited to, Solvent Yellow 93, Solvent Yellow 163, Solvent Yellow 114/Disperse Yellow 54, Solvent Violet 36, Solvent Violet 13, Solvent Red 195, Solvent Red 179, Solvent Red 135, Solvent Orange 60, Solvent Green 3, Solvent Blue 97, Solvent Blue 104, Solvent Blue 104, Solvent Blue 101, Macrolex Yellow E2R, Disperse Yellow 201, Disperse Red 60, Diaresin Red K, Colorplast Red LB, Pigment Yellow 183, Pigment Yellow 138, Pigment Yellow 110, Pigment Violet 29, Pigment Red 209, Pigment Red 209, Pigment Red 202, Pigment Red 178, Pigment Red 149, Pigment Red 122, Pigment Orange 68, Pigment Green 7, Pigment Green 36, Pigment Blue 60, Pigment Blue 15:4, Pigment Blue 15:3, Pigment Yellow 53, Pigment Yellow 184, Pigment Yellow 119, Pigment White 6, Pigment Red 101, Pigment Green 50, Pigment Green 17, Pigment Brown 24, Pigment Blue 29, Pigment Blue 28, Pigment Black 7, Lead Molybdates, Lead Chromates, Cerium Sulfides, Cadmium Sulfoselenide, and Cadmium Sulfide. Illustrative extending and reinforcing fillers include, but are not limited to, silica, silicates, zeolites, titanium dioxide, stone powder, glass fibers or spheres, carbon fibers, carbon black, graphite, calcium carbonate, talc, mica, lithopone, zinc oxide, zirconium silicate, iron oxides, diatomaceous earth, calcium carbonate, magnesium oxide, chromic oxide, zirconium oxide, aluminum oxide, crushed quartz, calcined clay, talc, kaolin, asbestos, cellulose, wood flour, cork, cotton and synthetic textile fibers, especially reinforcing fillers such as glass fibers, carbon fibers, and metal fibers.
The thickness of the second layer is in one embodiment in a range of about 2-2,500 microns, in another embodiment in a range of about 10-1,000 microns, and in another embodiment in a range of about 50-600 microns. An adhesive layer may optionally be present between the copolyestercarbonate-comprising coating layer and the second layer comprising carbonate structural units. In various embodiments said optional adhesive layers comprise those known in the art which provide adhesion to a surface or layer comprising a polymer comprising carbonate structural units. In some embodiments said optional adhesive layer is transparent and in other embodiments said optional adhesive layer has the same color as the second layer.
Suitable substrates in multilayer articles of the invention comprise at least one polymer comprising polypropylene structural units. In the present context the term “polypropylene” refers to polymers comprising structural units derived from propylene, and includes homopolypropylene and copolymers comprising structural units derived from propylene. In some embodiments the polypropylene may be a copolymer having at least about 70 weight percent, or at least about 80 weight percent, or at least about 90 weight percent of structural units derived from polymerization of propylene.
Polypropylene-comprising substrates may comprise either functionalized or unfunctionalized, or a mixture of functionalized and unfunctionalized polypropylene. Illustrative examples of suitable polypropylene-comprising substrates include random, graft, and block copolymers of propylene further comprising up to about 30 weight percent of units derived from C₂-C₁₀alpha-olefins, including aromatic alpha-olefins. In one particular embodiment a suitable alpha-olefin is ethylene. In other embodiments suitable substrates comprise acid- or anhydride-functionalized polypropylene homopolymers or copolymers formed by reaction of a polypropylene homopolymer or a polypropylene-comprising copolymer with at least one polar functionalization agent selected from the group consisting of a vinyl carboxylic acid or anhydride, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, malic acid and monoesters of maleic acid and fumaric acid with monohydric alcohols. It will be understood that in some embodiments both acid and anhydride functionality may exist simultaneously on a polypropylene-comprising substrate. In still other embodiments suitable substrates comprise amine-functionalized polypropylenes formed, for example, by reaction of acid-functionalized and particularly anhydride-functionalized polypropylenes with a functionalization agent comprising at least one primary or secondary amine group, illustrative examples of which comprise alpha, omega alkylenediamines; ethylene diamine, propylene diamine, butylene diamine, hexamethylenediamine; polyoxyalkylene diamines; N-alkyl alpha, omega alkylenediamines; N-alkyl alpha, omega ethylenediamines; N-hexylethylenediamine; bis(alpha-aminoalkyl)aromatics; p-xylylene diamine and m-xylylene diamine. In some embodiments preferred polypropylenes may have a flexural modulus of at least about 100,000 pounds per square inch (689 megapascals) at 23° C. as measured according to ASTM D790. In other embodiments polypropylenes may have a melt flow index of about 0.1 to about 50 g/10 minutes, preferably about 1 to about 30 g/10 minutes when measured according to ASTM DI 238 at 2.16 kg and 200° C. Polypropylene-comprising substrates further comprise blends of the above homopolymers and copolymers. In other embodiments polypropylene-comprising substrates comprise blends of the above homopolymers and copolymers with at least one thermoplastic material. Illustrative examples of suitable thermoplastic materials include, but are not limited to, polyphenylene ether, polyamide, polyester, polyetherimide, polyethylene and polystyrene. In a particular embodiment polypropylene-comprising substrates comprise a mixture of polypropylene homopolymer or copolymer with poly(2,6-dimethyl-1,4-phenylene ether). In another illustrative embodiment a suitable polypropylene-comprising substrate is thermoplastic polyolefin, also known as “TPO”.
In embodiments wherein polypropylene-comprising substrates are homopolypropylenes, then said homopolypropylenes typically have a crystalline content of at least about 20%, preferably at least about 30%. In another embodiment homopolypropylene substrates have a crystallinity content of less than about 90% or less than about 80%.
There is no particular limitation on the thickness of the polypropylene-comprising substrate layer provided that a multilayer article comprising the substrate can be processed into a final desired form. The thickness of the polypropylene-comprising substrate layer is in one embodiment in a range of about 2-12,500 microns, in another embodiment in a range of about 5-10,000 microns, in another embodiment in a range of about 10-6,000 microns, in another embodiment in a range of about 10-2,500 microns, in another embodiment in a range of about 10-1,000 microns, in another embodiment in a range of about 10-600 microns, in another embodiment in a range of about 10-375 microns, in another embodiment in a range of about 20-300 microns, in another embodiment in a range of about 20-250 microns and in another embodiment in a range of about 25-175 microns.
A polypropylene-comprising substrate layer may additionally contain art-recognized additives including, but not limited to, colorants, pigments, dyes, impact modifiers, stabilizers, color stabilizers, heat stabilizers, light stabilizers, UV screeners, UV absorbers, flame retardants, anti-drip agents, fillers, flow aids, plasticizers, ester interchange inhibitors, antistatic agents, and mold release agents. In one embodiment of the invention a polypropylene-comprising substrate also incorporates at least one filler and/or colorant. Illustrative extending and reinforcing fillers, and colorants include silica, silicates, zeolites, titanium dioxide, stone powder, glass fibers or spheres, carbon fibers, carbon black, graphite, calcium carbonate, talc, mica, lithopone, zinc oxide, zirconium silicate, iron oxides, diatomaceous earth, calcium carbonate, magnesium oxide, chromic oxide, zirconium oxide, aluminum oxide, crushed quartz, calcined clay, talc, kaolin, asbestos, cellulose, wood flour, cork, cotton and synthetic textile fibers, especially reinforcing fillers such as glass fibers, carbon fibers, and metal fibers, as well as colorants such as metal flakes, glass flakes and beads, ceramic particles, other polymer particles, dyes and pigments which may be organic, inorganic or organometallic.
Multilayer articles of the invention comprise at least one adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane. In some embodiments of the invention the adhesive layer may optionally comprise a second polypropylene which is not amine-functionalized. In one particular embodiment said second polypropylene comprises any polypropylene suitable for use as the substrate layer. In another particular embodiment said second polypropylene comprises the same polypropylene that is present in the substrate layer.
In the present context amine-functionalized polypropylene refers to either amine-functionalized polypropylene homopolymer or copolymer, or a mixture thereof. Amine-functionalized polypropylene may be derived from, but is not limited to, any polypropylene suitable for use as substrate layer described hereinabove. Amine-functionalized polypropylene may be prepared by any known method of preparation and may comprise either primary amine-functionalized polypropylene, secondary amine-functionalized polypropylene, or both primary and secondary amine-functionalized polypropylene. In one embodiment a suitable amine-functionalized polypropylene may be prepared through reaction between (i) a polypropylene bearing at least one amine-reactive group (sometimes referred to hereinafter as amine-reactive polypropylene) and (ii) at least one amine compound bearing at least two amine groups, both of which may be primary, or both of which may be secondary, or one of which may be primary and one secondary. Although the invention is not limited by any theory of operation, it is believed that statistically a high proportion of only one amine group on said amine compound reacts with polypropylene bearing an amine-reactive group, thus producing a functionalized polypropylene bearing a free amine group. Illustrative polypropylenes bearing an amine-reactive group comprise those which bear at least one functionality selected from the group consisting of acid, ester, and anhydride. In particular embodiments illustrative polypropylenes bearing an amine-reactive group may be derived from reaction of polypropylene in a melt or solid state process with vinyl carboxylic acid or anhydride, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, malic acid or monoesters of maleic acid and fumaric acid with monohydric alcohols. It will be understood that in some embodiments both acid and anhydride functionality may exist simultaneously on a polypropylene bearing an amine-reactive group. An illustrative preparation method for an amine-functionalized polypropylene is given in Q.-W. Lu et al., Macromolecular Symposia, volume 198, pp. 221-232 (2003).
In various embodiments polyurethanes suitable for use comprise thermoplastic polyurethanes known in the art which provide adhesion to a surface or layer comprising a polymer comprising carbonate structural units. Thermoplastic polyurethanes typically comprise structural units derived from polyol chains that are tied together by hard segments derived from at least one organic diisocyanate and at least one optional chain extender. The polyol chains are typically referred to as soft segments which impart low-temperature flexibility and room-temperature elastomeric properties. Generally, the higher the soft segment concentration, the lower will be the modulus, tensile strength, and hardness of the polyurethane, while elongation will increase.
In some embodiments polyols for thermoplastic polyurethanes include, but are not limited to, at least one polyol selected from the group consisting of polyether polyols, polyester polyols and mixtures thereof. In some particular embodiments thermoplastic polyurethanes comprise structural units derived from a substantially linear polyether polyol or polyester polyol and a chain-extender selected from the group consisting of C₂-C₁₀glycols. Illustrative examples of C₂-C₁₀glycol chain-extenders include, but are not limited to, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol; hydroquinone bis-(hydroxyethyl)ether; cyclohexylene diols (1,4-, 1,3-, and 1,2-isomers), isopropylidene bis(cyclohexanols); diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol; ethanolamine, N-methyldiethanolamine, and the like; and mixtures of any of the above. In other particular embodiments thermoplastic polyurethanes comprise structural units derived from at least one of polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol, copolymers of ethylene oxide and propylene oxide, polytetramethylene glycols, and copolymers of tetrahydrofuran and ethylene oxide and/or propylene oxide. Suitable polyether polyols typically have a number average molecular weight of at least 400, preferably at least 1250 and more preferably at least 2,000 but less than 20,000, preferably less than 10,000, and more preferably less than 8,000.
In still other particular embodiments thermoplastic polyurethanes comprise structural units derived from polyester polyols derived from reaction of adipic acid and at least one diol selected from the group consisting of C₂-C₁₀glycols, illustrative examples of which comprise those cited hereinabove. Thermoplastic polyurethanes may also comprise structural units derived from polyester polyols derived from polymerization of eta-caprolactone using an initiator such as ethylene glycol, ethanolamine and the like, and those prepared by esterification of polycarboxylic acids such as phthalic, terephthalic, succinic, glutaric, adipic, azelaic and the like acids with polyhydric alcohols such as ethylene glycol, butanediol, cyclohexanedimethanol and the like.
Typical diisocyanates used to prepare thermoplastic polyurethanes include, but are not limited to, MDI (methylene diphenyl diisocyanate) including the 4,4′-isomer, the 2,4′-isomer and mixtures thereof; hexamethylene diisocyanate, isophorone diisocyanate, methylene bis(cyclohexyl isocyanate) as well as the 4,4′-isomer, 2,4′-isomer and mixtures thereof and all the geometric isomers thereof including trans/trans, cis/trans, cis/cis and mixtures thereof, cyclohexylene diisocyanate, as well as its 1,2-isomer, 1,3-isomer, and 1,4-isomer, 1-methyl-2,5-cyclohexylene diisocyanate, 1-methyl-2,4-cyclohexylene diisocyanate, 1-methyl-2,6-cyclohexylene diisocyanate and 4,4′-isopropylidene bis(cyclohexyl isocyanate), m- and p-phenylene diisocyanates, chlorophenylene diisocyanates, alpha,alpha′-xylylene diisocyanate, 2,4- and 2,6-toluene diisocyanate and the mixtures of these latter two isomers, tolidine diisocyanate, 1,5-naphthalene diisocyanate, 4,4′-diisocyanatodicyclohexyl, and all geometric isomers and mixtures thereof and the like. Also included are the modified forms of MDI. In some embodiments suitable thermoplastic polyurethanes comprise those with degree of hardness in a range of between about 60° Shore A and about 75° Shore D as measured by ASTM D2240 or ISO 868. In other embodiments suitable thermoplastic polyurethanes have a melt flow rate of about 4 to 100, more preferably 10 to 90 g/10 minutes as measured by ASTM D-1238. The thermoplastic polyurethane may optionally comprise at least one filler such as crystalline silica or quartz, or carbon black.
The adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane may be prepared by combining a mixture-comprising amine-functionalized polypropylene and polyurethane under conditions of intimate mixing. In a particular embodiment a mixture comprising amine-functionalized polypropylene and polyurethane may be combined in the melt such as, but not limited to, using an extruder, a kneading apparatus, a roll mill, a high viscosity mixing apparatus and the like. In one particular embodiment the mixture comprising amine-functionalized polypropylene and polyurethane may be combined in a one-step extrusion process by feeding amine-reactive polypropylene and amine compound at the feed throat of the extruder to prepare amine-functionalized polypropylene in the front part of said extruder, followed by optional devolatilization and then feeding of polyurethane to a downstream feed port. In some embodiments of the invention an optional amine quencher may be added following combination of amine-functionalized polypropylene and polyurethane, for example following said optional devolatilization step. Suitable amine quenchers are well-known in the art; illustrative examples include, but are not limited to epoxys, anhydrides, acids, oxazolines and isocyanates.
Although the invention is not limited by any theory of operation, it is believed that free amine groups on amine-functionalized polypropylene may react with urethane linkages or with isocyanate end-groups (arising, for example, from degradation of polyurethane) to form a polypropylene-polyurethane copolymer which acts as a compatibilizer for polypropylene and polyurethane. Thus, in another embodiment of the invention the adhesive layer comprises a polypropylene-polyurethane copolymer. The polypropylene portion of said copolymer is then compatible with a polypropylene-comprising substrate, thus providing suitable adhesion between said multilayer article components. An illustrative preparation method for a compatibilized blend of amine-functionalized polypropylene and polyurethane is given in Q.-W. Lu et al., Macromolecular Symposia, volume 198, pp. 221-232 (2003).
The adhesive layer may also optionally comprise unreacted amine-functionalized polypropylene, or polyurethane or both. In another embodiment of the invention the adhesive layer comprises a compatibilized polypropylene-polyurethane blend, said compatibilization being provided by the reaction product of amine-functionalized polypropylene and polyurethane. Optionally a second polypropylene which is not amine-functionalized may also be present in the adhesive layer. Said second polypropylene may be combined by intimate mixing with amine-functionalized polypropylene and polyurethane either before, during or after intimate mixing of said amine-functionalized polypropylene and polyurethane. In one embodiment a second polypropylene which is not amine-functionalized may be fed along with amine-reactive polypropylene at the feed throat or along with polyurethane at a down-stream feed port, or at both the feed throat and the downstream feed port.
The wt./wt. ratio of polyurethane to amine-functionalized polypropylene is in one embodiment in a range of between about 5:95 and about 98:2. Within this range, the proportion of polyurethane in the adhesive layer is often greater than about 20 wt. %, preferably greater than about 30 wt. % and more preferably greater than about 40 wt. %, based on the weight of the adhesive layer. Also desirable within this range, is an amount of polyurethane which is often less than or equal to about 90 wt. %, preferably less than or equal to about 85 wt. % and more preferably less than or equal to about 80 wt. %, based on the weight of the adhesive layer.
When the optional second polypropylene which is not amine-functionalized is present, the various polymeric resins in the adhesive layer may be present in any desirable weight ratio, provided that adequate adhesion between the second layer and the substrate layer is obtained. In some embodiments, the optional second polypropylene may be present in a range of between about 5 wt. % and about 80 wt. %; in other embodiments in a range of between about 5 wt. % and about 45 wt. %, in other embodiments in a range of between about 10 wt. % and about 30 wt. %, based on the weight of the adhesive layer.
For use in multilayer articles the adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane may by in the form of a film or sheet. In various embodiments the thickness of the adhesive layer may be in a range of between about 8 microns and about 2500 microns; in other embodiments in a range of between about 25 microns and about 2000 microns; in other embodiments in a range of between about 50 microns and about 1500 microns; in other embodiments in a range of between about 100 microns and about 1300 microns; and in still other embodiments in a range of between about 500 microns and about 1300 microns. In some other embodiments adhesive layer thickness may be in a range of between about 10 microns and about 650 microns; in other embodiments in a range of between about 25 microns and about 400 microns; and in still other embodiments in a range of between about 50 microns and about 260 microns.
In some embodiments of the invention the multilayer article may comprise (i) a first adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane and (ii) optionally at least one second adhesive layer comprising a thermoplastic polyurethane. Said optional second adhesive layer is in contiguous contact with the second layer and said first adhesive layer. The thermoplastic polyurethane of the optional second adhesive layer may be any thermoplastic polyurethane known in the art which provides adhesion to a surface or layer comprising a polymer comprising carbonate structural units. In particular embodiments the thermoplastic polyurethane of the optional second adhesive layer is the same as the thermoplastic polyurethane employed in said first adhesive layer.
In another embodiment the present invention provides methods for making multilayer articles comprising the layer components described herein. In some embodiments the coating layer comprising a block copolyestercarbonate and the second layer comprising a polymer comprising carbonate structural units are formed into a copolyestercarbonate/carbonate-comprising polymer assembly comprising at least two layers. Such an assembly can be made by known methods such as by coextrusion of films or sheets of the two materials. In other embodiments such an assembly can be made by lamination, or solvent or melt coating. In a particular embodiment application of the coating layer to the second layer is performed in a melt process. Suitable methods for application include fabrication of a separate sheet of coating layer followed by application to the second layer, as well as simultaneous production of both layers. Thus, there may be employed such illustrative methods as molding, compression molding, thermoforming, co-injection molding, coextrusion, overmolding, multi-shot injection molding, sheet molding and placement of a film of the coating layer material on the surface of the second layer followed by adhesion of the two layers, typically in an injection molding apparatus; e.g., in-mold decoration. These operations may be conducted under art-recognized conditions.
Assemblies comprising coating layer and second layer may comprise the combined thicknesses of the layers. Such an assembly has a thickness in some embodiments in a range between about 10 microns and about 2500 microns; in other embodiments in a range between about 10 microns and about 1000 microns; in other embodiments in a range between about 10 microns and about 500 microns; and in still other embodiments in a range between about 10 microns and about 250 microns.
The multilayer article may be formed by combining the various layers comprising coating layer, second layer, adhesive layer and substrate by methods known in the art. In one embodiment a copolyestercarbonate/carbonate-comprising polymer assembly and separate adhesive layer may be combined by known methods with substrate layer to form the multilayer article. Known methods include, but are not limited to, lamination and compression molding. Alternatively, the adhesive layer can be formed adjacent to the copolyestercarbonate/carbonate-comprising polymer assembly either after or during a process (such as coextrusion) to make said assembly, and become an integral part of the film assembly which can subsequently be directly formed adjacent to the substrate layer using known processes, for example by use of such methods as heat and pressure. Alternatively, said second layer can be formed adjacent to adhesive layer, for example by directly coextruding said layers together, followed by formation of an assembly with copolyestercarbonate coating layer using known methods which include, but are not limited to, lamination and compression molding. Said assembly can subsequently be directly formed adjacent to the substrate layer using known processes. The copolyestercarbonate/carbonate-comprising polymer assembly can be optionally thermoformed to the approximate shape of the article before molding. In various embodiments any formation step of one layer adjacent to another layer may be performed by known methods which include, but are not limited to, lamination and compression molding.
Application of a structure comprising the coating layer, second layer, and adhesive layer to a substrate layer may also be achieved by charging an injection mold with the structure comprising the coating layer, second layer, and adhesive layer, and injecting the substrate behind it. By this method, in-mold decoration and the like are possible. In one embodiment both sides of the substrate layer may receive the other layers, while in another embodiment they are applied to only one side of the substrate layer.
The multilayer articles comprising the various layer components of this invention are typically characterized by the usual beneficial properties of the substrate layer, in addition to weatherability as may be evidenced by such properties as improved initial gloss, improved initial color, improved resistance to ultraviolet radiation and maintenance of gloss, improved impact strength, and resistance to organic solvents encountered in their final applications. Depending upon such factors as the coating layer/substrate combination, the multilayer articles may possess recycling capability, which makes it possible to employ the regrind material as a substrate for further production of articles of the invention. The multilayer articles often exhibit little or no internal thermal stress which is sometimes induced from CTE mismatch between layers. The multilayer articles may also possess excellent environmental stability, for example thermal and hydrolytic stability. In embodiments of the invention the multilayer article exhibits a ninety-degree peel strength that is greater than that observed in a similar multilayer article made without tielayer or with tielayer consisting of thermoplastic polyurethane alone. In other embodiments the multilayer article exhibits a ninety-degree peel strength of at least 700 Newtons per meter. In still other embodiments the multilayer article exhibits a ninety-degree peel strength of at least 1750 Newtons per meter.
In some specific embodiments the multilayer article may be prepared by a method which is selected from the group consisting of the method (i) comprising the steps of (a) preparing an assembly of coating layer and second layer, and (b) combining said assembly with separate adhesive layer and substrate layer; the method (ii) comprising the steps of (a) preparing an assembly of coating layer and second layer, (b) forming the adhesive layer adjacent to the substrate layer, and (c) combining said assembly with the adhesive layer/substrate layer combination; and the method (iii) comprising the steps of (a) preparing an assembly of coating layer, second layer, and adhesive layer, and (b) forming said assembly adjacent to the substrate layer.
Multilayer articles which can be made which comprise the various layer components of this invention include articles for OVAD applications; exterior and interior components for aircraft, automotive, truck, military vehicle (including automotive, aircraft, and water-borne vehicles), scooter, and motorcycle, including panels, quarter panels, rocker panels, vertical panels, horizontal panels, trim, pillars, center posts, fenders, doors, decklids, trunklids, hoods, bonnets, roofs, bumpers, fascia, grilles, mirror housings, pillar appliques, cladding, body side moldings, wheel covers, hubcaps, door handles, spoilers, window frames, headlamp bezels, headlamps, tail lamps, tail lamp housings, tail lamp bezels, license plate enclosures, roof racks, and running boards; enclosures, housings, panels, and parts for outdoor vehicles and devices; wind turbine blades and housings; enclosures for electrical and telecommunication devices; outdoor furniture; aircraft components; boats and marine equipment, including trim, enclosures, and housings; outboard motor housings; depth finder housings, personal water-craft; jet-skis; pools; spas; hot-tubs; steps; step coverings; building and construction applications such as glazing, roofs, windows, floors, decorative window furnishings or treatments; treated glass covers for pictures, paintings, posters, and like display items; optical lenses; ophthalmic lenses; corrective ophthalmic lenses; implantable ophthalmic lenses; wall panels, and doors; counter tops; protected graphics; outdoor and indoor signs; enclosures, housings, panels, and parts for automatic teller machines (ATM); enclosures, housings, panels, and parts for lawn and garden tractors, lawn mowers, and tools, including lawn and garden tools; window and door trim; sports equipment and toys; enclosures, housings, panels, and parts for snowmobiles; recreational vehicle panels and components; playground equipment; shoe laces; articles made from plastic-wood combinations; golf course markers; utility pit covers; computer housings; desk-top computer housings; portable computer housings; lap-top computer housings; palm-held computer housings; monitor housings; printer housings; keyboards; FAX machine housings; copier housings; telephone housings; phone bezels; mobile phone housings; radio sender housings; radio receiver housings; light fixtures; lighting appliances; reflectors; network interface device housings; transformer housings; air conditioner housings; cladding or seating for public transportation; cladding or seating for trains, subways, or buses; meter housings; antenna housings; cladding for satellite dishes; coated helmets and personal protective equipment; coated synthetic or natural textiles; coated photographic film and photographic prints; coated painted articles; coated dyed articles; coated fluorescent articles; coated foam articles; and like applications. The invention further contemplates additional fabrication operations on said articles, such as, but not limited to, molding, in-mold decoration, baking in a paint oven, lamination, and/or thermoforming.
Without further elaboration, it is believed that one skilled in the art can, using the description herein, utilize the present invention to its fullest extent. The following examples are included to provide additional guidance to those skilled in the art in practicing the claimed invention. The examples provided are merely representative of the work that contributes to the teaching of the present application. Accordingly, these examples are not intended to limit the invention, as defined in the appended claims, in any manner.
Samples were cut into 2.54 centimeter (cm) wide stripes and tested for peel resistance of the tielayer adhesive bond using a 90-degree peel test with a crosshead separation speed of 2.54 cm per minute using an Instron testing device (Model 4505). This adhesion test method is well known to those skilled in the art and is generally described in such references as U.S. Pat. No. 3,965,057. The testing apparatus in this test procedure consisted of a series of movable rollers or supports which allowed the test specimen to be peeled at a constant 90-degree angle along its entire uncut length. The apparatus consisted of a series of five 1.3 cm rollers which were geometrically affixed to two side supports and a base plate. The two lower rollers were adjustable so that the apparatus could accommodate test specimens varying in thickness. A suitable top clamp was used for securing the plastic layer. The test specimen was 15.2 cm in length and 2.54 cm in width. It was insured that a portion of the test specimen remained unbonded. At least 3 specimens were tested for each adhesive sample. In the actual testing procedure, the fixture was affixed to the movable head of the testing machine in a position which would cause the peeled plastic layer to form a 90-degree angle with the test specimen during the test. The test specimen was positioned in the fixture and the free skin clamped securely. The clamp was then pinned to the top head of the testing machine. With no load on the test specimen, the weighing apparatus was then balanced to zero. Provision was made to autograph the peel load versus displacement of the head for a peel distance of at least 10.2 cm. Neglecting the first 2.54 cm of peel, the load required to peel the plastic layer was taken from the autographic curve. The peel strength (P) was then calculated as follows: $P = \frac{peeling load (Newtons)}{width of specimen (meters)} .$
In the following examples the copolyestercarbonate-polycarbonate film assembly comprised a layer of copolyestercarbonate film and a layer of polycarbonate film. The copolyestercarbonate film comprised a copolyestercarbonate with arylate structural units derived from unsubstituted resorcinol, isophthalic acid, and terephthalic acid, and carbonate structural units derived from bisphenol A. The polycarbonate film comprised bisphenol A polycarbonate. The copolyestercarbonate-polycarbonate film assembly was prepared by coextruding a 0.254 mm thick clear copolyestercarbonate film with a 0.5 mm thick pigmented polycarbonate layer. Maleated polypropylene, derived from reaction of polypropylene with maleic anhydride and comprising about 0.55 wt. % anhydride structural units (Fusabond MZ-109D, referred to hereinafter as PP-MA), was obtained from Dupont. A thermoplastic polyurethane (Avalon 70AE; referred to hereinafter as TPU) and polypropylene random copolymer comprising about 90% polypropylene structural units (grade 13M11, referred to hereinafter as PP) were both obtained from Huntsman. Diamines including N-hexylethylenediamine (a primary-secondary diamine) were obtained from Aldrich. A substrate material was ESCORENE PP8224 resin comprising polypropylene structural units and obtained from ExxonMobil.

EXAMPLE 1

A functionalized polypropylene was prepared containing grafted amine groups. A mixture of PP-MA and N-hexylethylenediamine was prepared at 1:1 molar ratio of MA to diamine. The mixture was extruded on a 16 mm co-rotating intermeshing twin-screw extruder with L/D=25 at 180° C. and 40 rpm. The melt was extruded through a 2 mm-diameter circular die, cooled in a room-temperature water bath, and pelletized. A functionalized polypropylene was obtained referred to hereinafter as PP-Fl.

EXAMPLE 2

A compatibilized TPU/PP blend was prepared. A blend of TPU, PP and the functionalized polypropylene of Example 1 (PP-Fl) in a ratio of 70/25/5 by weight was extruded on a twin-screw extruder at 200° C. and 70 rpm. The screw configuration contained two kneading sections. The melt was extruded through a 2-mm-diameter circular die, cooled in a room-temperature water bath, and pelletized. A compatibilized TPU/PP blend was obtained.

EXAMPLE 3

Multilayer articles of (i) copolyestercarbonate-polycarbonate film assembly, (ii) the compatibilized TPU/PP blend of Example 2 and (iii) ESCORENE polypropylene-comprising substrate were prepared by compression molding. A 5 gram (g) sample of the compatibilized TPU/PP blend of Example 2 was pressed into a 0.18 millimeter (mm) thick film and cut into samples 6.4 centimeters (cm)×12.7 cm in dimension. ESCORENE polypropylene-comprising substrate was injection molded into 3.2 mm thick plaques. An ESCORENE plaque substrate was placed in a 3.2 mm thick TEFLON frame (6.4 cm×12.7 cm opening) inside a compression molding press, and the TPU/PP blend film was placed over the substrate, and copolyestercarbonate-polycarbonate film assembly was placed over the TPU/PP blend film with polycarbonate side adjacent to said latter film. The assembly was preheated at 170° C. for 5 minutes between the heated press plates, and then subjected to a pressure of 2.76 megapascals for an additional 3 minutes. The press was then opened and the molded part removed. The adhesion of the copolyestercarbonate-polycarbonate film assembly to the substrate was found to be excellent. The 90-degree peel strength was 3748 Newtons per meter (N/m). The peel failure mode was a combination of interfacial tielayer/copolyestercarbonate-polycarbonate film assembly, interfacial tielayer/substrate, and cohesive substrate failures.

COMPARATIVE EXAMPLE 1

For comparative purposes an uncompatibilized TPU/PP blend in a ratio of 70/30 by weight was prepared by extrusion without functionalized polypropylene under the same processing conditions as Example 2. Multilayer articles of (i) copolyestercarbonate-polycarbonate film assembly, (ii) the uncompatibilized TPU-PP blend and (iii) ESCORENE polypropylene-comprising substrate were prepared by compression molding. A 5 g sample of TPU/PP blend was pressed into a 0.18 mm thick film and cut into samples 6.4 cm×12.7 cm in dimension. Multilayer articles of the layer components were prepared using the same method described in Example 3. The adhesion of the copolyestercarbonate-polycarbonate film assembly to the ESCORENE substrate was found to be very poor. The 90-degree peel strength was found to be less than 525 N/m.

COMPARATIVE EXAMPLE 2

For comparative purposes an uncompatibilized TPU/PP/PP-MA blend in a ratio of 70/25/5 by weight was prepared by extrusion under the same processing conditions as Example 2. Multilayer articles of (i) copolyestercarbonate-polycarbonate film assembly, (ii) TPU/PP/PP-MA blend and (iii) ESCORENE polypropylene-comprising substrate were prepared by compression molding. A 5 g sample of TPU/PP/PP-MA was pressed into a 0.18 mm thick film and cut into a plaque 6.4 cm×12.7 cm in dimensions. Multilayer articles of the layer components were prepared using the same method described in Example 3. The adhesion of the copolyestercarbonate-polycarbonate film assembly to the ESCORENE substrate was found to be very poor. The 90-degree peel strength was found to be less than 525 N/m.

COMPARATIVE EXAMPLE 3

For comparative purposes multilayer articles of (i) copolyestercarbonate-polycarbonate film assembly, (ii) TPU and (iii) ESCORENE polypropylene-comprising substrate were prepared by compression molding. A 5 gram sample of TPU was pressed into a 0.18 mm thick film and cut into a plaque 6.4 cm×12.7 cm in dimensions. Multilayer articles of the layer components were prepared using the same method described in Example 3. It was found that the adhesion between TPU and substrate was very poor. The article delaminated at the interface between TPU and substrate with a 90-degree peel strength of less than 350 N/m.
While the invention has been illustrated and described in typical embodiments, it is not intended to be limited to the details shown, since various modifications and substitutions can be made without departing in any way from the spirit of the present invention. As such, further modifications and equivalents of the invention herein disclosed may occur to persons skilled in the art using no more than routine experimentation, and all such modifications and equivalents are believed to be within the spirit and scope of the invention as defined by the following claims. All Patents, patent applications and published articles cited herein are incorporated herein by reference.

Claims

1. A multilayer article comprising (i) a coating layer comprising a block copolyestercarbonate comprising structural units derived from at least one 1,3-dihydroxybenzene and at least one aromatic dicarboxylic acid, (ii) a second layer comprising a polymer comprising carbonate structural units, (iii) a substrate layer comprising a polypropylene, and (iv) at least one adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane, wherein the coating layer is in contiguous contact with the second layer, and the adhesive layer is in contiguous contact with the second layer and the substrate layer.

2. The article of claim 1 wherein the coating layer comprises at least one 1,3-dihydroxybenzene selected from the group consisting of unsubstituted resorcinol, 2-methyl resorcinol, and mixtures thereof.

3. The article of claim 2 wherein the 1,3-dihydroxybenzene is unsubstituted resorcinol.

4. The article of claim 1 wherein the aromatic dicarboxylic acid is selected from the group consisting of isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, and mixtures thereof.

5. The article of claim 4 wherein the aromatic dicarboxylic acid is a mixture of isophthalic acid and terephthalic acid.

6. The article of claim 5 wherein the ratio of isophthalic-derived structural units to terephthalic-derived structural units is about 0.25-4.0:1.

7. The article of claim 5 wherein the ratio of isophthalic-derived structural units to terephthalic-derived structural units is about 0.40-2.5:1.

8. The article of claim 1 wherein the copolyestercarbonate comprises about 10% to about 99% by weight arylate blocks.

9. The article of claim 1 wherein the copolyestercarbonate comprises about 60% to about 98% by weight arylate blocks.

10. The article of claim 1 wherein the carbonate portion of the copolyestercarbonate comprises structural units derived from bisphenol A.

11. The article of claim 1 wherein the second layer comprises a bisphenol A polycarbonate.

12. The article of claim 1 wherein the second layer further comprises at least one colorant selected from the group consisting of dyes, pigments, metal flakes, and glass flakes.

13. The article of claim 1 wherein the substrate layer comprises at least one homopolypropylene or copolymer comprising structural units derived from propylene, or a blend thereof.

14. The article of claim 13 wherein the substrate layer comprises a copolymer comprising at least about 70 weight percent of structural units derived from propylene.

15. The article of claim 13 wherein the substrate layer comprises a copolymer comprising at least about 90 weight percent of structural units derived from propylene.

16. The article of claim 1 wherein the amine-functionalized polypropylene is derived from reaction of a polypropylene bearing at least one amine-reactive group and an amine compound bearing at least two amine groups.

17. The article of claim 16 wherein the amine-reactive group comprises an anhydride.

18. The article of claim 16 wherein the amine compound bears two amine groups, both of which are primary, or one of which is primary and one of which is secondary.

19. The article of claim 1 wherein the polyurethane is a thermoplastic polyurethane comprising structural units derived from at least one polyol, at least one organic diisocyanate and at least one optional chain extender.

20. The article of claim 19 wherein the polyurethane has a degree of hardness in a range of between about 60° Shore A and about 75° Shore D.

21. The article of claim 19 wherein the polyurethane has a melt flow rate of about 4 to 100 grams per10 minutes as measured by ASTM D-1238.

22. The article of claim 1 wherein the ratio of polyurethane to amine-functionalized polypropylene is in a range of between about 5:95 and about 98:2.

23. The article of claim 1 wherein the adhesive layer further comprises at least one second polypropylene which is not amine-functionalized.

24. The article of claim 23 wherein the second polypropylene is the same as that polypropylene used in the substrate layer.

25. The article of claim 23 wherein the second polypropylene is present in a range of between about 5 wt. % and about 80 wt. %, based on the weight of the adhesive layer.

26. The article of claim 1 wherein the multilayer article exhibits a ninety-degree peel force of at least 700 Newtons per meter.

27. The article of claim 26 wherein the multilayer article exhibits a ninety-degree peel force of at least 1750 Newtons per meter.

28. The article of claim 1 wherein thicknesses of layers are: a coating layer of about 2-2,500 microns; a second layer of about 2-2,500 microns; and an adhesive layer of about 8-2,500 microns.

29. The article of claim 1 which is an OVAD device; exterior or interior component for aircraft, automotive, truck, military vehicle; military automobile, military aircraft, military water-borne vehicle, scooter, motorcycle, including a panel, quarter panel, rocker panel, vertical panel, horizontal panel, trim, pillar, center post, fender, door, decklid, trunklid, hood, bonnet, roof, bumper, fascia, grill, mirror housing, pillar applique, cladding, body side molding, wheel cover, hubcap, door handle, spoiler, window frame, headlamp bezel, headlamp, tail lamp, tail lamp housing, tail lamp bezel, license plate enclosure, roof rack, or running board; an enclosure, housing, panel, or part for outdoor vehicles and devices; a wind turbine blade or housing; an enclosure for an electrical or telecommunication device; outdoor furniture; aircraft component; exterior or interior component for a boat or item of marine equipment, including trim, an enclosure, or housing; an outboard motor housing; depth finder housing, personal water-craft; jet-ski; pool; spa; hot-tub; step; step covering; a building or construction application including glazing, roof, window, floor, decorative window furnishing or treatment; a treated glass cover for a pictures, paintings, poster, or display item; an optical lens; ophthalmic lens; corrective ophthalmic lens; implantable ophthalmic lens; a wall panel or door; a counter top; protected graphic; an outdoor or indoor sign; an enclosure, housing, panel, or part for an automatic teller machine (ATM); an enclosure, housing, panel, or part for a lawn or garden tractor, lawn mower, or tool, including a lawn or garden tool; window or door trim; an item of sports equipment or a toy; an enclosure, housing, panel, or part for a snowmobile; a recreational vehicle panel or component; an item of playground equipment; a shoe lace; an articles made from plastic-wood combinations; a golf course marker; a utility pit cover; a computer housing; a desk-top computer housing; a portable computer housing; a lap-top computer housing; a palm-held computer housings; a monitor housing; a printer housing; a keyboard; a FAX machine housing; a copier housing; a telephone housing; a phone bezel; a mobile phone housing; a radio sender housing; a radio receiver housing; a light fixture; lighting appliance; reflector; network interface device housing; transformer housing; air conditioner housing; cladding or seating for public transportation; cladding or seating for a train, subway, or bus; a meter housing; antenna housing; cladding for satellite dishes; an coated helmet or item of personal protective equipment; a coated synthetic or natural textile; coated photographic film or photographic print; a coated painted article; coated dyed article; coated fluorescent article; or coated foam article.

30. A multilayer article comprising (i) a coating layer comprising a block copolyestercarbonate comprising structural units derived from unsubstituted resorcinol, a mixture of isophthalic acid and terephthalic acid, and bisphenol A; (ii) a second layer comprising a bisphenol A polycarbonate optionally containing at least one colorant; (iii) a substrate layer selected from the group consisting of a homopolypropylene and a copolymer comprising at least about 70 wt. % structural units derived from propylene; and (iv) an adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane;

wherein the coating layer is in contiguous contact with the second layer, and the adhesive layer is in contiguous contact with the second layer and the substrate layer; and wherein the multilayer article exhibits a ninety-degree peel force of at least 700 Newtons per meter.

31. A film assembly comprising (i) a coating layer comprising a block copolyestercarbonate comprising structural units derived from at least one 1,3-dihydroxybenzene and at least one aromatic dicarboxylic acid, (ii) a second layer comprising a polymer comprising carbonate structural units, and (iii) an adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane.

32. The film assembly of claim 31 wherein the coating layer comprises a block copolyestercarbonate comprising structural units derived from unsubstituted resorcinol, a mixture of isophthalic acid and terephthalic acid, and bisphenol A; and the second layer comprises a bisphenol A polycarbonate optionally containing at least one colorant.

33. A method for making a multilayer article comprising (i) a coating layer comprising a block copolyestercarbonate comprising structural units derived from at least one 1,3-dihydroxybenzene and at least one aromatic dicarboxylic acid, (ii) a second layer comprising a polymer comprising carbonate structural units, (iii) a substrate layer comprising a polypropylene, and (iv) at least one adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane, wherein the coating layer is in contiguous contact with the second layer, and the adhesive layer is in contiguous contact with the second layer and the substrate layer,

which method is selected from the group consisting of the method (i) comprising the steps of (a) preparing a pre-assembly of coating layer and second layer, and (b) combining said pre-assembly with separate adhesive layer and substrate layer; the method (ii) comprising the steps of (a) preparing a pre-assembly of coating layer and second layer, (b) forming the adhesive layer adjacent to the substrate layer, and (c) combining said pre-assembly with the adhesive layer/substrate layer combination; and the method (iii) comprising the steps of (a) preparing a pre-assembly of coating layer, second layer, and adhesive layer, and (b) forming said pre-assembly adjacent to the substrate layer.

34. The method of claim 33 wherein the assembly of coating layer and second layer is formed by coextrusion.

35. The method of claim 33 wherein forming said assembly adjacent to the adhesive layer is performed by lamination or compression molding.

36. The method of claim 33 wherein the coating layer comprises at least one 1,3-dihydroxybenzene selected from the group consisting of unsubstituted resorcinol, 2-methyl resorcinol, and mixtures thereof.

37. The method of claim 33 wherein the 1,3-dihydroxybenzene is unsubstituted resorcinol.

38. The method of claim 33 wherein the aromatic dicarboxylic acid is selected from the group consisting of isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, and mixtures thereof.

39. The method of claim 38 wherein the aromatic dicarboxylic acid is a mixture of isophthalic acid and terephthalic acid.

40. The method of claim 39 wherein the ratio of isophthalic-derived structural units to terephthalic-derived structural units is about 0.25-4.0:1.

41. The method of claim 39 wherein the ratio of isophthalic-derived structural units to terephthalic-derived structural units is about 0.40-2.5:1.

42. The method of claim 33 wherein the copolyestercarbonate comprises about 10% to about 99% by weight arylate blocks.

43. The method of claim 33 wherein the copolyestercarbonate comprises about 60% to about 98% by weight arylate blocks.

44. The method of claim 33 wherein the carbonate portion of the copolyestercarbonate comprises structural units derived from bisphenol A.

45. The method of claim 33 wherein the second layer comprises a bisphenol A polycarbonate.

46. The method of claim 33 wherein the second layer further comprises at least one colorant selected from the group consisting of dyes, pigments, metal flakes, and glass flakes.

47. The method of claim 33 wherein the substrate layer comprises at least one homopolypropylene or copolymer comprising structural units derived from propylene, or a blend thereof.

48. The method of claim 47 wherein the substrate layer comprises a copolymer comprising at least about 70 weight percent of structural units derived from propylene.

49. The method of claim 47 wherein the substrate layer comprises a copolymer comprising at least about 90 weight percent of structural units derived from propylene.

50. The method of claim 33 wherein the amine-functionalized polypropylene is derived from reaction of a polypropylene bearing at least one amine-reactive group and an amine compound bearing at least two amine groups.

51. The method of claim 50 wherein the amine-reactive group comprises an anhydride.

52. The method of claim 50 wherein the amine compound bears two amine groups, both of which are primary, or one of which is primary and one of which is secondary.

53. The method of claim 33 wherein the polyurethane is a thermoplastic polyurethane comprising structural units derived from at least one polyol, at least one organic diisocyanate and at least one optional chain extender.

54. The method of claim 53 wherein the polyurethane has a degree of hardness in a range of between about 60° Shore A and about 75° Shore D.

55. The method of claim 53 wherein the polyurethane has a melt flow rate of about 4 to 100 grams per10 minutes as measured by ASTM D-1238.

56. The method of claim 33 wherein the ratio of polyurethane to amine-functionalized polypropylene is in a range of between about 5:95 and about 98:2.

57. The method of claim 33 wherein the adhesive layer further comprises at least one second polypropylene which is not amine-functionalized.

58. The method of claim 57 wherein the second polypropylene is the same as that polypropylene used in the substrate layer.

59. The method of claim 57 wherein the second polypropylene is present in a range of between about 5 wt. % and about 80 wt. %, based on the weight of the adhesive layer.

60. The method of claim 33 wherein the multilayer article exhibits a ninety-degree peel force of at least 700 Newtons per meter.

61. The method of claim 60 wherein the multilayer article exhibits a ninety-degree peel force of at least 1750 Newtons per meter.

62. The method of claim 33 wherein thicknesses of layers are: a coating layer of about 2-2,500 microns; a second layer of about 2-2,500 microns; and an adhesive layer of about 8-2,500 microns.

63. A method for making a multilayer article comprising (i) a coating layer comprising a block copolyestercarbonate comprising structural units derived from unsubstituted resorcinol, a mixture of isophthalic acid and terephthalic acid, and bisphenol A; (ii) a second layer comprising a bisphenol A polycarbonate optionally containing at least one colorant; (iii) a substrate layer selected from the group consisting of a homopolypropylene and a copolymer comprising at least about 70 wt. % structural units derived from propylene; and (iv) an adhesive layer comprising the reaction product of an amine-functionalized polypropylene and a polyurethane,

wherein the coating layer is in contiguous contact with the second layer, and the adhesive layer is in contiguous contact with the second layer and the substrate layer; and wherein the multilayer article exhibits a ninety-degree peel force of at least 700 Newtons per meter;

which method is selected from the group consisting of the method (i) comprising the steps of (a) preparing an assembly of coating layer and second layer, and (b) combining said assembly with separate adhesive layer and substrate layer; the method (ii) comprising the steps of (a) preparing an assembly of coating layer and second layer, (b) forming the adhesive layer adjacent to the substrate layer, and (c) combining said assembly with the adhesive layer/substrate layer combination; and the method (iii) comprising the steps of (a) preparing an assembly of coating layer, second layer, and adhesive layer, and (b) forming said assembly adjacent to the substrate layer.