WO2001012694A1

WO2001012694A1 - Adhesive composition

Info

Publication number: WO2001012694A1
Application number: PCT/US2000/020079
Authority: WO
Inventors: Takahiro Okamatsu
Original assignee: National Starch And Chemical Investment Holding Corporation
Priority date: 1999-08-18
Filing date: 2000-07-21
Publication date: 2001-02-22
Also published as: JP2001055553A; AU6367900A

Abstract

An adhesive composition comprising: (A) 100 parts by weight of a polymer with -Si(R1)(OR2)2 (R?1 and R2¿ are C1-20 hydrocarbon groups which may contain substituents); (B) 1-50 parts by weight of an epoxy resin with -R3-O-(R3: C2-4 alkylene group) per 100 parts by weight (C); (C) 5-200 parts by weight of an epoxy resin other than (B), per 100 parts by weight (A); (D) 0.1-20 parts by weight of a silanol condensation catalyst per 100 parts by weight (A); (E) 0.1-20 parts by weight of an epoxy resin hardener per 100 parts by weight ((B)+(C)); and (F) a silicon compound with a functional group which can react with epoxy resins and -Si(OR4)3(R4: C1-20 hydrocarbon group which may contain substituents), at a weight ratio ((A)+(B)+(C))/(F)=100/0.1-100/20.

Description

ADHESIVE COMPOSITION

Technical Field of Invention

This invention provides a novel adhesive composition with improved adhesion, in particular, it provides an adhesive composition with improved adhesion for use with olefin and acrylic plastics

Vinyl chloride plastics (resins) are inexpensive and have excellent workability and are also flame-retardant Because of these advantages, they have been widely used in various fields However, it has become apparent in recent years that vinyl chloride plastics have problems with respect to the earth's environment, such as producing highly toxic substances such as dioxins when they are burned as a waste treatment and containing plasticizers Therefore, the quantity of vinyl chloride plastics used has fallen and environmental-friendly olefin plastics, which do not produce toxic substances like dioxins when burned, have come to be used instead of them

However, since olefin plastics are non-polar, their surfaces are less paintable than those of polar vinyl chloride plastics Therefore, they are materials which are essentially difficult to adhere by using adhesives Solvent chloroprene adhesives are known to be usable with olefin plastics, but since (organic) solvents are used and chloroprene contains chlorine, their use involves problems related to the earth's environment Moreover, hot melt adhesives are also known which can be used as adhesives for olefin plastics by heating them, but these adhesives have the problem that they cannot be used easily at room temperature

Epoxy adhesives are known as almost universal adhesives, they are typical adhesives for metals and plastics, and they are the first to be tried in adhesion tests of new materials However, epoxy resins have the problem that they are brittle when hardened and have low peeling adhesion There are various reports of adhesives which improve the bπttleness of hardened epoxy resins and increase their peeling adhesion

For example, Japan Patent Kokai No 2-140220 discloses an adhesive composition in which a rubber organic polymer which has cross- linkable methyldimethoxysilyl groups and a polyether in its main chain and a silicon compound which has functional groups which can react with epoxy groups and cross-linkable methyldiethoxysilyl groups are added to an epoxy resin This adhesive certainly shows a good adhesion as an adhesive for meals such as aluminum which have high surface energies This is believed to be because the epoxy resin hardens into a spherical form in the adhesive due to the reaction, and this spherically hardened epoxy resin reinforces the polyether structure of the rubber organic polymer, forming a rubbery hardened state However, when this adhesive is used with low-surface- energy olefin and acrylic plastics, its adhesion is insufficient, according to the inventors' measurements

Problems Which This Invention Seeks to Solve

This invention was made in order to solve these problems Its purpose is to provide a novel adhesive composition with improved adhesion, in particular, an adhesive composition which is ideal for use in adhering olefin and acrylic plastics Means of Solving These Problems

One gist of the present inventions is that it provides a novel adhesive composition which comprises:

(A) a rubber organic polymer with cross-linkable groups shown by the general formula

Si(R¹)(OR²)₂ (I)

(where R¹ and R² are C1 -20 hydrocarbon groups which may contain substituents and may be the same or different from each other): 100 parts by weight;

(B) an epoxy resin which has at least one unit shown by the general formula in its main chain

-R³-0- (II)

(where R³: C2-4 alkylene group): 1-50 parts by weight per 100 parts by weight (C);

(C) an epoxy resin other than the epoxy resin (B): 5-200 parts by weight per 100 parts by weight (A);

(D) a silanol condensation catalyst: 0.1-20 parts by weight per 100 parts by weight (A);

(E) epoxy resin hardener: 0.1 -20 parts by weight per 100 parts by weight ((B)+(C)); and

(F) a silicon compound having functional groups which can react with epoxy groups, and cross-linkable groups shown by the general formula

-Si(OR⁴)₃ (III) (where R⁴ C1 -20 hydrocarbon group which may contain substituents), at a weight ratio ((A)+(B +(C))/(F)=100/0 1-100/20 In particular, said adhesive composition is suitable for use with olefin and acrylic plastics

In this invention, the "rubber organic polymer (A)" refers to a polymer which has cross-linkable silyl groups shown by formula (I) and a polymer which forms its backbone

The polymer which forms the backbone of (A) is not particularly limited as long as it has a structure which can impart rubber elasticity to (A)

Examples of polymers which can serve as the backbone of (A) include

(A1 ) polyethers, such as polyethylene oxide, polypropylene oxide, polybutylene oxide, etc ,

(A2) polyesters obtained by condensation polymerization of dicarboxyhc acids (such as terephthalic acid, isophthalic acid, adipic acid, etc ) and glycols (such as ethylene glycol, propylene glycol, etc ) or polyesters obtained by ring-opening polymerization of lactones,

(A3) polyolefins such as ethylene-propylene copolymers, polysiobutylene, etc ,

(A4) polymers or copolymers of dienes, such as polybutadiene, polyisoprene, isoprene/butadiene copolymers, etc ,

(A5) copolymers of dienes, such as copolymers of butadiene or isoprene and styrene or acrylonitπle, etc ,

(A6) hydrogenated dienes, such as hydrogenated polyisoprene, polybutadiene, or isoprene/butadiene copolymers,

(A7) poly(meth)acrylιc acid esters obtained by polymerizing (meth)acrylιc acid esters, such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, etc ,

(A8) copolymers of the (meth)acrylιc acid esters mentioned in (A7) and vinyl acetate, acrylonitπle, styrene, ethylene, etc ,

(A9) polymers obtained by graft-polymerizing vinyl monomers onto any of the polymers mentioned in (A1 )-(A8)

(A10) polysulfide polymers

(In these specifications, acrylic acid and methacrylic acid are referred to together as "(meth)acrylιc acids ") These polymers can be used individually or in combinations, they can also be used as random or block copolymers Furthermore, liquid polymers are preferable, since they are easier to handle

The polyethers (A1 ) mentioned above are particularly preferable as the polymers forming the backbone of (A) For example, polyethers with at least one unit shown by the general formula

-R⁵-0- (IV)

(where R⁵ is a C2-4 bivalent alkylene group), such as polyethylene oxide, polypropylene oxide, etc , are desirable

Furthermore, the cross-linkable silyl groups of (A) are cross-linkable groups shown by the general formula

- Sι(R¹)(OR²)₂ (I)

(where R¹ and R² are C1-20 hydrocarbon groups which may contain substituents and may be the same or different from each other), and are reactive bivalent silyl groups Specific examples of the R¹ groups are hydrocarbon groups, such as methyl, ethyl, propyl, isopropyl, butyl, etc , methyl and ethyl groups are especially desirable

Specific examples of the R² groups are alkyl groups, such as methyl, ethyl, propyl, etc., aryl groups, such as phenyl, and alkyl groups with ether bonds, such as methoxyethyl, ethoxyethyl, etc , groups, alkyl groups are especially desirable

It is desirable to have 1-20, preferably 1-10, and especially preferably 2-6 of these bivalent reactive silyl groups per molecule, on average, in the rubber organic polymer (A)

Moreover, since the bivalent reactive silyl groups have excellent reactivities, it is preferable for them to be on the ends of the molecule (A)

The number average molecular weight of the rubber organic polymer (A) used in this invention should be 2000-20000, preferably 2000- 15000, and especially preferably 5000-12000

Furthermore, it is desirable for (A) to be a liquid, with a viscosity of 500-25000 cps, preferably 1000-20000 cps, and especially preferably 3000- 20000 cps at 23°C

The rubber organic polymer (A) can be manufactured by known methods (see Japan Patent Kokai No 61-268720), but commercial ones can also be used

Specifically, one can use Silyl SAT 200, Silyl SAT 030, Silyl SAT 010, and Silyl SAX 350 (trade names), made by Kaneka Corporation

In this invention, the "epoxy resin (B)" refers to an epoxy resin which has at least one unit shown by the general formula -R³-0- (II)

(where R³ C2-4 alkylene group) in its main chain

A characteristic of the adhesive composition of this invention is that it contains both this epoxy resin (B) with an alkyleneoxy unit in its main chain and the general epoxy resin (C) mentioned below

Examples of these epoxy resins (B) are

(B1 ) glycidyl ether epoxy resins, such as bisphenol A propylene oxide adducts,

(B2) glycidyl ether epoxy resins, such as bisphenol A ethylene oxide adducts,

(B3) propylene oxide glycidyl ether epoxy resins,

(B4) tetramethylene oxide glycidyl ether epoxy resins,

(B5) hexamethylene diglycidyl ether epoxy resins, and

(B6) neopentyl glycol diglycidyl ether epoxy resins

These epoxy resins (B) can be used individually or in combinations

Among these epoxy resins (B), ones which have at least 2 epoxy groups per molecule at the ends of the epoxy resin are desirable, since they have high cross-linking reactivities and good miscibilities after the reaction with the epoxy resins (C) which is mentioned below

Furthermore, epoxy resins (B) which are liquid at room temperature are preferable, since they are easier to handle Also, epoxy resins (B) which are solid at ordinary temperatures may be used by dissolving them in liquid epoxy resins (B)

The epoxy resins (B) can be manufactured by publicly known methods, but one can also use commercial ones For example, BEO-60E (trade name, New Japan Chemical Co , Ltd ), PPDGE (trade name, BTR Japan Ltd ), and ED-503, ED-506, and ED-532 (trade names, Asahi Denka Kogyo K K ) are ideal for this use

It is preferable to use 1-50 parts by weight, and especially preferably 3-10 parts by weight, epoxy resin (B) per 100 parts by weight epoxy resin (C), mentioned below

In this invention, the "epoxy resin (C)" is not particularly limited, one can use any epoxy resin which is generally used, except the epoxy resins (B) mentioned above

Examples of these epoxy resins (C) include

(C1 ) flame-retardant epoxy resins, such as epichlorohydπn- bisphenol A epoxy resin, epichlorohydπn-bisphenol AD epoxy resin, epichlorohydπn-biphenyl epoxy resin, epichlorohydπn-bisphenol F epoxy resin, glycidyl ether of tt rabromobisphenol A, phosphoric acid phenyl glycidyl ether, etc ,

(C2) epoxy resins obtained by hydrogenating the aromatic rings of the epoxy resins in (C1 ),

(C3) novolak-type epoxy resins,

(C4) p-oxybenzoic acid glycidyl ether ester epoxy resins,

(C5) aminophenyl epoxy resins,

(C6) diaminodiphenylmethane epoxy resins,

(C7) urethane-modified epoxy resins with urethane bonds,

(C8) alicyclic epoxy resins, (C9) epoxy compounds, such as N,N-dιglycιdylanιlιne, N,N- dιglycιdyl-o-toluιdιne, tπglycidyl isocyanurate, etc ,

(C10) glycidyl ethers of glycol, such as polyalkylene glycol diglycidyl ether,

(C11 ) glycidyl ethers of polyhydric alcohols, such as glycerol,

(C12) hydantoin-type epoxy resins, and

(C13) epoxy compounds of unsaturated polymers, such as petrochemical resins

Among these epoxy resins (C), ones which have at least 2 epoxy groups per molecule at the ends of the epoxy resin are desirable, since they have excellent characteristics with respect to the environment, such as heat resistance and durability of the cured products, and also have good adhesion

In particular, bisphenol A-type epoxy resins are especially desirable

These epoxy resins (C) can be used individually or in combinations

Furthermore, epoxy resins (C) which are liquid at room temperature are preferable, since they are easier to handle Also, epoxy resins (C) which are solid at ordinary tempe^ratures may be used by dissolving them in liquid epoxy resins (C)

The epoxy resins (C) can be manufactured by publicly known methods, but one can also use commercial ones For example, Epikote 828 (trade name, Yuka Shell Epoxy Co Ltd ) and Epomik R-140 (trade name, Mitsui Chemical Co Ltd ) are ideal for this use It is preferable to use 5-200 parts by weight, and especially preferably 10-150 parts by weight, epoxy resin (C) per 100 parts by weight rubber organic polymer (A)

In this invention, the "silanol condensation catalyst (D)" refers to a catalyst which accelerates the condensation reaction of the silanol groups which are produced by hydrogenating the cross-linkable silyl groups in formulas (I), (III), and (V) (mentioned below) They are not particularly limited, one can use presently known acidic or basic catalysts

Examples of the silanol condensation catalysts (D) are

(D1 ) titanic acid esters, such as tetrabutyl titanate, tetrapropyl titanate, etc ,

(D2) tin carboxylic acid salts, such as dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, dibutyltin diphthalate, tin octylate, tin stearate, tin naphthenate, etc ,

(D3) tin compounds, such as reaction products of dibutyltin oxide and phthalic acid esters, dibutyltin acetylacetonate, etc ,

(D4) organoaluminum compounds, such as aluminum tπsacetylacetonate, aluminum tπsethylacetoacetate, diisopropoxyaluminum ethyl acetoacetate, etc ,

(D5) chelate compounds, such as zirconium tetraacetylacetonate, titanium tetraacetylacetonate, etc ,

(D6) lead compounds, such as lead octylate,

(D7) amines, such as butylamine, monoethanolamine, monoethanolamine, tπethylenetetramine, guanidine, 2-ethyl-4- methylimidazole, 1 ,8-dιazabιcyclo(5,4,0)undecene-y (DBU), etc , and (D8) carboxylic acid, etc , salts of the amines (D7) mentioned above

Especially desirable as silanol condensation catalysts (D) are dibutyltin dilaurate, dibutyltin diacetate, and dibutyltin acetylacetonate

These silanol condensation catalysts (D) can be used individually or in combinations

It is desirable to use 0 1-20 parts by weight, preferably 0 5-10 parts by weight, and especially preferably 0 8-2 0 parts by weight, silanol condensation catalysts (D) per 100 parts rubber organic polymer (A)

In this invention, the "epoxy resin hardener (E)" is not particularly limited, one can use any generally used epoxy resin hardeners For example

(E1 ) amines, such as tπethylenetetramine, tetraethylenepentamine, diethylaminopropylamine, N-aminoethylpipeπdine, xylylenediamine, phenylenediamine, diaminophenylmethane, diaminodiphenylsulfone, isophoronediamine, 2,4,6- tπs(dιmethylamιnomethyl)phenol, etc ,

(E2) tertiary amines,

(E3) polyamide resins,

(E4) imidazoles,

(E5) dicyandiamides,

(E6) boron tπfluoπde compounds,

(E7) carboxylic anhydrides, such as phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, endomethyiene tetrahydrophthalic anhydride, dodecinylsuccinic anhydride, pyromellitic anhydride, chlorendic anhydride, etc ,

(E8) alcohols,

(E9) phenols, and

(E10) carboxylic acids

2,4,6-Tπs(dιmethylamιnomethyl)phenol is especially desirable

These epoxy resin hardeners (E) can be used individually or in combination

It is desirable to use 0 1 -20 parts by weight, preferably 1-15 parts by weight, and especially preferably 5-10 parts by weight, epoxy resin hardeners (E) per 100 parts (epoxy resin (B) + epoxy resin (C))

In this invention, the "silicon compound (F)" refers to silicon compounds which have functional groups which can react with the epoxy groups of the epoxy resins (B) and (C) and cross-linkable silyl groups shown by the general formula

-Sι(OR⁴)₃ (lll)

(where R⁴ is a C1-20 hydrocarbon group which may contain substituents) A characteristic of this invention is that the cross-linkable groups shown by formula (III) are reactive tnvalent silyl groups

Examples of the functional groups of the silicon compounds (F) which can react with epoxy groups are primary, secondary, and tertiary ammo groups, mercapto groups, epoxy groups, carboxyl groups, etc Moreover, n formula (III), specific examples of the groups R⁴ are hydrocarbon groups such as methyl, chloromethyl, fluoromethyl, ethyl, phenyl, vinyl, etc , groups However, the methyl group is especially desirable

Examples of such silicon compounds (F) are

(F1 ) silicon compounds containing ammo groups, such as - aminopropyltπmethoxysilane, -a m inopropyltπethoxysilane, aminoethyltπethoxysilane, -a m ιnopropyltrι(2-methoxyethoxy)sιlane, N- - (aminoethyl)- -aminopropyltπmethoxysilane, N- - (aminoethyl)- - aminopropyltπethoxysilane, N- - (N-vιnylbenzylamιnoethyl)- - aminopropyltnmethoxysilane, -a n ilinopropyltπmethoxysilane, etc ,

(F2) silicon compounds containing mercapto groups, such as

- mercaptopropyltπmethoxysilane, -m e rcaptopropyltπethoxysilane, etc ,

(F3) silicon compounds containing epoxy bonds, such as - glycidoxypropyltπmethoxysilane, -g l ycidoxypropyltπethoxysilane, - (3 , 4- epoxycyclohexyl)ethyltπmethoxysιlane, etc , and

(F4) carboxysilane compounds, such as carboxyethyltπmethoxysilane, -c a rboxyethyltrι(2-methoxyethoxy)sιlane, N- - (N-carboxymethylaminoethyl)- - amιnopropyl(trιmethoxy)sιlane, etc

Among these silicon compounds (F), ones shown by the general formula

R⁶-R⁷-Sι(OR⁴)₃ (V)

(where R⁶ is an ammo group (which may be replaced with a C1-4 alkyl group containing an ammo group), R⁷ is a C1-4 bivalent alkylene group, and R⁴ is a C1-20 hydrocarbon group which may also have substituents) are preferable In particular, N- - (aminoethyl)- - aminopropyltπmethoxy-silane and N- - (aminoethyl)- -aminopropyltπethoxysilane are especially desirable

These compounds may be used individually or in combination They can be manufactured by publicly known methods, or one can use commercially available ones

In this invention, the silicone compounds (F) should be used in weight ratios ((A)+(B)+(C))/(F), with respect to the rubber organic polymers (A), epoxy resins (B), and epoxy resins (C), in the range of 100/0 1 -100/20, preferably 100/0 5-100/10, and especially preferably 100/1-100/5

Furthermore, it is desirable to add moisture to the adhesive compositions of this invention

The adhesive compositions formed from the ingredients (A)-(F) mentioned above require moisture for hardening This moisture is ordinarily supplied from the air surrounding the adhesive compositions Therefore, if the supply of moisture to the adhesive composition is insufficient, problems may be caused in the development of the desired adhesion Examples of such cases are ones in which the adhesive layer is thick, ones in which the objects being adhered are not very permeable to moisture, such as plastics and metals, and cases in which long periods are needed to harden the adhesive all the way into the adhesive layer

Therefore, it is desirable to add moisture to the adhesive composition in order to control the adhesion in a suitable manner

The various ingredients (A)-(F) of the adhesive composition of this invention originally contain moisture That is, the ingredients (A)-(F) may pick up moisture in their manufacturing, transportation, and storage processes This moisture also contributes to the hardening of the adhesive composition of this invention Therefore, it is preferable to add moisture after the quantity of moisture contained in each ingredient (A)-(F) is measured, e g , by using the Karl Fischer method, and controlled to the desired value by heating each ingredient while reducing pressure In this invention, the ingredients (A)-(F) have gone through ordinary manufacturing, transportation, and storage processes, and ingredients which have moisture contents which satisfy the standards of the respective ingredients are used If necessary, it is preferable to measure the quantity of the moisture contained in each ingredient (A)-(F) and control it to the desired value before using it

The quantity of moisture added is ordinarily 0 05-1 0 part by weight, preferably 0 05-0 8 part by weight, and especially preferably 0 2-0 5 part by weight, per 100 parts by weight of the rubber organic polymer (A) If the quantity of moisture added is less than 0 02 part by weight per 100 parts by weight of the rubber organic polymer (A), the curing ability of the adhesive composition is reduced, which is not desirable On the other hand, if it exceeds 0 8 part by weight, the storage stability of the adhesive composition is reduced, which is not desirable either

It is desirable for the quantity of moisture (the quantities of moisture originally contained in the ingredients (A)-(F) + the quantity of added moisture mentioned above) to be 500-10000 ppm, preferably 1500-6000 ppm, and especially preferably 3000-6000 ppm, in the state before the adhesive composition is cured, assuming that all of the ingredients (A)-(F) are mixed to form one mixture If this quantity is less than 500 ppm, the curing ability of the adhesive composition is reduced, which is not desirable On the other hand, if it exceeds 10000 ppm, the storage stability of the adhesive composition is reduced, which is not desirable either In addition to the rubber organic polymer (A), the epoxy resin (B), the epoxy resin (C), the silanol condensation catalyst (D), the epoxy resin hardener (E), and the silicon compound (F), additives which are usually added to adhesive compositions may also be added, e g , fillers, plasticizers, anti-aging agents, ultraviolet absorbents, lubricants, pigments, blowing agents, viscosity regulators, etc These additives can be used individually or in combination, and can be selected according to the properties that are needed

The adhesive composition of this invention can be used in various forms

For example, all of the ingredients (A)-(F) of the adhesive composition of this invention can be prepared before it is used and, immediately before use, all of the ingredients may be weighed and all of the weighed ingredients (A)-(F) can be mixed together and used

Therefore, the adhesive composition of this invention can be used as a one-liqu id-type adhesive composition

Furthermore, the adhesive composition of this invention can be used by weighing all of the ingredients (A)-(F) beforehand and making a 2- liquid or 3-lιquιd adhesive composition These 2 or 3 liquids are then mixed in specific proportions immediately before use

Therefore, the adhesive composition of this invention can also be provided as a 2-lιquιd or 3-lιquιd adhesive composition In this case, a 2-lιquιd adhesive composition is preferable In particular, a 2-iιquιd adhesive composition composed of a composition comprising the rubber organic polymer (A), the epoxy resin hardener (E), and the silicon compound (F) and another composition comprising the epoxy resin (B), the epoxy resin (C), and the silanol condensation catalyst (D)

Furthermore, the adhesive composition of this invention can be used by weighing all of the ingredients (A)-(F) beforehand and forming one combination of them, and then mixing all of these weighed ingredients together immediately before use

Therefore, a combination of the rubber organic polymer (A), the epoxy resin (B), the epoxy resin (C), the silanol condensation catalyst (D), the epoxy resin hardener (E), and the silicon compound (F) ingredients for constituting the adhesive composition of this invention is provided

The adhesive composition of this invention can be manufactured by using methods which are ordinarily used in manufacturing adhesive compositions For example, the adhesive composition of this invention can be manufactured by using a compounding vessel in which the ingredients can be stirred and heated if necessary to regulate the temperature It is desirable to heat the ingredients (A)-(F) as needed while they are being stirred and mixed When 2- or 3-lιquιd adhesive compositions are made, it is desirable to mix the ingredients (A)-(F) which correspond to the 2- or 3-lιquιd compositions, performing the same kinds of operations as those described above

Furthermore, when one is manufacturing an adhesive composition of this invention with moisture added, it is desirable to add the moisture while the quantity of moisture is being controlled during the manufacturing of the adhesive composition For this manufacture, it is desirable to use, for example, a compounding vessel the temperature of which can be regulated by heating it to a temperature of 80°C or higher, preferably 100°C or higher, and in which stirring can be performed under a vacuum After the ingredients (A)-(F) are stirred and mixed and the mixture is heated under a vacuum to dehydrate the moisture in it to below a specific value, it is desirable to add a specific quantity of moisture When a 2- or 3-lιquιd adhesive composition is being made, it is desirable to mix the ingredients (A)-(F) which correspond to the 2- or 3-lιquιd composition, performing the same kinds of operations as those described above Furthermore, low-molecular-weight silane compounds, e g , methyl tπmethoxysilane, can be added as dehydrating agents

In addition, when the adhesive composition of this invention is made into a 2- or 3-lιquιd adhesive composition, the total quantity of the specified moisture may be added to any one of the compositions which constitute the 2- or 3-lιquιd adhesive composition, or the specified quantity of moisture may be suitably divided and added to 2 or more of the compositions which constitute the 2- or 3-lιquιd adhesive composition However, the moisture content percentage and the storage stabilities of the ingredients constituting the composition should be taken into consideration In particular, since the silanol condensation catalyst (D) is ordinarily constituted by organic metal compounds, and the organic metal compounds readily decompose when their moisture contents are high, it is desirable to add the moisture in such a way that the composition or compositions which do not contain the silanol condensation catalyst (D) have higher moisture contents

The adhesive composition of this invention is especially good for use with plastics with small surface energies, such as olefin or acrylic plastics, but it can also be used with metals such as iron, copper, aluminum, etc , plastics such as polyvinyl chloride, ABS resins, fluorine resins, silicone resins, Bakehte, polystyrene, polycarbonate, polyacetal, 6-nylon, polyether ether ketone, polyether sulfone, polysulfone, polyamideimide, polyimide, polyethylene tetraphthalate, polybutylene terephthalate, polyphenylene sulfide, modified polyphenylene oxide, etc , rubbers such as natural rubber, butadiene rubber, styrene-butadiene rubber, butyl rubber, NBR, silicon

rubber, EPDM, acrylic rubber, fluorine rubber, etc , wood or hard boards, and natural or artificial stone, such as slate, calcium silicate slabs, mortar, concrete, marble, granite, etc

The adhesive composition of this invention exhibits excellent adhesion when it is used with olefin and acrylic plastics, which have small surface polarities The reasons for this are believed to be as follows

18/31

The adhesive composition of this invention is believed to form a polymer alloy the mam ingredients of which are the rubber organic polymer

(A), the epoxy resin (B), and the epoxy resin (C) The silicon compound (F) is believed to increase the strength of this polymer alloy be contributing to the miscibility of the ingredients (A), (B), and (C)

When the adhesive composition of this invention is applied to the objects being adhered, it is believed that it is primarily the epoxy resin (C) which coordinates with the polar groups on the surfaces of these objects, and it is primarily the rubber organic polymer (A) with cross-linkable groups and the epoxy resin (B) which coordinate with low-polarity olefin plastics, etc If (B) were not present, only (A) would coordinate with low-polarity olefin plastics, etc With (A) only, the coordinating force would be insufficient, and the adhesion force would therefore be insufficient Since (B) has the property of coordinating with low-polarity olefin plastics, etc , and increasing the wettability of their surfaces, the presence of (B) is believed to increase the adhesion to low-polarity olefin plastics, etc

Furthermore, the adhesive composition of this invention is believed to show excellent adhesion to olefin and acrylic plastics which have surfaces with small polarities for the reasons mentioned above, but the adhesive composition of this invention is not limited in any way by these reasons

Working Examples

This invention will be explained in detail below by working and comparison examples, but these examples are only embodiments of this invention, and do not limit it in any way

The ingredients (A)-(F) used to prepare the adhesive compositions of the working and comparison examples are shown below

(a1 ) and (a2) are rubber organic polymers (A)

(a1 ) is a polypropylene oxide with a molecular weight of 5000-6000 and with dimethoxysilyl groups on its ends (Kaneka Corporation, trade name "Kaneka Silyl SAT 30")

(a2) is a polypropylene oxide with a molecular weight of 9000- 10000 and with dimethoxysilyl groups on its ends (Kaneka Corporation , trade name "Kaneka Silyl SAT 200")

(b1 ) and (b2) are epoxy resins (B)

(b1 ) is a bisphenol A epoxy resin with a hexaethylene oxide mam chain (New Japan Chemical Co Ltd , trade name "BEO-60E") (b2) is an epoxy resin with a polypropylene oxide main chain (BTR Japan Ltd , trade name "PPDGE")

(d ) is a bisphenol A epoxy resin of the epoxy resin ingredient (C) (Yuka-Shell Epoxy Co Ltd , trade name "Epikote 828")

(d1 ) is a 3,4,6-tπsdιamιnomethyl phenol (also known as "DMP 30") of the silanol condensation catalyst ingredient (D) (BTR Japan Ltd , "Anchormine K54")

(e1 ) is a tin compound of the epoxy resin hardener ingredient (E) (Sankyo Yuki Gosei Co Ltd , trade name "SCAT1 ")

(f1 ) is N- - (aminoethyl)- - aminopropyltπmethoxysilane

[NH₂C₂H₄NHC₃H₆Sι(OCH₃)₃] of the silicon compound ingredient (F) (Nippon Unicar Co Ltd , trade name "A1120")

Working Example 1

While stirring 100 g polypropylene oxide with a molecular weight of

5000-6000 and with dimethoxysilyl groups on its ends (Kanegafuchi Chemical Industry Co , trade name "Kanekasaiπru SAT 30") (a1 ), 50 g bisphenol A epoxy resin (Yuka Shell Epoxy Co , trade name "Epicoat 828") (d ) were added at room temperature Next, 5 g bisphenol A epoxy resin with a hexaethylene oxide mam chain (New Japan Chemical Co , trade name

"BEO-60E") were added, after which 5 g 3,4,6-trιsdιamιnomethyl phenol (also known as "DMP 30") (BTR Co , "Ankamm K54") (d1 ), 1 5 g tin compound

(Sankyo Yuki Gosei Co, trade name "SCAT1 ") (e1 ), 3 g N- -(am i n oethyl)-

- aminopropyltπmethoxysilane [NH2C2H4NHC3H6Sι(OCH3)3] (Nippon Unicar Co , trade name "A1120") (f1 ), and 0 5 g distilled water were added, and the mixture was thoroughly stirred to obtain the target adhesive composition

Evaluation of adhesive composition

The adhesive composition of Working Example 1 was applied to a constant thickness of 0 2 mm on 2 polyethylene substrates (300 mm x 300 mm x 0 2 mm) using a bar coater and the two substrates were compressed together by hand After these polyethylene films were sandwiched between plates with flat surfaces, a load of 0 2 kg/cm2 was applied for 3 days at 20°C The sample obtained after 3 days was cut to a width of 25 mm and this was used as the evaluation sample

Using the same method as that of JIS K6854, the aforementioned

25 mm wide evaluation sample was tested at 23°C in a T peeling test at a cross-head speed of 50 mm/mm The force used at this time was measured and taken as the adhesion of the adhesive of Working Example 1 The results are shown as the PE adhesion in Table 1

Furthermore, another evaluation sample was made in the same manner from polypropylene application substrates and the same T peeling test was performed to measure the adhesion of the adhesive of Working Example 1 The results are shown as the PP adhesion in Table 1

Working Example 2

The adhesive composition of Working Example 2 was obtained by the same method as that described in Working Example 1 , except that 10 g (b1 ) were used instead of the 5 g (b1 ) The adhesive composition of Working Example 2 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 1

Working Example 3

The adhesive composition of Working Example 3 was obtained by the same method as that described in Working Example 1 , except that 100 g (d ) were used instead of the 50 g (d ) and 8g (d1 ) were used instead of the 5g (d1 )

The adhesive composition of Working Example 3 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 1

Working Example 4

The adhesive composition of Working Example 4 was obtained by the same method as that described in Working Example 1 , except that 100 g (d ) were used instead of the 50 g (d ), 10 g (b1 ) were used instead of the 5 g (b1 ), and 8 g (d1 ) were used instead of the 5 g (d1 )

The adhesive composition of Working Example 4 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 1 Working Example 5

The adhesive composition of Working Example 5 was obtained by the same method as that described in Working Example 1 , except that 5 g epoxy resin with a polypropylene oxide mam chain (BTR Co , trade name "PPDGE") (b2) were used instead of the 5 g (b1 )

The adhesive composition of Working Example 5 was evaluated by the same method as that descπbed in Working Example 1 and the results are shown in Table 1

Working Example 6

The adhesive composition of Working Example 6 was obtained by the same method as that described in Working Example 1 , except that 10 g (b2) were used instead of the 5 g (b1 )

The adhesive composition of Working Example 6 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 1

Working Example 7

The adhesive composition of Working Example 7 was obtained by the same method as that described in Working Example 1 , except that 100 g (d ) were used instead of the 50 g (d ), 5 g (b2) were used instead of the 5 g (b1 ), and 8 g (d1 ) were used instead of the 5 g (d1 )

The adhesive composition of Working Example 7 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 1 Working Example 8

The adhesive composition of Working Example 8 was obtained by the same method as that described in Working Example 1 , except that 100 g (d ) were used instead of the 50 g (d ), 10 g (b2) were used instead of the 5 g (b1 ), and 8 g (d1 ) were used instead of the 5 g (d1 )

The adhesive composition of Working Example 8 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 1

Working Example 9

The adhesive composition of Working Example 9 was obtained by the same method as that described in Working Example 1 , except that 5 g (b1 ) and 5 g (b2) were used instead of the 5 g (b1 ).

The adhesive composition of Working Example 9 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 1

Working Example 10

The adhesive composition of Working Example 10 was obtained by the same method as that described in Working Example 1 , except that 100 g (d ) were used instead of the 50 g (d ), 10 g (b1 ) and 10 g (b2) were used instead of the 5 g (b1 ), and 8 g (d1 ) were used instead of the 5 g (d1 )

The adhesive composition of Working Example 10 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 1

Table 1

a) Unit: g b) Adhesion with respect to polyethylene; unit: kgf/25 mm c) Adhesion with respect to polypropylene; unit' kgf/25 mm

Comparison Example 1

The adhesive composition of Comparison Example 1 was made by the same method as in Working Example 1 , except that the 5 g (b1 ) were not used.

The adhesive composition of Comparison Example 1 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 2 Comparison Example 2

The adhesive composition of Comparison Example 2 was made by the same method as in Working Example 1 , except that 100 g (d ) were used instead of the 50 g (d ) and the 5 g (b1 ) were not used

The adhesive composition of Comparison Example 2 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 2

Comparison Example 3

The adhesive composition of Comparison Example 3 was made by the same method as in Working Example 1 , except that (b1 ), (d ), and (d1 ) were not used at all

The adhesive composition of Comparison Example 3 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 2

Comparison Example 4

The adhesive composition of Comparison Example 4 was made by the same method as in Working Example 1 , except that (d ) was not used at all and 0 5 g (d1 ) was used instead of the 5 g (d1 )

The adhesive composition of Comparison Example 4 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 2 Comparison Example 5

The adhesive composition of Comparison Example 5 was made by the same method as in Working Example 1 , except that (d ) was not used at all, 10 g (b1 ) were used instead of the 5 g (b1 ), and 1 g (d1 ) was used instead of the 5 g (d1 ).

The adhesive composition of Comparison Example 5 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 2.

Comparison Example 6

The adhesive composition of Comparison Example 6 was made by the same method as in Working Example 1 , except that (d ) was not used at all, 5 g (b2) were used instead of the 5 g (b1 ), and 0.5 g (d1 ) was used instead of the 5 g (d1 ).

The adhesive composition of Comparison Example 6 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 2.

Comparison Example 7

The adhesive composition of Comparison Example 7 was made by the same method as in Working Example 1 , except that (d ) was not used at all, 10 g (b2) were used instead of the 5 g (b1 ), and 1 g (d1 ) was used instead of the 5 g (dl ). The adhesive composition of Comparison Example 7 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 2

Table 2

b) Adhesion with inspect to polyethylene, unit kgf/25 mm c) Adhesion with respect to polypropylene, unit kgf/25 mm

Working Example 11

The adhesive composition of Working Example 11 was obtained by the same method as that described in Working Example 1 , except that a polypropylene oxide with a molecular weight of 9000-10000 and with dimethoxysilyl groups on its ends (Kaneka Corporation, trade name "Kaneka Silyl SAT 200") (a2) was used instead of (a1 ) The adhesive composition of Working Example 11 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Working Example 12

The adhesive composition of Working Example 12 was obtained by the same method as that described in Working Example 1 , except that (a2) was used instead of (a1 ) and 10 g (b1 ) were used instead of the 5 g (b1 )

The adhesive composition of Working Example 12 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Working Example 13

The adhesive composition of Working Example 13 was obtained by the same method as that descπbed in Working Example 1 , except that (a2) was used instead of (a1 ), 100 g (d ) were used instead of the 50 g (d ), and 8 g (d1 ) were used instead of the 5 g (d1 )

The adhesive composition of Working Example 13 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Working Example 14

The adhesive composition of Working Example 14 was obtained by the same method as that described in Working Example 1 , except that (a2) was used instead of (a1 ), 100 g (d ) were used instead of the 50 g (d ), 10 g (b1 ) were used instead of the 5 g (b1 ), and 8 g (d1 ) were used instead of the 5 g (d1 )

The adhesive composition of Working Example 14 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Working Example 15

The adhesive composition of Working Example 15 was obtained by the same method as that described in Working Example 1 , except that (a2) was used instead of (a1 ), 5 g (b2) were used instead of the 5 g (b1 )

The adhesive composition of Working Example 15 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Working Example 16

The adhesive composition of Working Example 16 was obtained by the same method as that described in Working Example 1 , except that (a2) was used instead of (a1 ) and 10 g (b2) were used instead of the 5 g (b1 )

The adhesive composition of Working Example 16 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Working Example 17 The adhesive composition of Working Example 17 was obtained by the same method as that described in Working Example 1 , except that (a2) was used instead of (a1 ), 100 g (d ) were used instead of the 50 g (d ), 5 g

(b2) were used instead of the 5 g (b1 ), and 8 g (d1 ) were used instead of the 5 g (d1 )

The adhesive composition of Working Example 17 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Working Example 18

The adhesive composition of Working Example 18 was obtained by the same method as that described in Working Example 1 , except that (a2) was used instead of (a1 ), 100 g (d ) were used instead of the 50 g (d ), 10 g

The adhesive composition of Working Example 18 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Working Example 19

The adhesive composition of Working Example 19 was obtained by the same method as that described in Working Example 1 , except that (a2) was used instead of (a1 ) and 5 g (b1 ) and 5 g (b2) were used instead of the 5 9 (b1 ) The adhesive composition of Working Example 19 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Working Example 20

The adhesive composition of Working Example 20 was obtained by the same method as that described in Working Example 1 , except that (a2) was used instead of (a1 ), 100 g (d ) were used instead of the 50 g (d ), 10 g (b1 ) and 10 g (b2) were used instead of the 5 g (b1 ), and 8 g (d1 ) were used instead of the 5 g (d"i )

The adhesive composition of Working Example 20 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 3

Table 3

b) Adhesion with respect to polyethylene, unit kgf/25 mm c) Adhesion with respect to polypropylene, unit kgf/25 mm

Comparison Example 8

The adhesive composition of Comparison Example 8 was

made by the same method as in Working Example 1 , except that (a2) was used instead of (a1 ), and (b1 ) was not used at all

The adhesive composition of Comparison Example 8 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 4

Comparison Example 9

The adhesive composition of Comparison Example 9 was made by the same method as in Working Example 1 , except that (a2) was used instead of (a1 ), 100 g (d ) were used instead of 50 g (d ), and (b1 ) was not used at all

The adhesive composition of Comparison Example 9 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 4

Comparison Example 10

The adhesive composition of Comparison Example 10 was made by the same method as in Working Example 1 , except that (a2) was used instead of (a1 ), and (d ), (b1 ), and (d1 ) were not used at all The adhesive composition of Comparison Example 10 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 4

Comparison Example 11

The adhesive composition of Comparison Example 11 was made by the same method as in Working Example 1 , except that (a2) was used instead of (a1 ), (d ) was not used at all, and 0 5 g (d1 ) was used instead of the 5 g (d1 )

The adhesive composition of Comparison Example 11 was evaluated by the same method as that descπbed in Working Example 1 and the results are shown in Table 4

Comparison Example 12

The adhesive composition of Comparison Example 12 was made by the same method as in Working Example 1 , except that (a2) was used instead of (a1 ), (d ) was not used at all, 10 g (b2) were used instead of the 5 g (b1 ), and 1 g (d1 ) was used instead of the 5 g (d1 )

The adhesive composition of Comparison Example 12 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 4 Comparison Example 13

The adhesive composition of Comparison Example 13 was made by the same method as in Working Example 1 , except that (a2) was used instead of (a1 ), (d ) was not used at all, 5 g (b2) were used

instead of the 5 g (b1 ), and 0 5 g (d1 ) was used instead of the 5 g (d1 )

The adhesive composition of Comparison Example 13 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 4

Comparison Example 14

The adhesive composition of Comparison Example 14 was made by the same method as in Working Example 1 , except that (a2) was used instead of (a1 ), (d ) was not used at all, 10 g (b2) were used instead of the 5 g (b1 ), and 1 g (d1 ) was used instead of the 5 g (d1 )

The adhesive composition of Comparison Example 14 was evaluated by the same method as that described in Working Example 1 and the results are shown in Table 4

Table 4

Effects of the Invention

A novel adhesive composition with improved adhesion can be provided by this invention, this adhesive composition is especially ideal for use with olefin and acrylic plastics

Claims

What is claimed

(1 ) An adhesive composition which comprises

- Sι(R¹)(OR²)₂ (I)

(where R¹ and R² are C1 -20 hydrocarbon groups which may contain substituents and may be the same or different from each other) 100 parts by weight,

(B) an epoxy resin shown by the general formula

-R³-0- (II)

(where R³ C2-4 alkylene group) 1 -50 parts by weight per 100 parts by weight (C),

(C) an epoxy resin other than the epoxy resin (B) 5-200 parts by weight per 100 parts by weight (A),

(D) a silanol condensation catalyst 0 1-20 parts by weight per

100 parts by weight (A),

(E) epoxy resin hardener 0 1-20 parts by weight per 100 parts by weight ((B)+(C)), and

(F) a silicon compound with a cross-linkable group shown by the general formula

-Sι(OR⁴)₃ (III)

(where R⁴ C1 -20 hydrocarbon group which may contain substituents), at a weight ratio ((A)+(B)+(C))/(F)=100/0 1-100/20

(2) The adhesive composition in accordance with Claim (1 ) in which the mam chain of the rubber organic polymer (A) has at least 1 unit shown by the general formula

-R⁵-0- (IV)

(where R⁵ C2-4 bivalent alkylene group)

(3) The adhesive composition in accordance with Claim (1 ) or Claim (2) in which the number average molecular weight of the rubber organic polymer (A) is 2000-20000 and its viscosity is 500-25000 cps (23°C)

(4) The adhesive composition in accordance with any of Claims (1 )-(3) in which the epoxy resin (C) is of the bisphenol A type

(5) The adhesive composition in accordance with any of Claims (1 )-(4) in which the silicon compound (F) is shown by the general formula

R⁶-R⁷-Sι(OR⁴)₃ (V)

(where R⁶ is an ammo group (which may be replaced with a C1-4 alkyl group containing an ammo group), R⁷ is a C1-4 bivalent alkylene group, and R⁴ is a C1-20 hydrocarbon group which may also have substituents)

(6) The adhesive composition in accordance with any of Claims (1 )-(5) to which moisture is also added

(7) The adhesive composition in accordance with Claim (6) in which the quantity of moisture added is 0 05-1 0 part by weight per 100 parts by weight of (A)

(8) The adhesive composition in accordance with any of Claims (1 )-(7) for adhering polyolefin plastics and acrylic plastics

(9) The adhesive composition of a two-liquid type in which, in an adhesive composition in accordance with any of Claims (1 )-(8), one composition includes the rubber organic polymer (A), the epoxy resin hardener (E), and the silicon compound (F), and the other includes the epoxy resin (B), the epoxy resin (C), and the silanol condensation catalyst (D)

(10) A combination of a rubber organic polymer (A), an epoxy resin (B), an epoxy resin (C), a silanol condensation catalyst (D), an epoxy resin hardener (E), and a silicon compound (F) for forming any of the adhesive compositions in accordance with any of Claims (1 )-(9)