WO2010008154A2

WO2010008154A2 - Room temperature moisture curable hybrid resin, method of preparing the same and application thereof

Info

Publication number: WO2010008154A2
Application number: PCT/KR2009/003754
Authority: WO
Inventors: Tai-Woong Boo; Chun-Mi Kim; Yeun-Su Lim; Nam-Kyung Lee
Original assignee: Korea Bio-Gen Co., Ltd
Priority date: 2008-07-15
Filing date: 2009-07-09
Publication date: 2010-01-21
Also published as: WO2010008154A3

Abstract

Disclosed are a room temperature moisture-curable hybrid resin, a method of preparing the same and application thereof. More particularly, disclosed are a room temperature moisture- curable hybrid resin obtained by reacting a hydroxyl-terminated prepolymer or a polyether polyol having a weight average molecular weight of 8,000-60,000 with an isocyanatoalkylsilane compound, a room temperature moisture-curable hybrid resin obtained by reacting an isocyanate-terminated prepolymer with a sec-aminosilane compound, and methods of preparing the same. The room temperature moisture-curable hybrid resin has easily controllable viscosity to provide good workability, provides a polymer resin having a wide range of modulus and elongation characteristics derived therefrom, and may be provided with a wide spectrum of me¬ chanical and physical properties including increased elasticity of a cured resin. Therefore, the room temperature moisture-curable hybrid resin may be applied to sealants, adhesives, binders, coating agents, etc. for use in various industrial fields including construction, electric/electronic and automobile industries.

Description

ROOM TEMPERATURE MOISTURE CURABLE HYBRID RESIN, METHOD OF PREPARING THE SAME AND APPLICATION THEREOF

The present invention relates to a room temperature moisture-curable hybrid resin, a method of preparing the same and application thereof. More particularly, the present invention relates to a room temperature moisture-curable hybrid resin including a silicon compound introduced thereto, which may be applied to sealants, adhesives, binders, coating agents, etc. for use in various industrial fields including construction, electric/electronic and automobile industries, a method of preparing the same and application thereof.

Silicone materials are hybrid materials having organic characteristics combined with inorganic characteristics. Although such silicone materials have excellent heat resistance, electrical insulation properties and weather resistance, they have poor plastering applicability, mechanical properties and adhesive properties and are expensive due to high-cost starting materials.

Therefore, many attempts have been made to develop novel hybrid functional polymers overcoming such shortcomings of silicone materials with organic polymers having excellent physical properties while maintaining advantages unique to silicone materials. For example, methods of blending or copolymerizing silicon compounds with general organoresins and introducing reactive silane compounds into the ends of organoresins have been suggested.

The resin obtained by one of the above methods is room temperature moisture-curable, and may be applied to sealants, adhesives, binders, coating agents, etc. for use in various industrial fields including construction, electric/electronic and automobile industries.

To make the room temperature moisture-curable hybrid resin obtained by one of the above methods applicable to sealants, adhesives, binders, coating agents, etc., it is required for the resin to have various properties tailored for particular use. For example, the resin is provide with low viscosity, good workability, elongation controllability depending on particular use, high elasticity, excellent adhesion to various materials, curing rate controllability, rapid tack-free characteristics, excellent mechanical and physical properties, or the like.

When the prepolymer of the resin is end-capped with an isocyanate group, the highly reactive isocyanate group may react with a hydroxyl, amine, carboxyl group, etc., so that it may be modified with various silane compounds having a reactive group, such as an amine group, with ease at the end. In addition, when the prepolymer is end-capped with a hydroxyl group, the end may be modified with various silane compounds having a reactive isocyanate group to provide a room temperature moisture-curable resin.

Under these circumstances, US Patent No. 3,632,557 discloses introduction of a primary or secondary aliphatic aminosilane into the prepolymer end-capped with an isocyanate group. Additionally, US Patent No. 4,645,816 discloses a composition of a room temperature moisture-curable resin obtained by introducing an organofunctional silane having one dialkoxy group and one active hydrogen atom to improve the elongation and elasticity.

In addition, US Patent No. 4,374,237 discloses a polymer resin composition having improved wet adhesion and obtained using a secondary aminosilane monomer having two trialkoxysilane groups. US Patent No. 4,474,933 discloses a method of preparing a room temperature moisture-curable resin using various primary and secondary difunctional aminosilanes as end cappers. US Patent No. 5,364,955 suggests a method of improving a cured elastomer in its flexibility by reducing the crosslinnking density thereof with N-alkoxysilylalkyl aspartic acid ester having a difunctional group and a sterically hindered amine group. However, since the above methods basically use aminosilanes, they entail urea bond formation, resulting in a significant increase in the viscosity of the resin and limited elongation.

Meanwhile, US Patent No. 6,197,912 discloses a method of preparing a room temperature moisture-curable resin by introducing various secondary aminoalkoxysilanes into various prepolymers end-capped with NCO.

In general, the above methods include reacting an equivalently excessive amount of polyisocyanate compounds with polyoxyalkylene diol compounds to obtain isocyanate-containing prepolymers.

However, the above methods result in formation of a large amount of urethane bonds in the resultant prepolymers. Particularly, urea bonds having higher coagulating property than urethane bonds are formed between aminosilane and isocyanate prepolymers, leading to a limitation in elongation. This is because urethane bonds and urea bonds have coagulating properties so that they may cause a drop in elongation in a cured sealant.

When preparing a room temperature moisture-curable resin using the isocyanate-terminated polyurethane prepolymer thus prepared, it is required to control the crosslinking density in the cured molecule to different levels, so that a room temperature moisture-curable hybrid polymer resin easily controllable in viscosity, elongation and modulus, having good physical properties and tailored for particular use and work may be obtained.

The room temperature moisture-curable hybrid polymer resins obtained by the above methods are generally high-modulus type polymer resins having good properties as adhesives and sealing agents for materials of electric/electronic and automobile industries.

Meanwhile, to allow such room temperature moisture-curable resins to be used as a sealing agent in the constructional application, one of their main applications, the cured sealing agent is required to have a good elongation. However, the polymer resins obtained by the above methods have a low elongation due to the urea and urethane bonds and show an increased viscosity, leading to poor workability.

To obtain a polymer resin having a low viscosity and high elongation by overcoming the above-mentioned problems, uses of a prepolymer of polyoxyalkylene polyol having a molecular weight as high as possible have been suggested, or various methods have been suggested for reducing or eliminating elongation-decreasing factors, such as urethane bonds and urea bonds in the resin. According to such methods, a hydroxyl group is introduced to the end of the prepolymer and the prepolymer is allowed to react with a silane having a highly reactive isocyanate group, or a modified silicone resin is prepared using a silane end-capped with mercapto and a catalyst.

Therefore, a high-molecular weight polyoxyalkylene is used to increase the molecular weight of the prepolymer. However, it is generally difficult to prepare a polyoxyalkylene polyol having a high molecular weight greater than 4,000 due to the side reactions of ring opening addition polymerization.

Under these circumstances, US Patent No. 3,971,751 discloses a method for preparing a polyether diol by reacting a hydroxyl group with sodium alkoxide and then with allyl chloride and dichloromethane.

According to the above method, it is suggested a method for preparing a silane-modified polyether polyol through the catalytic reaction between the ends of a polyether polyol having a weight average molecular weight of about 12,000 or higher and methyl dimethoxysilane. However, the method requires a high cost, and thus applications of the finished product are not cost-efficient. Moreover, since the reactive group participating in the curing is dimethoxy, it is not possible to improve the curability and adhesion. In brief, the above method provides improved elongation but other limited physical properties, resulting in a limitation in application of the resultant silane-modified polyether polyol. Additionally, it requires a long curing time and provides poor adhesion to PVC, etc.

In addition, the above method requires polymerization of polyoxyalkylene diol to increase the molecular weight of the polyoxyalkylene polyol to 12,000 or higher. However, preparation of the high-molecular weight polyoxyalkylene polyol is very complicated, requires a high cost, shows difficulty in controlling the molecular weight of the polyol, and tends to broaden the molecular weight distribution of the polyol.

US Patent No. 4,345,053 suggests that a room temperature moisture-curable silicone-terminated organic polymer is prepared by reacting a polyoxyalkylene diol, polyoxyalkylene triol or polyhydroxy polysulfide polyol with an organic polyisocyanate (i.e., diisocyanate) to form a polyurethane prepolymer, followed by end capping with an isocyanato organotrialkoxysilane. The resultant urethane bonds and urea bonds improve the heat stability and weather resistance of the prepolymer. However, the prepolymer has excessively high viscosity, poor workability and low elongation.

Further, US Patent No. 5,990,257 discloses a method for preparing a rapidly curable, non-brittle and elastic resin by reacting an equivalently excessive amount of polyether polyol having a high molecular weight and low unsaturation degree for decreasing viscosity with a diisocyanate component to form a high-molecular weight hydroxyl-terminated polyurethane prepolymer, which, in turn, is allowed to react with an isocyanato alkoxy functional silane, i.e., a trialkoxyfunctional silane, such as γ-isocyanato propyl-triethoxy silane or γ-isocyanato propyl-trimethoxy silane.

In addition, US Patent No. 5,608,304 discloses a method for preparing a high-molecular weight polyoxyalkylene polyol containing ether bonds alone and having a very low unsaturation degree. Also, it discloses a method for preparing a hydrolyzable silyl group-containing polyether compound by reacting the polyoxyalkylene polyol prepared through the above method with isocyanatoalkylalkoxysilane.

However, the resin or compound suggested in the above patent also has a limited resin structure, resulting in a limitation in controlling the elongation. Moreover, when applying the resin to sealants, gluing agents/adhesives or coating agents, it is difficult to impart adequate elongation characteristics.

As described above, according to the related art, commercially available polyalkoxyalkylene polyols having a molecular weight of at most 4,000 is allowed to react with an isocyanate compound to form a high-molecular weight isocyanate-terminated polyurethane prepolymer, which, in turn, is allowed to react with isocyanato alkylalkoxysilane having two or three hydrolyzable groups to obtain a room temperature curable polymer resin. Particularly, to obtain a high-elongation resin according to the related art, a polyoxyalkylene polyol having a high molecular weight of 8,000 or higher, specifically 12,000 or higher may be prepared and allowed to react directly with a silane compound. However, as mentioned above, preparation of such high-molecular weight polyols is difficult and needs a high cost. Moreover, the resultant resin has a good elongation but poor mechanical properties.

Therefore, controlling the crosslinking density in a cured molecule may be required to obtain a room temperature moisture-curable hybrid polymer resin having low viscosity, easily controllable elongation and good physical properties adequate for particular use and work.

In addition, according to the related art, a silane compound having two or three hydrolyzable groups is used alone to be bound to both ends of the prepolymer. Thus, the resultant polymer resin is a polymer resin both ends of which are bound to a silane having three hydrolyzable groups or to a silane having two hydrolyzable groups. In brief, only the preparation of a polymer resin, both ends of which are the same is allowed according to the related art. It is not possible to obtain a polymer resin both ends of which are of different types, i.e., a heterogeneous (different types of) silane-bound polymer resin, for example, a polymer resin, one end of which is bound to a silane having three hydrolyzable groups and the other end of which is bound to a silane having two hydrolyzable groups.

In addition, even when the moisture-curable resins according to the related art are mixed with each other, a moisture-curable polymer blend having limited physical properties is obtained due to a fundamental limitation in functional spectra of polymers. Moreover, additional work, complexity and cost are generated to perform the blending, and the resultant polymer may have non-uniform quality.

An object of the present invention is to provide a room temperature moisture-curable hybrid resin obtained by introducing silane compounds having various hydrolyzable groups to various resins and having controllable physical properties, including elongation, elasticity and strength, to be applied to various applications. Further, an object of the present invention is to provide a method for preparing the resin and use thereof.

To achieve the object of the present invention, the present invention provides a room temperature moisture-curable hybrid resin represented by Chemical Formula I:

[Chemical Formula I]

wherein

R_a and R_bare the same or different and each represents a linear or branched (C1-C6)alkylene;

R_c and R_dare the same or different and each represents a linear or branched (C1-C4)alkyl;

R_e and R_fare the same or different and each represents a linear or branched (C1-C6)alkyl;

W is

or

;

A represents a substituent having a weight average molecular weight of 5,000-60,000 and is selected from the group consisting of polyacrylate, polyether, polyester, polyurethane, polyoxyalkylene, polyolefin, polyorganosiloxane and a combination thereof;

B represents a substituent having a weight average molecular weight of 300-25,000 and is selected from the group consisting of reaction mixtures between an isocyanate compound and any one compound selected from polyether polyol, polyester polyol, polyurethane polyol, polyoxyalkylene polyol, organosiloxane compound and a combination thereof;

Z' and Z" are the same or different and each represents a linear (C1-C4)alkyl or phenyl; and

each of h and i is an integer selected from 0 to 3, and a+b is an integer of 0 to 6.

More particularly, Chemical Formula I includes a room temperature moisture-curable hybrid resin represented by Chemical Formula 1 or Chemical Formula 10.

Thus, there is provided room temperature moisture-curable hybrid resin represented by Chemical Formula 1:

[Chemical Formula 1]

Wherein

R' and R are the same or different, and each represents a linear or branched (C1-C6)alkylene;

R₁' and R₁ are the same or different, and each represents a (C1-C4)alkyl;

X' and X are the same or different, and each represents a linear or branched (C1-C6)alkyl; and

each of m and n is a number selected from 0-3 with the proviso that m+n is an integer of 0-6.

In another aspect, there is provided a method for preparing a room temperature moisture-curable hybrid resin represented by Chemical Formula 1, which includes reacting a hydroxyl-terminated prepolymer represented by Chemical Formula 2 with at least one isocyanatoalkyl silane compound represented by Chemical Formula 3 by simultaneous mixing or continuous introduction:

[Chemical Formula 1]

[Chemical Formula 2]

HO-A-OH

[Chemical Formula 3]

wherein

R represents a linear or branched (C1-C6)alkylene;

R' and R represent substituents derived from R, and are identical or different;

R₁ represents a linear or branched (C1-C4)alkyl;

R₁' and R₁ represent substituents derived from R₁, and are identical or different;

X represents a linear or branched (C1-C6)alkyl;

X' and X represent substituents derived from X, and are identical or different; and

l, m and n independently represent an integer selected from 0 to 3, and m+n represents an integer from 0 to 6.

In still another aspect, there is provided a sealant obtained using the above room temperature moisture-curable hybrid resin.

In still another aspect, there is provided a sealing composition including the above sealant.

In yet another aspect, there are provided an adhesive including the above room temperature moisture-curable hybrid resin and gluing agent including the above room temperature moisture-curable hybrid resin.

Hereinafter, the embodiments of the present invention will be described in detail.

The room temperature curable polymer resin disclosed herein is formed by introducing silicon compounds into both ends thereof, wherein various silane compounds having the same or different hydrolyzable groups are allowed to react with each end of the resin simultaneously (or by mixing) or successively. In this manner, the same or different silane compounds bound to both ends of the resin control the crosslinking density or coagulating degree of the resin upon curing.

1. Room Temperature Moisture-curable Hybrid Resin and Preparation Thereof

The room temperature moisture-curable hybrid resin represented by Chemical Formula 1 is obtained by reacting a hydroxyl-terminated prepolymer represented by Chemical Formula 2 with at least one isocyanatoalkyl silane compound represented by Chemical Formula 3.

Reaction Scheme 1 illustrates one embodiment of the preparation of the room temperature moisture-curable resin.

[Reaction Scheme 1]

wherein

R represents a linear or branched (C1-C6)alkylene;

R' and R represent substituents derived from R, and are identical or different;

R₁ represents a linear or branched (C1-C4)alkyl;

X represents a linear or branched (C1-C6)alkyl;

1) Preparation of Hydroxyl-Terminated Prepolymer

The hydroxyl-terminated prepolymer useful for preparing the room temperature moisture-curable resin disclosed herein is represented by Chemical Formula 2:

[Chemical Formula 2]

HO-A-OH

wherein

the backbone, prepolymer A represents a polymer selected from the group consisting of polyacrylate, polyether, polyester, polyurethane, polyoxyalkylene, polyolefin, polyorganosiloxane and a combination thereof. Particularly, A represents polyoxyalkylene, polyether or polyurethane. Additionally, A may have a weight average molecular weight of 5,000-60,000, specifically 5,000-50,000 and more specifically 5,000-45,000. If the resin has a molecular weight less than 5,000, it has poor physical properties. On the other hand, if the resin has a molecular weight greater than 60,000, it has poor processability.

The hydroxyl-terminated prepolymer represented by Chemical Formula 2 may include polyoxyalkylene diols or polyetherpolyols having a weight average molecular weight of 8,000 or higher, particularly 12,000 or higher. In this case, a silane compound having hydrolyzable groups may be bound directly to the high-molecular weight hydroxyl-terminated prepolymer without forming a separate prepolymer through the reaction with a diisocyanate compound.

The above-described hydroxyl-terminated polyurethane prepolymer may be prepared by a reaction between a polyol and a polyisocyanate.

In addition, when preparing the hydroxyl-terminated polyurethane prepolymer, the polyol reactant component is used in an equivalently excessive amount as compared to the polyisocyanate component so that the resultant prepolymer is end-capped with hydroxyl groups.

Therefore, in order to obtain an active hydroxyl group-terminated polyurethane for use in the resin disclosed herein, slight molar excess hydroxyl equivalents (-OH group) may be used as compared to isocyanate group equivalents of the polyisocyanate so that a hydroxyl-terminated prepolymer may be prepared.

Particularly, the molar ratio of isocyanate groups to hydroxyl groups (-NCO group/-OH group) may be 0.3-0.95, more particularly 0.5-0.85.

When the NCO/OH equivalent ratio is less than 0.3, it is not possible to form a prepolymer having an adequate range of molecular weights. On the other hand, when the NCO/OH equivalent ratio is greater than 0.95, formation of terminal active hydroxyl groups may be insufficient and terminal isocyanate groups may be easily formed.

When preparing the hydroxyl-terminated urethane prepolymer, a catalyst may be used depending on the reactivity of each reactant, and the reaction may be carried out at 60-90℃ for 2-8 hours.

The polyisocyanates that may be used to prepare the hydroxyl-terminated polyurethane prepolymer include diisocyanate or polyisocyanate components, which may be aromatic diisocyanates, aliphatic diisocyanates, cycloaliphatic diisocyanate, etc. Particular examples of the polyisocyanates include monomers, such as 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4-diphenylmethane diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4-diisocyanate, meta-tetramethylxylene diisocyanate, trimethylhexamethylene diisocyanate or hexamethylene diisocyanate and polymers and combinations thereof. More particularly, the polyisocyanates may include monomers, such as 2,4-toluene diisocyanate (2,4-TDI), 2,6-toluene diisocyanate (2,6-TDI), 4,4-diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), meta-tetramethylxylene diisocyanate (TMXDI), dicyclohexylmethane-4,4-diisocyanate (H12-MDI), trimethylhexamethylene diisocyanate (TMDI), or hexamethylene diisocyanate (HDI).

Meanwhile, the polyols that may be used to prepare the polyurethane prepolymer disclosed herein may include polyols having one, two or more hydroxyl groups, selected from the group consisting of polyether polyols, polyester polyols, polybutadiene diols, polyoxyalkylene diols, polyoxyalkylene triols, polytetraethylene glycol, polycaprolactone diols, polycaprolactone triols and combinations thereof. More particularly, the polyols that may be used herein includes polyether polyols or polyoxyalkylene diols. Herein, the polyoxyalkylene includes polyoxyethylene, polyoxypropylene or polyoxybutylene.

As suggested in the related art (US Patent Nos. 3,971,751, 5,990,257 and 5,608,304), the polyols that may be used to prepare the polyurethane polyol disclosed herein may have a very low unsaturation degree and a very high functionality.

In this context, the polyoxyalkylene diols or polyether polyols may be prepared using a metal complex catalyst for the polymerization of alkylene oxide in a manner generally known to those skilled in the art. The polyols may have a low terminal ethylenic unsaturation degree of 0.2 meq/g or less. Polyols with lower unsaturation are more advisable. Such polyols are ideal starting materials for preparing a high-molecular weight polyurethane prepolymer.

Since the polyols having a low unsaturation degree and high molecular weight may reduce the amount of hard segments used for increasing the chain length of the polyurethane prepolymer, it may significantly reduce the viscosity of the polyurethane prepolymer disclosed herein. Moreover, such a low unsaturation level of polyol allows the polyurethane prepolymer to have an increased molecular weight without any loss of functionality during the chain extension.

In view of this, the polyol may have a weight average molecular weight of 500-50,000, particularly 2,000-40,000. When the polyol has a weight average molecular weight less than 500, an increased amount of hard segments is used for the preparation of a high-molecular weight polyurethane prepolymer, resulting in production of a polymer having high viscosity and degradation of the processability thereof. On the other hand, it is difficult to prepare the polymer whose polyol component has a weight average molecular weight greater than 50,000. Moreover, in the latter case, the preparation of polymer is not cost-efficient and is commercially unacceptable.

2) Isocyanatoalkylsilane Compound

The Chemical formula 3 depicts isocyanatoalkyl hydrolyzable functional group-containing silane compounds bound to the hydroxyl-terminated prepolymer:

[Chemical Formula 3]

wherein

R represents a linear or branched (C1-C6)alkylene, particularly methylene or propylene;

R₁ represents a linear or branched (C1-C4)alkyl, particularly methyl or ethyl;

X represents a linear or branched (C1-C6)alkyl, particularly methyl, ethyl, propyl, butyl, and more particularly methyl; and

l represents an integer selected from 0 to 3, wherein when l=3, the compound is a silane compound having three hydrolyzable groups, when l=2, the compound is a silane compound having two hydrolyzable groups, when l=1, the compound is a silane compound having one hydrolyzable group, and when l=0, the compound is a silane compound having no hydrolyzable group.

The isocyanatoalkylsilane compound used herein provides a room temperature moisture-curable hybrid resin, in which 105-110 equivalents of the total silane equivalents used in at least one silane compound selected from the group consisting of silanes having three hydrolyzable groups (l=3), silanes having two hydrolyzable groups (l=2), silanes having one hydrolyzable group (l=1) and silanes having no hydrolyzable group (l=0) react with 100 equivalents of the hydroxyl groups of the hydroxyl-terminated prepolymer.

More particularly, the isocyanatoalkylsilane compound includes, based on 100 equivalents of the hydroxyl groups of the hydroxyl-terminated prepolymer, 0 or up to 100 equivalents of silanes wherein l=3, 0 or up to 100 equivalents of silanes wherein l=2, 0 or up to 50 equivalents of silanes wherein l=1, and 0 or up to 30 equivalents of silanes wherein l=0.

Herein, silanes wherein l=1 may be used in an amount corresponding to a silane equivalent of 0-50 equivalents, particularly 0-30 equivalents, and more particularly 0-20 equivalents, based on 100 equivalents of the hydroxyl groups of the hydroxyl-terminated prepolymer.

In addition, silanes wherein l=0 may be used in an amount corresponding to a silane equivalent of 0-30 equivalents, particularly 0-20 equivalents, and more particularly 0-10 equivalents, based on 100 equivalents of the hydroxyl groups of the hydroxyl-terminated prepolymer. In the case of a prepolymer having three hydroxyl groups, it is possible to control the crosslinking density through the binding of the silanes having different hydrolyzable functional groups as described above.

In other words, the silane compounds that may be used herein include at least one silane compound selected from silane compounds having three hydrolyzable groups, silane compounds having two hydrolyzable groups, silane compounds having one hydrolyzable groups and silane compounds having no hydrolyzable groups. The silane compounds are introduced simultaneously or successively to the hydroxyl-terminated prepolymer and are allowed to react with the prepolymer, wherein the total silane equivalents are in excess of the hydroxyl equivalents of the prepolymer by 5-10%. That is, the total silane equivalents are 105-110 equivalents based on 100 equivalents of the hydroxyl groups of the hydroxyl-terminated prepolymer. In this manner, it is possible to obtain a uniform room temperature moisture-curable hybrid resin with various grades tailored for particular use.

Therefore, the room temperature moisture-curable hybrid resin may have a controlled viscosity, elongation, elasticity, strength, modulus (low/middle/high modulus) depending on the mixing ratio and types of the silane compounds used therein, so that it may be used as a binder for sealants, sealing agents, adhesives, gluing agents, coating agents, or the like.

Particular examples of the isocyanatolakyl silane compounds having various hydrolyzable groups are selected from the group consisting of γ-isocyanato propyl trimethoxysilane, γ-isocyanato propyl methyldimethoxysilane, γ-isocyanato propyl dimethylmethoxysilane, γ-isocyanato propyl trimethylsilane, γ-isocyanato propyl triethoxysilane, γ-isocyanato propyl methyldiethoxysilane, γ-isocyanato methyl dimethylethoxysilane, α-isocyanato methyl trimethoxysilane, α-isocyanato methyl dimethoxymethylsilane, α-isocyanato methyl methoxydimethylsilane, α-isocyanato methyl trimethylsilane, α-isocyanato methyl triethoxysilane, α-isocyanato methyl diethoxymethylsilane, α-isocyanato methyl ethoxydimethylsilane and combinations thereof. The alpha type silanes have a higher hydrolysis rate than the gamma type silanes. Thus, it is possible to control the curing rate using the above silane compounds in an adequate ratio.

3) Preparation of Room Temperature Moisture-curable Hybrid Resin

The room temperature moisture-curable hybrid resin disclosed herein may be obtained by reacting the hydroxyl-terminated prepolymer prepared as described above (having active hydrogen atoms in the form of hydroxyl groups) with at least one of the above-listed isocyanatoalkyl silane compounds simultaneously (by mixing) or continuously in such a manner that the total silane equivalents are in excess of the hydroxyl equivalents by about 5%-10%.

The reaction is carried out under atmospheric pressure in a moisture-free condition. Particularly, a moisture-free condition is required for preventing the hydrolysis of the hydrolyzable silane compounds. The reaction may be performed at a temperature of 60-90℃ for 4-8 hours. The reaction may be performed in the presence of a catalyst but the catalyst may be introduced in a minimized amount depending on the progress of the reaction.

The completion of the reaction may be analyzed by standard titration (ASTM 2572-87) and infrared analysis (FT-IR). The reaction may be completed when any residual NCO groups are not monitored.

The room temperature moisture-curable polymer resins, obtained after the reaction of the hydroxyl-terminated prepolymer prepared as described above with the isocyanatoalkylsilane compounds, may be classified into the following 10 types of resins depending on the number of hydrolyzable groups bound to the ends of the resins, but are not limited thereto.

The room temperature moisture-curable hybrid resins disclosed herein may include resins both ends of which are the same hydrolyzable groups, or resins both ends of which are different hydrolyzable groups. For example, the room temperature moisture-curable hybrid resin may be at least one selected from the group consisting of: resins both ends of which are hydrolyzable trifunctional silanes (m=3 and n=3 in Chemical Formula 1); resins, one end of which is a hydrolyzable trifunctional silane and the other end of which is a hydrolyzable difunctional silane (m=3 and n=2 in Chemical Formula 1); resins, one end of which is a hydrolyzable trifunctional silane and the other end of which is a hydrolyzable monofunctional silane (m=3 and n=1 in Chemical Formula 1); resins, one end of which is a hydrolyzable trifunctional silane and the other end of which is a non-hydrolyzable silicon compound (m=3 and n=0 in Chemical Formula 1); resins both ends of which are hydrolyzable difunctional silanes (m=2 and n=2 in Chemical Formula 1); resins, one end of which is a hydrolyzable difunctional silane and the other end of which is a hydrolyzable monofunctional silane (m=2 and n=1 in Chemical Formula 1); resins, one end of which is a hydrolyzable difunctional silane and the other end of which is a non-hydrolyzable silicon compound (m=2 and n=0 in Chemical Formula 1); resins both ends of which are hydrolyzable monofunctional silanes (m=1 and n=1 in Chemical Formula 1); resins, one end of which is a hydrolyzable monofunctional silane and the other end of which is a non-hydrolyzable silicon compound (m=1 and n=0 in Chemical Formula 1); resins both ends of which are non-hydrolyzable silicon compounds (m=0 and n=0 in Chemical Formula 1); and combinations thereof.

The ten types of resins may be mixed in a suitable ratio depending on the particular types of silanes and proportions thereof. In this manner, the cured resin may have a controlled crosslinking density.

Meanwhile, even when a silane compound having no hydrolyzable group at both ends thereof (m+n=0) is bound to the resin, a minimum degree of molecular cohesive force exists due to hydrogen bonding of urethane groups in the resin, so that the crosslinking density may be controlled.

The crosslinking density of each type of room temperature moisture-curable hybrid resin decreases in the above list order. However, the strength and adhesion of each resin also decrease along with the crosslinking density. Thus, the resin may have an adequate combination of properties depending on its particular use.

2. Application (Use)

Hereinafter, formulation of a one-part sealant or adhesive using the room temperature moisture-curable hybrid resin will be described. However, the use of the resin disclosed herein is not limited thereto.

When the room temperature moisture-curable hybrid resin is used for preparing a sealant, starting materials of the sealant may include a filler, a plasticizer, a thixotropic agent, an anti-sagging agent, an adhesion promoter, a water scavenger, a stabilizer and a curing catalyst.

The filler that may be used herein includes fumed silica, precipitated silica, treated calcium carbonate with a size of 0.07-4 ㎛ and reinforced carbon black (for improving the physical properties). The filler is used in a completely dried form containing no moisture. The filler may be used in an amount of 50-250 parts by weight based on 100 parts by weight of the resin. When the filler is used in an amount less than 50 parts by weight, it is not possible to sufficiently improve the physical properties. When the filler is used in an amount greater than 250 parts by weight, the resin has poor processability.

The plasticizer that may be used herein includes dioctyl phthalate (DOP), diisodecyl phthalate (DIDP), benzoflex type plasticizer, etc. The plasticizer may be used in an amount of 50-100 parts by weight based on 100 parts by weight of the resin.

The thixotropic agent or anti-sagging agent that may be used herein includes castor wax, fumed silica, treated clay, polyamides, etc. The thixotrophic agent or anti-sagging agent may be used in an amount of 1-10 parts by weight based on 100 parts by weight of the resin.

In addition, silane compounds may be used as the adhesion promoter or water scavenger. Particularly, the adhesion promoter that may be used herein includes N-aminoethyl-aminoprpyl trimethoxysilane. The water scavenger that may be used herein includes vinyltrimethoxysilane. The adhesion promoter or water scavenger may be used in an amount of 0.5-5 parts by weight based on 100 parts by weight of the resin, depending on the work condition and particular use.

As the additive for modifying the physical properties, 0-10 parts by weight, particularly 0-7 parts by weight, and more particularly 0-5 parts by weight of phenyltrimethoxysilane may be introduced to 100 parts by weight of the room temperature moisture-curable resin. The additive decreases the viscosity of the resin, resulting in improvement in workability, improves the storage stability of the resin, provides excellent elongation and thermal stability through the formation of a flexible network in a cured polymer, improves the storage stability of a sealant by functioning as a water scavenger, and allows control of the curing rate. The additive may be added preliminarily to the moisture-curable resin or may be introduced upon the formulation of a sealant.

In addition, as the curing catalyst, 0.01-10 parts by weight of dibutyltin diacetate, stannous octoate, dibutyltin dilaurate, etc. may be used and introduced based on 100 parts by weight of the resin. When the curing catalyst is used in an amount less than 0.01 parts by weight, the resin may be cured too slowly. When the curing catalyst is used in an amount greater than 10 parts by weight, excessive curing may occur, resulting in degradation of the storage stability.

Further, antioxidants and UV stabilizers, such as titanium dioxide (TiO₂) may be used depending on particular use. However, additives that may be used herein are not limited thereto. The antioxidants or UV stabilizers may be used in an amount of 0.2-3 parts by weight based on 100 parts by weight of the resin so as to improve the durability and weather resistance of the sealant.

The starting materials are processed as follows.

The plasticizer is introduced into an agitator and the filler is introduced thereto under agitation, and the materials are mixed uniformly. The stabilizer and the room temperature moisture-curable resin are introduced thereto, the temperature is controlled to 80℃, and the mixture is agitated vigorously under vacuum for 60-90 minutes. Then, the mixture is cooled to 50℃, the adhesion promoter, water scavenger or dehydrating agent, curing catalyst and other additives are added thereto and the resultant mixture is agitated vigorously for about 30 minutes. N₂ is introduced at any time to prevent the reaction mixture from being in contact with moisture.

The sealant obtained as described above is cured at 23℃ under a relative humidity of 50% for 2 weeks, and then is subjected to tests for determining physical properties.

In another embodiment of the present invention, there is provided a room temperature moisture-curable hybrid resin represented by Chemical Formula 10:

[Chemical Formula 10]

wherein

R₁₀' and R₁₀ represent a linear or branched (C1-C4)alkyl, and are identical or different;

Y' and Y represent a linear or branched (C1-C6)alkylene, and are identical or different;

Z' and Z represent a linear (C1-C4)alkyl or phenyl, and are identical or different;

T' and T represent a linear or branched (C1-C6)alkyl, and are identical or different; and

p and q independently represent an integer selected from 0 to 3, p+q represents an integer from 0 to 6.

In still another embodiment, there is provided a method for preparing a room temperature moisture-curable hybrid resin represented by Chemical Formula 10, which includes reacting an isocyanate-terminated prepolymer represented by Chemical Formula 20 with at least one sec-aminoalkyl silane compound represented by Chemical Formula 30 by simultaneous mixing or continuous introduction:

[Chemical Formula 10]

[Chemical Formula 20]

OCN-B-NCO

[Chemical Formula 30]

wherein

B represents a substituent having a weight average molecular weight of 300-25,000 and is selected from the group consisting of reactions mixtures between an isocyanate compound and any one compound selected from polyether polyol, polyester polyol, polyurethane polyol, polyoxyalkylene polyol, organosiloxane compound and a combination thereof;

R₁₀represents a linear or branched (C1-C4)alkyl;

R₁₀' and R₁₀ represent substituents derived from R₁₀, and are identical or different;

Y represents a linear or branched (C1-C6)alkylene;

Y' and Y represent substituents derived from Y, and are identical or different;

Z represents a linear (C1-C4)alkyl or phenyl derivative;

Z' and Z represent substituents derived from Z, and are identical or different;

T represents a linear or branched (C1-C6)alkyl;

T' and T represent substituents derived from T, and are identical or different; and

o, p and q independently represent an integer selected from 0 to 3, and p+q represents an integer from 0 to 6.

In still another embodiment, there is provided a sealant obtained using the above room temperature moisture-curable hybrid resin.

In still another embodiment, there is provided a sealing composition including the sealant.

In yet another embodiment, there are provided an adhesive including the above room temperature moisture-curable hybrid resin, and a gluing agent including the above room temperature moisture-curable hybrid resin.

The room temperature moisture-curable polymer resin disclosed herein is formed by introducing silicon compounds into both ends thereof, wherein various silane compounds having the same or different hydrolyzable groups are allowed to react with each end of the resin simultaneously (or by mixing) or successively. In this manner, the same or different silane compounds bound to both ends of the resin control the crosslinking density or coagulating degree of the resin upon curing.

10. Room Temperature Moisture-curable Hybrid Resin and Preparation Thereof

The room temperature moisture-curable hybrid resin represented by Chemical Formula 10 is obtained by reacting an isocyanate-terminated prepolymer represented by Chemical Formula 20 with at least one sec-aminoalkyl silane compound represented by Chemical Formula 30.

Reaction Scheme 10 illustrates one embodiment of the preparation of the room temperature moisture-curable resin.

[Reaction Scheme 10]

wherein

R₁₀represents a linear or branched (C1-C4)alkyl;

Y represents a linear or branched (C1-C6)alkylene;

Y' and Y represent substituents derived from Y, and are identical or different;

Z represents a linear (C1-C4)alkyl or phenyl derivative;

Z' and Z represent substituents derived from Z, and are identical or different;

T represents a linear or branched (C1-C6)alkyl;

10) Preparation of Isocyanate-terminated Prepolymer

The isocyanate-terminated prepolymer useful for preparing the room temperature moisture-curable resin disclosed herein is represented by Chemical Formula 20:

[Chemical Formula 20]

OCN-B-NCO

wherein

the backbone, prepolymer B represents a substituent selected from the group consisting of reactions mixtures between an isocyanate compound and any one compound selected from polyether polyol, polyester polyol, polyurethane polyol, polyoxyalkylene polyol, organosiloxane compound and a combination thereof. Additionally, B may have a weight average molecular weight of 300-25,000, specifically 500-20,000. If the resin has a molecular weight less than 300, it has poor physical properties. On the other hand, if the resin has a molecular weight greater than 25,000, it has poor processability.

The isocyanate-terminated prepolymer may be prepared by a reaction between a polyol and a polyisocyanate.

In addition, when preparing the isocyanate-terminated polyurethane prepolymer, the isocyanate component is used in an equivalently excessive amount as compared to the polyol reactant component so that the resultant prepolymer is end-capped with isocyanate groups.

Therefore, in order to obtain an isocyanate group-terminated prepolymer for use in the resin disclosed herein, slight molar excess isocyanate group equivalents may be used as compared to hydroxyl group equivalents of the polyol so that an isocyanate-terminated prepolymer may be prepared.

Particularly, the molar ratio (NCO/OH) of isocyanate groups to hydroxyl groups (-NCO group/-OH group) may be 1.1-3.0, more particularly 1.3-2.0.

When the NCO/OH equivalent ratio is less than 1.1, the prepolymer may have an excessively high molecular weight or the prepolymer may not be isocyanate-terminated. On the other hand, when the NCO/OH equivalent ratio is greater than 3.0, the viscosity of prepolymer may be too high to provide good workability.

When preparing the isocyanate-terminated prepolymer, a catalyst may be used depending on reactivity of each reactant, and the reaction may be carried out at 60-90℃ for 2-6 hours.

The isocyanate compounds that may be used to prepare the isocyanate-terminated prepolymer include diisocyanates or polyisocyanates component, which may be aromatic diisocyanates, aliphatic diisocyanates, cycloaliphatic diisocyanate, etc. Particular examples of the polyisocyanates include monomers, such as 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4-diphenylmethane diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4-diisocyanate, meta-tetramethylxylene diisocyanate, trimethylhexamethylene diisocyanate or hexamethylene diisocyanate and polymers and combinations thereof. More particularly, the polyisocyanates may include monomers, such as 2,4-toluene diisocyanate (2,4-TDI), 2,6-toluene diisocyanate (2,6-TDI), 4,4-diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), meta-tetramethylxylene diisocyanate (TMXDI), dicyclohexylmethane-4,4-diisocyanate (H12-MDI), trimethylhexamethylene diisocyanate (TMDI), or hexamethylene diisocyanate (HDI).

Meanwhile, the polyols that may be used to prepare the polyurethane prepolymer disclosed herein may include polyols having one, two or more hydroxyl groups, selected from the group consisting of polyether polyols, polyester polyols, polybutadiene diols, polyoxyalkylene diols, polyoxyalkylene triols, polytetraethylene glycol, polycaprolactone diols, polycaprolactone triols and combinations thereof. More particularly, the polyols that may be used herein includes polyether polyols, polyoxyalkylene diols or polyoxyalkylene triols. Herein, the polyoxyalkylene includes polyoxyethylene, polyoxypropylene or polyoxybutylene.

In addition, the polyol may have a weight average molecular weight of 300-25,000, particularly 500-20,000. When the polyol has a weight average molecular weight less than 300, an increased amount of hard segments is used for the preparation of a high-molecular weight polyurethane prepolymer, resulting in production of a gel-like polymer having an excessively high viscosity and degradation of the processability thereof. On the other hand, it is difficult to prepare the polyol polymer whose polyol component has a weight average molecular weight greater than 25,000. Moreover, in the latter case, the preparation of polyol polymer is not cost-efficient and is commercially unacceptable.

20) sec-Aminoalkylsilane Compound

Chemical formula 30 depicts sec-aminoalkylsilane compounds bound to the isocyanate-terminated prepolymer:

[Chemical Formula 30]

wherein

R₁₀represents a linear or branched (C1-C4)alkyl, particularly methyl or ethyl;

Y represents a linear or branched (C1-C6)alkylene, particularly propylene, methylpropylene or dimethylbutylene;

Z represents a linear (C1-C4)alkyl or phenyl, particularly methyl, ethyl, propyl, butyl or phenyl;

T represents a linear or branched (C1-C6)alkyl, particularly methyl, ethyl, propyl, butyl, and more particularly methyl; and

o represents an integer selected from 0 to 3, wherein when o=3, the compound is a silane compound having three hydrolyzable groups, when o=2, the compound is a silane compound having two hydrolyzable groups, when o=1, the compound is a silane compound having one hydrolyzable group, and when o=0, the compound is a silane compound having no hydrolyzable group.

The sec-aminoalkylsilane compound used herein provides a room temperature moisture-curable hybrid resin, in which 102-110 equivalents of the total silane equivalents used in at least one silane compound selected from the group consisting of silanes having three hydrolyzable groups (o=3), silanes having two hydrolyzable groups (o=2), silanes having one hydrolyzable group (o=1) and silanes having no hydrolyzable group (o=0) react with 100 equivalents of the isocyanate groups of the isocyanate-terminated prepolymer.

More particularly, the sec-aminoalkylsilane compound includes, based on 100 equivalents of the isocyanate groups of the isocyanate-terminated prepolymer, 0 or up to 100 equivalents of silanes wherein o=3, 0 or up to 100 equivalents of silanes wherein o=2, 0 or up to 50 equivalents of silanes wherein o=1, and 0 or up to 30 equivalents of silanes wherein o=0.

Herein, silanes wherein o=1 may be used in an amount corresponding to a silane equivalent of 0-50 equivalents, particularly 0-30 equivalents, and more particularly 0-20 equivalents, based on 100 equivalents of the isocyanate groups of the isocyanate-terminated prepolymer.

In addition, silanes wherein o=0 may be used in an amount corresponding to a silane equivalent of 0-30 equivalents, particularly 0-20 equivalents, and more particularly 0-10 equivalents, based on 100 equivalents of the isocyanate groups of the isocyanate-terminated prepolymer.

In other words, the silane compounds that may be used herein includes at least one silane compound selected from silane compounds having three hydrolyzable groups, silane compounds having two hydrolyzable groups, silane compounds having one hydrolyzable groups and silane compounds having no hydrolyzable groups. The silane compounds are introduced simultaneously or successively to the isocyanate-terminated prepolymer and are allowed to react with the prepolymer, wherein the total silane equivalent is in excess of the isocyanate equivalents of the prepolymer by 2-10%. That is, the total silane equivalents are 102-110 equivalents based on 100 equivalents of the isocyanate groups of the isocyanate-terminated prepolymer. In this manner, it is possible to obtain a uniform room temperature moisture-curable hybrid resin with various grades tailored for particular use.

Particular examples of the sec-aminoalkyl silane compounds having various hydrolyzable groups are disclosed in US Patent No. 6,197,912 and include: N-methyl-3-amino-2-methylpropyltrimethoxysilane, N-ethyl-3-amino-2-methylpropyltrimethoxysilane, N-ethyl-3-amino-2-methylpropyldiethoxymethylsilane, N-ethyl-3-amino-2-methylpropyltriethoxysilane, N-ethyl-3-amino-2-methylpropylmethyldimethoxysilane, N-butyl-3-amino-2-methylpropyltrimethoxysilane, 3-(N-methyl-2-amino-1-methyl-1-ethoxy)-propyltrimethoxysilane, N-ethyl-4-amino-3,3-dimethylbutyldimethoxymethylsilane, N-ethyl-4-amino-3,3-dimethylbutyltrimethoxysilane, bis-(3-trimethoxysilyl-2-methylpropyl)amine, N-(3'-trimethoxysilylpropyl)-3-amino-2-methylpropyltrimethoxysilane, N-butylaminopropyltrimethoxysilane, N-ethylaminoisobutyltrimethoxysilane, N-methylaminopropyltrimethoxysilane, N-phenylaminopropyltrimethoxysilane, 3-(N-allylamino)propyltrimethoxysilane, (cyclohexylaminomethyl)triethoxysilane, N-cyclohexylaminopropyltrimethoxysilane, N-ethylaminoisobutylmethyldiethoxysilane, (phenylaminomethyl)methyldimethoxysilane, N-phenylaminomethyltriethoxysilane, N-methylaminopropylmethyldimethoxysilane, or the like.

30) Preparation of Room Temperature Moisture-curable Hybrid Resin

The room temperature moisture-curable hybrid resin disclosed herein may be obtained by reacting the isocyanate-terminated prepolymer prepared as described above with at least one of the above-listed sec-aminoalkyl silane compounds simultaneously (by mixing) or continuously in such a manner that the total silane equivalents are in excess of the isocyanate equivalents by about 2%-10%.

The reaction is carried out under atmospheric pressure in a moisture-free condition. Particularly, a moisture-free condition is required for preventing the hydrolysis of the hydrolyzable silane compounds. The reaction may be performed at a temperature of 60-90℃ for 2-6 hours. The reaction may be performed in the presence of a catalyst but the catalyst may be introduced in a minimized amount depending on the progress of the reaction.

The completion of the reaction may be analyzed by standard titration (ASTM 2572-87) or infrared analysis (FT-IR). The reaction may be completed when any residual NCO groups are not monitored or the NCO content reaches 0.8% or lower.

The room temperature moisture-curable polymer resins, obtained after the reaction of the isocyanate-terminated prepolymer prepared as described above with the sec-aminoalkylsilane compounds, may be classified into the following 10 types of resins depending on the number of hydrolyzable groups bound to the ends of the resins, but are not limited thereto.

The room temperature moisture-curable hybrid resins disclosed herein may include resins both ends of which are the same silane compound, or resins both ends of which are different silanes. For example, the resins both ends of which are different silanes include a resin, one hydrolyzable group of which is methoxysilane and the other hydrolyzable group of which is ethoxysilane.

More particularly, the room temperature moisture-curable hybrid resin may be at least one selected from the group consisting of: resins both ends of which are hydrolyzable trifunctional silanes (p=3 and q=3 in Chemical Formula 10); resins, one end of which is a hydrolyzable trifunctional silane and the other end of which is a hydrolyzable difunctional silane (p=3 and q=2 in Chemical Formula 10); resins, one end of which is a hydrolyzable trifunctional silane and the other end of which is a hydrolyzable monofunctional silane (p=3 and q=1 in Chemical Formula 10); resins, one end of which is a hydrolyzable trifunctional silane and the other end of which is a non-hydrolyzable silicon compound (p=3 and q=0 in Chemical Formula 10); resins both ends of which are hydrolyzable difunctional silanes (p=2 and q=2 in Chemical Formula 10); resins, one end of which is a hydrolyzable difunctional silane and the other end of which is a hydrolyzable monofunctional silane (p=2 and q=1 in Chemical Formula 10); resins, one end of which is a hydrolyzable difunctional silane and the other end of which is a non-hydrolyzable silicon compound (p=2 and q=0 in Chemical Formula 10); resins both ends of which are hydrolyzable monofunctional silanes (p=1 and q=1 in Chemical Formula 10); resins, one end of which is a hydrolyzable monofunctional silane and the other end of which is a non-hydrolyzable silicon compound (p=1 and q=0 in Chemical Formula 10); resins both ends of which are non-hydrolyzable silicon compounds (p=0 and q=0 in Chemical Formula 10); and combinations thereof.

Meanwhile, even when a silane compound having no hydrolyzable group at both ends thereof (p+q=0) is bound to the resin, a minimum degree of molecular cohesive force exists due to hydrogen bonding of urethane groups in the resin, so that the crosslinking density may be controlled.

The crosslinking density of each type of room temperature moisture-curable hybrid resin decreases in the above list order. However, the elongation of each resin increases as the crosslinking density decreases. Thus, the resin may have an adequate combination of properties depending on its particular use.

20. Application (Use)

In addition, silane compounds may be used as the adhesion promoter or water scavenger. Particularly, the adhesion promoter that may be used herein includes N-aminoethyl-aminopropyltrimethoxysilane or N-aminoethyl-aminopropylmethyldimethoxysilane. The water scavenger that may be used herein includes vinyltrimethoxysilane. The adhesion promoter or water scavenger may be used in an amount of 0.5-5 parts by weight based on 100 parts by weight of the resin, depending on the work condition and particular use.

As the stabilizer, 0-10 parts by weight, particularly 0-7 parts by weight, and more particularly 0-5 parts by weight of phenyltrimethoxysilane may be introduced to 100 parts by weight of the room temperature moisture-curable resin. The stabilizer decreases the viscosity of the resin, resulting in improvement in workability, improves the storage stability of the resin, provides excellent elongation and thermal stability through the formation of a flexible network in a cured polymer, improves the storage stability of a sealant by functioning as a water scavenger, and allows control of the curing rate. The stabilizer may be added preliminarily to the moisture-curable resin or may be introduced upon the preparation of a sealant.

In addition, as the curing catalyst, 0.01-10 parts by weight of dibutyltin acetate, stannous octoate, dibutyltin dilaurate, etc. may be used and introduced based on 100 parts by weight of the resin. When the curing catalyst is used in an amount less than 0.01 parts by weight, the resin may be cured too slowly. When the curing catalyst is used in an amount greater than 10 parts by weight, excessive curing may occur, resulting in degradation of the storage stability.

The starting materials are processed as follows.

The room temperature moisture-curable hybrid resin disclosed herein has easily controllable viscosity and good workability. The hybrid resin may be provided with a wide spectrum of mechanical and physical properties, including different ranges of elongation and increased elasticity of a cured resin.

In addition, the room temperature moisture-curable hybrid resin disclosed herein has easily controllable crosslinking density and physical properties by blending various types of resins, including resins both ends of which are the same or different functional groups.

In addition, the room temperature moisture-curable hybrid resin is obtained by a simple process that allows easy introduction of various silane groups.

Further, the room temperature moisture-curable hybrid resin may be tailored for its particular use, when applied to sealants, adhesives, gluing agents, coating agents, etc.

Hereinafter, the examples and experiments of the invention will be described.

Example 1

(Polymer-1: Reaction of Each Silane Compound wherein R=propylene, R₁=methyl and l=3 or 2 with Polyurethane Prepolymer ? Preparation of Resin Blend (R', R=propylene and R₁', R₁=methyl) Containing Resin wherein m, n=3, Resin wherein m, n=2 and Resin wherein m=3, n=2)

To a 1,000 mL glass reactor equipped with a mechanical stirrer, heating mantle, thermometer, condenser and N₂ inlet, a vacuum pump was provided to apply vacuum.

Next, 300 g of low-unsaturation polyoxypropylene polyol (unsaturation degree: 0.2 meq/g or lower, hydroxyl value: 26-30, MW: 4,065, Lupranol D-4000E available from BASF) and 11.9 g of isophorone diisocyanate (IPDI) were introduced to the reactor in such a manner that NCO/OH ratio is 0.7, and were allowed to react with each other under agitation for 5 hours while maintaining the reaction temperature at 80-90℃.

When the reaction did not proceed any more as determined by observing the reaction state, 5 ㎕ of dibutyl tin dilaurate (DBTDL) as a reaction catalyst was introduced to the reaction mixture in portions to cause additional reaction. When no NCO content appears as determined by FT-IR, the reaction was terminated. Then, a vacuum of 30 mmHg was applied to the reaction mixture before cooling and the reaction mixture was agitated vigorously for 30 minutes to remove low-molecular weight volatile materials therefrom, thereby providing a polyurethane prepolymer having a weight average molecular weight of 13,500.

To the polyurethane prepolymer thus prepared, 5.5 g of isocyanatopropyl trimethoxysilane and 5.3 g of isocyanatopropyl methyl dimethoxysilane were gradually introduced thereto, in turn. While maintaining the reaction temperature at 70-80℃, the reaction was terminated when no NCO content appeared as determined by IR. After the completion of the reaction, a vacuum of 10 mmHg was applied to the reaction mixture. Then, the reaction mixture was agitated vigorously for about 30 minutes to remove unreacted low-molecular weight materials by distillation, and then cooled. After the reaction, a room temperature moisture-curable resin, both ends of which are end-capped with isocyanatoalkyl silane, was obtained and the resin had a viscosity of 24,000 cps and a weight average molecular weight of 13,890.

More particularly, the room temperature moisture-curable resin was a blend of a resin including the polyurethane prepolymer, both ends of which were end-capped with trimethoxysilane, a resin including the polyurethane prepolymer, both ends of which were end-capped with dimethoxysilane, and a resin including the polyurethane prepolymer, one end of which was end-capped with trimethoxysilane and the other end of which was end-capped with dimethoxysilane.

Example 2

(Polymer-2: Reaction of Silane Compound wherein R=propylene, R₁=methyl and l=3 with Polyurethane Prepolymer ? Preparation of Resin wherein R', R=propylene, R₁', R₁=methyl and m, n=3)

A polyurethane prepolymer was obtained in the same manner as described in Example 1. Then, 11 g of isocyanatopropyl trimethoxysilane was gradually added thereto to react with the polyurethane prepolymer in the same manner as described in Example 1.

After the reaction, 300 g of a room temperature moisture-curable resin, both ends of which were end-capped with trimethoxysilane, was obtained and the resin had a viscosity of 19,230 cps and a weight average molecular weight of 13,700.

Example 3

(Polymer-3: Reaction of Each Silane Compound wherein R=propylene, R₁=methyl and l=3, 2, 1 or 0 with Polyurethane Prepolymer ? Preparation of Resin Blend (R', R=propylene and R₁', R₁=methyl) Containing Resin wherein m, n=3, Resin wherein m, n=2, Resin wherein m, n=1, Resin wherein m, n=0, Resin wherein m=3, n=2, Resin wherein m=3, n=1, Resin wherein m=3, n=0, Resin wherein m=2, n=1, Resin wherein m=2, n=0, and Resin wherein m=1, n=0)

A polyurethane prepolymer was obtained in the same manner as described in Example 1. Then, 5.5 g of isocyanatopropyl trimethoxysilane, 2.8 g of isocyanatopropyl methyldimethoxysilane, 1.48 g of isocyanatopropyl dimethylmethoxysilane, and 0.9 g of isocyanatopropyl trimethylsilane were mixed and added dropwise to the polyurethane prepolymer to perform a reaction in the same manner as described in Example 1.

After the reaction, a blend of resins, each including the polyurethane prepolymer whose ends were blocked with silanes having various hydrolyzable groups was obtained.

More particularly, the blend included: a resin, both ends of which were end-capped with hydrolyzable trifunctional silanes; a resin, one end of which was end-capped with a hydrolyzable trifunctional silane and the other end of which was end-capped with a hydrolyzable difunctional silane; a resin, one end of which was end-capped with a hydrolyzable trifunctional silane and the other end of which was end-capped with a hydrolyzable monofunctional silane; a resin, one end of which was end-capped with a hydrolyzable trifunctional silane and the other end of which was end-capped with a non-hydrolyzable silane; a resin, both ends of which were end-capped with hydrolyzable difunctional silanes; a resin, one end of which was end-capped with a hydrolyzable difunctional silane and the other end of which was end-capped with a hydrolyzable monofunctional silane; a resin, one end of which was end-capped with a hydrolyzable difunctional silane and the other end of which was end-capped with a non-hydrolyzable functional; a resin, both ends of which were end-capped with hydrolyzable monofunctional silanes; a resin, one end of which was end-capped with a hydrolyzable monofunctional silane and the other end of which was end-capped with a non-hydrolyzable functional silane; and a resin, both ends of which were end-capped with non-hydrolyzable silanes.

Example 4

(Polymer-4: Reaction of Silane Compound wherein R=propylene, R₁=methyl and l=2 and Silane Compound wherein R=methylene, R₁=methyl and l=2 with Polyether Polyol with MW of 12,000 ? Preparation of Resin Blend Containing Resin wherein R', R=propylene, R₁', R₁=methyl and m, n=2, Resin wherein R'=methylene, R=propylene, R₁', R₁=methyl and m, n=2, and Resin wherein R', R=methylene, R₁', R₁=methyl and m, n=2)

To 500 g of polyether polyol having a weight average molecular weight of 12,000, 9 g of isocyanatopropyl dimethoxylmethyl silane and 7.37 g of -isocyanatomethyl dimethoxymethylsilane were introduced sequentially and were allowed to react with the polyether polyol. After the reaction, about 515 g of a room temperature moisture-curable resin blend was obtained. The resin blend included: a resin, both ends of which were end-capped with isocyanatopropyl dimethoxymethylsilane; a resin, one end of which was end-capped with isocyanatopropyl dimethoxylmethylsilane and the other end of which was end-capped with isocyanatomethyl dimethoxymethylsilane; and a resin, both ends of which were end-capped with isocyanatomethyl dimethoxymethylsilane.

* Test Method

1) Viscosity

The viscosity of a room temperature moisture-curable resin was measured using a Brookfield DV-II viscometer under an ambient condition.

2) Physical Properties

[Table 1]

Examples 5-8

To determine the physical properties of the resins, cured polymer films were formed and their physical properties were compared in a simple manner.

To 100 g of each of the resins obtained from Examples 1 to 4, 5 g of N-aminoethyl-aminopropyltrimethoxysilane (DAS), and 1 g of dibutyl tin acetate (DBTAC) as a curing catalyst were introduced. Then, the mixture was agitated adequately and subjected to casting onto a teflon molding, followed by curing. The moldings were stored to perform curing in a chamber under the conditions of 23℃ and 50% relative humidity for 2 weeks, thereby providing films.

The films were tested by the above test methods and the results were shown in Table 2:

[Table 2]

As can be seen from the results of Table 2, the films of Examples 1-4 have various properties including controlled elongation properties, and thus may be tailored for various uses.

Examples 9-12

The resins obtained from Examples 1-4 were used to prepare sealants according to the formulation as shown in Table 3. Then, the sealants were characterized and the results were shown in Table 4.

Example 13

3 phr of phenyltrimethoxysilane (PTMS) was mixed with Polymer-2 as described in Example 2, and a sealant was prepared according to the formulation as shown in Table 3. Then, the sealant was characterized and the results were shown in Table 4.

[Table 3]

VTMS^*: vinyltrimethoxysilane

DAS^**: N-aminoethyl-aminopropyl trimethoxysilane

[Table 4]

As can be seen from the results of Table 4, elongation at break decreases as the number of hydrolyzable groups of a room temperature moisture-curable resin increases, due to an increase in crosslinking density. In Example 13, addition of PTMS under the same condition as other Examples helps improvement of elongation at break and Shore A hardness.

Example 14

(Polymer-10: Reaction of Each Silane Compound wherein Y=propylene, R₁₀=methyl and o=3 or 2 with Polyurethane Prepolymer ? Preparation of Resin Blend (Y', Y=propylene and R₁₀', R₁₀=methyl) Containing Resin wherein p, q=3, Resin wherein p, q=2 and Resin wherein p=3, q=2)

Next, 500 g of low-unsaturation polyoxypropylene polyol (unsaturation degree: 0.2 meq/g or lower, hydroxyl value: 26-30, MW: 4,065, Lupranol D-4000E available from BASF) and 42.6 g of isophorone diisocyanate (IPDI) were introduced to the reactor in such a manner that NCO/OH ratio was 1.5, and were allowed to react with each other under agitation for 4 hours while maintaining the reaction temperature at 70-80℃.

When the reaction did not proceed any more as determined by observing the reaction state, 5 ㎕ of dibutyltin dilaurate (DBTDL) as a reaction catalyst was introduced to the reaction mixture in portions to cause additional reaction. When the NCO content reached 0.8% or lower, the reaction was terminated.

Herein, ASTM D 2572 test method was used as a titration method for determining the free NCO%.

Then, a vacuum of 30 mmHg was applied to the reaction mixture before cooling and the reaction mixture was agitated vigorously for 30 minutes to remove low-molecular weight volatile materials therefrom, thereby providing a polyurethane prepolymer having a weight average molecular weight of 10,700.

To the polyurethane prepolymer thus prepared, 17 g of N-phenyl-gamma-aminopropyltrimethoxylsilane and 17 g of N-phenyl-gamma-aminopropylmethyldimethoxylsilane were gradually introduced thereto, in turn. While maintaining the reaction temperature at 70-80℃, the reaction was terminated when no NCO content appeared as determined by IR. After the completion of the reaction, a vacuum of 10 mmHg was applied to the reaction mixture. Then, the reaction mixture was agitated vigorously for about 30 minutes to remove unreacted low-molecular weight materials by distillation, and then cooled. After the reaction, 570 g of a room temperature moisture-curable resin including the polyurethane prepolymer, both ends of which were end-capped with sec-aminoalkyl silane, was obtained and the resin had a viscosity of 165,200 cps and a weight average molecular weight of 11,200.

Example 15

(Polymer-20: Reaction of Silane Compound wherein Y=propylene, R₁₀=methyl and o=3 with Prepolymer ? Preparation of Resin wherein Y', Y= propylene, R₁₀', R₁₀ = methyl and p, q=3)

A prepolymer was obtained in the same manner as described in Example 14. Then, 34 g of N-phenyl-gamma-aminopropyltrimethoxysilane was gradually added thereto to react with the prepolymer in the same manner as described in Example 14.

After the reaction, 570 g of a room temperature moisture-curable resin including the prepolymer, both ends of which were end-capped with trimethoxysilane, was obtained and the resin had a viscosity of 183,500 cps and a weight average molecular weight of 11,200.

Example 16

(Polymer-30: Reaction of Each Silane Compound wherein Y=propylene, R₁₀=methyl and o=3, 2, 1 or 0 with Prepolymer ? Preparation of Resin Blend (Y', Y=propylene and R₁₀', R₁₀=methyl) Containing Resin wherein p, q=3, Resin wherein p, q=2, Resin wherein p, q=1, Resin wherein p, q=0, Resin wherein p=3, q=2, Resin wherein p=3, q=1, Resin wherein p=3, q=0, Resin wherein p=2, q=1, Resin wherein p=2, q=0, and Resin wherein p=1, q=0)

A prepolymer was obtained in the same manner as described in Example 14. Then, 17 g of N-phenyl-gamma-aminopropyltrimethoxysilane, 8 g of N-butylaminopropylmethyldimethoxysilane, 4 g of N-phenyl-amniopropyldimethylmethoxysilane and 4 g of N-butyl-gamma-aminopropyltrimethylsilane were mixed and added dropwise to the prepolymer to perform a reaction in the same manner as described in Example 14.

After the reaction, a blend of resins, each including the prepolymer whose ends were blocked with silanes having various hydrolyzable groups was obtained.

Examples 17-19

The resins obtained from Examples 14-16 were used to prepare sealants according to the formulation as shown in Table 5. Then, the sealants were characterized and the results were shown in Table 6.

Example 20

3 phr of phenyltrimethoxysilane (PTMS) was mixed with Polymer-20 as described in Example 15, and a sealant was prepared according to the formulation as shown in Table 5. Then, the sealant was characterized and the results were shown in Table 6.

[Table 5]

VTMS^*: vinyltrimethoxysilane

DAS^**: N-aminoethyl-aminopropyltrimethoxysilane

[Table 6]

As can be seen from the results of Table 6, elongation at break decreases as the number of hydrolyzable groups of a room temperature moisture-curable resin increases, due to an increase in crosslinking density. In Example 20, addition of PTMS under the same condition as other Examples helps improvement of elongation at break and viscosity, thereby providing good workability.

Claims

A room temperature moisture-curable hybrid resin represented by Chemical Formula I:

[Chemical Formula I]

wherein

R_a and R_bare the same or different and each represents a linear or branched (C1-C6)alkylene;

R_c and R_dare the same or different and each represents a linear or branched (C1-C4)alkyl;

R_e and R_fare the same or different and each represents a linear or branched (C1-C6)alkyl;

W is
or
;

A represents a substituent having a weight average molecular weight of 5,000-60,000 and is selected from the group consisting of polyacrylate, polyether, polyester, polyurethane, polyoxyalkylene, polyolefin, polyorganosiloxane and a combination thereof;

B represents a substituent having a weight average molecular weight of 300-25,000 and is selected from the group consisting of reaction mixtures between an isocyanate compound and any one compound selected from polyether polyol, polyester polyol, polyurethane polyol, polyoxyalkylene polyol, organosiloxane compound and a combination thereof;

Z' and Z" are the same or different and each represents a linear (C1-C4)alkyl or phenyl; and

each of h and i is an integer selected from 0 to 3, and a+b is an integer of 0 to 6.
The room temperature moisture-curable hybrid resin according to claim 1, which includes a room temperature moisture-curable hybrid resin represented by Chemical Formula 1 or Chemical Formula 10:

[Chemical Formula 1]

wherein

A represents a substituent having a weight average molecular weight of 5,000-60,000 and is selected from the group consisting of polyacrylate, polyether, polyester, polyurethane, polyoxyalkylene, polyolefin, polyorganosiloxane and a combination thereof;

R' and R represent a linear or branched (C1-C6)alkylene, and are identical or different;

R₁' and R₁ represent a linear or branched (C1-C4)alkyl, and are identical or different;

X' and X represent a linear or branched (C1-C6)alkyl, and are identical or different; and

m and n independently represent an integer selected from 0 to 3, and m+n represents an integer from 0 to 6.

[Chemical Formula 10]

wherein

B represents a substituent having a weight average molecular weight of 300-25,000 and is selected from the group consisting of reactions mixtures between an isocyanate compound and any one compound selected from polyether polyol, polyester polyol, polyurethane polyol, polyoxyalkylene polyol, organosiloxane compound and a combination thereof;

R₁₀' and R₁₀ represent a linear or branched (C1-C4)alkyl, and are identical or different;

Y' and Y represent a linear or branched (C1-C6)alkylene, and are identical or different;

Z' and Z represent a linear (C1-C4)alkyl or phenyl, and are identical or different;

T' and T represent a linear or branched (C1-C6)alkyl, and are identical or different; and

p and q independently represent an integer selected from 0 to 3, and p+q represents an integer from 0 to 6.
The room temperature moisture-curable hybrid resin according to claim 2, which is a room temperature moisture-curable hybrid resin represented by Chemical Formula 1, obtained by reacting a hydroxyl-terminated prepolymer represented by Chemical Formula 2 with at least one isocyanatoalkylsilane compound represented by Chemical Formula 3:

[Chemical Formula 1]

[Chemical Formula 2]

HO-A-OH

[Chemical Formula 3]

wherein

A represents a substituent having a weight average molecular weight of 5,000-60,000 and is selected from the group consisting of polyacrylate, polyether, polyester, polyurethane, polyoxyalkylene, polyolefin, polyorganosiloxane and a combination thereof;

R represents a linear or branched (C1-C6)alkylene;

R' and R represent substituents derived from R, and are identical or different;

R₁ represents a linear or branched (C1-C4)alkyl;

R₁' and R₁ represent substituents derived from R₁, and are identical or different;

X represents a linear or branched (C1-C6)alkyl;

X' and X represent substituents derived from X, and are identical or different; and

l, m and n independently represent an integer selected from 0 to 3, and m+n represents an integer from 0 to 6.
The room temperature moisture-curable hybrid resin according to claim 2, which is a room temperature moisture-curable hybrid resin represented by Chemical Formula 10, obtained by reacting an isocyanate-terminated prepolymer represented by Chemical Formula 20 with at least one sec-aminoalkylsilane compound represented by Chemical Formula 30:

[Chemical Formula 10]

[Chemical Formula 20]

OCN-B-NCO

[Chemical Formula 30]

wherein

B represents a substituent having a weight average molecular weight of 300-25,000 and is selected from the group consisting of reactions mixtures between an isocyanate compound and any one compound selected from polyether polyol, polyester polyol, polyurethane polyol, polyoxyalkylene polyol, organosiloxane compound and a combination thereof;

R₁₀represents a linear or branched (C1-C4)alkyl;

R₁₀' and R₁₀ represent substituents derived from R₁₀, and are identical or different;

Y represents a linear or branched (C1-C6)alkylene;

Y' and Y represent substituents derived from Y, and are identical or different;

Z represents a linear (C1-C4)alkyl or phenyl derivative;

Z' and Z represent substituents derived from Z, and are identical or different;

T represents a linear or branched (C1-C6)alkyl;

T' and T represent substituents derived from T, and are identical or different; and

o, p and q independently represent an integer selected from 0 to 3, and p+q represents an integer from 0 to 6.
A sealant obtained using the room temperature moisture-curable hybrid resin according to any one of claims 1 to 4.
The sealant according to claim 5, which further comprises phenyltrimethoxysilane or phenyltriethoxysilane in an amount of 0.01-10 parts by weight based on 100 parts by weight of the room temperature moisture-curable hybrid resin.
A sealing composition comprising the sealant according to claim 5.
An adhesive comprising the room temperature moisture-curable hybrid resin according to any one of claims 1 to 4.
A gluing agent comprising the room temperature moisture-curable hybrid resin according to any one of claims 1 to 4.