JPS581712B2 - Pressure sensitive adhesive composition for PVC - Google Patents

Description

Detailed Description of the Invention This invention is applicable to polyvinyl chloride molded products containing low-molecular plasticizers such as dioctyl phthalate, dibutyl phthalate, and diindecyl phthalate, such as sheets, films, tapes, plates, and wall materials. The present invention relates to an acrylic pressure-sensitive adhesive composition for vinyl chloride suitable for adhering to adherends.

Conventionally, when bonding polyvinyl chloride molded products containing low-molecular plasticizers, adhesive tapes made by coating a support with a pressure-sensitive adhesive composition mainly composed of rubber or synthetic resin have been used. However, these may have insufficient initial adhesion, or the low-molecular plasticizer in the molded product may orally migrate into the adhesive composition, resulting in poor adhesive properties over time, especially aggregation. The drawback was that the power was significantly reduced.

As a result of intensive studies in light of these circumstances, the inventors of the present invention discovered an addition polymer obtained by using a specific acrylic polymer and further adding a specific ethylenically unsaturated monomer to this polymer. We learned that when polymerized polymers are used as the polymer component of adhesives, polyvinyl chloride molded products containing low-molecular plasticizers can be firmly adhered to adherends, and the deterioration of adhesive properties after oral administration can be greatly suppressed. , which led to the completion of this invention.

That is, this invention provides a pressure-sensitive adhesive composition for PVC that is applied to polyvinyl chloride molded products such as sheets, films, tapes, boards, wall materials, etc., containing a low-molecular plasticizer such as dioctyl phthalate, dibutyl phthalate, and diisodecyl phthalate. 50 to 9995% by weight of the main monomer consisting of an ester of acrylic acid or methacrylic acid and an aliphatic monohydric alcohol having 8 or less carbon atoms, a carbon-carbon compound having a polar group such as a carboxyl group, a hydroxyl group, or an amide group. 0.05 to 20% by weight of an unsaturated monomer having one double bond, and a vinyl monomer having one carbon-carbon double bond copolymerizable with these monomers O to 30 An acrylic polymer with an average molecular weight of about 100,000 or more by weight and adhesive at room temperature is used, and this acrylic polymer is further added with a homopolymer or copolymer having a glass transition point of 273.
Initial and post-oral compositions characterized in that the above composition contains as a polymer component an addition polymer obtained by addition polymerizing one or more ethylenically unsaturated monomers capable of producing a temperature of 100 °K or more. This invention relates to a pressure-sensitive adhesive composition for vinyl chloride that has excellent adhesive properties.

The acrylic polymer used in this invention has acrylic acid or methacrylic acid as main monomers and 8 carbon atoms.
Esters with the following aliphatic monohydric alcohols are used.

The reason why the number of carbon atoms in the aliphatic monohydric alcohol is set to be 8 or less is that if the number of carbon atoms is larger than this, the adhesiveness to polyvinyl chloride molded products will be significantly reduced orally.

Such main monomers include aliphatic monohydric alcohols whose alkyl groups include methyl, ethyl, butyl, isobutyl, hexyl, heptyl, octyl, inoctyl, 2-ethylhexyl, etc. Examples include esters of acrylic acid or methacrylic acid.

These are used in a proportion of 50 to 99.95% by weight based on the total monomers.

The unsaturated monomer having one carbon-carbon double bond and having a polar group used together with this main monomer is used to improve the adhesion of acrylic polymer to polyvinyl chloride molded products. Carboxyl group as a polar group,
Those that can impart polarity to acrylic polymers, such as hydroxyl groups, amide groups, nitrile groups, epoxy groups, substituted amino and amide groups (for example, N-hydroxyalkylamides and N-alkoxyalkylamides), can be widely used.

Specifically, acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, 2-hydroxyglopylacrylate, 2-methylhydroxyethyl acrylate, N
-N-dimethyl(ethyl)acrylate, bis-N-N
-dimethylaminoethyl maleate, (meth)acrylamide, N-methylolacrylamide, glycidyl (
Examples include meth)acrylate and acrylonitrile.

These unsaturated monomers having one carbon-carbon double bond and having a polar group are used in an amount of 0.05 to 20% by weight based on the total monomers.

In addition, if necessary, an optional monomer having one carbon-carbon double bond that can be copolymerized with the above-mentioned main monomer and an unsaturated monomer having one carbon-carbon double bond having a polar group. It is also possible to use vinyl monomers in an amount of O to 30% by weight based on the total monomers.

Examples include vinyl acetate, vinyl propionate, styrene and its derivatives, and vinyl chloride.

The acrylic polymer composed of such a monomer structure itself has adhesive properties at room temperature, but its molecular weight is said to be about 100,000 or more, preferably an average molecular weight of about 200,000 to 1,000,000. is necessary.

When the average molecular weight decreases below 100,000, the absorption rate and amount of the low-molecular plasticizer in the polyvinyl chloride molded product decreases, and the adhesive properties after oral administration, especially the cohesive strength, decrease significantly, making it unsuitable. It is.

Next, in this invention, it is important to add a specific ethylenically unsaturated monomer to the above-mentioned acrylic polymer, and this addition polymerization provides a large cohesive force that cannot be obtained with the acrylic polymer alone. Due to this effect of increasing cohesive force, even if the low-molecular plasticizer in the polyvinyl chloride molded product is transferred orally after adhesion, the decrease in cohesive force associated with this is almost negligible. The properties are made to have very good results.

On the other hand, if a homopolymer (or copolymer) is made alone from a specific ethylenically unsaturated monomer used for addition polymerization and blended with an acrylic polymer, no significant improvement in cohesive force is observed. Furthermore, the decrease in adhesive strength cannot be ignored, and a suitable pressure-sensitive adhesive composition for vinyl chloride cannot be obtained.

In addition, when a specific ethylenically unsaturated monomer used for addition polymerization is added during the synthesis of acrylic polymers and copolymerized at the same time, either adhesive strength, adhesive strength, or cohesive strength is extremely low. Therefore, an adhesive composition suitable for use with PVC cannot be obtained.

The specific ethylenically unsaturated monomer used for addition polymerization is one or more unsaturated monomers whose homopolymer or copolymer has a glass transition temperature of 273°K or higher, preferably 300°K or higher. It is a monomer.

Homopolymers or copolymers having a glass transition point lower than 273°K are not suitable because they do not sufficiently improve the cohesive force and impede the adhesive properties after oral administration.

In addition, among the two or more unsaturated monomers that can make the glass transition point of the copolymer 273°K or more, there are monomer mixtures that can make the glass transition point of the homopolymer of each monomer 273°K or more. Also included are mixtures of unsaturated monomers that can make the homopolymer have a glass transition point of 273°K or higher and unsaturated monomers that can make the homopolymer have a glass transition point lower than 273°K.

The latter monomer mixture may have a glass transition point of 273°K or more when formed into a copolymer depending on its composition ratio.

For example, n-butyl acrylate (2730K or less): methyl methacrylate (3000K or more) itaconic acid (30
A monomer mixture of -15:65:l5 (0°K or higher) is applicable because the glass transition point of the copolymer is 273°K or higher.

The inventors have discovered an unsaturated monomer selected from the group of styrene, vinyl acetate, acrylonitrile and methacrylonitrile, whose homopolymer can have a glass transition point of 300°K or more. The body?
Alternatively, an unsaturated monomer selected from the group of acrylic esters, methacrylic esters, or styrene derivatives whose glass transition temperature can be 273°K or higher (hereinafter, unsaturated monomers belonging to both groups are referred to as component A). have been found to be particularly suitable.

Specific examples of unsaturated monomers belonging to the latter group include cyclohexyl acrylate (289°K), methyl acrylate (279°K), and n-butyl methacrylate (293°K).
°K), N-N dimethylamine ethyl methacrylate (
289°K), hexadecyl methacrylate (288°K), hexadecyl methacrylate (288°K
K), 2-methoxyethyl methacrylate (286°K
), unsaturated monomers whose homopolymer glass transition temperature can be 273°K or higher, such as 4-butylstyrene (279°K), and 2-butyl methacrylate (3180K
), 3,3-dimethylbutyl methacrylate (318°
K), 3,3-dimethyl-2-butyl methacrylate (381°K), ethyl methacrylate (338°K)
, glycidyl methacrylate (319°K), isobornyl methacrylate (383°K), isobutyl methacrylate (326°K), isopropyl methacrylate (354°K), methyl methacrylate (3780K)
), phenyl methacrylate (378°K), n-propyl methacrylate (308°K), inbornyl acrylate (367°K), 4-tert-butylstyrene (403°K), 2,4-diisofuropyl Styrene (44 1°K), 2,5-dimethylstyrene (416°K), 3,4-diethylstyrene (38
2°K), 2-hydroxymethylstyrene (433°
There are unsaturated monomers whose homopolymers can have glass transition points of 3000K or higher, such as K), 4-methylstyrene (366°K), and 2-methylstyrene (366°K).

Among these unsaturated monomers belonging to the latter group, those whose homopolymer glass transition point can be 300°K or higher are desirable, and among these, methyl methacrylate is the most preferred.

In this invention, it is preferable to use one or more of these A component monomers selected from one or both of the two groups depending on the type of acrylic polymer; An unsaturated monomer (hereinafter referred to as component B monomer) which can be copolymerized with the monomer and whose copolymer has a glass transition point of 273°K or higher may be used together with the monomer.

Such B component monomers include unsaturated monomers whose homopolymers can have a glass transition point of 273°K or higher, such as acrylic acid, methacrylic acid, and itaconic acid, as well as n-butyl acrylate and ethyl acrylate. , the glass transition temperature of its homopolymers such as 2-ethylhexyl acrylate is 2.
One or more monomers used in general acrylic pressure-sensitive adhesives, such as unsaturated monomers with a temperature lower than 73°K, are used.

The amount of these component B monomers to be used is one of the factors that determines the glass transition point of the copolymer, so it may be determined appropriately according to the types of both component monomers A and B, taking this point into consideration. Generally not more than 95% by weight, preferably 3% by weight of the total monomers.
The content is preferably 0% by weight or less.

In this invention, when addition polymerizing such an ethylenically unsaturated monomer to an acrylic polymer that is sticky at room temperature, a solution polymerization method in which an organic solvent is included in the addition polymerization system or a bulk polymerization method that does not use any solvent is used. Any polymerization method may be employed.

According to the solution polymerization method, good polymerization workability is obtained, and the organic solvent used effectively acts as a chain transfer agent during the polymerization reaction to suppress excessive addition polymerization reaction, resulting in adhesiveness at room temperature. Very good results in preventing gelation during the polymerization reaction when the acrylic polymer has a high molecular weight to begin with, and in adjusting the molecular weight of the addition polymer and the homopolymer (or copolymer) that is partially formed with this polymer. to have.

Examples of such organic solvents are toluene, benzene,
xylene, hexane, heptane, n-octane, isooctane, ethyl acetate, acetone, methyl ethyl ketone,
Examples include methanol, ethanol, isopropanol, and the like.

Note that these organic solvents may be used as they are to form the acrylic polymer that is sticky at room temperature.

The amount of organic solvent used is usually 5 to 900 parts by weight, preferably 25 to 400 parts by weight, per 100 parts by weight of the acrylic polymer, which is sticky at room temperature.If this amount is too large, addition polymerization may occur. Since the amount of polymer produced decreases and a large amount of homopolymer is produced, the effects of the present invention cannot be obtained sufficiently.

In determining the amount to be used, consider the type of ethylenically unsaturated monomer, the ease of chain transfer of the organic solvent to the monomer radical, and the composition and molecular weight of the acrylic polymer, which is sticky at room temperature. It is better to take into account the type and amount of other polymerization initiators used.

For example, when vinyl acetate is used as the ethylenically unsaturated monomer, it is preferably used in an amount of usually 5 to 70 parts by weight per 100 parts by weight of the acrylic polymer. When used, the proportion is preferably 5 to 400 parts by weight.

In addition, it is generally preferable to use organic solvents such as ethyl acetate and benzene, which have small chain transfer constants, or to use a large amount of solvent for acrylic polymers with very high molecular weights; conversely, toluene, which has a large chain transfer constant, When using an organic solvent such as isopropanol, or when using an acrylic polymer with a relatively low molecular weight, it is better to reduce the amount of solvent used.

On the other hand, in such a bulk polymerization method that does not contain a solvent, an acrylic polymer that is sticky at room temperature and has the lowest possible molecular weight is selected, and when an acrylic polymer with a high molecular weight is used, an appropriate amount of acrylic polymer is added to the polymerization system. It is preferable to include a chain transfer agent to prevent gelation during polymerization and to prevent the addition polymerization reaction from proceeding excessively.

The above-mentioned chain transfer agents include a wide variety of conventionally known chain transfer agents such as thioglycol, thioglycolic acid, butyl mercaptan, and lauryl mercaptan.

The amount used may be about 0.01 to 0.1 part by weight, preferably about 0.03 to 0.6 part by weight, per 100 parts by weight of the ethylenically unsaturated monomer.

In such solution polymerization or bulk polymerization, the blending ratio of the acrylic polymer, which is sticky at room temperature, and the ethylenically unsaturated monomer is generally 100% of the acrylic polymer.
The amount of ethylenically unsaturated monomer is 5 to 200 parts by weight, preferably 10 to 150 parts by weight.

If this amount is too large, even if the cohesive force can be improved, the adhesive force will drop significantly.

Of course, the amount used depends on the composition or molecular weight of the acrylic polymer used, the type of ethylenically unsaturated monomer, and the amount of solution used to prevent gelation during the polymerization reaction and to prevent the addition polymerization reaction from proceeding too much. It should be determined appropriately depending on whether a polymerization method or a bulk polymerization method is adopted, and in the case of a solution polymerization method, the type of organic solvent used.
The optimum range varies considerably in various aspects.

Generally, when using an acrylic polymer with a high molecular weight, compared to when using an acrylic polymer with a low molecular weight, the above A component monomer other than vinyl acetate is used as the ethylenically unsaturated monomer. When using vinyl acetate as the same monomer, when using bulk polymerization, compared to when using solution polymerization, organic solvents with smaller chain transfer constants are used. When using a monomer with a large number of identifications, it is better to use a smaller amount of each ethylenically unsaturated monomer than when using a monomer with a large number of identifications.

In addition, some ethylenically unsaturated monomers have strong reactivity between the functional groups contained in them and the functional groups contained in acrylic polymers, and in such cases, gelation due to the reaction between the two may be difficult. From the viewpoint of prevention, the amount used must be set within an appropriate range.

Although the addition polymerization initiation reaction of this invention can be carried out using energy such as light or electron beams, it is usually carried out using a general radical polymerization catalyst that is used to form acrylic polymers that are sticky at room temperature. Bye.

This catalyst contains azo compounds such as azobisisobutyronitrile and various organic peroxides, and the use of organic peroxides has particularly good results in improving adhesion and cohesion. be done.

Examples of such organic peroxides include benzoyl peroxide, cumene hydroperoxide, and di-tert-
Examples include butyl peroxide, tert-butyl peroxybenzoate, lauroyl peroxide, ketone peroxide, tert-butyl peroxy 2-ethylhexanoate, methyl ethyl ketone peroxide, and cyclohexanone peroxide.

The amount of polymerization catalysts such as organic peroxides and azo compounds used is about 0.01 to 5 parts by weight, preferably about 0.05 to 3 parts by weight, based on 100 parts by weight of the ethylenically unsaturated monomer. be.

The temperature of the addition polymerization reaction greatly affects the molecular weight of the addition polymer obtained as well as the amount of polymerization catalyst used, so it is best to set it appropriately depending on the required molecular weight, but generally the temperature is about 50 to 90°C. You can do it with

Of course, it is also possible to carry out the addition polymerization reaction using a redox catalyst, and in this case it may be carried out at about room temperature.

The polymerization reaction product obtained in this way contains some homopolymers or copolymers of ethylenically unsaturated monomers as a polymer component, but is mainly an addition polymerized polymer added to an acrylic polymer that is sticky at room temperature. This includes:

The molecular weight of the adduct in this addition polymerization almost corresponds to the molecular weight of the homopolymer or copolymer, and can be varied depending on the selection of the conditions of the addition polymerization reaction.
Generally about 1000 to 100000, preferably 50
It is about 00 to 70,000.

The above molecular weight is G. P. C. It can be easily determined from the molecular weight distribution curve obtained by the method.

The polymerization reaction product containing such an addition polymerization polymer itself exhibits pressure-sensitive adhesive properties with excellent initial and post-oral adhesion or cohesion to polyvinyl chloride molded products, and can be used as is as an adhesive for polyvinyl chloride. It can be provided to

However, if it is desired to further improve the cohesive strength of this adhesive to further improve the deterioration of the adhesive properties after oral administration, it is possible to further add a general crosslinking agent to this adhesive.

Such crosslinking agents include, for example, ethyl etherified methylol melamine, butyl etherified methylol melamine, tolylene diincyanate, hexamethylene diisonanate, alkylphenols, zinc acetate, tin chloride, calcium oxide, benzoyl peroxide, diglycidyl bisphenol A. Examples include ether.

The amount of these compounds may be small, and is 0.0 parts by weight per 100 parts by weight of the acrylic polymer that is sticky at room temperature.
About 0.01-15 parts by weight is sufficient.

The pressure-sensitive adhesive composition of the present invention may further contain known compounding agents such as colorants, fillers, anti-aging agents, and tackifiers, if necessary.

The pressure-sensitive adhesive composition of the present invention thus obtained exhibits good adhesion and adhesion to polyvinyl chloride molded products containing a low-molecular plasticizer, and also exhibits good adhesive strength and adhesive strength after aging. It is an excellent product and can be used extremely effectively as a pressure-sensitive adhesive composition for vinyl chloride compared to conventional pressure-sensitive adhesives.

This invention will be described in more detail below with reference to Examples, but this invention is not limited to these and various modifications can be made without departing from the technical idea of this invention.

In the examples, parts mean parts by weight, and the adhesive strength and holding strength were measured by the following method.

<Adhesive strength> A pressure-sensitive adhesive composition was coated on both sides of a 25 μm polyester film so that one side had a thickness of 50 μm, and dried at 120°C for 3 minutes to make a double-sided adhesive tape. It was pasted on a polyvinyl chloride resin plate containing % by weight, left in an atmosphere of 50°C x 85% RH, and the adhesive strength (j'/20mm) was measured orally after 180° peeling according to JIS C-2107. did.

Holding power〉 A double-sided adhesive tape similar to the adhesive strength test was made, and it was pasted to two 25 x 25 mm polyvinyl chloride resin plates containing 50% by weight of dioctyl phthalate, and a load of 1 kg was applied at 40°C. It was left in an atmosphere of 50° x 85% R,H, and the time (minutes) until the Bakelite plate fell was measured.

Example 1 100 parts of a monomer mixture consisting of 70 parts of n-butyl acrylate, 30 parts of 2-ethylhexyl acrylate, and 3 parts of acrylic acid, 200 parts of toluene, and 0.1 part of benzoyl peroxide were charged into a three-necked flask. After stirring for 60 minutes while purging with nitrogen, the temperature was raised to 62°C and a polymerization reaction was carried out for 7 hours.

The obtained polymer solution contained an acrylic polymer having an average molecular weight of about 250,000 and was sticky at room temperature.

Next, after cooling this polymer solution to 50°C, a monomer mixture of 30 parts of styrene and 3 parts of acrylic acid was added to 100 parts of the above acrylic polymer (corresponding to the number of parts of the monomer mixture). Copolymer glass transition point 372°K)
Then, 1 part of benzoyl peroxide was added to 100 parts of the above monomer mixture, and after purging the system with nitrogen for 30 minutes, the temperature was raised to 75°C and an addition polymerization reaction was carried out for 4 hours. The resulting addition polymer has a molecular weight of G. P. It was 25,000 by C.

To the solution containing this addition polymerized polymer, 0.2 part of zinc acetate was further added as a crosslinking agent to obtain a pressure-sensitive adhesive composition for vinyl chloride of the present invention.

Example 2 As an unsaturated monomer for addition polymerization, a monomer mixture of 40 parts of methyl methacrylate and 4 parts of acrylic acid (a copolymer) was used instead of a monomer mixture of 30 parts of styrene and 3 parts of acrylic acid. A pressure-sensitive adhesive composition for vinyl chloride was prepared in exactly the same manner as in Example 1, except that a glass transition point (glass transition point: 376°K) was used.

Comparative Example 1 0.2 parts of zinc acetate as a crosslinking agent was directly added to the acrylic polymer solution obtained by the method of Example 1 to prepare a pressure-sensitive adhesive composition for vinyl chloride.

Comparative Example 2 The monomer mixture for addition polymerization described in Example 1 was
Acrylic acid n-7" Chiluac 1 is added to the polymerization system during the formation of the acrylic polymer solution described in
A polymer solution containing an acrylic polymer composed of 2-ethylhexyl lurate-styrene-acrylic acid and having an average molecular weight of approximately 220,000 was prepared, and 0.2 part of zinc acetate was added to this solution to form a pressure-sensitive adhesive composition for PVC. did.

Comparative Example 3 The monomer mixture for addition polymerization described in Example 2 was used in Example 1.
An acrylic polymer having an average molecular weight of about 300,000 and consisting of n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, and acrylic acid is added to the polymerization system during the formation of the acrylic polymer solution described in . 0.2 part of zinc acetate was added to this solution to prepare a pressure-sensitive adhesive composition for vinyl chloride.

Example 4: To a monomer mixture of 100 parts of methyl methacrylate and IO parts of acrylic acid, 150 parts of a mixed solvent of toluene:ethanol=8:2, 0.1 part of benzoyl peroxide, and the above monomers. A copolymer having an average molecular weight of 25,000 was prepared by adding 3 parts of lauryl mercaptan to 100 parts of the mixture and carrying out a copolymerization reaction, and this copolymer was added to the acrylic polymer solution obtained by the method of Example 1. 44 parts per 100 parts of acrylic polymer
0.2 parts of zinc acetate was added to prepare a pressure-sensitive adhesive composition for vinyl chloride.

Comparative Example 5 100 parts of a monomer mixture consisting of 70 parts of n-butyl acrylate, 30 parts of 2-ethylhexyl acrylate, and 3 parts of acrylic acid, 300 parts of toluene, and 0.1 part of benzoyl peroxide were charged into a three-necked flask. After stirring for 60 minutes while purging with nitrogen, the temperature was raised to 65° C. and reacted for 12 hours to form a polymer solution containing an acrylic polymer having an average molecular weight of about 80,000.

To this solution were added the monomer mixture for addition polymerization described in Example 2 and 1.5 parts of benzoyl peroxide per 100 parts of this mixture, and the temperature was raised to 80°C to carry out an addition polymerization reaction for 4 hours. Ta.

The addition polymer thus obtained had a molecular weight of 20,000.

Additionally, 0.0% zinc acetate was added to the solution containing the addition polymerized polymer.
2 parts were added to prepare a pressure sensitive adhesive composition for vinyl chloride.

The adhesive strength and retention strength of each of the above-mentioned Examples 1 to 2 and Comparative Examples 1 to 5 were examined at initial stage and after oral administration, and the results are as shown in Table 1 below. Ta.

Comparative Example 4 had very poor cohesiveness (because it was measured, 3.0 parts of tolylene diisocyanate was added in addition to 0.2 parts of zinc acetate as a crosslinking agent).

Example 3 100 parts of a monomer mixture consisting of 45 parts of n-butyl acrylate, 40 parts of 2-ethylhexyl acrylate, 10 parts of methyl methacrylate, and 5 parts of acrylic acid, 30 parts of benzene
0 part of benzoyl peroxide and 0.1 part of benzoyl peroxide were placed in a three-necked flask, and in the same manner as in Example 1, a polymer solution containing an acrylic polymer having an average molecular weight of about 350,000 and sticky at room temperature was prepared. Formed.

To this polymer solution, a monomer mixture consisting of 30 parts of styrene and 3 parts of acrylic acid per 100 parts of acrylic polymer and 1 part of benzoyl peroxide per monomer age were added, and the system was heated to 30 parts by weight. After heating with nitrogen for a minute,
The temperature was raised to 73°C and an addition polymerization reaction was carried out for 4 hours to obtain a pressure-sensitive adhesive composition for vinyl chloride of the present invention.

Comparative Example 6 100 parts of a monomer mixture consisting of 30 parts of n-butyl acrylate, 55 parts of decyl acrylate, 10 parts of methyl methacrylate, and 5 parts of acrylic acid, 300 parts of benzene, and 0.1 part of benzoyl peroxide were mixed into three parts. The mixture was poured into a neck flask and stirred for 60 minutes while purging with nitrogen, then heated to 65° C. and a polymerization reaction was carried out for 7 hours.

The obtained polymer solution contained an acrylic polymer having an average molecular weight of about 400,000 and being sticky at room temperature.

To this polymer solution, the same amount of the monomer mixture for addition polymerization described in Example 3 and benzoyl peroxide were added to 100 parts of the polymer, and after purging the system with nitrogen for 30 minutes, the temperature was raised to 83°C. An addition polymerization reaction was carried out for 4 hours to obtain a pressure-sensitive adhesive composition for vinyl chloride.

The initial and aged adhesive properties of the pressure-sensitive adhesive compositions for PVC of Example 3 and Comparative Example 6 were as shown in Table 2 below.

Example 4 100 parts of a monomer mixture consisting of 20 parts of ethyl acrylate, 80 parts of n-butyl acrylate, and 5 parts of acrylic acid,
200 parts of ethyl acetate and 0 parts of benzoyl peroxide
．． One part was put into a three-necked flask, and the same procedure as in Example 1 was carried out to form a polymer solution containing an acrylic polymer having an average molecular weight of about 300,000 and being sticky at room temperature.

To this polymer solution, 70 parts of vinyl acetate was added to 100 parts of polymer, and benzoyl peroxide Q was added to 100 parts of vinyl acetate. After adding 5 parts of the mixture and purging it with nitrogen for 30 minutes, the temperature was raised to 70°C and an addition polymerization reaction was carried out for 6 hours.
A pressure-sensitive adhesive composition for vinyl chloride according to the present invention was prepared.

Example 5 100 parts of 2-ethylhexyl acrylate and 5 parts of acrylic acid
100 parts of a monomer mixture consisting of A polymer solution was formed containing an acrylic polymer having the following properties.

To this polymer solution were added 30 parts of acrylonitrile per 100 parts of polymer and 1 part of benzoyl peroxide per 100 parts of this acrylonitrile, and after purging with nitrogen for 30 minutes, the temperature was raised to 80°C and an addition polymerization reaction was carried out for 4 hours. I did it.

0.05 part of tolylene diisocyanate was added to the solution containing the addition polymerization polymer obtained in this way to prepare a pressure-sensitive adhesive composition for vinyl chloride of the present invention. 3 Examples 6 90 parts of n-butyl acrylate, Methyl methacrylate 10
and 2 parts of 2-hydroxyethyl acrylate, 300 parts of benzene, and 0.1 part of benzoyl peroxide were charged into a three-necked flask, and the same procedure as in Example 1 was carried out until the average molecular weight was approximately A polymer solution containing an acrylic polymer having a tackiness at room temperature of 300,000 was formed.

To this polymer solution, 90 parts of a monomer mixture (glass transition point of the copolymer: 281°K) consisting of 60 parts of methyl methacrylate, 40 parts of n-butyl acrylate, and 5 parts of acrylic acid and 0 parts of benzoyl peroxide were added to 100 parts of the polymer. After adding .9 parts and replacing with nitrogen for 30 minutes,
The temperature was raised to 5° C. and an addition polymerization reaction was carried out for 6 hours to obtain a pressure-sensitive adhesive composition for vinyl chloride of the present invention.

Example 7 Using the polymer solution containing the acrylic polymer with an average molecular weight of approximately 250,000 obtained in Example 1, after volatilizing all the organic solvent (toluene) in this solution, it was placed in a flask equipped with a high viscosity stirrer. It was then replaced with nitrogen for 2 hours.

Next, 40 parts of methyl methacrylate was added to 100 parts of polymer, 10 parts of benzoyl peroxide and 0.2 parts of lauryl mercaptan were added to 100 parts of methyl methacrylate, and the temperature of the system was raised to 70°C. Addition polymerization reaction was carried out for 3 hours.

The addition polymer thus obtained had an adduct having a molecular weight of 8,000, and this polymer was used as it was as the pressure-sensitive adhesive composition for vinyl chloride of the present invention.

Comparative Example 7 To the acrylic polymer solution obtained in Example 5, 100 parts of ethyl acrylate (glass transition point of homopolymer 250°K) and 1 part of benzoyl peroxide were added to 100 parts of the polymer. Addition polymerization reaction was carried out in the same manner as above.

Thereafter, 1.0 part of tolylene diisocyanate was added to prepare a pressure-sensitive adhesive composition for vinyl chloride.

Comparative Example 8 To the acrylic polymer solution obtained in Example 5, 100 parts of a monomer mixture of 90 parts of ethyl acrylate and 10 parts of acrylic acid (glass transition point of the copolymer: 265°K) was added to 100 parts of the polymer. and 1 part of benzoyl peroxide were added, and an addition polymerization reaction was carried out in the same manner as in Example 5.

Then tolylene diisocyanate 0. 5 parts were added to prepare a pressure-sensitive adhesive composition for vinyl chloride.

The results of examining the initial and oral adhesion properties of each of the compositions of Examples 5 to 7 and Comparative Examples 7 to 8 are as follows:
It was as shown in the table.

Claims (1)

[Claims] 1. A pressure-sensitive adhesive composition for polyvinyl chloride that is applied to molded polyvinyl chloride products containing a low-molecular plasticizer, which comprises acrylic acid or methacrylic acid and an aliphatic monohydric alcohol having 8 or less carbon atoms. Main monomer consisting of an ester of 50 to 9 9.9
5% by weight, 0.05 to 20% by weight of an unsaturated monomer having one carbon-carbon double bond having a polar group such as a carboxyl group, hydroxyl group, or amide group, and copolymerized with these monomers. Using an acrylic polymer that is sticky at room temperature and has an average molecular weight of about 100,000 or more and is composed of 0 to 30% by weight of a vinyl monomer having one possible carbon-carbon double bond,
An addition polymer obtained by further addition polymerizing one or more ethylenically unsaturated monomers that can make the homopolymer or copolymer have a glass transition point of 273°K or higher in the presence of this acrylic polymer, A pressure-sensitive adhesive composition for vinyl chloride having excellent initial and post-oral adhesion properties, characterized in that it is contained as a polymer component in the composition. 2 The ethylenically unsaturated monomer for addition polymerization is styrene,
selected from at least one of the group of vinyl acetate, acrylonitrile and methacrylonitrile, and the group of acrylic esters, methacrylic esters and styrene derivatives whose homopolymer glass transition point can be 273°K or higher Claim 1 which is
A pressure-sensitive adhesive composition for vinyl chloride as described in 2. 3 The ethylenically unsaturated monomer for addition polymerization is styrene,
Selected from at least one of the group of vinyl acetate, acrylonitrile, and methacrylic nitrile, and the group of acrylic esters, methacrylic esters, and styrene derivatives whose homopolymers can have a glass transition temperature of 273°K or higher. unsaturated monomers, and those copolymerizable with this monomer and whose copolymers have a glass transition point of 27
The pressure-sensitive coating composition for vinyl chloride according to claim 1, which comprises another unsaturated monomer capable of having a temperature of 30K or higher. 4. The unsaturated monomer selected from the group of acrylic esters, methacrylic esters, and styrene derivatives is one whose homopolymer can exhibit a glass transition point of 3000 K or more. pressure-sensitive adhesive composition for PVC. 5. The pressure-sensitive adhesive composition for vinyl chloride according to claim 4, wherein the methacrylic acid ester is methyl methacrylate. 6. Pressure-sensitive welding for vinyl chloride according to any one of claims 1 to 5, in which 5 to 200 parts by weight of ethylenically unsaturated monomer for addition polymerization is used for 100 parts by weight of acrylic polymer. Orthodontic composition. 7. The polyvinyl chloride texture according to any one of claims 1 to 5, wherein 10 to 150 parts by weight of an ethylenically unsaturated monomer for addition polymerization is used per 100 parts by weight of the acrylic polymer. Pressure adhesive composition. 8. The pressure-sensitive adhesive composition for vinyl chloride according to any one of claims 1 to 7, which contains an organic solvent in the addition polymerization system. 9. Claim 8, wherein the content of the organic solvent is 5 to 900 parts by weight based on 100 parts by weight of the acrylic polymer.
Pressure-sensitive straightening composition for vinyl chloride as described in 2. 10. The pressure-sensitive adhesive composition for vinyl chloride according to any one of claims 1 to 7, which does not contain an organic solvent in the addition polymerization system. 11. A pressure-sensitive adhesive for vinyl chloride according to claim 10, which contains a chain transfer agent in the addition polymerization system in an amount of 0.01 to 1.0 parts by weight based on 100 parts by weight of the ethylenically unsaturated monomer. Composition. 12. The pressure-sensitive adhesive composition for vinyl chloride according to any one of claims 1 to 11, which uses an organic peroxide as an addition polymerization catalyst. 13 In a pressure-sensitive adhesive composition for polyvinyl chloride that is applied to polyvinyl chloride molded products containing a low-molecular plasticizer, the main unit is an ester of acrylic acid or methacrylic acid and an aliphatic monohydric alcohol having 8 or less carbon atoms. Quantity 50-9 9.
9 5% by weight, 0.05 to 20% by weight of an unsaturated monomer having one carbon-carbon double bond and a polar group such as a carboxyl group, hydroxyl group, or amide group, and co-monomers with these monomers. Consisting of 0 to 30% by weight of a vinyl monomer having one polymerizable carbon-carbon double bond, with an average molecular weight of approximately 10
An acrylic polymer having tackiness at room temperature of 10,000°K or more is used, and one or more ethylenic unsaturations that can cause the homopolymer or copolymer to have a glass transition point of 273°K or more in the presence of this acrylic polymer. An addition polymer obtained by addition polymerizing monomers,
A pressure-sensitive adhesive composition for vinyl chloride having excellent initial and post-oral adhesion properties, characterized in that it is contained as a polymer component in the above composition, and further a crosslinking agent is blended with this polymer component.