JPS63122708A - Production of radically curable copolymer resin - Google Patents

Abstract

PURPOSE:To obtain the titled resin free from such factors like ester linkage in the main chain as to deteriorated physical properties, by copolymerization between a styrene monomer and (meth)acrylic acid followed by reaction between glycidyl(meth)acrylate and the carboxyl group in the resulting resin composition. CONSTITUTION:A styrene monomer of formula CH2=C(R3)X [X is (alkyl or halogenated)phenyl; R3 is H or CH3] and (meth)acrylic acid are thermally copolymerized in a continuous manner at pref. 120-130 deg.C to make a resin composition. Thence, such an amount of glycidyl (meth)acrylate as to be virtually equimolar to the epoxy group in said composition is added to this composition to carry out a reaction between the epoxy group and the carboxyl group, thus obtaining the objective copolymer resin with its side chain carrying (meth) acryloyl group of formula (R1 and R2 are each H or CH3) this copolymer resin has the main chain with its polymerization degree not too high, being applicable to various uses.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing a radical-curable resin useful for various uses, which has a polymerizable acryloyl group or methacryloyl group at the end of a side chain.

[Prior Art] Typical radical curable resins are unsaturated polyester resins and vinyl ester resins, and diallyl phthalate resins are also used for applications such as molding materials and decorative laminates.

Each of these resins has its own characteristics.

It is used for a variety of purposes due to its physical properties, and has become indispensable.

On the other hand, however, with rapid advances in technology, resins with higher performance are often required, and resins often have to be improved in response to these demands.

For example, existing radical-curable resins such as unsaturated polyester resins have ester bonds in the constituent molecules of the main chain polymer or main chain oligomer, and this ester bond provides physical properties such as water resistance and chemical resistance. However, it has the disadvantage that it does not improve beyond a certain level.

On the other hand, in order to produce a resin that does not have an ester bond in the main chain, a method is generally known in which the main chain is formed by a polymerization reaction of a vinyl compound or the like. However, when this method is followed, a main chain with an excessively high degree of polymerization is usually obtained, making it difficult to obtain a curable resin that can be used for various purposes. In addition, when various polymerization regulators are used to lower the degree of polymerization in this method, they tend to have an adverse effect on the physical properties of Resin 1.

[Problems to be Solved by the Invention] The purpose of the present invention is to improve the above-mentioned drawbacks of existing resins and expand their uses, as well as to eliminate factors that impair physical properties such as ester bonds in the main chain. It is an object of the present invention to provide a method for producing a resin that does not contain any of the following:

[Means for Solving the Problems] The above objects of the present invention are achieved by the method for producing a radically curable copolymer resin according to the present invention.

That is, according to the present invention, the general formula 0% [wherein X is any one of a phenyl group, an alkylphenyl group, and a halogenated phenyl group, and R1, R2,
R3 is hydrogen or a methyl group, and m and n are positive integers, indicating that both monomers are randomly copolymerized in the main chain. , both of which are referred to as (meth)acryloyl groups, is a method for producing a radically curable copolymer resin in which a styrenic monomer represented by CH2=C(R3)X and (meth)acrylic acid are successively combined. A resin composition is produced by thermal polymerization, and then glycidyl (meth)acrylate is added in a substantially equimolar amount to the carboxyl group contained in the composition to react the carboxyl group with the epoxy group. A method for producing a copolymer resin is provided.

[Work] The method for producing the copolymer resin of the present invention consists of the following two steps.

a) Production of a copolymer resin composition having a carboxyl group in the side chain by copolymerization of a styrene monomer and (meth)acrylic acid b) Carboxyl groups and glycidyl contained in the above copolymer resin composition Reaction with (meth)acrylate In the present invention, the molar fraction of (meth)acrylic acid in the copolymer resin in the first step a) is 1 to 90%, preferably 5 to 50%. Although it depends on the application, if the molar fraction of (meth)acrylic acid in the copolymer resin is 1% or less, the radical polymerization rate described below will be slow and the physical properties after curing will be insufficient.

On the other hand, if it exceeds 90 mol %, the cured product will be too hard and rather brittle.

In the present invention, some of the styrene monomers as monomers constituting the main chain are methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, It is also possible to improve the physical properties by substitution with monomers such as lauryl methacrylate, acrylonitrile, vinyl acetate, vinylidene chloride, vinyl chloride, dibutyl maleate, dioctyl maleate, and vinyl propionate.

In the present invention, the reaction in the first step a) consists of organic peroxide,
Without using radical polymerization initiators such as azo compounds,
Copolymerize by heat.

That is, the reaction in the first step a) is carried out by continuously supplying a styrene monomer and (meth)acrylic acid to a reactor for thermal copolymerization, and by continuously removing the product from the reactor. The raw materials, styrenic monomer and (meth)acrylic acid, may be supplied to the reactor as a mixture in advance, or may be supplied separately.

The reaction in the first step a) can be carried out at a temperature of 120 to 300°C, but humidity lower than 120°C slows down the polymerization rate, and humidity higher than 300°C lowers the polymerization yield, which is not preferred.

The reaction in the first step a) may be carried out under reduced pressure, normal pressure, or increased pressure.

In the first step a) of the present invention, a copolymer having desired physical properties can be obtained by appropriately changing the mixing ratio of the monomers, reaction temperature, etc. Furthermore, if necessary, a polymerization regulator such as mercaptans may be used in combination without any problem.

Moreover, this invention method allows continuous thermal copolymerization,
It can be applied to any polymerization by adding a catalyst, and can also be applied to solution polymerization.

In the reaction of the second step (a) in the present invention, a polymerization inhibitor such as hydroquinone is used to prevent the polymerization of the styrene monomer remaining in the reaction of the first step (a) and the crosslinking reaction between the copolymer resins. It is preferable to use them together.

In the reaction of the second step (a) in the present invention, the amount of epoxy group to be added and reacted is 0.9 to 1.1 equivalent ml per 1 equivalent m of carboxyl group contained, preferably 0.95 to 1
．． 05 equivalent.

The radically curable copolymer resin of the present invention can be cured by copolymerizing with a monomer as a monomer solution, or can be crosslinked by polymerizing the unsaturated bonds of the polymer without using a monomer in combination. It is.

The above seven polymers include styrene, vinyltoluene, chlorostyrene, methyl acrylate, ethyl acrylate,
Butyl acrylate, 2-ethylhexyl acrylate,
Examples include methyl methacrylate, ethyl methacrylate, butyl methacrylate, lauryl methacrylate, benzyl methacrylate, dibutyl maleate, dioctyl maleate, vinyl acetate, vinyl propionate, etc.
A mixture of more than one species may be used.

Furthermore, the resin of the present invention can be used in combination with fillers, reinforcing agents, mold release agents, coloring agents, curing agents, accelerators, stabilizers, etc., as necessary, to be widely used in FRP, adhesives, paints, molding materials, etc. Can be used.

[Examples] Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these Examples unless it departs from the gist of the present invention.

Throughout this specification, all temperatures are in degrees Celsius, and parts and percentages are by weight unless otherwise specified.

Length 1111 [Production of styrene-methacrylic acid copolymer] Inner diameter 4mmΦ, length 1.5mm equipped with pressure regulator, pressure gauge, and safety valve
A mixture of styrene (76 mL 1%), methacrylic R (23% by weight), and n-dodecyl mercaptan (1% by weight) was fed into a stainless steel reactor at a rate of 2.0 g/min.
The reaction was carried out under the conditions of 200°C and 5 to 7 kQ/Cm2. As a result, the reaction rate of styrene was 57% and the reaction rate of methacrylic acid was 72%, and a colorless and transparent viscous copolymer composition was obtained.

[Production of resin having (meth)acryloyl group in side chain] (Put the above copolymer composition (200ml) into a separable flask (1000ml) equipped with a stirrer, thermometer, and reflux condenser.
1, styrene (200 g), glycidyl methacrylate (76.0), and hydroquinone (0.2 g) were charged and reacted at 100° C. for 5 hours. As a result, the reaction rate of glycidyl methacrylate was 93%, and the resulting resin solution was pale yellow and transparent, and had a viscosity of 9 voids at 25°C.

To 100 parts of the above resin solution, 1 part of "Vermec N" (trade name, peroxide catalyst manufactured by NOF Corporation) and 0.5 part of cobalt naphthenate (6% Co) were added, and a room temperature gelling test was conducted. However, the gelation time was 11 minutes, and the shortest curing time was 11 minutes.
．． 4 minutes, the maximum exothermic temperature was 156°C.

Further, the cured resin had the following physical properties and was excellent in transparency.

Tensile strength 7.0kg/mm2 Bending strength
13.8kg/mm2 Bending elastic modulus 323k
G/mm2 Heat distortion temperature 125°C Example 2 [Manufacture of styrene-acrylic acid copolymer] Pressure regulator,
4mm inner diameter, 1.5m length, equipped with pressure gauge and safety valve.
A mixture of styrene (80% by weight) and acrylic acid (20% by weight) was fed into a stainless steel reactor at a rate of 2.59/min, and the mixture was reacted at 200° C. and 5 to 7 kq/cm 2 . As a result, the reaction rate of styrene was 55%, the reaction rate of acrylic acid was 72%, and a colorless and transparent viscous copolymer composition was obtained.

[Production of resin having (meth)acryloyl group in side chain] <m>The above copolymer composition (200ml) was placed in a separable flask (1000ml) equipped with a stirrer, a thermometer, and a reflux condenser.
g), styrene (200G), glycidyl acrylate (71Q), and hydroquinone (0,470) were charged and reacted at 100°C for 5 hours. As a result, the reaction rate of glycidyl acrylate was 95%, and the resulting resin solution was pale yellow and transparent, and had a viscosity of 10 voices at 25°C.

To 100 parts of the above resin solution, 1 part of "Vermec N" (trade name, peroxide catalyst manufactured by NOF Corporation) and 0.5 part of cobalt naphthenate (6% Co) were added, and a room temperature gelling test was conducted. As a result, the gelation time was 12 minutes, and the shortest curing time was 12 minutes.
The maximum exothermic temperature was 150°C.

Furthermore, the cured resin had the following physical properties and was excellent in transparency.゛

Claims (1)

[Claims] General formula ▲ Numerical formula, chemical formula, table, etc. ▼ [In the formula, X is any one of a phenyl group, an alkylphenyl group, and a halogenated phenyl group,
2. R_3 is hydrogen or a methyl group, and m and n are positive integers, indicating that both monomers are randomly copolymerized in the main chain.] Acryloyl group or methacryloyl group at the end of the side chain A method for producing a radically curable copolymer resin having the following steps: continuous thermal polymerization of a styrenic monomer represented by CH_2=C(R_3) production of a copolymer resin, and then adding substantially equimolar glycidyl methacrylate or glycidyl acrylate to the carboxyl groups contained in the composition to react the carboxyl groups with the epoxy groups. Method.