JPH01174514A - Thermosetting resin composition - Google Patents

Abstract

PURPOSE:To obtain the present composition, consisting of a reaction product of a copolymer having a specific composition with an unsaturated carboxylic acid, copolymerizable monomer and tetra- or polyfunctional crosslinking monomer and having hardly any deterioration in characteristics by moisture absorption due to excellent moisture resistance and improved curability. CONSTITUTION:A thermosetting resin composition obtained by initially copolymerizing 0-50mol.% alkyl (meth)acrylate (e.g., methyl acrylate), 10-50mol.% (meth)acrylic acid and 0-90mol.% other ethylenically unsaturated monomers (e.g., styrene) so as to provide 100mol.% total amount thereof and blending (A) 100pts.wt. reaction product of the resultant copolymer with an unsaturated carboxylic acid (anhydride) with (B) >=25pts.wt. monomer copolymerizable with the component (A) and (C) a tetra- or polyfunctional crosslinking monomer (e.g., divinylbenzene) in an amount of >=0.5pt.wt. based on 100pts.wt. total amount of the components (A) and (B). Furthermore, maleic acid, etc., are cited as the above-mentioned carboxylic acid (anhydride).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thermosetting resin composition that has excellent curability and good properties (particularly dielectric properties) of the cured product.

(Prior art) Generally, phenolic resin has electrical properties, 9 mechanical properties,
Balanced properties such as heat resistance and chemical resistance, and
Because it is inexpensive, it is widely used in electrical and electronic fields, mainly for consumer use.

(Problems to be Solved by the Invention) Phenol resins have a disadvantage in that they require a long time for curing because their curing reaction is polycondensation-based or ionic polymerization-based. An example of such a resin having excellent curability is unsaturated polyester resin. The curing reaction of this unsaturated polyester resin is radical polymerization, so it can be cured at room temperature if a catalyst system is selected, but since the resin skeleton contains many polar groups (carbonyl groups), the cured product does not absorb moisture. It becomes easier. For this reason, a drawback of unsaturated polyester resins is a decrease in various properties after moisture absorption.

The present invention solves these problems.

(Means for Solving the Problems) The present invention provides for the use of alkyl acrylates or alkyl methacrylates in a range of 0 to 50 moles, and hydroxyalkyl acrylates or hydroxyalkyl methacrylates in a range of 10 to 50 moles.
A copolymer obtained by copolymerizing these in the range of ~50 mol and other ethylenically unsaturated monomers in the range of 0 to 90 mol for a total amount of 100 mol, and unsaturated carboxyl. Reactant with acid or its anhydride (A) 1
00 parts by weight, monomer (B) 2 copolymerizable with this reactant
The present invention relates to a thermosetting resin composition containing 5 parts by weight or more and 0.5 parts by weight or more of a tetrafunctional or higher crosslinking monomer per 100 parts by weight of (A) and (8).

The alkyl acrylate or alkyl methacrylate used in the present invention is, for example, methyl acrylate.

Acrylic acid alkyl esters such as butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate,
Examples include alkyl methacrylates such as butyl methacrylate and 2-ethylhexyl methacrylate. Examples of hydroxyalkyl acrylate or hydroxyalkyl methacrylate include hydroxyalkyl acrylate esters such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 4-hydroxybutyl acrylate, and 2-hydroxyalkyl acrylate. Examples include hydroxyalkyl methacrylates such as hydroxyethyl, 2-hydroxypropyl methacrylate, and 4-hydroxybutyl methacrylate. Examples of other ethylenically unsaturated monomers include styrene, styrene derivatives such as α-methylstyrene, organic nitriles such as acrylonitrile and methacrylonitrile, vinyl esters of organic acids such as vinyl acetate and vinyl propionate, and acrylic Acids, methacrylic acid, acrylic esters, methacrylic esters, dicyclopentadiene acrylates, compounds having an acid amide group or acid halide group derived from these compounds, N-acrylate derivatives of N-methylolacrylamide acid , N-methacrylate derivatives such as N-methylolmethacrylamide, and the like. As an unsaturated carboxylic acid.

N, t#f, fumaric acid, maleic acid, itaconic acid, etc., and anhydrides thereof include maleic anhydride, itaconic anhydride, etc. Examples of copolymerizable monomers include the above-mentioned alkyl acrylates.

Alkyl methacrylate, hydroxyalkyl acrylate, hydroxyalkyl methacrylate.

Other ethylenically unsaturated monomers may be used.

Copolymer of alkyl acrylate or alkyl methacrylate, hydroxyalkyl acrylate or hydroxyalkyl methacrylate, and ethylenically unsaturated monomer is 9
Although it can be produced by ordinary suspension polymerization, bulk polymerization, solution polymerization, etc., it requires a subsequent reaction with an unsaturated carboxylic acid or its anhydride and a crosslinking monomer of tetrafunctionality or higher.
It is preferable to manufacture using a bulk polymerization method or a solution polymerization method. The polymerization initiator used in the polymerization of this copolymer is an azo initiator such as azobisisobutyronitrile and azobiscyclohexanecarbonitrile, which are used in general radical polymerization.

tert-butyl hydroperoxide, di-tert-
Examples include peroxides such as butyl peroxide.

There are no particular restrictions. Examples of the polymerization inhibitor include hydroquinone, p-benzoquinone, etc., which are used in general radical polymerization, and are not particularly limited. Also.

In some cases, a chain transfer agent of alkyl mercaptans such as dodecyl mercaptan can be used to adjust the molecular weight of the copolymer. The esterification reaction between the hydroxyl group of this copolymer and the unsaturated carboxylic acid or its anhydride is carried out by a known method, and # is not limited.

The composition ratio of the resin composition of the present invention can be varied depending on the purpose of use and environment of use, but the preferable range is that the alkyl acrylate or alkyl methacrylate is used for coloring the resin liquid, for coloring the resin cured product, etc. The amount is determined to be in the range of 0 to 50 mol from the viewpoint of electrical properties. It also shows a decrease in properties (particularly dielectric properties).

The content of acrylic acid and hydroxyalkyl methacrylate is set in the range of 10 to 507% from the viewpoint of reactivity and workability of the copolymer.

If it is less than 10 moles, the reactivity of the copolymer will be significantly reduced, resulting in a long time for curing or a decrease in the properties of the cured product, and if it is more than 50 moles, the molecular weight of the copolymer will increase. Since it becomes a viscous liquid, it shows a decrease in workability and a decrease in various properties of the cured product.

The amount of ethylenically unsaturated monomer is set in the range of 0 to 90 mol from the viewpoint of clouding of the resin liquid and transparency of the cured resin. If it exceeds 90 mol, the solubility of the copolymer decreases, resulting in clouding of the resin liquid. becomes noticeable.

Transparency of the cured product is also lost.

The amount of the copolymerizable monomer is 25 parts by weight or more based on 100 parts by weight of the reaction product of the copolymer and the unsaturated carboxylic acid or its anhydride, from the viewpoint of the reactivity and workability of the resin liquid. If the amount is less than 100%, the reactivity of the resin liquid will be significantly reduced, resulting in a long time for curing and deterioration of various properties of the cured product, and the resin liquid will become viscous, resulting in a decrease in workability. . The amount of this monomer is usually 400 parts by weight or less. Examples of the tetrafunctional or higher crosslinking monomer include vinyl monomers such as divinylbenzene and divinyltoluene, and L3-butylene glycol diacrylate.

Polyfunctional acrylates such as diethylene glycol diacrylate, trimethylolpropane triacrylate, bisphenol A diacrylate, tris (acryloyloxyethyl) isocyanurate, 1,3-butylene glycol dimethacrylate, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, Examples include polyfunctional methacrylates such as bisphenol A dimethacrylate and tris(methacryloyloxyethyl)isocyanurate, and polyfunctional allyl compounds such as diallyl phthalate, triallyl cyanurate, and triallyl in cyanurate.

From the viewpoint of curability of the cured resin product, the amount of crosslinking monomer of tetrafunctionality or higher is 0 per 100 parts by weight of the above (A) and (B).
．． The amount is 5 parts by weight or more. If the amount is less than 0.5 part by weight, the cured resin product will not be sufficiently cured, and the properties expected in the first place will not be obtained. Further, even if the amount is more than 10 parts by weight, there is almost no change in the curability of the cured resin, and it is preferable to use 10 parts by weight or less.

The resin composition of the present invention has a relatively low viscosity and can be cured in a short time, so it is suitable for industrial materials (electrical insulation).

It can be used as a casting resin for civil engineering, construction, sports, leisure, etc. Also a removable agent.

Stabilizers, curing agents (catalysts), thickeners, fillers, crosslinking agents,
Reinforcing material (reinforcing material) 9 By adding colorants, lubricants, etc., it can be used as a molding material, paint, adhesive, and various other uses.

(Example) The present invention will be explained with reference to an example. Parts are by weight.

Example 1 Stirring device, heating device, cooling pipe, nitrogen gas inlet.

Installing the monomer inlet is 93I! 556 parts of methyl isobutyl ketone (hereinafter abbreviated as MIBK) was placed in a flask, and the temperature was raised to 100° C. while thoroughly purging with nitrogen. On the other hand, 2I! Styrene 35 & 3 parts (30 mol), butyl acrylate 587.6 parts (40 mol), 2-hydroxyethyl methacrylate 447.9 parts (30 mol), azobisisobutyronitrile 41.86 parts A mixed solution containing 6.96 parts of ditertiary-butyl peroxide and thoroughly stirred was added dropwise into the heated MIBK so that the entire amount disappeared in 3 hours. After dropping the entire amount, the reaction was continued for 3 hours, and 0.27 parts of hydroquinone was added and mixed.
A copolymer diagram was obtained. Furthermore, 225 parts of maleic anhydride was added at 100°C, and after 4 hours of reaction, the polymerization rate of 9 was 981.
After confirming that it was the same, it was cooled.

Next, a condenser was attached to the flask, and the pressure was gradually reduced to about 50 mmHg'J using an aspirator.
After heating to 100°C and removing MIBK, styrene 1 in which 0.02 part of hydroquinone was dissolved in advance.
61,118 parts of the copolymer was added, and stirring was continued until the copolymer was completely dissolved. After confirming that there was no insoluble matter, the mixture was cooled to obtain a resin composition (B). The heating residue (NV) of this resin composition (B) was about 52.

Divinylbenzene was added in an amount of 20 parts or less as shown in Table 1 to 100 parts of this resin composition (B).

In addition, Parhexa 3M (Pero-medium ciketals).

After adding 1 part of Nippon Oil & Fats Co., Ltd. product name) and thoroughly stirring and mixing, the high temperature curing properties (produced by JIS K6901)
Measurement temperature: 130°C In Table 1, Tg is gelation time, Tc
is the minimum curing time and Trnax is the maximum exothermic temperature)
was measured. Furthermore, heating was continued as it was, and after 30 minutes, the resin was rapidly cooled to obtain a cured resin product.

Finely crush this cured resin and take about 3 g.

After accurately weighing in a cylindrical filter AK with a diameter of 28 mm and a length of 100 mm, which had been previously dried to a constant weight, the mixture was extracted under reflux for 4 hours using a Soxhlet extraction apparatus using acetone (ioog) as a solvent. After extraction.

The thimble was dried in a vacuum dryer at 60°C for 4 hours.

The acetone extraction rate was calculated from the weight change before and after that.

Further, using the filtrate as it was, quantitative analysis of unreacted styrene monomer was performed using a gas chromatography device (manufactured by Hitachi, model 164), and the amount of residual styrene was calculated from the results. The results are summarized in Table 1.

Example 2 To the resin composition (81,100 parts) prepared in Example 1, 20 parts or less of ethylene glycol dimethacrylate was added as shown in Table 2, and Perhexa 3M (peroxyketals 1 NOF Co., Ltd.) was added. After adding 1 part of the company's product name) and thoroughly stirring and mixing.

In the same manner as in Example 1, high temperature curing properties (130'C), acetone extraction rate, and residual styrene amount were determined. The results are summarized in Table 2K.

Example 3 1c of triallylisocyanurate as shown in Table 3 was added to 100 parts of the resin composition (B) prepared in Example 1.
After adding 20 parts or less and further adding 1 part of Perhexa 3M (Peroxyketals 9, trade name manufactured by NOF Corporation) and stirring and mixing thoroughly, the high temperature curing properties (130" C), the acetone extraction rate and the amount of residual styrene were investigated.The results are shown in Table 3Kt.

Comparative Example 100 parts of the resin composition (B) prepared in Example 1 was mixed with Perhexa 3M (peroxyketals 9, a product manufactured by NOF Corporation) without the addition of divinylbenzene, ethylene glycol dimethacrylate, and triallyl isocyanurate. After adding and thoroughly stirring and mixing, high temperature curing characteristics (130° C.), acetone extraction rate, and residual styrene amount were examined in the same manner as in Example 1. Tables 1 to 3 show the results.
It was shown to.

Table 2 Table 3 As seen in Tables 1 to 3, the resin composition obtained in this example exhibits excellent curing properties. especially.

When divinylbenzene is used, the minimum curing time (T
c) is 5 to 20 seconds faster than the additive-free system, and curing is possible in a shorter time. Furthermore, both the acetone extraction rate and the amount of residual styrene, which are measures of the degree of hardening, decrease rapidly with the amount of the crosslinking monomer of tetrafunctionality or higher. Among them, when using divinylbenzene, the value is the smallest at the same amount added.

It is shown that the curability is further improved.

(Effects of the Invention) The resin composition of the present invention has no polar group in the main chain skeleton, so it has excellent moisture resistance and less deterioration of properties after absorbing moisture. Furthermore, since a crosslinking monomer of tetrafunctionality or higher is added when the resin is cured, it is possible to cure the resin more strongly in a shorter time and to obtain large molded products.

Agent: Patent attorney Kunihiko Wakabayashi.

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Claims (1)

[Claims] 1. Alkyl acrylate or alkyl methacrylate in a range of 0 to 50 mol%, hydroxyalkyl acrylate or hydroxyalkyl methacrylate in a range of 10 to 50 mol%, and other ethylenically unsaturated monomers in a range of 0
100 parts by weight of a reaction product (A) of a copolymer obtained by copolymerizing these with an unsaturated carboxylic acid or its anhydride in an amount such that the total amount is 100 mol% in the range of 90 mol%, A thermoplastic containing 25 parts by weight or more of a monomer (B) copolymerizable with the reactant and 0.5 parts by weight or more of a tetrafunctional or higher crosslinking monomer per 100 parts by weight of (A) and (B). Curable resin composition.