JPH0349285B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for producing a radically curable resin having a novel structure useful for various uses such as paints, adhesives, molding materials, and FRP. [Conventional technology] Currently, unsaturated polyester resins and vinyl ester resins (epoxy acrylate resins) are typical as radical-curing resins that can be cured at room temperature, and they are used in a wide range of fields by taking advantage of their respective characteristics. ing. However, as the applications expand, the performance required of the resin becomes more detailed and sophisticated, and it may be difficult to satisfy these demands with conventional resins. For example, taking heat resistance as an example, as long as styrene is used as a crosslinking agent, its practical range in terms of heat distortion temperature is at most 120℃, and it is used for applications that require higher temperatures. I can't do that.
Although there are special highly reactive resins that are heat resistant and have a heat distortion temperature of 130 to 150℃, in many cases other physical properties such as mechanical strength are insufficient, making them problematic for practical use. This sometimes occurred. [Problems to be Solved by the Invention] In view of the above situation, the present inventors have conducted various studies in order to industrially easily produce a resin with high performance that exceeds the physical properties of these existing resins, particularly vinyl ester resins. The present invention was achieved by discovering a method for producing a radically curable resin having a novel structure with excellent heat resistance and mechanical strength. [Means for solving the problem] That is, the method for producing a curable resin of the present invention includes (A) adding monovalent phenols to an epoxy resin having two or more epoxy groups in one molecule; An epoxy resin-phenol adduct that shares two or more hydroxyl groups and allyloxymethylene groups in each molecule, which is obtained by reacting the group and the phenolic hydroxyl group in substantially equimolar amounts, and (B ) An epoxy resin having two or more epoxy groups in one molecule is reacted with acrylic acid or methacrylic acid (hereinafter referred to as (meth)acrylic acid) in a ratio that makes the epoxy groups and carboxyl groups substantially equivalent. 2 or more acryloyl groups or methacryloyl groups in each molecule (hereinafter referred to as (meth)acryloyl groups) obtained by
and a vinyl ester resin that shares a hydroxyl group with (C) a diisocyanate to form components (A) and (B) with component (C) through at least four urethane bonds. This is characterized by the fact that they are connected together. [Function] First, in order to aid understanding of the present invention, the chemical structural formula of the curable resin of the present invention will be shown using representative examples. Epoxy resin-phenol adduct (A) that shares two or more hydroxyl groups and allyloxymethylene groups in each molecule Vinyl ester resin (B) that shares two or more (meth)acryloyl groups and hydroxyl groups in each molecule

〔Example〕

Next, examples will be shown below to help understand the present invention. Example 1 Production of epoxy resin-phenol adduct [] 1 equipped with a stirrer, reflux condenser, and thermometer
In a three-necked flask, 360 g of Epicote 827 (produced by Yuka Ciel Epoxy Co., Ltd.) as an epoxy resin, 188 g of phenol, and 1.5 g of trimethylbenzylammonium chloride are charged and the temperature is raised. When the temperature exceeds 120°C, heat is generated rapidly. Cool and keep at 150-160℃, then reheat.
After reacting at 150-160°C for 5 hours, infrared analysis showed that free epoxy groups had completely disappeared. The epoxy resin-phenol adduct [] cooled to room temperature was syrup-like and pale yellowish brown in color. Production of isocyanate adduct [] Weighed 350 g of adduct [], 150 g of styrene, and 0.01 g of parabenzoquinone into a similar device, and
After heating and dissolving at ~70°C, 220 g of 2,4-tolylene diisocyanate was added and reacted at 60°C for 5 hours. As a result of analysis by di-n-butylamine-hydrochloric acid titration method, the isocyanate group concentration ranged from 3.8%. It was observed that the rate had decreased by almost half to 1.6%. 130 g of styrene was added to obtain an isocyanate adduct [] in the form of a pale yellowish brown liquid. Production of vinyl ester resin [ ] 1 with a stirrer, reflux condenser, and thermometer
In a three-necked flask, 360 g of the above-mentioned Epicote 827 as an epoxy resin, 172 g of methacrylic acid, 0.2 g of hydroquinone, and 1.5 g of trimethylbenzylammonium chloride were charged and reacted for 3 hours with vigorous stirring at 120 to 130°C, the acid value was
It became 5.9. 230 g of styrene was added, and vinyl ester resin [] was obtained in the form of a reddish brown liquid. Production of curable resin [A] 2 equipped with a stirrer, reflux condenser, and thermometer
Isocyanate adduct in a three-necked flask []
When the temperature reached 60℃, 2g of dibutyltin dilaurate was added and reacted at 60℃ for 3 hours. As a result of infrared analysis, free isocyanate groups completely disappeared. Was. Resin that can be cured by adding 410g of styrene [A]
was obtained with a reddish brown color and a viscosity of 9.7 poise. A system consisting of 100 parts of resin [A], 1.5 parts of #328E from Kayaku Nouri Co., Ltd. as a curing agent, and 0.5 part of cobalt naphthenate was gelled in 29 minutes and rapidly generated heat to give a cured resin. Its properties were: bending strength: 16.7 Kg/mm ² bending modulus: 460 Kg/mm ² Sharpie impact value: 3.7 Kg cm/cm ² heat distortion temperature: 127°C Rockwell hardness: M-113. Comparative Example 1 In the same device, 760 g of vinyl ester []
When 174 g of 2,4-tolylene diisocyanate (containing equimolar isocyanate groups as the isocyanate adduct []) was added and 1.6 g of dibutyltin dilaurate was added at 60°C, it gelled after about 3 minutes and was ready for practical use. No viable resin was obtained. Example 2 Production of epoxy resin-xylenol adduct [] 2 equipped with a stirrer, reflux condenser, and thermometer
In a three-necked flask, 360 g of DEN-431, 270 g of 2,6-xylenol, and 2 g of benzylmethylamine were charged as a novolak type epoxy resin.
After reacting at 150-160°C for 3 hours, infrared analysis confirmed that free epoxy groups had disappeared. Furthermore, 370 g of styrene and 0.1 g of hydroquinone were added to obtain an epoxy resin-xylenol adduct in the form of a pale reddish brown liquid. Production of isocyanate adduct [] To the entire amount of adduct [] cooled to around room temperature, 500 g of dipnylmethane diisocyanate and 330 g of styrene were further added, and the mixture was heated and reacted at 60°C for 5 hours, resulting in Example 1. Similar analysis revealed that the isocyanate value was reduced by almost half. The isocyanate adduct [ ] was obtained in a pale reddish brown liquid state. Production of curable resin [B] 3 equipped with a stirrer, reflux condenser, and thermometer
In a three-necked flask, 920 g of isocyanate adduct [], 760 g of vinyl ester [] used in Example 1, and 0.1 g of parabenzoquinone were charged.
1g of dibutyltin dilaurate after heating to 60℃
In addition, upon heating at 60°C for 3 hours, infrared analysis confirmed that free isocyanate groups had completely disappeared. By adding 520 g of styrene, a curable resin [B] having a reddish brown color and a viscosity of 22.6 poise was obtained. A resin prepared by adding 1.5 parts of #328E and 0.3 parts of cobalt naphthenate to 100 parts of resin [B] rapidly generated heat after gelling in 14 minutes, and the maximum exothermic temperature reached 154°C. The heat distortion temperature of the cured resin is 129℃, and the bending strength is
It was 14.9Kg/ ^mm2 . Example 3 Production of epoxy resin-α-naphthol adduct [] 2 equipped with a stirrer, reflux condenser, and thermometer
In a three-necked flask, add 260 g of Union Carbide's ERL-4221 as an epoxy resin, α-
Naphthol 280g, triphenylphosphine 2g
was charged, heated to 150 to 160°C, cooled if necessary, and reacted at 160°C for 8 hours. As a result of infrared analysis, it was confirmed that free epoxy groups had disappeared. Next, p-methylstyrene 460 at a temperature of around 120℃
g was added, and an epoxy resin-α naphthol adduct [] was obtained in the form of a light reddish brown liquid. Production of isocyanate adduct [] To the total amount of epoxy resin-α naphthol adduct [], 440 g of isophorone diisocyanate,
Add 260g of p-methylstyrene and heat to 60°C, then add 3g of dibutyltin dilaurate and heat to 60°C.
After reacting at .degree. C. for 6 hours, the number of free isocyanate groups was found to have been reduced by approximately half using the same analytical method as in Example 1. The isocyanate adduct [ ] was obtained in a reddish brown liquid form. Production of vinyl ester resin [ ] 2 equipped with a stirrer, reflux condenser, and thermometer
As epoxy resin in a three-necked flask,
520g of ERL-4221, 344g of methacrylic acid,
Hydroquinone 0.5g, triphenylphosphine
After charging 2.5 g and reacting at 120 to 125° C. for 5 hours, the acid value became 7.4, so 740 g of p-methylstyrene was added to obtain vinyl ester resin [ ] in the form of a reddish-brown liquid. Production of curable resin [C] 700 g of vinyl ester resin [], 850 g of isocyanate adduct [], parabenzoquinone
Add 0.15g, dibutyltin dilaurate 2g,
After reacting at 60°C for 8 hours, infrared analysis confirmed that free isocyanate groups had disappeared. The obtained curable resin [C] has a reddish brown color and a viscosity of
It was 39 poise. A system in which 100 parts of resin [C], 1.5 parts of #328E, and 0.2 parts of cobalt naphthenate were added rapidly generated heat after gelling at room temperature in 24 minutes, and the maximum exothermic temperature reached 149°C. The molded product had a heat distortion temperature of 167°C, a bending strength of 11.9 kg/mm ^{, and} a Rockwell hardness of M-115. [Effects of the Invention] The curable resin having the novel structure of the present invention has the following properties:
It is easy to synthesize, and by radical curing, a cured product with physical properties superior to vinyl ester resins, especially heat resistance and mechanical strength, can be obtained. It is extremely useful for various uses such as wood and FRP.

Claims (1)

[Claims] 1 (A) An epoxy resin having two or more epoxy groups in one molecule is reacted with a monovalent phenol so that the epoxy groups and phenolic hydroxyl groups are substantially equimolar. (B) an epoxy resin-phenol adduct that shares two or more hydroxyl groups and allyloxymethylene groups in each molecule, obtained by Vinyl that shares two or more acryloyl groups or methacryloyl groups and hydroxyl groups in each molecule, obtained by reacting acrylic acid or methacrylic acid in a ratio in which epoxy groups and carboxyl groups are substantially equivalent. ester resin and (C) a diisocyanate to bond components (A) and (B) with component (C) through at least four urethane bonds. Method of manufacturing curable resin.