JPS5853644B2 - Photocurable heat-resistant resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-resistant unsaturated polyester resin composition that is cured by light irradiation.

More details: oxazolidone ring, isocyanurate i
, relates to a resin composition in which a sensitizer and, if necessary, a polymerizable monomer are added to a polymer having an ester bond and a polymerizable unsaturated group.

As a photocurable resin composition that can be easily cured by irradiation with light in the range of visible light to ultraviolet light, it is a polymer made by reacting an unsaturated basic acid with a polyhydric alcohol, a sensitizer and, if necessary, a polymerizable resin composition. Unsaturated polyester resin compositions to which monomers have been added are already known.

However, the cured film formed by irradiating this unsaturated polyester resin composition with light was not satisfactory in chemical resistance, solvent resistance, strength, heat resistance, etc.

Furthermore, in order to improve these drawbacks, epoxy-modified unsaturated polyester resin compositions are already known, which are made by adding a sensitizer and, if necessary, a polymerizable monomer to a polymer obtained by reacting an epoxy compound with an unsaturated basic acid. However, the cured film obtained by irradiating this resin composition with light has chemical resistance,
Although it has excellent solvent resistance and strength, it has the problem of unsatisfactory heat resistance, particularly heat softening temperature (Tg), high temperature strength, etc., and improvements are desired.

As a result of intensive research aimed at obtaining a photocurable resin composition that improves these drawbacks, the present inventor has developed an oxazolidone ring and isocyanurate i obtained by reacting an epoxy resin and an isocyanate compound in the presence of a heteroterminal-forming catalyst. A resin composition characterized by blending a photosensitizer and, if necessary, a polymerizable monomer with a polymer obtained by esterifying an unsaturated basic acid with a product having a molecular terminal epoxy group, is easily described. The present inventors have discovered a new fact that the object of the present invention can be achieved, and have completed the present invention.

Therefore, the present invention is easily cured by irradiation with light in the range of visible light to ultraviolet light, and the cured film has chemical resistance, solvent resistance, and heat resistance, and is suitable for use in paints, printing, etc. It is an object of the present invention to provide a photocurable resin composition useful for materials, reinforced plastics, and especially electrical insulation materials that require heat resistance.

The photocurable unsaturated polyester resin composition according to the present invention can be obtained as follows.

An unsaturated-basic acid is added to a molecular terminal epoxy resin having an oxazolidone ring and an isocyanurate ring obtained by reacting 1 to 5 equivalents of an epoxy compound with 1 equivalent of an isocyanate compound under a heterocycle-forming catalyst. −
An esterification reaction catalyst in which a part or most of the basic acid is replaced with one or more selected from unsaturated polybasic acids and anhydrous unsaturated polybasic acids, and if necessary a polymerization inhibitor. , a heating reaction is carried out in the presence of a solvent or monomer, and then a solvent or monomer is added as necessary to synthesize the compound.

A photocurable unsaturated polyester resin composition is obtained by adding a photosensitizer that induces a photocuring reaction to the resin composition synthesized here.

When synthesizing these, the reaction ratio between the epoxy group of the molecular terminal epoxy resin having an oxazolidone ring and an isocyanurate ring and the acid is 1 mole (equivalent) of the epoxy group per 1 mole of the total carboxyl groups of the acid. This is the amount.

The amount of other polymerization inhibitors, solvents, or polymerizable monomers used can be changed depending on the required curability, workability, performance, etc.

Incyanate compounds that can be used in the present invention include those generally used for producing polyurethane, such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, methylene bis(phenylisocyanate), ), dianisidine diisocyanate, toluidine diisocyanate, hexamethylene diisocyanate, ■, 4-diethylbenzene β-β
Examples include l-diisocyanate.

Epoxy resins that can be used in the present invention include bisphenol diglycidyl ether type, which is a reaction product of epichlorohydrin or β-methylepichlorobidrin and dihydric phenols, as well as glycidyl ester type and alicyclic epoxy. be.

The above dihydric phenols include 2,2'-bis(4-hydroxyphenyl)furopane, 4,4'-dihydroxyphenylmethane, 1,1bis(4hydroxyphenyl)ethane, and 2,2'-bis(4-hydroxyphenyl)ethane. (4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 4°4'-dihydroxydiphenyl, resorcinol, and the like.

The reaction ratio of the epoxy resin and incyanate compound is usually 1 to 5 equivalents of epoxy to 1 equivalent of incyanate, but preferably 2 to 3 equivalents of epoxy in consideration of the flexibility and softening temperature of the resulting resin.

Any heterocycle-forming catalyst can be used.

For example, lithium compounds such as aluminum chloride, iron chloride, lithium chloride, quaternary ammonium halides such as tetraethylammonium bromide, tetramethylammonium iodide, tetraethylammonium iodide, groups 2 A and 3 of the periodic table. Mention may be made of alkoxides and phenoxides of metal compounds of group B, aluminum phenoxide, calcium ethoxide, magnesium ethoxide, etc., and mixtures thereof.

The amount of these catalysts used is preferably 0.5 to 1% by weight based on the resin content.

In addition, quaternary ammonium halide is a catalyst for the formation of oxazolidone and isocyanurate rings as well as an ester bond, so it can be used as an unsaturated basic acid having a polymerizable or copolymerizable unsaturated bond that can be preferably used in the present invention. Generally, acrylic acid, meccrylic acid, sorbic acid, and cinnamic acid are sufficient for the purpose of the present invention.

In addition, monoesters of unsaturated polybasic acids can also be used.

For example, monoethyl ester of maleic acid.

A combination of monoesters of the above-mentioned unsaturated basic acids and unsaturated polybasic acids can also be used.

Further, unsaturated polybasic acids and anhydrous unsaturated polybasic acids that can be used in the present invention include maleic acid, maleic anhydride, fumaric acid,
Itaconic acid and the like can be mentioned, and one or more selected from these can also be used.

Esterification reaction catalysts that can be used in the present invention include, in addition to the above-mentioned quaternary ammonium halides and lithium compounds, primary, secondary, and tertiary amines, and their inorganic acids and organic acid salts.

The amount of these catalysts used is preferably 0.01 to 2 weight φ based on the resin content.

Furthermore, in the present invention, in order to prevent gelation during the reaction, phenols, quinones, and other compounds having a polymerization-inhibiting effect can be used as polymerization inhibitors, if necessary, and can also be added after the reaction.

Examples of these polymerization inhibitors include hydroquinone, vitroquinone monomethyl ether, benzoquinone phenothiazine, thiosemicarbasite, acetone thiocarbazone, and copper salts.As the solvent used in the present invention, examples include xylene toluene and dioxane. , cresol, dimethylformamide, cyclohexanone, methyl ethyl ketone, dipropyl ketone, cicarbitol,
One or more selected from cellosolve acetate and the like can also be used in combination.

Examples of polymerizable monomers that can be used in the present invention include acrylic esters, styrene methacrylates, divinylbenzene, vinyltoluene, acrylonitrile, methacrylonitrile, cyclopentadiene, vinylpyridine, diallyl tucrate/diallylisophthalate,
Triallylisocyanurate, vinyl acetate, vinylpyrrolidone, etc. can be used, and when used, one or more selected from these can also be used in combination.

Further photosensitizers that can be used in the present invention include carbonyl compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzylidene acetone, benzoylacetone, and benzophenone.

Nitrogen derivatives such as penzanthrone, benzaldehyde, pentyl, fuenathraquinone, ascorbic acid, etc.
For example, diazomethane, azobisisobutyronitrile,
Azobiscyclohexanecarbonitrile, hydrazine,
Phenylhydrazine, hydrabenzene, phenylhydrazine hydrochloride, triethanolamine, etc. Also, sulfur derivatives such as sodium benzenesulfonate, 5-salicylsulfonic acid, paraacetamidobenzenesulfonic acid, sodium p-toluenesulfonate, Diphenyl disulfide, etc., halogens and their derivatives, such as α-chloromethylnaphthalene, phenacyl halide, etc., inorganic complex salts, such as cobalt oxalate complexes, uranyl salts, such as uranyl nitrate, and pigments. phosphorus derivatives, such as triphenylphosphine, and Ziegler series. Catalysts, dithiocarbamates, xanthates, and equivalent substances of the compounds mentioned above, and one or more selected from these can also be used.

The total amount of photosensitizer used can be 0.01 weight φ or more based on the unsaturated polyester resin, but 0.1 to 5
Weight control is good.

The photocurable resin composition obtained here is cured by light irradiation, but organic metal salts, peroxides, and the like may be added to further promote curing.

As described above, the photocurable unsaturated polyester resin composition according to the present invention is composed of an unsaturated polyester resin composition having an oxazolidone ring, an isocyanurate ring, and an epoxy skeleton, and a photosensitizer, and is capable of irradiating visible light to ultraviolet light. When irradiated with a range of light (such as sunlight, a xenon lamp, or a low- to high-pressure mercury lamp as a light source), a photocuring reaction is induced by the photosensitizer, resulting in polymerization between unsaturated groups in the photocurable resin composition. The cured film that has undergone the reaction and is cured has excellent chemical resistance, solvent resistance, and heat resistance.

The photocurable unsaturated polyester resin composition of the present invention is easily cured by light irradiation, and the cured film has excellent chemical resistance, solvent resistance, heat resistance, especially high temperature strength, and excellent softening temperature. It is useful not only for paints, printing materials, and reinforced plastics, but also for electrically insulating materials that require heat resistance.

Examples are shown below to help understand the present invention, but the present invention is not limited thereto.

Example 1 Epoxy resin (trade name: Epon 828 manufactured by Shell Co., Ltd.
) 381 and 125 g of diphenylmethane diisocyanate.
, tetraethylammonium iodide 0. ! Add 125 g of dimethylformamide and raise the temperature to 135° C. while blowing nitrogen gas, and react for 2 hours.

The IR absorption spectrum of this reaction product is 2250CrI
The characteristic absorption of the incyanate group of l' disappears, and 1750
CIrL 1 is the stretching vibration of the carbonyl of the oxazolidone ring, 1700α-1 is the stretching vibration of the carbonyl of the isocyanate ring, 3050.920.810°1250CIr
A characteristic absorption of the epoxy group appeared in L-1, and it was confirmed that oxazolidone isocyanate having an epoxy group at the end was produced.

When the epoxy equivalent of the resin component of this product was measured,
The epoxy equivalent was 340.

13CBi' of meccrylic acid was added to 630 g of this resin solution.

Add 6 g of benzyltriethylammonium chloride, 13
When the temperature was raised to 5°C and the reaction was carried out for 2 hours, an unsaturated polyester solution (4) with an acid value of 3 was obtained.

Using the unsaturated polyester obtained here, a photocurable resin composition as shown in Table 1 was obtained.

Each of the above samples was applied to a thickness of approximately 200 μm on a galvanized iron plate, and after removing the solvent at 80° C. under reduced pressure, 2.
When irradiated with light from a 5KW mercury lamp for 30 seconds at a distance of 20CIrL, it showed excellent chemical resistance and solvent resistance.
A cured film with excellent heat resistance (softening temperature, high temperature strength) was obtained.

In addition, a coating peeled off from an iron plate for zinc was used in the test.

Example 2 In a flask similar to Example 1, 80 g of diphenylmethane diisocyanate, 0.5 g of tetraethylammonium bromide, and 100 g of xylene were placed in 400.9 epoxy resin (Dow Chemical Co., Ltd. trade name DER332), and reacted at 140°C for 2 hours. Ta.

In the infrared absorption spectrum of the reaction product, the absorption of incyanate as a raw material disappears and a new value of 1750 cm-' is observed.

Absorption of oxazolidone and isocyanurate rings appeared at 1700crfL-1.

Also 3 350cm - Mi 1250cm -! 920m
-j 820crn-' epoxy group absorption remained.

The epoxy equivalent of the resin component of this reaction product was measured and found to be 240.

85 g of acrylic acid, 1 g of fumaric acid, and 1.2 g of lithium chloride were added to 580 g of this resin solution, and after reacting at 140°C for 2 hours, xylene was removed under reduced pressure to obtain a mixture with an acid value of 5 and a semi-solid state at room temperature. An unsaturated polyester (5) was obtained.

Using the unsaturated polyester (B) obtained here, Table 3
A photocurable resin composition was prepared as follows.

Each sample was coated on a galvanized iron plate to a thickness of about 200μ, and then placed at a distance of 15 meters from a 2.5KW mercury lamp.
When irradiated for 0 seconds, a strong cured film with excellent chemical resistance and solvent resistance, and also good heat resistance as shown in Table 4 was obtained.

Note that the test was conducted in the same manner as in Example 1.

Example 3 In a flask similar to Example 1, 481 epoxy resin (salt Epon 1001 manufactured by Shell), 87 g of tolylene diisocyanate, 150 g of styrene, 6 g of tetraethylammonium iodide, and 0.0 g of hydroquinone were added. ! 120℃
It reacted for 2 hours.

In the infrared absorption spectrum of the reaction product, absorption of incyanate disappeared, absorption of oxazolidone and incyanurate rings appeared, and absorption of epoxy group remained.

The epoxy equivalent of this reaction product was 526.

Add 124 g of methacrylic acid and 8.8 g of benzyltriethylammonium chloride to 760 g of this reaction product, and add 1'
The reaction was carried out at 20° C. for 2 hours to obtain an unsaturated polyester having an acid value of 3.

2 parts of benzoin isobutyl ether, 1 part of benzoyl peroxide, and 120 parts of neopentyl glycol dianorelay were added to 100 parts of this unsaturated polyester to obtain a photocurable unsaturated polyester resin composition.

This photocurable resin composition was placed on a galvanized iron plate to a thickness of approximately 200 mm.
Apply it so that it becomes μ, 3. 20cr/1. from OKW xenon lamp. When irradiated for 30 seconds at a distance of , a strong cured film with excellent chemical resistance and solvent resistance was obtained.

The curing temperature of this film is 147℃, and the draw strength is at room temperature (2
7.3 kg/mt at 5℃)? t, 6.4 kg/- at high temperature (125°C), and almost no decrease in strength was observed even at high temperature.

Comparative Example 1 In a flask similar to Example 1, 380 g of epoxy resin (trade name Epon 828, manufactured by Shell), 230 g (trade name Epon 101001, manufactured by Shell), and 215.9 g of methacrylic acid. 8.2 g of benzyl l-IJ ethyl ammonium chloride and 014 g of hydroquinone were added and reacted at 135° C. for 2 hours, resulting in an acid value of 5.

The reaction product was cooled to 60°C and diethylene glycol diacrylate 100.9. 10 g of benzoin ethyl ether was added and thoroughly stirred to obtain a photocurable unsaturated polyester resin composition.

This resin composition was irradiated with light and cured in the same manner as in Example 3.

This cured film has excellent chemical and solvent resistance, and has excellent chemical and solvent resistance.
The drawing strength at temperature (°C) was 6.3 kg/ma.

However, the softening temperature is as low as 125°C, and the softening temperature is high (125°C).
) was also significantly lowered to 1.3 kg/mA.

Claims (1)

[Claims] 1. A terminal epoxy resin having an oxazolidone ring and an incyanurate ring obtained by reacting 1 to 5 equivalents of an epoxy compound with 1 equivalent of an isocyanate compound under a heterogeneous catalyst is treated with an unsaturated basic acid and, if necessary, an unsaturated base acid. A saturated polybasic acid or an anhydrous unsaturated polybasic acid is blended in an equimolar amount of the epoxy group of the epoxy resin and the total carboxyl group of the acid, and an esterification reaction catalyst and, if necessary, a polymerization inhibitor, a solvent, or Unsaturated polyester resin composition obtained by heating reaction in the presence of polymerizable hexamer 1.
A photocurable heat-resistant resin composition comprising 0.01 parts by weight or more of a photosensitizer and, if necessary, a polymerizable monomer based on 0 parts by weight.