JPS5825686B2 - Thailand - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heatable resin composition comprising a resin composition based on a resin containing a reactive hydrogen atom and a novel incyanate.

Conventionally, toluylene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, or 3 moles of these diisocyanates are added to 1 mole of trimethylolpropane to resins containing reactive hydrogen atoms, such as polyester resins, polyvinyl formal resins, and epoxy resins. In order to improve the heat resistance, chemical resistance, etc. of the resin, polyisocyanates such as triisocyanates, or stabilized polyisocyanates obtained by stabilizing these polyisocyanates with stabilizers such as phenol, cresol, and xylenol, may be added. It was publicly known.

However, even when such an isocyanate is added to a resin composition based on a resin containing a reactive hydrogen atom, a dramatic improvement in heat resistance cannot be expected.

Therefore, in order to improve the heat resistance of resin compositions, there has been a demand for a new incyanate that can significantly improve the heat resistance.

In response to such requests, the present inventors conducted intensive research on the development of new incyanate compounds in order to significantly improve the heat resistance of resin compositions based on resins containing reactive hydrogen atoms. This is what I found as a result.

That is, the present invention is an incyanate obtained by adding at least an equimolar amount of polyisocyanate to maleic anhydride to a resin composition based on a resin containing a reactive hydrogen atom, and heating the mixture to a temperature of 100° C. or higher. Alternatively, a stabilized product of the polyisocyanate is blended.

The gist of the present invention is to use a special incyanate obtained by reacting maleic anhydride with a polyisocyanate. Examples of the polyisocyanate include toluylene-2,4-diisocyanate and hexamethylene. Diisocyanate, diphenylmethane 4゜4' diisocyanate, diphenyl ether 4゜4' diisocyanate, diphenyl sulfone 4゜4' diisocyanate, diphenylmethane 8,4゜4'
Such as triisocyanate and xylylene diisocyanate.

Stabilized isocyanates prepared by adding phenol, cresol, ethyl alcohol malonic acid ester, etc. to these polyisocyanates can also be used.

Regarding the reaction product of maleic anhydride and the above-mentioned polyisocyanate, the anhydride group of maleic anhydride and the incyanate group of polyisocyanate are heated to react at 100°C or higher to form a 5-membered product. A ring imide is formed to become an isocyanate containing a maleic acid imide group, and when heating is continued, the unsaturated bonds of the maleic acid imide groups react with each other to convert it into a high molecular weight polyisocyanate.

Therefore, the new isocyanate obtained in this way contains an unsaturated double bond, an isocyanate group that can react with a reactive hydrogen atom, and a 5-membered ring imide group that improves heat resistance, so it has extremely excellent heat resistance and chemical resistance. It has excellent performance.

In addition, in the present invention, the reason why the amount of polyisocyanate is limited to the equivalent molar amount or more with respect to maleic anhydride or maleic acid monoester is that if it is less than the equivalent molar amount, a maleimide compound that does not contain an isocyanate group is likely to be formed. This is because it becomes difficult to obtain a compound containing an isocyanate group that is highly reactive with active hydrogen and a maleimide group that improves various properties.

The above reaction must be carried out at a temperature of at least 100°C or higher, and the reason for this restriction is 1.
This is because if the temperature is lower than 00°C, the imidization reaction will not proceed sufficiently and the imide ring formation reaction will become insufficient.

Note that it is desirable that the temperature is usually in the range of 100 to 250°C.

Furthermore, when maleic anhydride is reacted with polyisocyanate or stabilized polyisocyanate in the present invention, a uniform reaction can be carried out by using a solvent such as N-methylpyrrolidone, dimethylacetamide, cresol, or xylenol. By using tin octylate, zinc octylate, and ferric acetylacetone as catalysts, the reaction can be carried out rapidly.

Next, examples of the present invention will be described.

Example 1 98 g of maleic anhydride and 174 g of a mixture of 2,4- and 2,6-toluylene diisocyanate were added with 572 g of cresol and 0.59 stannous octylate to give 195 g.
The temperature was raised to .degree. C. over 3 hours, and the reaction was continued at this temperature for 4 hours to obtain a transparent viscous solution (referred to as solution A).

In order to confirm whether or not Solution A contained incyanate groups as well as imide groups, the solution was applied to a salt plate and dried at 190°C for 20 minutes, and then the infrared absorption spectrum was measured. , about 1710crIL-1 and about 1780cIfL-1, and an absorption band caused by the isocyanate group at about 2300CrfL-1.

Then, 400 g of the above solution A and 3 moles of toluylene diisocyanate were added to 200 g of a polyester resin containing about 9 reactive hydroxyl groups synthesized using phthalic anhydride, adipic acid, and trimethylolpropane. 100 g of stabilized polyisocyanate (hereinafter referred to as B isocyanate), which was added to 1 mole and then stabilized the incyanate group with phenol, was added and mixed, and this was dissolved in 600 g of cresol,
A uniform paint was obtained.

This coating was applied to a copper wire with a diameter of 1.0 mm and baked at 400° C. six times to obtain an insulated wire with a coating thickness of 40 μm.

The results of measuring the performance of the insulated wire thus obtained are as follows:
As shown in the table.

Comparative Example 1 300 g of B isocyanate alone was added and mixed to 200 g of the same polyester resin as that used in Example 1, and this was dissolved with 300 g of cresol to obtain a uniform paint.

This paint was applied to a copper wire with a diameter of 1.5 mm and baked at 400° C. six times to obtain an insulated wire with a coating thickness of 41 μm.

The results of measuring the performance of the insulated wire thus obtained are also listed in Table 1.

Example 2 Epoxy resin (Epicoat 11009 manufactured by Shell, USA)
300, solution A in Example 1, 400I, and 150 g of B isocyanate were dissolved in cresol 100 (Bi') to obtain a paint.

This coating was applied to a copper wire with a diameter of 1.0 mm and baked at 400° C. seven times to obtain an insulated wire with a coating thickness of 40 μm.

Comparative Example 2 Epoxy resin (Epicoat 11009 manufactured by Shell, USA)
300 to 50 cresol solution of B isocyanate 18
0I was added and dissolved in 1000 g of cresol to obtain a uniform paint.

This coating was applied to a copper wire with a diameter of 10 mm and baked at 400° C. seven times to obtain an insulated wire with a coating thickness of 40 μm.

The insulated wires obtained in Example 2 and Comparative Example 2 were wound around mandrels of various diameters and heated at 170°C.
As a result of performing heat treatment for a period of time and measuring the presence or absence of cracks, it was found that the insulated wire (Example 2) made of the resin composition of the present invention was 1.
While the insulated wire made of the conventional resin composition (Comparative Example 2) showed good values at the double diameter, it showed good values at the triple diameter.

Therefore, it was shown that the insulated wire made of the resin composition of the present invention has far superior heat resistance properties.

Example 3 3150 g of cresol was added to a mixture of 98 g of maleic anhydride and 804 g of a trimeric phenol adduct of toluylene diisocyanate, the temperature was raised to 190°C, and the reaction was continued at this temperature for 5 hours to form an imide. A stabilized isocyanate solution containing groups (referred to as C solution) was obtained.

On the other hand, a polyurethane consisting of an imide group-containing polyester resin, diphenylmethane diisocyanate, and ethylene glycol in equal moles, trimellitic acid, dimethyl terephthalate, and an equivalent amount of ethylene glycol and glycerin in a molar ratio of twice the amount of diphenylmethane diisocyanate in the polyurethane. To a resin solution obtained by adding and heat-reacting the resultant to a 351:f6 concentration with cresol, add the above C solution at a ratio of 200 g to 1 kg of the resin solution to obtain a uniform paint. Ta.

This paint was applied to a copper wire of 1m7IL and baked at 400°C six times to obtain an insulated wire with a film thickness of 45μ.

Comparative Example 3 Only the imide group-containing polyester resin solution in Example 3 was applied onto a 1 mm copper wire and baked at 400° C. six times to obtain an insulated wire with a coating thickness of 45 μm.

The results of measuring the characteristics of the insulated wires obtained in Example 3 and Comparative Example 3 are shown in Table 2.

As detailed above, the heat-resistant resin composition of the present invention has extremely excellent heat-resistant properties and is extremely useful industrially in insulating paints, insulated wires, and other fields.

Claims (1)

[Claims] 1. Incyanate or the polyisocyanate obtained by adding at least an equimolar amount of polyisocyanate to maleic anhydride to a resin composition based on a resin containing a reactive hydrogen atom, and subjecting the mixture to a heating reaction at 100° C. or higher. A heat-resistant resin composition characterized in that it contains a stabilizer of.