JPS61223014A - Production of modified polyester polyol - Google Patents

Abstract

PURPOSE:A polyester polyol bearing terminal hydroxyl with a specific molecular weight is combined with a vinyl monomer and a vinyl polymerization catalyst and they are heated to produce the title modified product which can shorten time, when used as a starting material for polyurethane foam moldings. CONSTITUTION:(A) 100pts.wt. of hydroxyl-terminated polyester polyol such as polycondensation products between adipic acid and ethylene glycol, are combined with (B) 1-10pts.wt. of vinyl monomer such as styrene, then with (C) 0.01-1wt%, based on the total of components A and B, of a vinyl polymerization catalyst such as azobisisobutyronitrile. Then, they are uniformly stirred and preferably heated at 50-100 deg.C for 2-10hr to give the modification product.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for obtaining a modified polyester polyol by heating a mixture of a polyester polyol and a vinyl monomer in the presence of a catalyst.

The modified polyester polyol in the present invention is used as one of the raw materials for producing polyurethane foam, particularly polyurethane foam elastomer. In this case, raw materials for the production of functional materials include polyisocyanates, chain extenders or crosslinking agents, blowing agents, catalysts, etc., and these raw materials are used to produce molded products by a two- or three-component reaction molding method.

In the production of polyurethane foam molded products using polyester polyols according to the prior art, it has been difficult to shorten demolding time in order to improve productivity due to various constraints. Although it is possible to shorten the demolding time to some extent by increasing the amount of catalyst, increasing the temperature of the reactants, and increasing the temperature of gold, there are limits.

In other words, when increasing the amount of catalyst, for example, there are drawbacks such as shortening the pot life and poor flow of the reaction liquid in the mold, resulting in underfilling, so quantitative restrictions should be placed. receive.

In order to shorten demolding time, it is possible to change the organic acid in the polyester polyol composition from the conventional adipic acid to a more rigid composition such as phthalic acid, or to introduce a polyfunctional polyol such as triol into the glycol composition. Although this achieves the objective to some extent, the resulting molded product becomes hard, which is not preferable.

The present inventor investigated whether or not it was possible to shorten the demolding time by partially modifying the polyester polyol without impairing its original characteristics, and as a result, it was discovered that vinyl monomers such as styrene and acrylonitrile could be mixed into the polyester polyol. It was discovered that a modified polyester polyol obtained by adding a catalyst such as azobisin butyronitrile and heating can shorten demolding time, leading to the present invention.

That is, the present invention provides a polyester polyol characterized in that 1 to 10 parts by weight of a vinyl monomer and a vinyl polymerization catalyst are added to 100 parts by weight of water [1-terminated polyester polyol] with a molecular weight of 200 to 30 CO, and heated. The present invention relates to a method for producing a modified product.

As the polyester polyol that can be used in the present invention, all kinds of polyester polyols used in polyurethane resins can be used. In particular, polyester polyols for polyurethane foam elastomers include condensation reaction products of organic acids such as dibasic acid, fumaric acid, phthalic acid, and the like, and glycols such as ethylene glycol, butylene glycol, and glycol. These raw materials may be used alone or as a mixture of two or more.
A6゜The molecular weight of polyester polyol is 200-30
00 is preferred. If it is smaller than 200, the molded product will not have flexibility, and if it is larger than aooo, the viscosity of the polyester polyol will be high and workability will be reduced, which is not preferable. Polyester polyols having these molecular weights are used alone or as a mixture of two or more types of molecular weights. Low molecular weight compounds are often used as a mixture with higher molecular weight compounds rather than alone.

Vinyl monomers that can be used in the present invention include styrene, acrinitrile, methyl methacrylate, etc., and the amount added is preferably 1 to 10 parts by weight per 100 parts by weight of the polyester polyol. In this case, if the amount is less than 1 part by weight, the demolding effect will not clearly appear.
If it exceeds the weight part, the proportion of the vinyl part becomes large, and the characteristics of the polyester polyol are not exhibited, which is not preferable.

As the vinyl polymerization catalyst that can be used in the present invention, radical polymerization catalysts such as 7zobisisoptyl tolyl and penzoyl peroxide are preferred, and the amount added is 0 to the total of polyester polyol and vinyl monomer. .01 to 1.0% is suitable.

When polyester polyol, vinyl monomer, and M medium are weighed, stirred uniformly, and heated, the heating conditions are 50 to 1.
The modified polyester polyol of the present invention can be obtained at 00°C for 2 to 10 hours.

The modified polyester polyol obtained by the present invention is produced by mixing polyol, chain extender, catalyst, blowing agent, and various other additives with organic polyisocyanate substantially simultaneously, especially in a polyurethane foam elastomer In the one-shot method, a catalyst, a blowing agent, and various other additives are added to a reactant (prepolymer) having an incyanate group at the end obtained by reacting an organic polyisocyanate with a polyol having a chemical equivalent or less. mix,
A prepolymer method in which reaction foaming is performed, and a coexisting compound (semi-prepolymer) of a reactant of a polyol and an organic polyisocyanate having an incyanate group at the end and a free organic polyisocyanate (semi-prepolymer), a polyol, a catalyst, a blowing agent, and others. It can be used as a polyol component in a semi-prepolymer method, etc., in which a mixture of various additives is added, mixed, and reacted and foamed.

By using the modified polyester polyol obtained in the present invention, demolding time can be shortened, liquid flowability (the ability to fill every corner of the mold with liquid) improved, adhesion, chemical resistance, weather resistance, etc. It is used in reaction molding fields such as various types of rubber, various types of belts, various types of anti-vibration rubber, shoe soles, backings, etc.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1゜21!0 Diethylene glycol 7 dipate (hydroxyl value 54.6, molecular weight 2050, hereinafter DE
A2000) 1852F, Acrynitrile 47
．． Measure out 1.9F of 5f, 7zoisopti nitrile (hereinafter abbreviated as AIBM) and add 60% N while flowing gas.
The mixture was reacted at ~85°C for 4 hours and vacuum treated at 80°C and 60 mHf for 45 minutes to obtain 1890t of modified polyester polyol A. The hydroxyl value was 53.7.

Example 2 Measure out DEA200018052°Styrene 9591AIBN1.9F into a 21°F four-loaf flasp, and measure N.

A reaction was carried out at 70 to 85° C. for 5.5 hours while flowing a gas to obtain modified polyester polyol B of 19002. The hydroxyl value was 51.4.

Example 3 2104 ethylene glycol/1.4 butylene glycol 7 dipate coester (hydroxyl group 11i)
107, molecular weight 1050, hereinafter abbreviated as EBA1000)
1755f, methyl methacrylate 45f, AIBN
Measure out l, 8f and add %N, 65 to 8 while flowing gas.
The reaction was carried out at 0° C. for 4 hours, and a modified polyester polyol C of 18009 was obtained. The hydroxyl value was 103.

Example 4゜2I! 4-mouth 7 Lasco EEBA1000 17552
, Styrene 45? , A I B N 1.8 f was weighed out and reacted at 70 to 85° C. for 5 hours while flowing nitrogen gas to obtain a 1 soor modified polyester polyol. The hydroxyl value was 102.

Examples & 2I! DEA2000 1767t on four Lofra X2
1 Styrene 133P, AIBNl, and 9F were weighed out and reacted at 73 to 80°C for 6 hours while flowing Vegas.
A modified polyester polyol E of 8931 was obtained. Hydroxyl value f! , it was 51.0.

Comparative example 1゜2/104゜a? S:i DEA2000 1890
．． 521 styrene 9.5f% AIBN 1.9F was weighed out and reacted at 82 to 85°C for 6 hours while flowing nitrogen gas to obtain a modified polyester polyol F of 19002. The hydroxyl value was 54.6.

Comparative example 2゜21 (Q4 ay5*1 CDEA2000 1672
f1 styrene 2289. AIBNl, measure 9f%
A reaction was carried out at 75 to 85° C. for 5 hours while flowing nitrogen gas to obtain a modified polyester polyol G of 1890f.

Since this product had a viscosity of 100,000 centipoise or more at 25°C, a demolding test could not be performed.

Application Example 1 Using the modified polyester polyol obtained in Example 1.2.5 and Comparative Example 1 and DEA2000 as Comparative Example 3, a foamed elastomer was molded according to the following formulation.

Part A modified polyester polyol 87 parts by weight ethylene glyfur 12 triethylenediamine (hereinafter referred to as TEDA and l1t50.4 water)
0.35 Liquid B An NCO-terminated prepolymer (NCO content 8.8%) prepared from diphenylmethane diisocyanate and ethylene glycol adipate with a molecular weight of 2 ooo. 100 parts by weight of a mixture of Liquid A heated to 40'C.
40℃f1B liquid at NCO/OH4 ratio of 1.0C
A total of 9 samples were mixed and both solutions were poured into a 10 x 140 x 200 iron mold heated to 40°C. A wax-based mold release agent was applied to the mold in advance. The injection amount was adjusted so that the density of the molded product was 0.6 f/cdE.

After a certain period of time after injection, the mold was demolded and the demoldability was examined. The demolding time was determined and the results are shown in Table 1.

Application Example 2 Using the modified polyester polyols obtained in Examples 3 and 4 and EBAlooO as Comparative Example 4, a foamed elastomer was molded according to the following recipe.

Part A Polyester polyol modified product 83 parts by weight 1.4 Butylene Glyfur 16'
I'E D A
0.4 water
NCO-terminated prepolymer (NGO-containing J) used in 0.35B liquid application example 1
ll 8.8%) 100 parts by weight of a mixture of liquid A heated to 40°C and 9.4 parts by weight
Mix liquid B at 0°C with NGOof (measured so that the ratio is 1.0) and heat it to 40°C.
It was poured into a 10x140x200 mold. A wax-based mold release agent was applied to the mold in advance. The injection amount was adjusted so that the density of the molded product was 0.6 f/eel. After a certain period of time after injection, the mold was removed and the demolding time was determined. Table 2 shows the results.

Table, 2

Claims (1)

[Claims] A method for producing a modified polyester polyol, which comprises adding 1 to 10 parts by weight of a vinyl monomer and a vinyl polymerization catalyst to 100 parts by weight of a hydroxyl-terminated polyester polyol having a molecular weight of 200 to 3,000, and heating the mixture.