JPS60262816A - Production of polyisocyanurate resin - Google Patents

Abstract

PURPOSE:To obtain a polyisocyanurate resin having good moldability and being excellent in heat and impact resistances, by reacting a specified polyol with a specified organic polyisocyanurate by using a trimerization catalyst in the presence of a defoaming agent. CONSTITUTION:A mixture is formed by mixing a polyol component consisting at least partially of a polyether-polyol of an OH value <=130 (preferably, one terminated with a primary OH) with a defoaming agent (preferably, silicone type) and a trimerization catalyst (e.g., Polycat 41, a product of San Abbott Co.). The obtained mixture is reacted with an organic polyisocyanate (e.g., tolylene diisocyanate) isocyanate index of 200-5,500). This reaction product is cacuum defoamed and poured into a dsired mold and treated at 60-300 deg.C to obtain a polyisocyanurate resin article.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for producing a polyisocyanurate resin having excellent heat resistance and impact resistance.

(Prior Art) Conventionally, polyisocyanurate resins obtained by reacting organic polyisocyanates with polyether polyols in the presence of trimerization catalysts are known to have excellent heat resistance, but impact resistance is poor. There are some disadvantages.

(Object of the Invention) The present inventors have conducted repeated studies to find a method for producing a polyisocyanurate resin having excellent heat resistance and impact resistance, and as a result, they have arrived at the present invention.

(Structure of the Invention) That is, the present invention provides a method for producing a polyisocyanurate resin from an organic polyisocyanate and a polyol in the presence of a trimerization catalyst (a polyether polyol having a valence of 180 or less as at least a part of the ti polyol). use.

(2) The isocyanate index is 200 to 5500, (
3) Reaction in the presence of an antifoaming agent; and (4) heat treatment at a temperature of 60 to 800°C.

In the present invention, as at least a part of the polyol,
A polyether polyol having an OH value of 180 or less, preferably 100 or less, more preferably 60 or less is used. Examples of polyether polyols include compounds having a structure in which an alkylene oxide is added to a polyfunctional compound containing an active hydrogen atom, such as a polyhydric alcohol, a polyhydric phenol, or a polycarboxylic acid.

The above polyhydric alcohols include 1 ethylene glycol, propylene glycol, 1,4-butanediol, 1,6
- Dihydric alcohols such as hexanediol, diethylene glycol, neopentyl glycol and glycerin 9 trimethylolpropane.

8 such as pentaerythritol, sorbitol, and sucrose.
polyhydric alcohols with higher valences or higher; polyhydric phenols include polyhydric phenols such as pyrogallol and hydroquinone, and bisphenols such as bisphenol A; polycarboxylic acids include aliphatic polycarboxylic acids such as succinic acid and adipic acid; Examples include aromatic polycarboxylic acids such as phthalic acid, terephthalic acid, and trimellitic acid. Two or more kinds of the above-mentioned active hydrogen atom-containing compounds can also be used. Examples of the alkylene oxide to be added to the active hydrogen atom-containing compound include ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, styrene oxide, and epichlorohydrin. The alkylene oxides may be used alone or in combination of two or more, and in the latter case, block addition, random addition, or a mixture of both may be used. Preferred among these alkylene oxides are tetrahydrofuran, propylene oxide and/or ethylene oxide. From the viewpoint of reaction, a combination system of propylene oxide and ethylene oxide (usually in a weight ratio of 80:70 to 95:5?!:<To
: 80-90: 10) and a combination system of tetrahydrofuran and ethylene oxide (usually 95:5 by weight)
~80:70 especially 90:10~50:5
0).

Addition of alkylene oxide can be carried out in the usual manner, either without catalyst or in the presence of a catalyst (alkaline catalyst, amine catalyst, acidic catalyst) (particularly in the latter stages of alkylene oxide addition) at normal pressure or under pressure. It is done under pressure.

Among the polyether polyols, preferred are those having a primary OH at the end. The terminal primary polyether polyol usually contains 100% to 50% (by weight) of tetrahydrofuran (hereinafter abbreviated as THF) or ethylene oxide (hereinafter abbreviated as EO) at the terminal, preferably 10
Those with 0% to 20% added (Chitsubud type, balanced type)
can be given. By using a polyether polyol with a terminal primary OH, a polyisocyanurate resin with quick demoldability and high heat resistance can be obtained. D. A polyisocyanurate resin with excellent impact resistance can be obtained. D. The polyether polyol can be used in combination with other polymeric polyols if necessary. be able to.

Examples of other polymeric polyols include polyester polyols, such as condensed polyester polyols obtained by reacting low-molecular polyols with dicarboxylic acids, and polyester polyols obtained by ring-opening polymerization of lactones. The low molecular polyol mentioned above is ethylene glycol.

Propylene glycol, 1,6-hexanediol.

Diethylene glycol, neopentyl glycol.

Diols such as bis(hydroxymethyl)cyclohexane, bis(hydroxyethyl)benzene; trimethylolpropane, glycerin, etc. and mixtures thereof are included. Examples of dicarboxylic acids include succinic acid, glutaric acid, adipic acid, sebacic acid, maleic acid, fumaric acid, phthalic acid, terephthalic acid, dimer acid, and mixtures thereof. Examples of the lactone include ε-caprolactone. OH of polyester polyol
The value is usually 180 or less, preferably 100 or less, more preferably 60 or less. The ratio (weight ratio) of polyether polyol and other polymer polyol (polyester polyol) can be varied, for example, 20:80.
~100:O, preferably 50:50-100
: It is O.

As the organic polyisocyanate used in the present invention, those conventionally used in the production of polyurethane can be used. Specific examples of these include JP-A-57-28
Compounds described in No. 22 and the like can be used. Among these, aromatic diisocyanates are preferred, and TDI and MDI are particularly preferred. These polyisocyanates include crude polyisocyanates such as crude TDI,
Crude MDI or modified polyisocyanates such as liquefied MDI (carposiimide-based, trihydrocarbyl phosphate modified, etc.) or excess polyisocyanate (
TDI.

It can also be used as a free isocyanate-containing prepolymer obtained by reacting MDI, etc.) with a polyol. Examples of polyols used in the production of the prepolymer include polyols having an equivalent weight of 30 to 5,000, such as glycols such as evaporated ethylene glycol and propylene glycol, high-functional polyols such as trimethylolpropane and pentaerythritol, and alkylene oxide adducts thereof. Moreover, polyester polyol can also be used in combination. Among these, those having 2 to 3 functional groups are preferred. The content of free isocyanate groups in the modified polyisocyanate and prepolymer is usually 10 to 30%, preferably 15 to 30%, particularly preferably around 25%.

Antifoaming agents that can be used in the present invention include silicone-based antifoaming agents, such as those with the general formula % (R is H, methyl or/and phenyl l&, n is 1
00 to 10,000), silicone oils (polydimethylsiloxane, polymethylphenylsiloxane, etc.), tri- or tera-alkylsilanes, and silicone alcohols. The viscosity of silicone oil is usually 500 to 10,000 centipoise (
25°C). For more information on silicone oils, see ``Chemistry and Technology of Silicone Systems'' by Walter Knoll, Academic Press, 1968.
press publication).

"Kirk-Othmer: Encyclopedia of Chemical Technology" (2nd edition) Volume 18, 221-2
It is described on page 60. The amount of antifoaming agent added is usually 0001 to 10% per 100 parts of polyisocyanurate resin.
Preferably it is 0.001 to 5%. Addition of this type of antifoam agent helps prevent loss of impact resistance.

As the trimerization catalyst used in the present invention, known ones can be used. Specifically, metal salts of carboxylic acids, such as sodium acetate, lead octylate.

Zinc octylate, cobalt naphthenate, etc.; alkoxides and phenoxides of alkali and alkaline earth metals, such as sodium methoxide.

Sodium phenoxide, etc.; tertiary amines, such as triethylamine, triethylenediamine.

N-methylmorpholine, (dimethylaminomethyl)phenol, pyridine, etc.; quaternary ammonium bases, such as tetraethylammonium hydroxide; imidazoles 1, e.g. imidazole, 2-ethyl-4-
Examples include methylimidazole and the like; organometallic compounds such as tin and antimony, such as tetraphenyltin and tributylantimony oxide. Among these, preferred is a combination system of a metal salt of carboxylic acid and a tertiary amine. The amount of trimerization catalyst used is usually 0.01 to 10 parts, preferably 0.05 to 5 parts, per 100 parts of the organic polyisocyanate. In the present invention, the reaction can be carried out in the presence of other catalysts (tertiary amines, organic tin compounds, organic lead compounds, etc.) and other auxiliary agents, if necessary. Pigments and fillers can also be added if necessary.

In producing the polyisocyanurate m fat in the present invention, the isocyanate index is usually 200 to 5,500, preferably 300 to 5,000. When the isocyanate index is high, the heat resistance is good, but the impact resistance is poor. - A low 10,000 isocyanate index shows the opposite performance.

In producing the polyisocyanurate resin in the present invention, the heat treatment temperature is usually 60 to 300°C, preferably 80°C.
The temperature is preferably 130 to 250°C, more preferably 130 to 250°C. The heat treatment conditions have a great influence on the completion of the resin reaction and the microphase structure. This makes it possible to produce a heat-resistant and impact-resistant polyisocyanurate resin. The heat treatment time is usually 10 minutes to 10 hours, preferably 30 minutes to 8 hours. Heat treatment at low temperatures will result in insufficient heat resistance, and heat treatment at temperatures above 300°C will cause thermal decomposition of the resin, which is not preferred.

The resin manufacturing method according to the present invention may be the same as the conventional one, and the one-shot method and the prepolymer flow method can also be applied.

For the production of the polyisocyanurate resin of the present invention, vacuum degassing molding and RIM molding are useful, but other methods are also applicable.

(Effects of the Invention) The polyisocyanurate resin obtained by the present invention has superior moldability compared to conventional polyisocyanurate resins, and also has excellent 1-thermal impact resistance.

Due to the excellent heat and shock resistance of the resin obtained according to the present invention, it is used in various fields of application, such as switch covers, power distribution boxes, lamp and last accessories, electrical products such as battery boxes, audio products such as speaker boxes, and automobiles. It is extremely useful as aircraft parts such as air filter boxes, ignition distributors, heaters and their boxes.

(Example) The present invention will be explained below with reference to Examples, but the present invention is not limited thereto.

The measurement method is as follows: Heat deformation temperature (load 18.6 kgf/cm'1lsK72
07) Impact strength (IZOT, notched/JI
According to SK7110) Example 1 Propylene oxide (hereinafter abbreviated as PO) to glycerin
Next, EO was adjusted to 1.0 based on the total amount of polyether polyol.
To 100 parts of a polyether polyol with an OH value of 28 obtained by adding % by weight, o and os parts of a silicone antifoaming agent were added.

Add 0.2 parts of Borikatsu l-41 (manufactured by Sun Abbott) as an isocyanurate vehicle and mix uniformly to make 2.
Sumidur PC (NC0% 26%
(manufactured by Sumitomo Bayer Urethane) (isocyanate index: 1240), stirred for 130 seconds, and defoamed under reduced pressure. Pour into a mold preheated to 50-60℃,
Cure in an oven at 0°C for 5 minutes and remove from the mold. then 10
Heat treatment is performed in an oven at 0°C for 1 hour.

A resin having the following properties was obtained.

Heat distortion temperature 125°C Impact strength 11.4 kg-cm/cm Example 2 Polytetramethylene ether glycol 10 with a molecular weight of 3000 and having an OH group at the end obtained by ring-opening polymerization of THF
Polycat 4 is added to 0 parts as an isocyanurate catalyst.
2 (manufactured by Sun Abbott) 01 parts, silicone antifoaming agent 0
Add 1 part to bring the temperature of the liquid to 40°C.

150 parts of the MDI polyisocyanate used in Example 1 was added to the mixture at a temperature of 20° C. and stirred for 30 seconds. After degassing under reduced pressure, it was poured into a mold preheated to 50 to 60°C, cured in an oven at 60°C for 5 minutes, and then demolded.
Heat treatment is performed at ℃ for 3 hours. The properties of the obtained resin were as follows.

Heat deformation temperature 180°C Impact strength 6.3 kg・cm/cm Example 3 Using the raw materials shown in Example 1, preheating temperature 50 to 60°C
The influence of heat treatment conditions was investigated for the resin that was injected into a mold, cured at 60°C for 5 minutes, and then demolded. Reference result example 1 Molecular weight 60 obtained by adding PO to propylene glycol
Example 1: Polyether polyol 10 (1 part, 0.1 part of Polycat 42, 0.1 part of silicone antifoaming agent added, mixed evenly and then adjusted to 20°C. -10000°C, adjusted to 20°C) Mix 400 parts of the same isocyanate (isocyanate index 784), cast into a mold preheated to 60°C, cure at 60°C for 5 minutes, remove the mold, and heat treat at 100°C for 1 hour.The performance is as follows: Although the deformation temperature is good, the impact resistance is extremely poor.

Heat distortion temperature 103℃ Impact strength 1.4kg-cm/cm

Claims (1)

[Claims] (1) In a method for producing a polyisocyanurate resin by reacting an organic polyisocyanate and a polyol in the presence of a trimerization catalyst, (1) at least a portion of the polyol has an OH value of 130 or less; Uses polyether polyol. (2) The isocyanate index is 200-5500, (
3) A method for producing a polyisocyanurate resin, characterized in that the reaction is carried out in the presence of an antifoaming agent, and heat treatment is performed at a temperature of 4360 to 300°C. 2. The manufacturing method according to claim 1. 8. The manufacturing method according to claim 1 or 2, wherein the polyether polyol is di- to trifunctional.