JPS5876416A - Manufacture of urethane-modified isocyanurate foam - Google Patents

Abstract

PURPOSE:To obtain titled foam of outstanding low-temperature curability by the reaction between a specific two sorts of polyols and an aromatic polyisocyanate in the presence of a foaming agent, catalyst, and surface active agent. CONSTITUTION:The objective foam can be obtained by the reaction between (A) a polyol mixture comprising (i) 10-50wt% of a polyol with a hydroxyl number of 40-60mgKOH/g prepared by the reaction, using glycerin as an initiator, between (a) >=60wt% of ethylene oxide and (b) <=40wt% of propylene oxide and (ii) >=50wt% of a second polyol with a hydroxyl number of 30-470mgKOH/g prepared by the reaction, using ethylenediamine as another initiator, between (c) 50wt% of ethylene oxide and (d) 50wt% of propylene oxide and (B) an aromatic polyisocyanate in the presence of (C) a foaming agent, a catalyst, and a surfactant. Here, 2.0<the components B/A (equivalent ratio) <4.0.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides I11!, a urethane-modified incyanurate foam with excellent curing properties at low temperatures. It is related to the manufacturing method.

In general, isocyanurate foam exhibits excellent flame resistance and heat resistance, but on the other hand, it has poor reactivity compared to general 7-ohm urethane, and often requires heating during foaming, especially when sprayed. If the surface is cold during foaming, etc., the curing is insufficient. 4@- The foam may peel off depending on the condition.

The present authors have carefully considered these shortcomings and have come up with this proposal.

That is, the present invention relates to the production of incyanurate foam using polyols, aromatic polyisocyanates, blowing agents, catalysts, and surfactants as main raw materials. and the hydroxyl value obtained from 40 to 60
q KOH/t polyol (hereinafter referred to as polyoleum) and ethylene diamine as initiators to react ethylene oxide and propylene oxide at a rate of 50 Arashiden each to obtain water with an Al value of 430 to 4 F0 KOH.
/y polyol (hereinafter referred to as polyol B), the amount of polyol is 10 to 50 ml based on the total polyol, and the amount of polyol B is 50 times! are used in combination in a ratio of 1 or more, and the excess polyinocyanate and polyol are adjusted to an equivalent ratio of polyisocyanate and polyol of 2 (polyinocyanate/polyol), and a three-cap acupuncture needle is used as the main catalyst, and foaming is performed. As the agent, a blowing agent which reacts with a low boiling point inert solvent and/or incyanate to generate carbon dioxide gas is used.

If the equivalence ratio is less than 2, the heat resistance and flame resistance will deteriorate significantly, and the foam will not shrink.If the equivalence ratio is 4 or more, the foam will not collapse and the foam will not be stable.

Polyol B is generally known as a polyol for rigid urethane spray foam materials.9 Polyols with a hydroxyl value outside the range of 430-470-KOH/f have poor foaming properties; things are commonly used. However, when polyol B is used alone, it has poor adhesion to the substrate when sprayed at low temperatures, and is not practical at low temperatures of about 5°C or lower. Turnip price is 40-60 KOH/t
is preferable, and exceeding 60×oa7/r is not preferable because the adhesiveness of the foam deteriorates. Tomo 40kton
/ t K-values are generally not put into practical use.

The present invention makes it possible to produce an isocyanurate foam that exhibits mildew properties at low temperatures using two polyols as described above.

The polyinocyanate that can be used in the present invention can be any polyinocyanate that is used in the production of ordinary urethane foam, but 4,4'-diphenylmethane diisocyanate and its crude products are especially good in terms of heat resistance and flame resistance. In good condition.

Further, the trimerization catalyst is not limited at all in the present invention, but there are 2! , 4.6) Squirrel (Simethyla Z
It is effective to use phenol, alkali metal salts of carboxylic acids, 1,8-cyaz-bicyclo(5゜4.0)kundecene-2'7, etc. alone or in combination with a certain percentage of QII'i. .

Examples of blowing agents include reactive blowing agents, and inert low-boiling solvents such as trichlorotetramonofluoromethane, methane chloride, and methylene chloride.

Any surfactant that is effective for urethane foam can be used.

The present invention will be described below with reference to embodiments, but it goes without saying that the present invention is not limited to the following embodiments.

〔Test method〕

(1) Flame resistance test (flame penetration test) U.S. Bureau of Mines test standards Bur@au of Ming
Report of Investigation
A 6366 (1964) method was used.

(Heat resistance test (130°C, body temperature change) 100Xlo
OX50% 07#-mu 1301? , during opening a
After 4 hours of filtration, the rate of change in the original volume was measured.

[Raw materials used]

Polyol B: Polyol B: 0Hv48T19KOH/l polyol obtained by reaction addition of 70% ethylene oxide and 30% propylene oxide using glycerin as an initiator Polyol B: Reaction addition of 9ox*% ethylene oxide and 1oft propylene oxide using glycerin as an initiator OHV 504 KOH/f polyol Polyol C: Polyol C: OHV 470 qKOH/l polyol D: Polyol D: Sucrosamine paste 01IV 53011f KOH/lo polyol polyol I1. O HV 760 wg KOH/t polyol polyol F = O HV 200 M9 KOH/f obtained by reaction adding ethylene oxide fluoride and propylene oxide 30 ts using glycerin as an initiator. Polyol Examples 1 to 5 The reaction mixtures shown in Table 1 were spray-foamed using a gasmer foaming machine model yy and sprayed onto a plywood board using ambient vaporization at a room temperature of 10°C. Comparative example with good form 1-3

Claims (1)

[Claims] In order to produce urethane-modified incyanurate foam using polyol, aromatic polyisocyanate, blowing agent, catalyst and surfactant as main raw materials, as polyol,
Nonahydroxyl value 40-6011f obtained by reacting at least 60 weight of ethylene oxide and 40 weight or less of propylene oxide using glycerin as an initiator.
KOH/t polyol to total polyol
~50 heavy lid-1 Furthermore, using ethylene diamine as an initiator, 50 weight each of ethylene oxide and propylene oxide were reacted to obtain a large hydroxyl group *tSO~ No. 10
If a polyol of 11fIon/t is used in an amount of 50% by weight or more based on the total polyol, and the equivalent ratio of polyisocyanate to polyol is in the range of 2.0<polyincyanate/polyol<number, 0, then the manufacturing method of 15. .