Polyurethane foam as well as preparation method and application thereof

Abstract

The invention provides polyurethane foam as well as a preparation method and application thereof. The polyurethane foam is prepared from a component A and a component B, wherein the component A is prepared from 100 parts by weight of polyaryl polymethylene isocyanate and 10 to 15 parts by weight of mixed foaming agent; the mixed foaming agent is prepared from methylformate and 10 to 18 parts by weight of toluene diisocyanate and prepolymers thereof; the component B is prepared from 100 parts by weight of premixed polyether polyols, 1 to 2 parts by weight of composite catalyst, 1 to 2.5 parts by weight of water, 1 to 3 parts by weight of surfactant and 10 to 16 parts by weight of multielement foaming agent. According to the polyurethane foam provided by the invention, the problem that the methylformate has a swelling effect on the polyurethane foam is solved by adopting two schemes: firstly, by adopting a multielement foaming agent system, i.e., the foaming agent contains a variety of components, and the swelling effect of the methylformate is weakened by the characteristics of different foaming agents; secondly, by adding the toluene diisocyanate and the prepolymers thereof into the polyisocyanates in the component A, the strength of foam products can be improved.

Description

technical field [0001] The present invention relates to a polymer material, more specifically, to a polyurethane foam and a preparation method and application for preparing the polyurethane foam. Background technique [0002] The foaming process of polyurethane foam prepared by using blowing agents such as chlorofluoroalkane or hydrochlorofluoroalkane is mature. At the same time, the product has low thermal conductivity and good heat preservation effect. However, chlorofluorocarbons and hydrochlorofluorocarbons can seriously damage the ozone layer of the atmosphere, and their use has been banned or restricted by various countries. [0003] Cyclopentane is currently a widely used blowing agent, but limited by the performance of cyclopentane itself, it can no longer meet the new requirements constantly raised in the field of foaming. [0004] Methyl formate has a low atmospheric thermal conductivity and is an ideal blowing agent. However, methyl formate has obvious swelling ...

AI Technical Summary

Problems solved by technology

However, methyl formate has obvious swelling effect on polyurethane materials, and it is difficult to prepare foams with ideal strength and thermal insulation properties. At the same time, methyl formate is unstable in acidic or alkaline environments, and easily decomposes with water to produce formic acid and methanol, which seriously affects foam production. Bubble process control

[0005] It has been reported in literature and patents that methyl formate is mixed with HFC, HCFO, and HFO foaming agents for polyurethane foaming, but most of them require complex process control, such as the selection of polyether in raw materials, the combination of catalysts, and moisture content. Content control, etc., and the overall cost of the foaming system is relatively high, making it difficult to apply in the foaming field