Modified polyurethane composition and preparation thereof

Abstract

A modified polyurethane composition and its production are disclosed. The process is carried out by taking propylene epoxide s-polyether, castor oil and toluene diisocyanate as raw materials, adding into ethylenediamine polyether, synthesizing A component, accelerating curing time after mixing A with B components, taking 3,-dichloride-4,4,diphenyl bisamine methane as raw materials, adding into vinyl chloride-vinyl acetate copolymer and dimethyl ester methyl phosphonate and producing B component from coal tar pitch. It achieves low cost, simple process, to increase tensile strength, dielectric strength, fire and water resistances of polyaminoresin. It can be used for various coating materials of cable, protective cover of wire and electronic components.

Description

technical field [0001] The invention relates to a polyurethane composition, in particular to a modified polyurethane composition used for wire and cable covering materials and potting and repairing and a preparation method thereof. Background technique [0002] At home and abroad, tetrahydrofuran homopolyether polyurethane is used in the laying of transoceanic submarine cables. It has the advantages of high strength, voltage resistance, and extreme seabed conditions. However, these materials require thermoplastic molding, which is costly and inconvenient to use. In terms of the selection of composite insulating materials, predecessors have tried many methods. For example, the mixing of polyurethane and polycarbonate under melting conditions, the blending of polyether polyurethane and chlorinated polyethylene, the blending of tertiary amine-containing polyurethane and polyvinyl chloride block, etc., have achieved relatively good results in hydrolysis resistance and voltage re...

AI Technical Summary

Problems solved by technology

This invention overcomes the shortcomings of the existing "one-step" production, and has the advantages of short curing time and long storage time, but has low dielectric strength and no flame retardancy, so it is only suitable for insulation and potting of wires and cables below 35KV; The announcement number is 1232850, and the Chinese patent titled "Special Adhesive for Polyurethane Cable Shielding Composite Tape and Manufacturing Method" has the advantages of oil resistance, water resistance, high temperature resistance, and strong adhesion, but poor electrical insulation performance and no flame retardancy The inventor has obtained a Chinese patent with the patent number ZL02154430.1. By adding polyvinyl chloride-vinyl acetate resin additives to the polyurethane prepolymer, the polyurethane has excellent wear resistance, high toughness and chlorine-vinegar copolymer. High electrical breakdown strengths complement each other and reinforce each other, making polyurethane resin products have higher dielectric strength

However, the added vinyl chloride-vinyl acetate resin and polyurethane prepolymer are mixed by physical methods, and phase separation occurs during the preparation and molding of the product, so that the mechanical strength and dielectric strength of the product cannot fully reach the optimum. state