Resin compositions with high thermoplastic loading

摘要

Uncured thermosetting resins are loaded with relatively high amounts of solid thermoplastic resin particles to form a resin precursor. The resin precursor is heat treated so as to produce an uncured resin composition wherein the thermoplastic resin particles become substantially dissolved in the thermosetting resin without causing cure of the resin mixture. Heat treatment of highly loaded thermosetting resins in accordance with the present invention provides uncured resin compositions that are well suited for use in fabricating composite structures and particularly prepreg for use in lightning protection surface coatings.

主权项

1. A method for forming a surfacing layer on an underlying structure, said method comprising the steps of:
providing, a first layer comprising an uncured resin precursor which comprises a thermosetting resin component that comprises an epoxy resin, a curing agent for said thermosetting resin component, a first thermoplastic resin component comprising a first dissolved thermoplastic resin and a second thermoplastic component comprising thermoplastic particles wherein said first dissolved thermoplastic resin and said thermoplastic particles are present in amounts such that said uncured resin precursor has a viscosity of between 20,000 and 100,000 poise at 30°C. and wherein the total amount of said first and second thermoplastic components is from 20 to 60 weight percent of the total weight of said uncured resin precursor; heating the uncured resin precursor in said first layer to a sufficient temperature for a sufficient time to substantially dissolve said thermoplastic particles without cluing said thermosetting resin component to thereby form said first layer into a second layer comprising uncured resin which has a viscosity that is substantially higher than said uncured resin precursor; applying said second layer to an underlying structure to form an outer layer of uncured resin; and curing said outer layer of uncured resin to form said surfacing layer on said underlying structure.