Glass fiber reinforced vinyl chloride polymer products and process for

Abstract

Vinyl chloride (VC) resins, particularly poly(vinyl chloride) (PVC) and chlorinated poly(vinyl chloride) (CPVC) are reinforced with glass fibers which have been sized with a particular aminosilane coupling agent and an alkylene oxide-containing film former. This combination of sizing components, among all others, generates allylic Cl atoms in the VC chain of the polymer. Though the VC resin contains an adequate amount of stabilizer to counter the formation of such allylic Cl atoms in the mass of the resin, enough are generated near the surface of the glass to cause a reaction with the aminosilane so as to bond the glass fibers to the VC resin so strongly that a composite only fails in coherent failure. The sizing consists essentially of (i) an aminosilane coupling agent having a reactive amine moiety which upon reaction with the VC resin results in a compound having a peak in a proton magnetic resonance spectra at 5.65 ppm, and (ii) a film former consisting essentially of a polymer having a ring-opened lower alkylene oxide containing from about 2 to about 4 carbon atoms as an essential component in a repeating unit optionally containing another copolymerizable component. The wet strength of the composite is about equal to or greater than the dry strength of an identical composite which has no film former in the sizing.