Abstract: Thermoformed trays prepared from a blend of 90 to 99.9 percent of polyethylene terephthalate resin, a small amount of sodium ion, and a small amount of wax exhibit effective crystallization rates and improved trimming and stacking properties.

Abstract: A process for improving the stability of a polyarylate resin by reducing the terminal carboxyl acid group concentration of the polyarylate resin, the process being comprised of melting a mixture of the polyarylate resin and an aromatic carbonate capping agent and reacting the mixture under heat and, if necessary, vacuum until the concentration of the terminal carboxyl acid groups is reduced to less than that of the polyarylate resin prior to end-capping. The process also results in a polyarylate resin with a decreased flammability rating when the aromatic carbonate capping agent is bromine substituted.

Abstract: A filament-wound pressure vessel constructed of a rigid composite of an epoxy resin matrix reinforced with continuous filaments of a p-aramid coated with an adhesion modifier.

Abstract: A rigid composite of an epoxy resin matrix reinforced with continuous filaments of a p-aramid coated with an adhesion modifier.

Abstract: Aramid fiber is coated with certain sulfonyl azides to improve adhesion to polymer matrices.

Abstract: Cement product reinforced with p-aramid or acrylic fiber coated with certain sulfonyl azides.

Abstract: Copolyesters useful for fibers from certain monosubstituted hydroquinones, terephthalic acid and certain substituted benzophenones.

Abstract: Coating of aramid filaments with certain polyfunctional aziridines increases interlaminar shear strength of unsaturated polyester matrix composites.

Abstract: Acrylonitrile polymers containing at least 91% by weight acrylonitrile are spun from solutions having a polymer concentration of 38 to 75% by weight. Useful polymers have an intrinsic viscosity of 0.6 to 2.0, most preferably 0.9 to 1.1, 7 to 23 .mu.eq./g. enolizable groups after mild acid treatment, 15 to 70 .mu.eq./g. thioether ends derived from a water insoluble mercaptan and less than 3 .mu.eq./g. oxidizable hydrolysis fragments.

Abstract: Polyester fiber can be dyed with indigo so as to possess washdown and fading characteristics similar to indigo-dyed cotton fibers provided they are first coated with a polymeric salt having the following repeating units: ##STR1## with from 0 to 75 mol % of another ethylenically unsaturated monomeric unit,or ##STR2## wherein R is hydrogen, methyl or ethylR.sup.1 is a divalent hydrocarbon radical of 1 to 4 C atomsR.sup.2 and R.sup.3 are lower alkyl (from 1 to 4 C atoms)R.sup.4 is hydrogen, hydroxyethyl or lower alkyl (from 1 to 4 C atoms)X.sup.- is an anionPreferably, in Formula A, R.sup.1 contains 2 carbon atoms; R.sup.2 .dbd.R.sup.3 .dbd.R.sup.4 .dbd.methyl; and X.sup.- is 83 mol % CH.sub.3 SO.sub.4 -- and 17 mol % C.sub.18 H.sub.35 SO.sub.4 --.