Abstract: An aqueous glass fiber sizing composition that includes a polymeric film forming component, at least one silane coupling agent, and one or more lubricants is provided. The polymeric film forming component of the sizing composition includes a silanated polyvinyl acetate, an epoxidized polyvinyl acetate, and a modified epoxy emulsion. In preferred embodiments, the film formers are present in the sizing composition in ratios of 70:25:5, 50:25:25, or 63:18:18 of silanated polyvinyl acetate, epoxidized polyvinyl acetate, and modified epoxy emulsion respectively. Fibers sized with the sizing composition in a sheet molding compound process have improved wet-out characteristics.

Abstract: An aqueous glass fiber sizing composition that includes a polymeric film forming component, at least one silane coupling agent, and one or more lubricants is provided. The polymeric film forming component of the sizing composition includes a silanated polyvinyl acetate, an epoxidized polyvinyl acetate, and a modified epoxy emulsion. In preferred embodiments, the film formers are present in the sizing composition in ratios of 70:25:5, 50:25:25, or 63:18:18 of silanated polyvinyl acetate, epoxidized polyvinyl acetate, and modified epoxy emulsion respectively. Fibers sized with the sizing composition in a sheet molding compound process have improved wet-out characteristics.

Abstract: A sizing formulation and method of making a sizing formulation for fiberglass reinforcement rovings used in phenolic pultrusion are provided. The sizing formulation includes 1-7% of a film forming polymer, 0.3-3.5% of a silane coupling agent, 0.5-3.0% of a nonionic lubricant, and 0.2-3.5% of a cationic lubricant. Optionally, the sizing composition contains up to 3% of a waterborne urethane solution. The sizing composition is highly compatible with phenolic resins used in pultrusion processes and promotes an improved interface and increased compatibility between the individual fibers and the matrix resin. This increased interface results in better mechanical properties so that a fiber reinforced phenolic resin composite part having superior performance characteristics can be formed.