Alkali metal salts of cross-linked polymeric microgels as nucleating agents for polyethylene terephthalate molding compositions and method for molding

摘要

Disclosed are nucleating agents for polyethylene terephthalate molding compositions comprised of alkali metal salts of carboxylic acid- containing polymeric microgel particles which are prepared by polymerizing in aqueous emulsion a monomer mixture containing about 5 to 50 percent by weight of polymerizable carboxylic acid monomers, up to 10 percent of a multifunctional crosslinking monomer and one or more carboxylfree relatively water insoluble polymerizable vinyl monomers.