Abstract: High impact polystyrenes and related monovinyl aromatic polymers generally have either a high modulus or good resistance to environmental stress cracking. The present invention is directed at polymeric materials having both a high modulus and good resistance to environmental stress cracking thus enabling the down gauging of parts, and or the use of the materials in new applications. The invention is predicated on the use of one or more, or even all of the following features: a high molecular weight matrix polymer, reduced concentration of elastomeric polymer, or methods that result in large rubber particle size.

Abstract: High impact polystyrenes and related monovinyl aromatic polymers generally have either a high modulus or good resistance to environmental stress cracking. The present invention is directed at polymeric materials having both a high modulus and good resistance to environmental stress cracking thus enabling the down gauging of parts, and or the use of the materials in new applications. The invention is predicated on the use of one or more, or even all of the following features: a high molecular weight matrix polymer, reduced concentration of elastomeric polymer, or methods that result in large rubber particle size.

Abstract: High impact polystyrenes and related monovinyl aromatic polymers generally have either a high modulus or good resistance to environmental stress cracking. The present invention is directed at polymeric materials having both a high modulus and good resistance to environmental stress cracking thus enabling the down gauging of parts, and or the use of the materials in new applications. The invention is predicated on the use of one or more, or even all of the following features: a high molecular weight matrix polymer, reduced concentration of elastomeric polymer, or methods that result in large rubber particle size.

Abstract: High impact polystyrenes and related monovinyl aromatic polymers generally have either a high modulus or good resistance to environmental stress cracking. The present invention is directed at polymeric materials having both a high modulus and good resistance to environmental stress cracking thus enabling the down gauging of parts, and or the use of the materials in new applications. The invention is predicated on the use of one or more, or even all of the following features: a high molecular weight matrix polymer, reduced concentration of elastomeric polymer, or methods that result in large rubber particle size.

Abstract: The present invention relates to a process of producing a molded article from a composition comprising a syndiotactic vinyl aromatic polymer, wherein the molded article has a residual vinyl aromatic monomer content of less than 0.05 per 100 parts syndiotactic vinyl aromatic polymer comprising molding a composition of a syndiotactic vinyl aromatic polymer having a residual vinyl aromatic monomer content of less than 0.3 parts per 100 parts syndiotactic vinyl aromatic polymer, at a temperature of from 265° C. to 305° C. to produce a molded article; and heat treating the molded article at a temperature of 210° C. to 230° C. for at least 2 minutes to thermally initiate free radical polymerization of the residual monomer.

Abstract: The present invention relates to a process of producing a molded article from a composition comprising a syndiotactic vinyl aromatic polymer, wherein the molded article has a residual vinyl aromatic monomer content of less than 0.05 per 100 parts syndiotactic vinyl aromatic polymer comprising molding a composition of a syndiotactic vinyl aromatic polymer having a residual vinyl aromatic monomer content of less than 0.3 parts per 100 parts syndiotactic vinyl aromatic polymer, at a temperature of from 265° C. to 305° C. to produce a molded article; and heat treating the molded article at a temperature of 210° C. to 230° C. for at least 2 minutes to thermally initiate free radical polymerization of the residual monomer.