Abstract: There is disclosed an improved modified polymer suitable for use in making hollow containers by conventional extrusion blow molding. It is a specific type of end-capped and branched polyethylene terephthalate polymer or copolymer. In the improvement, the end-cap comprises the reacted component of a difunctional acid or alkali metal salt of a difunctional acid having the formula: ##STR1## wherein: X has a valency of 6 and is selected from sulfur, selenium, and tellurium;M is an alkali metal or hydrogen; andY is hydrogen or an aliphatic group containing from 1 to 18 carbon atoms.The preferred difunctional acid is m-sulfobenzoic acid. The product typically contains few large gels having diameters greater than 0.1 mm.

Abstract: There is disclosed an improved modified polymer suitable for use in making hollow containers by conventional extrusion blow molding. It is a specific type of end-capped and branched polyethylene terephthalate polymer or copolymer. In the improvement, (a) the end-cap comprises the reacted component of a monofunctional acid having a normal boiling point or sublimation point less than above about 200.degree. C.; and (b) the monofunctional acid is an aromatic monocarboxylic acid having the formula: ##STR1## wherein: R.sub.3 and/or R.sub.5 is an alkoxy group containing from 1 to 10 carbon atoms; and, the remaining R's are hydrogen. The preferred monocarboxylic acid is m-anisic acid. The product typically contains few large gels having diameters greater than 0.1 mm.

Abstract: There is provided an improved molding resin capable of being molded into an article exhibiting reduced tendency to corrode a copper surface when the molded resin and the copper surface are placed in spaced relationship in a common unventilated atmosphere at elevated temperatures, as measured by the Bell Telephone Laboratories Copper Corrosion Test at temperatures within the range of from 150.degree. to 175.degree. C., wherein the molding resin comprises the combination of (a) a butyleneterephthalate polyester comprising a brominated copolyester as a polymeric flame retardant comprising aromatic halogen groups in a flame retardant amount, and (b) an alkylhydroxyphenylalkanoyl-hydrazine in an amount that is within the range of from 0.05 to 0.3% by weight.

Abstract: There is provided an improved molding resin capable of being molded into an article exhibiting reduced tendency to corrode a copper surface when the molded resin and the copper surface are placed in spaced relationship in a common unventilated atmosphere at elevated temperatures, as measured by the Bell Telephone Laboratories Copper Corrosion Test at temperatures within the range of from 150.degree. to 175.degree. C., wherein the molding resin comprises the combination of (a) a poly(butylene terephthalate) based polymer and aromatic halogen groups in a flame retardant amount, and (b) an alkylhydroxyphenylalkanoyl-hydrazine in an amount that is within the range of from 0.05 to 0.6% by weight, based on the weight of the molding resin, and less than 0.8% by weight based on the polymer.

Abstract: A single screw extrusion process for extruding a mixture of relatively high molecular weight thermoplastic elastomer particles and relatively low molecular weight resin particles, wherein the particulate mixture is supercooled and maintained at temperatures below that which would cause the mixture to agglomerate and stick to the screw until the axial driving forces on the mixture have increased to the extent they will overcome any tendency of the mixture to stick to the screw, thereby assuring steady state extrusion conditions.