Shell Oil Comapny

The Goodyear & Tire Rubber Company

Donald E Richeson

Walter Francis Johnston

William George Perkins

Robert Henry Vogliano

John E Hrivnak

Timothy P Saupe

Judith A Tweedie

Clem B Shriver

Vernon V Vanis

Hoyt M Wells

William J Determan

Clem Branum Shriver

A method of making a polyethylene terephthalate/polyolefin blend for sheeting and thermoformed articles which has improved color stability and can be recycled many times. A heat stabilizer is melt blended only with the polyolefin prior to its incorporation into the polyethylene terephthalate. The PET and polyolefin are then blended and extruded into sheeting and subsequently thermoformed into articles useful as microwave oven trays.

Method of manufacturing partially crystalline polyester articles

This invention is a composition, a kit to prepare the composition, cellular sheet made from the composition and thermoformed articles made from the sheet, in which the composition comprises polyethylene terephthalate, sufficient inert gas to give a sheet density of 0.4 to 1.25 gm/cc, a polytetrafluoroethylene nucleating agent and optionally a polyolefin additive and a heat stabilizer.

Cellularized polyesters

This invention is a composition and a kit to prepare the composition and articles made from the composition, which composition comprises polyethylene terephthalate, a nucleating agent having a defined Nucleation Index and optionally a polyolefin and a heat stabilizer. A particularly effective nucleating agent is polytetrafluoroethylene.

Nucleation of crystallization in polyesters

This invention relates to a thermoplastic resin composition which is particularly suitable for use in thermoforming thin walled articles. The thermoplastic resin compositions are comprised of (1) from about 94 to about 99 weight percent polyethylene naphthalate and (2) from about 1 to 6 weight percent of at least one polyester elastomer. The subject invention also deals with thermoforming such thermoplastic resin compositions into articles, such as food trays, having a crystallinity within the range of about 10% to about 40%.

Polyester composition which is particularly suitable for use in

A method of vulcanizing a tubular article by extruding a sheath of unoriented polyethylene terephthalate about the article followed by quenching the sheath to an amorphous state. The sheathed article is then subjected to vulcanizing conditions in order to convert the sheath from the low density amorphous state to the higher density crystalline state, thus compressing the article to effect a smooth finish.

Utilization of polyester in place of lead for use as a sheathing

A molded extensible-collapsible container having a series of flutes, in the generic sense, in its side to permit the container when subjected to an external force to move to a collapsed position or to the extended position when preferably the yield point of the plastic is no greater than about 5% and it has an ASTM modulus of elasticity greater than about (6.895.times.10.sup.8 pascals) and less than about (2.758.times.10.sup.9 pascals) and preferably about (1.034.times.10.sup.9 pascals to 2.069.times.10.sup.9 pascals). The plastic of the blow molded container can be a blow moldable polyester of less than 5% elongation at yield with polyethylene terephthalate being most preferred.

Growing community of inventors

North Canton, OH, United States of America

Donald E Richeson