Fina Technology, Inc.

Joseph M Schardl, Jr

Vincent Henri Barre

Mark Miller

Lu Ann Kelly

Likuo Sun

LuAnn Kelly

Al Baumgartner

Greg Dekunder

James Layne Lumus

Layne Lumus

Kevin Boyle

A processable polypropylene composition comprising a mixture of a major amount of a syndiotactic polypropylene and a minor amount of polyethylene wax. The syndiotactic polypropylene has a designated recrystallization temperature, an original minor melting peak and a higher original melting peak. The polyethylene wax provides a recrystallization temperature of the mixture that is greater than the recrystallization temperature of the syndiotactic polypropylene alone and also provides for a minor melting peak and a major melting peak of the mixture, which has a temperature difference which is lower than the difference between the original minor melting peak and the original major melting peak of the syndiotactic polypropylene alone. A process for the production of polypropylene product employing a polyethylene-syndiotactic polypropylene composition as described which is heated to provide a plastic mass of the syndiotactic polypropylene and polyethylene which is processed to provide the product.

Polyethylene-syndiotactic polypropylene composition and processing thereof

Syndiotactic polypropylene blends having a unique set of mechanical properties may be prepared by blending syndiotactic polypropylene with a high molecular weight mineral oil, an ultra low density polyethylene, or both. The syndiotactic polypropylene blends of the present invention have been found to have reduced flexural modulus, reduced haze, improved impact strength and shorter injection molding cycle times. It has been determined that the addition of about 5 to about 10 percent high molecular weight mineral oil to a syndiotactic polypropylene can decrease flexural modulus values by about 25 to about 30 percent. Moreover, the addition of up to about 10 percent mineral oil to the syndiotactic polypropylene material does not show signs of bleeding or impair clarity, in fact, percent haze values are slightly improved with the addition of mineral oil. Additionally, injection molding cycle time optimization shows an improvement of about 12 seconds in overall cycle time utilizing a syndiotactic polypropylene blend with 5% mineral oil in comparison to a syndiotactic polypropylene without mineral oil. The syndiotactic polypropylene blends according to the present invention may be further processed according to accepted practices to make cast films, blown films, injection molded parts, blow molded containers, and other articles using basic plastics fabrication techniques as known in the art.

Modification of syndiotactic polypropylene with mineral oil

Syndiotactic polypropylene blends having a unique set of mechanical properties may be prepared by blending syndiotactic polypropylene with an ultra low density polyethylene and, optionally, an isotactic polypropylene random copolymer. The syndiotactic polypropylene blends of the present invention have been found to have improved impact strength, reduced haze, increased light transmittance, and reduced flexural modulus. It has been determined that the addition of about 10 to about 50 wt % of an ultra low density polyethylene plastomer to a syndiotactic polypropylene can greatly enhance mechanical toughness, particularly at low temperatures, while maintaining good optical clarity. These results are made possible by using a sPP material with good optical clarity and dispersing the ULDPE plastomer uniformly throughout the sPP matrix to act as a sort of impact modifier. Moreover, the addition of about 10 to about 50 wt % of an iPP random copolymer to the sPP matrix phase provides comparable or improved mechanical properties while also resulting in a significant reduction in injection molding cycle times. The syndiotactic polypropylene blends according to the present invention may be further processed according to accepted practices to make cast films, blown films, co-extruded films, laminated sheets, injection molded parts, blow molded containers, and other articles using basic plastic fabrication techniques as known in the art.

Clear impact-resistant syndiotactic polypropylene

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Cypress, TX, United States of America

Joseph M Schardl, Jr