Kanebo, Limited

Research Association for Synthetic Fiber Technology

Toshihiro Kushimoto

Yoshimichi Ozawa

Koei Igarashi

Michiaki Fuji

Kenji Yao

Nobuo Izawa

Polyester containing 9,9-bis(4-(2-hydroxyalkoxy)phenyl fluorene

A process for producing a linear polyester comprising a main structural unit of an aromatic dicarboxylic acid ester of an alkylene glycol, particularly, comprising a polyethylene terephthalate or polytetramethylene terephthalate unit, is provided. In the process of the invention, the polycondensation reaction is conducted in the presence of a niobic acid catalyst that is obtained by heat-treating a hydrated niobium compound at the temperature range between 80.degree. C. and 400.degree. C. The process of the invention is also effecitvely applied to the manufacture of an elastomeric polyester comprising a polyalkylene terephthalate as a hard segment and a polyalkylene glycol as a soft segment.

Process for producing polyesters using a niobium compound as a catalyst

Growing community of inventors

Osaka, Japan

Toshihiro Kushimoto