The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 28, 2003
Filed:
Oct. 25, 2001
Barbara Gantillon, Bessemau, FR;
Jean-Luc Lepage, Francheville, FR;
Timothy McKenna, Lyons, FR;
Véronique Pasquet, Lyons, FR;
Roger Spitz, Lyons, FR;
Rhodia Ster S.A., Sao Paulo, BR;
Abstract
The present invention refers to the production of a polyester-type polymer and more particularly to the solid phase condensation of a polyester. The invention presents a process for manufacturing polyester which comprises at least the following steps: a) esterifying of transesterifying a carboxylic diacid or a carboxylic acid diester with a diol, b) prepolymerizing the esterification or transesterification product in liquid phase until an average degree of polymerization between 10 and 50, preferably between 20 and 45, c) preparing a dispersion of the prepolymer in a non-solvent of diol and non-swelling of the prepolymer liquid, the prepolymer being present in the dispersion in the form of solid particles having diameters under 2 mm and crystallized, with a crystalline lamella thickness under 17 nm, d) polymerizing in dispersed solid phase, e) recovering solid particles. The accomplishment of a dispersed solid phase polymerization permits improving the reaction kinetics. To obtain this improvement, the dispersed solid phase polymerization must be effected with a prepolymer having a particular degree of polymerization properties, of solid particle sizes and of crystalline qualities of the solid.