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:
Aug. 18, 1987
Filed:
May. 16, 1986
Jacobus J Zeilstra, Doetinchem, NL;
Ted Brink, Arnhem, NL;
Akzo nv, Arnhem, NL;
Abstract
A copolyetherester comprising a random head-to-tail copolymer of 25-55 percent by weight of short-chain ester units; at least 75 mole percent is composed of 1,4-butylene terephthalate units, and long-chain ester units derived from ethylene oxide-capped poly(propylene oxide) glycol having an ethylene oxide content of from 15-35 percent by weight and a number average molecular weight ranging from 1500-2800. The copolyetherester displays improved physical properties, such as a higher elongation at rupture, notched tensile impact energy and tearing energy, if its relative viscosity (1 g of polymer in 100 g m-cresol at 25.degree. C.) is in the range of 2,45 to 5,0 and the melt index MFI is between ##EQU1## It may be prepared by melt condensation of a copolyetherester having a relative viscosity of 1,8 to 2,5 and subsequently subjecting it to post-condensation in the solid phase for a sufficient period to obtain a polymer corresponding to said viscosity and melt index.