04876326 is referenced by 17 patents and cites 4 patents.

High molecular weight polyester resins such as polyethylene terephthalate, are sometimes produced from low molecular weight polyester prepolymers having the same composition by solid state polymerization. The low molecular weight polyester prepolymers which are used in such solid state polymerizations are normally prepared by conventional melt polymerizations and are generally in the form of pellets or chips. It has been unexpectedly found that solid state polymerization rates can be greatly improved by utilizing polyester prepolymers which are in the form of porous pills. By utilizing polyester prepolymers that are in the form of porous pills, higher molecular weights can be achieved after shorter solid state polymerization times.

Title
Solid state polymerization of polyester prepolymers
Application Number
30319
Publication Number
4876326
Application Date
March 11, 1988
Publication Date
October 24, 1989
Inventor
Verne R Rinehart
McArthur
OH, US
Agent
Alvin T Rockhill
Assignee
The Goodyear Tire & Rubber Company
OH, US
IPC
C08G 63/02
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