IP Library › Granted Patent US 8,039,581
Granted Patent B2
US 8,039,581 · App. 11/888,255 · Granted Oct 18, 2011

Thermal crystallization of a molten polyester polymer in a fluid

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Quick Facts
Patent No.
US 8,039,581
App. No.
11/888,255
Granted
Oct 18, 2011
Kind
B2
Abstract

A process for crystallizing a polyester polymer by introducing a molten polyester polymer, such as a polyethylene terephthalate polymer, into a liquid medium at a liquid medium temperature greater than the T g of the polyester polymer, such as at a temperature ranging from 100° C. to 190° C., and allowing the molten polyester polymer to reside in the liquid medium for a time sufficient to crystallize the polymer under a pressure equal to or greater than the vapor pressure of the liquid medium. A process flow, underwater cutting process, crystallization in a pipe, and a separator are also described.

Claims (1)

1. A polyester pellet having a degree of crystallization of about 35% or greater induced by heat retained in the pellet from its melt phase.

Assignments (2)
CHANGE OF NAME Recorded Jan 11, 2022
From: GRUPO PETROTEMEX, S.A. DE C.V.
To: ALPEK POLYESTER, S.A. DE C.V.
Reel/Frame 058691/0337 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 1, 2011
From: EASTMAN CHEMICAL COMPANY
To: GRUPO PETROTEMEX, S.A. DE C.V.
Reel/Frame 025727/0963 →