| US 7,468,405 B2 | ||
| Increase in the melting point and the enthalpy of melting of polyamides by a water treatment | ||
| Jean-Philippe Allen, Irigny (France); Philippe Blondel, Bernay (France); and Patrick Douais, Le Noyer en Ouche (France) | ||
| Assigned to Atofina, Puteaux (France) | ||
| Filed on Oct. 22, 2003, as Appl. No. 10/689,840. | ||
| Claims priority of provisional application 60/425319, filed on Nov. 12, 2002. | ||
| Claims priority of application No. 02 13219 (FR), filed on Oct. 23, 2002. | ||
| Prior Publication US 2004/0138344 A1, Jul. 15, 2004 | ||
| Int. Cl. C08F 6/24 (2006.01); C08F 6/00 (2006.01); C08J 3/28 (2006.01) | ||
| U.S. Cl. 523—328 [528/499; 528/503] | 8 Claims |
| 1. A method for increasing at least one of the following two parameters of a polyamide: (i) melting point and (ii) enthalpy
of melting ΔHm, comprising:
contacting solid granular or powdered polyamide with a substance consisting of water, water containing methanol, or steam,
at a temperature close to crystallization temperature Tc of the polyamide, for a time long enough to effect said increase;
separating water or steam from the polyamide and drying the polyamide.
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