| 摘要 |
PROBLEM TO BE SOLVED: To provide processes of heat treatment of polymorphic semicrystalline polymers to provide more uniform melting, improve powder flowability and lower the attrition rates in applications that require powder handling at elevated temperatures and the polymer powders produced by the heat treatment processes.SOLUTION: The invention relates to heat treatment of polymorphic semicrystalline or crystallizable polymers to increase the content of the highest melting crystalline form. Such heat treatment results in a polymer powder that has a consistent, uniform melting range, improved powder flowability and improved powder particle size durability for applications that require powder flowability at elevated temperatures. In addition to the improved powder properties, articles produced from the powders also exhibit excellent physical properties in both appearance and in mechanical properties. Thus the invention also includes polymer powders and articles produced by the described processes.SELECTED DRAWING: None |
