| 摘要 |
<p>1434129 Pressing powders E I DU PONT DE NEMOURS & CO 23 May 1973 [14 June 1972] 24645/73 Heading B5A [Also in Division C3] A process for preparing a shaped article from a powder of poly(m-phenylene isophthalamide) (which has been formed into such powder by the method of the invention see Division C3) comprises: (A) subjecting the powder to a forming pressure of at least 10,000 p.s.i. at at most 250‹ C. to form a preform having a density of at least 1À0 g./c.c.; and (B) sintering the preform by heating it without substantial application of pressure to 250‹ to 350‹ C. to provide a shaped article having a density higher than that of the preform and at least 1À24 g./c.c. The powder may be formulated with various filler prior to shaping. Reference is made to Specification 1,309,216.</p> |
