公开(公告)号：US4490431A

公开(公告)日：1984-12-25

申请号：US438823

申请日：1982-11-03

Applicant: Gunter H. Vitzthum ,  Michael A. Davis

Inventor： Gunter H. Vitzthum ,  Michael A. Davis

IPC: B01D67/00 ,  B01D69/02 ,  B01D71/26 ,  C08J9/00 ,  C08J9/28 ,  B32B3/00 ,  B29D27/04

CPC classification number: C08J9/28 ,  B01D67/003 ,  B01D69/02 ,  B01D71/26 ,  C08J2201/03 ,  C08J2201/052 ,  C08J2201/0542 ,  C08J2323/12 ,  Y10T428/249979

Abstract: There is disclosed a substantially skinless microporous polypropylene membrane characterized by having(a) a bubble point of about 25 to about 50 psi;(b) a thickness of about 3 to about 7 mils;(c) a nitrogen flow rate of at least 0.5 liters per square centimeter-minute;(d) a burst strength of at least 10 psi; and(e) an S value of about 15, or less.There is also disclosed a method of preparing a microporous polypropylene membrane comprising heating a mixture of about 30 percent polypropylene and about 70 percent, N,N-bis(2-hydroxyethyl)tallowamine, by weight, to a temperature and for a time sufficient to form a homogeneous solution, casting or extruding said solution at a thickness of about 3 to about 7 mils, onto a chill roll maintained at a temperature of from about 50.degree. to about 80.degree. C., allowing said solution to solidify on said chill roll to form a solid sheet, removing said solid sheet from said chill roll and removing at least a substantial portion of the liquid from said sheet to form the microporous polypropylene membrane.

Abstract translation: 公开了一种基本上无皮的微孔聚丙烯膜，其特征在于具有（a）约25至约50psi的起泡点; （b）约3至约7密耳的厚度; （c）至少0.5升/平方厘米分钟的氮气流量; （d）至少10psi的爆裂强度; 和（e）约15或更小的S值。 还公开了一种制备微孔聚丙烯膜的方法，其包括将约30％聚丙烯和约70％重量的N，N-双（2-羟乙基）牛油胺的混合物加热到足以使 形成均匀的溶液，将所述溶液以约3至约7密耳的厚度浇铸或挤出到保持在约50℃至约80℃温度的冷却辊上，使所述溶液在所述冷却辊上固化 以形成固体片材，从所述冷却辊中除去所述固体片材并从所述片材中除去至少大部分的液体以形成微孔聚丙烯膜。