发明名称 |
Method for preparing microporous polyolefin shaped articles |
摘要 |
A method for preparing a microporous polyolefin shaped article which includes the steps of (1) melt blending a polyolefin with an additive which is miscible with the polymer at the melt temperature of the blend but which phase separates on cooling to form a solution; (2) forming a shaped article from the solution; (3) cooling the shaped article by use of a patterned chill roll to provide areas on the surface of the article where the polymer mixture does not contact the chill roll; and (4) (a) removing at least a substantial portion of the compatible liquid; or (b) stretching the article in at least one direction sufficient to permanently attenuate the article and effect orientation of the polymer; or (c) a combination of (a) and (b) to form a microporous polyolefin shaped article. The article is of substantially uniform thickness and has a patterned surface. The patterned surface provides substantially skinless areas having high microporosity and skinned areas or reduced porosity.
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申请公布号 |
US5238623(A) |
申请公布日期 |
1993.08.24 |
申请号 |
US19920840291 |
申请日期 |
1992.02.24 |
申请人 |
MINNESOTA MINING AND MANUFACTURING COMPANY |
发明人 |
MROZINSKI, JAMES S. |
分类号 |
B29C35/16;B29C47/88;B29C55/00;B29D7/01;C08J9/28 |
主分类号 |
B29C35/16 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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