| 摘要 |
<p>An oxidation resistant, microporous polyolefin web exhibiting high-strength mechanical and low electrical resistance properties is a solid matrix that includes an ultrahigh molecular weight polyolefin component and a friable precipitated silica component. The ultrahigh molecular weight polyolefin component provides high-strength mechanical properties to the web. The friab le precipitated silica component is broken down into predominately discrete silica aggregates dispersed throughout the microporous web to maintain a low electrical resistance in the presence of an electrolyte. In an alternative embodiment, a polyethylene web includes an antioxidant coating that is appli ed to the separator web following extraction of the majority of the process oil s and drying of the extraction fluid from the separator pores. The resultant "sheath" of antioxidant protects the mechanical integrity of the polyethylen e separator by suppressing polyethylene degradation.</p> |
