Synthetic wood-pulp separators,

Synthetic wood-pulp separators (SWP). So-called synthetic wood-pulp (SWP) separators are used widely in Japan for automotive batteries. These are fleeces made from fibrillated polyethylene or polypropylene and small amounts of additional fibres (e.g., polyester fibres) sometimes, the fleeces are also filled with silica. The organic sheets are laminated with a glass mat, which serves to stabilize the positive active-material [39]. 

Mention may also be made of an application in which careful control of polymer morphology has led to the production of novel materials. By treatment of solutions of high-density polyethylene, products are obtained with a celluloselike morphology and which are known as, fibrides or synthetic wood pulp. They are used for finishing paper and special boards to impart such features as sealability and improved wet strength. They are also reported to be used for such diverse applications as tile adhesives, thixotropic agents, battery separators and teabags ... 

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