SETT ATT FRAMSTELLA EN VATTENDISPERSION AV POLYOLEFINFIBRER

摘要

1398623 Paper comprising polyolefin fibres CROWN ZELLERBACH INTERNATIONAL INC 1 Aug 1972 [2 Aug 1971] 35936/72 Heading D2B [Also in Division C3] Paper-like products are obtained by forming a web of polyolefin fibres from an aqueous slurry thereof and drying the web, the aqueous slurry of polyolefin fibres being prepared from a mass of polyolefin fibres in an organic liquid by heating the mass combined with water and in the presence of polyvinyl alcohol, to vaporise and remove the organic liquid from the fibres. The polyolefin fibres may be of polyethylene or polypropylene, obtained by polymerisation in a hydrocarbon or halogenated hydrocarbon which is a solvent for the monomer and which swells the polymer. The resulting fibrous gel may be passed through a disc refiner and non-sorbed solvent separated by centrifuging or filtering. Loss of fibre surface area on solvent evaporation may be reduced by adding to the water a surface active agent having an HLB of at least 10, preferably a non-ionic surface active agent. The resulting slurry may be dewatered and redispersed in water before use in paper making. In examples hand sheets are made from aqueous slurries obtained by mixing masses of polyethylene fibres in hexane with aqueous polyvinyl alcohol solution and heating to drive off the hexane.