摘要 |
Two-component fibers, having surface area of at least 1 m2/g, suited for replacing cellulose fibers in the manufacture of paper and paper-like products comprise a core of olefinic polymer and from 2 to 50% by weight of a sheath of a hydrophilic polymer, and exhibit values of the tenacity higher than 3,000 meters and cohesion higher than 300 meters. They are prepared by extruding a stable emulsion formed by a mixture of a solution of the olefinic polymer with a solution of the hydrophilic polymer in reciprocally immiscible solvents, at a temperature exceeding the boiling temperature of the solvent of the olefinic polymer and at least equal to the dissolution temperature of such polymer in such solvent, in a medium at a lower pressure, by using a volume ratio of solvent for the olefinic polymer to solvent for the hydrophilic polymer of at least 2.5 and concentrations of hydrophilic polymer in its solution of at least 2 g/l of solvent.
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