MANUFACTURE OF FIBRIDS OF POLYOLEFINS

Discrete fibrids of polyethylene having lengths of 1 to 50 mm and thicknesses between 2 and 30 .mu.m, are produced by (a) dissolving in a pressure vessel polyethylene, obtained by lowpressure polymerization of ethylene, in a solvent which is a mixture of pentanes and a naphtha cut boiling at 25 to 140.degree.C. and containing pentanes in an amount of from 5 to 50% by weight, the pentanes being selected from the group consisting of n-pentane, isopentane, cyclopentane and neopentane; (b) maintaining the vapor pressure in the pressure vessel at 4 to 60 atmospheres and maintaining the temperature of the polyethylene solution in the pressure vessel at temperature of 80 to 250.degree.C and above the boiling point of the solvent at standard pressure; (c) passing the polyethylene solution from the pressure vessel through an orifice into a space maintained at lower temperature and pressure than those in the pressure vessel; (d) flashing off the solvent in the space from the solution passed through the orifice to produce a tangled mass of polyethylene fibrids, the amount of pentanes in the solvent further being sufficient to cause the polyethylene to separate in form of discrete fibrids upon the flashing off of the solvent in the space; and (e) drying the resultant polyethylene fibrids. The fibrids directly obtained may be used, for example, for the manufacture of paper or for the manufacture of textile-like webs.