| 摘要 |
PURPOSE:To prepare a pulp-like material having excellent dispersibility in a liquid, and composed of fibrous particles having high strength, elongation and elastic modulus, by stirring a dilute solution of a high-molecular weight polyolefin under specific condition and under shearing force, cooling the mixture to a specific temperature, and disintegrating the phase-separated solution. CONSTITUTION:A solution of a polyolefin having a weight-average molecular weight of >=400,000 and a concentration of <=5% is stirred for >=5sec at a temperature above the phase-separation temperature of the solvent and below the phase-separation temperature +50 deg.C, applying a shearing force corresponding to the maximum shear rate of 1-50,000sec<-1> at the outermost edge of the stirring blade. After stirring, the solution is cooled at a rate of >=0.1 deg.C/min to a temperature lower than the phase-separation temperature by >=25 deg.C. The phase-separated solution is disintegrated by the use of preferably a solvent such as water, alcohol, ketone, etc.
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