| 摘要 |
<p>Polycarbonate pellets characterized in that (a) the median particle size of said pellets is between 250 and 1,000 microns; (b) the particle size dispersion of said pellets is less than 100 microns; and (c) the skew of the particle distribution is less than 0.25; each as determined according to ASTM Designation D 1921-63. These pellets are further characterized in that, (a) when said polycarbonate pellets are agitated on a screen having a mesh opening size of 850 microns, and when those pellets not retained on said 850 micron screen are then agitated on a screen having a mesh opening size of 710 microns, the portion of said pellets which together is retained on one or the other of said screens is more than 85 percent by weight; and (b) none of said pellets are retained when agitated on a mesh screen having a mesh opening size of 1,500 microns or more. These pellets are prepared by cutting molten polycarbonate as it is emitted from a die, preferably cutting the polycarbonate at the face of the die. Polycarbonate pellets thus characterized are easier to handle and process than those which have a larger median size, size dispersion and/or skew distribution.</p> |
