微硅粉改性聚丙烯纤维的制备与性能研究

Preparation and properties of polypropylene fibers modified with microsilica

将微硅粉与聚丙烯(PP)按质量比25∶75进行混合,在190℃温度下熔融挤出造粒,制得母粒,再将母粒按微硅粉质量分数为0~25%与PP配成微硅粉/PP共混物,在共混物中加入质量分数5%马来酸酐接枝PP(PP-g-MA),通过熔融纺丝制备初生纤维,初生纤维经拉伸、热定型制得微硅粉改性PP纤维,研究了微硅粉/PP共混物的流变性能和改性PP纤维的结构与性能。结果表明:微硅粉/PP共混物为非牛顿流体,低含量的微硅粉可以降低PP树脂的黏度,提升PP加工流动性;PP-g-MA的加入增强了微硅粉和PP的相容性,微硅粉质量分数小于20%时,微硅粉能均匀分散到PP中;微硅粉的加入,降低了微硅粉改性PP纤维的接触角,但使其力学性能有所降低;当添加微硅粉质量分数为15%时,微硅粉改性PP纤维的接触角为81.99°,断裂强度为4.60 cN/dtex,断裂伸长率为32.78%。

A masterbatch was produced by blending microsilica and polypropylene （PP） at the mass ratio of 25 ： 75 at 190 ℃ through melt extrusion pelletization. A microsilica/pelypropylene （PP） blend was prepared by blending the masterbatch and PP at the microsilica content of 0 -25% by mass fraction, which was produced into an as-spun fiber by adding maleic anhydride- grafted PP （PP-g-MA） at the mass fraction of 5% via melt spinning process. And a microsilica-modified PP fiber was obtained from the as-spun fiber after drawing and heat setting processes. The rheological behavior of the microsilica/PP blend and the structure and properties of the modified PP fiber were studied. The results showed that the microsilica/PP blend was a non-New- tonian fluid; a small amount of microsilica could decrease the viscosity of PP resin and increase its processing flowability ; the ad- dition of PP-g-MA could improve the compatibility of microsilica and PP, and the microsilica could uniformly disperse into PP as the mass fraction of microsilica was below 20% ; the addition of microsilica could decrease the contact angle and the mechanical properties of microsilica-modified PP fiber as well ; and the microsilica-modified PP fiber had the contact angle of 81.99°, break- ing strength 4.60 cN/dtex and elongation at break 32.78% as the mass fraction of microsilica was 15%.