采用同向啮合双螺杆挤出机的不同螺杆组合形式,研究了捏合错列角对双螺杆挤出聚合物共混物表层和内层分散相粒子粒径及其分布的影响。发现螺杆后段采用不同错列角的捏合盘,对于分散相粒子尺寸和分布状态都有明显影响。在塑化区多段式组合的后段采用剪切强、停留时间长的捏合盘(K45°、K60°),可有效地减小分散相粒子尺寸但分布状态不理想;使用K30°的捏合盘时,分散相粒子分布状态最佳;整体两段式螺杆的前段混合段中设置K45°捏合盘,有利于分散相含量较少情况下粒子的尺寸及分布的均匀性的提高。
The effect angles of kneading blocks on the particle size and distribution in bulk and surface of polymer blends were studied. Using kneading blocks with stronger shear and longer residence time reduced particle sizes but in a non-uniform distribution. K30° kneading blocks could improve the distribution. For the screw with two sections, K45° kneading blocks set in the former section were helpful for smaller particle size and more uniform dispersion.