醋酸活化改性滑石粉对PP结构与性能影响

Effect of Acetic Acid Actively Modified Talcum Powder on Structure and Performance of Polypropylene

以醋酸为预处理剂对滑石粉表面进行预处理,再用钛酸酯偶联剂处理得到改性滑石粉,探究醋酸浓度对滑石粉表面性质的影响;将改性滑石粉与聚丙烯(PP)共混制备PP/改性滑石粉复合材料。考察改性滑石粉对复合材料力学性能、尺寸稳定性能和微观结构的影响,并对复合材料的结晶行为进行了分析。结果表明:当醋酸pH值为4.0~5.0时,改性后的滑石粉接触角由73.82°增大到114.97°,活化率达到最大值(93.4%);与未预处理的PP/改性滑石粉复合材料相比,醋酸预处理的PP/改性滑石粉复合材料的冲击性能和拉伸性能均得到较大改善,尺寸变化率减小,稳定性提高,界面结合作用强;醋酸预处理改性滑石粉对PP的结晶行为有影响,结晶温度降低,结晶度下降。

The surface of talcum powder is pretreated with acetic acid as a pretreat- ment agent. Then modified talcum powder were prepared by titanate coupling agent. PP/ modified talcum powder composites were prepared by blending modified talcum powder and PP. The effect of modified talcum powder on mechanical properties, dimensional stability and microstructure of the composites were studied,and the crystallization behaviors of the comoposites were analyzed. The results show that when the pH value of acetic acid is 4.0-5.0,contact angle of modifed talcum power increases from 73.82°to 114.97°, and acti- vation rate reaches the maximum （93. 4%）. Compared with those of the untreated PP/ modified talcum powder composites,the impact and tensile properties of the composites of PP/modifed talcum powder pretreated by acetic acid are greatly improved. Dimension of the composites changes little and the stability improves. Interfacial bonding strength increases. The modified talcum powder pretreated by acetic acid has some effect on the crystallization behavior of PP,and the crystallization temperature and crystallinity decrease.