稀土β成核剂对高抗冲聚丙烯性能的影响

Effects of Rare Earth β Nucleating Agent on Properties of High-Impact Polypropylene

通过力学性能测定、示差扫描量热和广角X射线衍射等方法,考察了稀土β成核剂(W BG)对高抗冲聚丙烯(H IPP)力学性能和结晶行为的影响。实验结果表明,加入W BG可使H IPP的冲击强度、断裂伸长率和热变形温度大幅度提高。当W BG添加量(质量分数)为0.15%时,试样中β晶的相对含量达到90%以上。结晶动力学研究表明,加入W BG导致H IPP体系在非等温结晶条件下结晶速率减慢,但W BG具有明显的异相成核作用,当W BG添加量为0.10%时,可使初始结晶温度升高10℃以上。含W BG的H IPP体系经多次加热-冷却处理后β晶的相对含量未发生显著变化,说明W BG具有良好的加工稳定性。

Effect of rare earth fl nucleating agent（WBG） on mechanical properties and crystallization behavior of high - impact polypropylene （HIPP） was investigated by means of DSC and WAXD. WBG is an effective β - form nucleating agent in transition of HIPP crystalline form from α to β - form. When addition of WBG is 0.15% （mass fraction）, relative content of β- form in the sample reaches more than 90%. Addition of WBG remarkably increases impact strength, elongation at break, rupture strength and heat distortion temperature of HIPP, but slightly decreases its elastic modulus and yield strength. Concerning non - isothermal crystallization behavior of HIPP, addition of 0. 10% （mass fraction ） WBG decreases crystallization rate slightly but increases initial crystallization temperature for more than 10 ℃, which shows effect of WBG in nucleation. When HIPP with WBG after experiencing multi heating - cooling cycles in processing, no obvious change of WBG content was observed, which indicated good processing stability of WBG.