对聚丙烯T30s接枝交联复合改性制备高熔体强度聚丙烯(HMSPP)进行了研究,分别由正交实验和曲面响应分析可知,BPO对乙烯基长链不饱和硅烷交联改性T30s粒料和粉体制备HMSPP熔体强度的影响最显著;在粒料反应中通过优化实验,得到的HMSPP熔体...对聚丙烯T30s接枝交联复合改性制备高熔体强度聚丙烯(HMSPP)进行了研究,分别由正交实验和曲面响应分析可知,BPO对乙烯基长链不饱和硅烷交联改性T30s粒料和粉体制备HMSPP熔体强度的影响最显著;在粒料反应中通过优化实验,得到的HMSPP熔体强度为19.9 c N;在粉体反应中,通过优化实验,得到的HMSPP熔体强度为21.1 c N。二乙烯基苯(DVB)作为助交联剂可有效提高HMSPP的熔体强度,St对PP链断裂抑制较明显。交联改性中聚丙烯WB130的加入可使改性制得的HMSPP熔体强度显著提高,当WB130加入量为40%时,熔体强度可达34 c N。展开更多
Foamable high melt strength polypropylene (HMSPP) was prepared by grafting styrene (St) onto polypropylene (PP) and simultaneously introducing poly- dimethylsiloxane (PDMS) through a one-step melt extru- sion ...Foamable high melt strength polypropylene (HMSPP) was prepared by grafting styrene (St) onto polypropylene (PP) and simultaneously introducing poly- dimethylsiloxane (PDMS) through a one-step melt extru- sion process. The effect of PDMS viscosity on the foaming behavior of HMSPP was systematically investigated using supercritical CO2 as the foaming agent. The results show that the addition of PDMS has little effect on the grafting reaction of St and HMSPP exhibits enhanced elastic response and obvious strain hardening effect. Though the CO2 solubility of HMSPP with PDMS (PDMS-HMSPP) is lower than that of HMSPP without PDMS, especially for PDMS with low viscosity, the PDMS-HMSPP foams exhibit narrow cell size distribution and high cell density. The fracture morphology of PDMS-HMSPP shows that PDMS with low viscosity disperses more easily and uniformly in HMSPP matrix, leading to form small domains during the extrusion process. These small domains act as bubble nucleation sites and thus may be responsible for the improved foaming performance of HMSPP.展开更多
文摘对聚丙烯T30s接枝交联复合改性制备高熔体强度聚丙烯(HMSPP)进行了研究,分别由正交实验和曲面响应分析可知,BPO对乙烯基长链不饱和硅烷交联改性T30s粒料和粉体制备HMSPP熔体强度的影响最显著;在粒料反应中通过优化实验,得到的HMSPP熔体强度为19.9 c N;在粉体反应中,通过优化实验,得到的HMSPP熔体强度为21.1 c N。二乙烯基苯(DVB)作为助交联剂可有效提高HMSPP的熔体强度,St对PP链断裂抑制较明显。交联改性中聚丙烯WB130的加入可使改性制得的HMSPP熔体强度显著提高,当WB130加入量为40%时,熔体强度可达34 c N。
基金Acknowledgements This work was financially supported by National Natural Science Foundation of China (Grant Nos. 21476085 and 21306047), Fundamental Research Funds for the Central Universities of China (22A201514016 222201314051).
文摘Foamable high melt strength polypropylene (HMSPP) was prepared by grafting styrene (St) onto polypropylene (PP) and simultaneously introducing poly- dimethylsiloxane (PDMS) through a one-step melt extru- sion process. The effect of PDMS viscosity on the foaming behavior of HMSPP was systematically investigated using supercritical CO2 as the foaming agent. The results show that the addition of PDMS has little effect on the grafting reaction of St and HMSPP exhibits enhanced elastic response and obvious strain hardening effect. Though the CO2 solubility of HMSPP with PDMS (PDMS-HMSPP) is lower than that of HMSPP without PDMS, especially for PDMS with low viscosity, the PDMS-HMSPP foams exhibit narrow cell size distribution and high cell density. The fracture morphology of PDMS-HMSPP shows that PDMS with low viscosity disperses more easily and uniformly in HMSPP matrix, leading to form small domains during the extrusion process. These small domains act as bubble nucleation sites and thus may be responsible for the improved foaming performance of HMSPP.