纳米SiO_2对高抗冲聚丙烯树脂相结构与性能的影响

提出一种使高抗冲聚丙烯树脂的韧性和刚性同时得到提高的新方法.以亲油性纳米SiO_2改性高抗冲聚丙烯树脂,发现少量纳米SiO_2可显著降低高抗冲聚丙烯树脂中乙丙橡胶相的粒径和聚丙烯相的球晶尺寸,进而使高抗冲聚丙烯的常温韧性、低温韧性、刚性和耐热性同时得到提高.研究还发现,结晶成核剂和纳米SiO_2有协同效应,可使高抗冲聚丙烯的综合性能进一步得到提高.

Effect of Nano SiO2 on Phase Structure and Properties of Impact Polypropylene Copolymer Resin

A new method is reported in this paper that the toughness,stiffness and heat resistance of impact polypropylene copolymer (IPC) resin could be increased simultaneously by adding a small amount of hydrophobic nano-SiO2.According to the results of scanning electron microscopy (SEM) and polarized optical microscopy (POM),a small amount of nano-SiO2 can significantly reduce both the particle size of ethylene-propylene rubber and the spherulite size of polypropylene matrix in IPC;therefore,the stiffness,the heat resistance and the toughness of IPC at room temperature and low temperature can be improved simultaneously.Energy dispersive spectroscopy (EDS) results of the composite material indicate that the nano-SiO2 particles are distributed uniformly in IPC resin.Tested in accordance with ASTM standard,the new composite material prepared in this new way shows that the flexural modulus and heat distortion temperature of IPC/nano-SiO2 composite can gain a monotonical increase as much as 8％ and 9.6％.It is also found that the nano-SiO2 and the nucleating agent have synergy effect on IPC modification.When the content of nanoparticles reaches 0.7％,the impact strength gets an increase of 16.5％,the best performance among all samples.The particle sizes of ethylene-propylene rubber and spherulite size ofpolypropylene matrix in IPC are further reduced when nano-SiO2 and nucleating agent are added into IPC together,which improve further the properties of IPC.The flexural modulus,flexural strength,Izod notched impact strength and heat distortion temperature of IPC are increased by 18％,15％,10％ and 20％ when 0.7％ of SiO2 and 0.3％ of nucleating agent VP-101B are added into IPC resin.The experimental results show that,to modify IPC,use of the nano-particles and the nucleating agent together is a promising method to produce high performance IPC with high toughness,high stiffness and high heat resistance.