热剪切对聚乙烯/胶粉共混物结构演变及性能的影响

研究了聚乙烯(PE)/胶粉(GTR)共混物中GTR在不同热剪切加工条件下结构形态的演变过程及其对共混物力学性能、流变性能和溶胀行为的影响。结果表明,PE/GTR共混物中GTR受到热剪切作用后,体系中会出现大量几微米的小颗粒,且几微米的小颗粒随温度的升高和加工时间的延长而增多,但即使在220℃下连续剪切25 min,仍有100μm以上的大颗粒存在。随着加工温度的升高和加工时间的延长,共混物的力学性能、流变性能略有下降;而溶胀比随温度的升高先减小后增大,随时间的延长则略有减小。

Influence of thermal shear on structure evolution and properties of polyethylene/ground tire rubber blends

The evolution of structure morphology of polyethylene(PE)/ground tire rubber(GTR) blends at different thermal shear processing conditions and its effects on the mechanical properties,rheological properties and swelling behavior of the blends were studied.The results showed that there would be a lot of small particles(diameter less than a few microns) to form in the PE/GTR blends after thermal shearing,and these particles increased with increasing temperature and prolonging processing time,but there still existed large particles(diameter more than 100 μm) even after the continuous shearing at 220 ℃ for 25 min.As the increase of the processing temperature and time,the mechanical and rheological properties of the blends decreased slightly;the swelling ratio of the blends decreased first and then increased with the increase of the processing temperature,and reduced slightly with the extension of processing time.