二叔丁基过氧化物对PS/超临界流体CO2挤出发泡的影响

在自行研制的超临界流体CO2挤出发泡实验装置上研究了二叔丁基过氧化物（DTBP）对聚苯乙烯（PS）/超临界流体CO2挤出发泡的影响。结果表明，当DTBP的含量大于0.5 %时，PS的重均相对分子质量急剧下降，发生剧烈降解，使PS的熔体黏度急剧下降。在机头温度为112 ℃，机头压力为4 MPa，DTBP的含量小于0.3 %时，挤塑聚苯乙烯泡沫（XPS）的表观密度下降幅度较大；当其含量大于0.3 %时，下降趋势减缓。DTBP的加入使XPS的弹性模量、压缩强度和弯曲强度增大，弯曲模量降低。

Effect of DTBP on Extrusion Foaming of Polystyrene by Supercritical CO2

Effect of DTBP on the behavior of XPS foaming with supercritical CO2 was studied. It was observed that when the DTBP content was higher than 0.5 ％, the weight average molecular weight of PS decreased sharply, accompanied by a decrease in melt viscosity. When the mold temperature was 112 ℃, the mold pressure was 4 MPa； DTBP content was lower than 0.3 ％, the apparent density of XPS foam decreased remarkably. A higher DTBP content could slow down such decrease. The introduction of DTBP caused modules, compressive and flexural strengths increased, but the flexural modulus decreased.