粉末NBR和交联剂在PVC／HDPE中的增容－交联作用

用抽提、示差扫描量热仪、扫描电镜和拉伸试验等方法，研究了粉末丁睛橡胶（Ｐ－ＮＢＲ）与以过氧化二异丙苯、三烯丙基异氰尿酸酯和ＭｇＯ组成的交联体系对ＰＶＣ／ＨＤＰＥ（５０／５０）共混物的增容－交联协同作用。单独加交联剂时主要发生ＨＤＰＥ的自交联，并使共混物形成半互穿网络结构，从而提高其力学性能；如再加入Ｐ－ＮＢＲ，则可明显促进两组分的相互分散，使交联剂聚集在两相的界面，ＰＶＣ和ＨＤＰＥ间产生大量互交联，从而显著提高共混物的力学性能。

COMPATIBILIZATION - CROSSLINKING SYNERGISM OF P - NBR AND CROSSLINKING AGENT ON PVC/HDPE BLEND

The compatibilization - crosslinking synergism of powdered nitrile rubber (P-NBR) and crosslinking agent composed of dicumyl peroxide, triallyl isocyanurate and magnesium oxide on PVC/HDPE (mass ratio 50/50) blend was studied by extraction , differential scanning calorimeter , scanning electronic microscope and tensile test . It was found that PVC was hardly crosslinked when the crosslinking agent was only added , while HDPE was crosslinked and the properties of the blend were improved due to the formation of the semi-interpenetrating polymer networks . When P-NBR was added to the blend together with the crosslinking agent , the phase dispersion of PVC and HDPE was improved at the same time , the crosslinking agent was attracted to the interfacial area . Thus a great number of co-crosslinking products were formed and the mechanical properties were enhanced .