无水AlCl_3催化PVC/PS反应性增容的研究

STUDY ON REACTIVE COMPATIBILIZATION OF PVC/PS CATALYZED BY ANHYDROUS ALUMINIUM CHLORIDE

以无水AlCl3为催化剂,通过聚氯乙烯(PVC)与聚苯乙烯(PS)之间Friedel-Crafts反应,实现了PVC/PS共混体系的反应性增容,使PVC与PS熔融共混温度由160℃降为140℃;通过预碾磨和加入苯乙烯(St)的方法,提高材料韧性,制备了综合力学性能良好的PVC/PS合金材料.应用FTIR、DSC、SEM和力学性能测试等手段表征了合金材料的结构与性能.结果表明,FTIR出现了1943和838 cm-12个苯环对位被取代的特征吸收峰;DSC在89℃出现了玻璃化转变;SEM证明PVC/PS两相界面粘接性随AlCl3、St的加入越来越好.在PS、AlCl3和St的质量分数分别为6%,0.6%和9%时,实现了对PVC的增强增韧.合金拉伸强度达到60.54MPa,比PVC的49.35 MPa提高了22.7%;缺口冲击强度达到5.3 kJ/m2,比PVC的3.9 kJ/m2提高了35.9%.

The reactive in situ compatibilization of polyvinyl chloride （PVC） and polystyrene （PS） was realized in melt blending through Friedel-Crafts reaction between PVC and PS with anhydrous aluminium chloride as catalyst.The melting temperature of blending PVC and PS decreased from 160℃ to 140℃; Impact toughness of the blends was improved through pre-milling and adding styrene monomer.PVC/PS alloy materials with favorable comprehensive mechanical performance were successfully prepared.The structure and properties of PVC/PS alloy materials were characterized by Fourier transform infrared spectroscopy （FTIR）,differential scanning calorimetry （DSC）,scanning electron microscopy （SEM） and tests of mechanical properties.The results show that the peaks of 1943 cm-1and 838 cm-1 in FTIR spectrum proves the substitution for para-position of benzene,the glass-transition temperature of the blend is 89℃ between 83℃ of PVC and 106℃ of PS.SEM photos show interface adhesion of PVC with PS became better and better with addition of anhydrous alluminium chloride and styrene in proper order.When the mass fraction of PS,anhydrous alluminium chloride and styrene is 6%,0.6% and 9%,strengthening and toughening of PVC were realized,the tensile strength increased from 49.35 MPa to 60.54 MPa,the notched impact strength of the blends material reached 5.3 kJ/m2,compare with 3.9 kJ/m2 of PVC,increased by 35.9%.