無官能基之聚丙烯/聚苯乙烯的反應增容聚摻研究

Abstract

PP和PS是不相容的兩種高分子材料（polymers），利用雙螺桿押出機（twin screw extruder）互相混摻後，從聚摻合物系統之形態學（morphology）所得相分離相當的顯著。本篇論文研究是利用PP-g-MA和SMA兩種不同增容前趨物（compatibilizer precursors）以物理熔融的方式分別官能基化PP和PS，並以TGDDM或DDM作為PP-g-MA和SMA的偶合劑，形成PP-co-PS的增容共聚物（copolymers），並互相比較TGDDM或DDM這兩種偶合劑所形成PP-co-PS的增容共聚物在不相容PP/PS聚摻合系統上的功效。PP/PS與增容前趨物反應押出摻混的結果，有機會形成PP-co-PS的增容共聚物，以in-situ形式位於PP/PS兩相間的界面。PP/PS反應增容聚摻中偶合劑添加量的多寡，明顯的影響相分散區域的大小（domain size），並且擁有較為升高的分子量和機械性質的增加。但是由於PP-g-MA和SMA上連接馬來酐（maleic anhydrides）官能基的結構有所不同，而與TGDDM環氧基（epoxy）或者DDM的氨基（amine）可能產生競爭反應，尤其在DDM氨基上更為顯著，結果反而對上述機械性質的增加造成限制，甚至損害減少其作為增容劑的功效。此次研究證明五種組成的高分子增容反應聚摻系統，亦能夠有效的提昇其各種機械性質，進而提供一種新穎的聚摻方法。

Polypropylene (PP) and polystyrene (PS) are immiscible and have evident scatters from the morphological viewpoint after mixing by twin screw extruder. In this paper, two compatibilizer precursors of maleated polypropylene (PP-g-MA) and styrene maleic anhydride random copolymer (SMA) function the PP and PS respectively by physical melting process. The PP-g-MA and SMA connected by the coupling agents of TGDDM or DDM are formed compatibilizer copolymers of PP-co-PS, and these coupling agents are compared with each other of the effect in this blending system. The reactive extruder results that PP-co-PS are formed as in-situ compatibilizer loading at the interface of PP/PS blends. The effect of reactive compatibilization blends depending on the amount of coupling agent results in smaller phase domain, higher molecular weight and improves mechanical properties significantly. Due to the difference of structure between these two compatibilizer precursors of PP-g-MA and SMA, they are competed to react with TGDDM or DDM, and this situation especially occurs in DDM. We can find that the above condition will degrade the mechanical properties and reduce the effectiveness of compatibilizers. This investigating demonstrates that the five component reactive compatibilization of PP/PS blends can enhance the mechanical properties significantly. And these methods provide a new concept of reactive compatibilization blends in industrial mass processing.