【作者】 肖祥雄；

【导师】 张兴华；

【作者基本信息】 广东工业大学 ， 材料学， 2007， 硕士

【摘要】 聚丙烯（PP）是五大通用塑料之一，其有用途广泛、产量大、价格低廉、耐水、耐化学腐蚀、以及容易成型等优点。但是聚丙烯具有非极性和结晶性，使其与其它极性聚合物、无机填料及增强材料等材料的相容性差，共混或者复合时需要加入增容剂来降低界面的张力，从而增加界面的粘接强度；另外其染色、粘接性能、抗静电性能、亲水性能也很差，这些缺点严重制约了聚丙烯的进一步推广应用。马来酸酐（MAH）是一种含有多种官能团的极性化合物。分子结构中含有不饱和双键，容易与其它聚合物发生接枝聚合反应，活性很强的酸酐基团容易与羟基、羧基、胺基等官能团发生化学反应，所以通过用马来酸酐功能化一些极性的聚合物，可以增加其与其它极性物质的相容性。本文研究了以过硫酸铵（APS）为引发剂，通过水相异相法在聚丙烯（粉料）分子链上接枝马来酸酐单体，得到接枝产物（PP-g-MAH），从而使PP功能化。研究的主要内容包括以下三部分：第一部分是对接枝合成体系的研究，用化学滴定法测定产物的接枝率。考察了单体用量、引发剂用量、反应温度及反应时间对接枝反应的影响。在此基础上，进一步探讨了怎样提高MAH的利用率，结果表明：1．各种因素对接枝反应都存在着一定的影响，在合适的条件下，可以得到接枝率高达1.10％的产物。2．在同样的条件下，对反应体系中的马来酸酐循环利用5次，可以使它的利用率提高至3倍之多。第二部分是主要对在实验室制备的接枝产物进行结构表征和有关性能的测试，可以得出以下结论：1．对纯化的产物进行红外光谱表征，在1700～1900cm^-1出现了新的特征吸收峰，说明了MAH已经接枝到聚丙烯的分子链上。2．极性的MAH单体接枝到PP分子链上后，与纯PP相比较，接枝产物的熔体流动速率下降，熔体的粘度增大，熔点上升，力学性能稍有所提高，与铝片的粘接性能也提升。第三部分主要对接枝产物在PP／PA6共混体系中的应用作了研究。按照一定的配方，共混、制样和测试，发现：1．在体系中加入PP-g-MAH作为增容剂后，共混物之间的相容性大大改善，与未加增容剂的体系对比，各项力学性能均有显著地提高。2．对于一定的共混体系，PP-g-MAH的加入量不是越多越好，而是有一个适当的范围。3．并通过扫描电子显微镜对试样断面进行形貌表征，添加适量PP-g-MAH后，体系的相容效果明显改善，也验证了以上的结论。4．加入适量的PP-g-MAH后，体系中的PP和PA6可以产生共结晶，体系的加工性能也明显改善。更多还原

【Abstract】 Polypropylene (PP) is one of five general purpose plastics and its application field isvery wide. PP has many merits such as lower price, big volume of production, water andchemicals resistance and simple technological process. However it is a nonpolar andcrystalline polymer, so it is difficult to blend it with other polymers, fillers and reinforcingmaterials because of poor interfacial adhesion. So it is hard to develop the novel polymeralloys.Maleic anhydride (MAH) is a polar ramification with many functional groups. Itsstructure and unsaturated double bond make it easy to react and connect with otherpolymers. The active anhydride groups react with hydroxy, carboxy and amimo groupseasily, so as to improve the interphase adhesion and compatibility of the two polymers.In this paper, the heterogeneous grafting of MAH onto PP powder was initiated byammonium persulfate (APS) in water solution. The functionalization of PP isaccomplished by this method.First, the MAH-g-PP was prepared through the heterogeneous grafting reaction. Thegrafting rate was determined by titration. The effects of the concentration of MAH andASP at the beginning of the reaction, and reaction temperature and time on the graftingreaction were investigated. Furthermore, the attempt of promotion of higher efficiency ofMAH was conducted. The result is shown as follow:1. The grafting degree of over 1.10% could be achieved under certain condition in theexperiment.2.The efficiency of original MAH was increased to as high as 3 times by circularlyusing of MAH solution.Second, characterization and property test of the reaction product gave the followingconclusions:1. The IR spectra showed that MAH was successfully grafted onto PP backbone forsome new distinct absorption peaks.2. The melting flow rate of the PP-g-MAH was decreased and the mechanical properties was improved due to the intermolecular action of PP-g-MAH wasenhanced by the polar groups grafted onto PP chain. And the peel strength betweenthe aluminum sheets was improved obviously.And third, the application of PP-g-MAH product as an interfacial improver in theblend of PP/PA6 alloy was experimentally studied. The result is as following:1.PP-g-MAH could perform well in the PP/PA6 composites as the interfacialcompatibilizer. The mechanical properties of the alloy had been improved obviously.2.The level of the PP-g-MAH in the composites should be optimized for specialcomposites.3. The previous conclusions were supported by the SEM analysis of the fracturesurface.4. Cocrystallization can take place in PP/PA6 blends for adding PP-g-MAH, and itsprocess property has improved too.更多还原