【作者】 吴昊；

【导师】 张昌辉；

【作者基本信息】 陕西科技大学 ， 有机化学， 2013， 硕士

【摘要】 脂肪族聚酯塑料，由于具有较好的生物可降解性能，已逐渐成为世界范围内研发的热点之一。其中，聚丁二酸丁二醇酯（PBS)，由于其具有较高的熔点，较好的加工性能，因此日益成为人们关注的焦点。但是，常规合成方法所得PBS的分子量较低，其加工和应用性能较差；另外，PBS结构对称性高，结晶度高，导致其生物降解速度较慢，达不到人们预期的要求。为了克服以上缺点，本文首先采用了与羟基官能团有较高反应活性的六亚甲基二异氰酸酯（HDI）和己二酰氯对常规法合成的羟基封端的PBS分别进行了扩链研究；然后，选用了N-甲基二乙醇胺对PBS进行了改性研究，并采用己二酰氯对改性产物进行了进一步的扩链研究；最后，对本文合成产物的生物降解性能进行了对比研究。主要研究内容及结果如下：(1)采用HDI和己二酰氯对常规法合成的羟基封端的PBS分别进行了扩链研究，探讨了最佳的合成反应条件。结果表明：①HDI和己二酰氯对PBS扩链后，其扩链产物的分子量均高于扩链前PBS的分子量；②HDI对PBS扩链反应的最佳反应条件和结果为：反应时间为60min，反应温度为140℃，HDI加入量为4%时，扩链产物的分子量最高，其数均分子量从扩链前的7.45万提高到了扩链后的13.8万；③己二酰氯对PBS扩链反应的最佳反应条件和结果为：反应时间为60min，反应温度为135℃，己二酰氯加入量为5%时，扩链产物的分子量最高，其数均分子量从扩链前的7.45万提高到了扩链后的12.84万；热分解温度由扩链前的330℃升高到了扩链后341℃；熔点由扩链前的119℃上升到了扩链后的128℃。断裂伸长率从扩链前391%增加到了扩链后的443%。(2)选用N-甲基二乙醇胺对PBS进行了共聚改性研究，并采用己二酰氯对共聚改性产物进行了进一步的扩链研究。共聚改性研究结果表明：N-甲基二乙醇胺用量增加，其共聚改性产物的分子量和熔点均有下降趋势。N-甲基二乙醇胺加入量为3%时，其分子量由共聚改性前的7.45万，下降到了共聚改性后的6.5万；熔点由共聚改性前的117℃，下降到了共聚改性后的98℃。断裂伸长率从扩链前的391%增加到了改性后的484%。己二酰氯对上述N-甲基二乙醇胺加入量为3%时的共聚改性产物进一步的扩链研究结果表明：①扩链后产物的分子量高于扩链前共聚改性产物的分子量；②在己二酰氯加入量为3%时，产物分子量由扩链前的6.5万提高到了扩链后的11.02万。(3)采用土壤培养液对不同端基PBS的生物降解性能进行了对比研究，对PBS及己二酰氯扩链后PBS的生物降解性能进行了对比研究。其生物降解速度由快到慢的次序为：①羟基封端PBS＞羧基封端PBS＞PBS；②PBS＞己二酰氯扩链后PBS。（4）采用土壤培养液对PBS、N-甲基二乙醇胺改性PBS及己二酰氯扩链后的N-甲基二乙醇胺改性PBS的生物降解性能进行了对比研究。其生物降解速度由快到慢的次序为：N-甲基二乙醇胺改性PBS＞己二酰氯扩链后的N-甲基二乙醇胺改性PBS＞PBS。更多还原

【Abstract】 With better biodegradable properties, aliphatic polyester plastic hasgradually become one of the hot research in the world. Among those,poly(butylene succinate)(PBS), having a higher melting point and better processability, is increasingly becoming the focus of attention. PBS synthesized by theconventional method has a relatively low molecular weight and poor processingand application performance. In addition, its higher PBS structural symmetry andhigh crystallinity result in a slower biodegradation rate, which can not meet theexpected requirements.In order to overcome the above disadvantages, in this paper, PBS ended byhydroxyl was first synthesized by conventional methods. And chain extenderreaction on PBS was researched by higher reaction activity of hexamethylenediisocyanate (HDI) and adipoyl chloride against hydroxyl functional groups.Then, modification of PBS was also studied by N-methyl-diethanolamine, andthe chain extender reaction of the modified product was further studied byadipoyl chloride. Finally, the biodegradability of synthetic products wasconsidered comparatively.The main content and the results are as follows:(1) Chain extender reaction on PBS was researched by higher reactionactivity of hexamethylene diisocyanate (HDI) and adipoyl chloride againsthydroxyl functional groups. The results show that after chain-extended by HDIand adipoyl chloride, the molecular weight of the product is higher than PBS’s.The optimum reaction conditions and results of chain extension on PBS by HDIwere reaction time was60min; the reaction temperature was140℃; the amountof the added HDI was4%. After the chain extension reaction, the highestmolecular weight of the product increased from7.45×104to1.38×105. Theoptimum reaction conditions and results of chain extension on PBS by adipoylchloride were reaction time was60min; the reaction temperature was135℃; theamount of the added adipoyl chloride was5%. After the chain extension reaction,the molecular weight of the product increased from7.45×104to1.284×105; the thermal decomposition temperature increased increased from330℃to341℃;melting point increased from119℃up to128℃; elongation at break raised from391%to443%; thermal decomposition temperature added from330℃to341℃.(2) Modification of PBS was also studied by N-methyl-diethanolamine, andthe chain extender reaction of the modified product was further studied byadipoyl chloride.Results of research on copolymerization modification show that With theincreasing of N-methyl-diethanolamine concentration, the molecular weight andthe melting point of the modified product showed a decreasing trend. When theamount of the added N-methyl-di-ethanolamine is3%, the molecular weightdecreased from7.45×104to6.5×104; melting point descend from119℃to128℃;elongation at break raised from391%to484%.The results of further chain extension reaction on the above products byadipoyl chloride show that after the chain extension reaction, the molecularweight of the product was higher than the product before copolymerizationmodification; when adipoyl chloride was added in an amount of3%, themolecular weight of the polymer increased from6.5×104to11.02×104.(3)The biodegradability in soil culture medium on PBS, PBS with differentend groups and PBS chain-extended by adipoyl chloride was studiedcomparatively. The order of biodegradable speed from fast to slow was PBSterminated by hydroxy> PBS capped carboxy> PBS; PBS> PBSchain-extended by adipoyl chloride.The biodegradability in soil culture fluid on PBS, PBS modified byN-methyl-diethanolamine, and modified PBS by N-methyl diethanolamine afterchain-extended by adipoyl chloride was researched comparatively. The order ofbiodegradable speed from fast to slow was PBS modified byN-methyl-diethanolamine> PBS modified by N-methyl diethanolamine afterchain-extended by adipoyl chloride> PBS.更多还原