摘要

　　　聚乙交酯（PGA）是一種簡單的聚酯，它具有優異的可生物降解性和生物相容性，其最終降解產物為二氧化碳和水，可通過機體正常的新陳代謝排出體外，是一類較重要的醫用高分子材料。

　　　聚乙交酯的經典制備方法主要有兩種：直接縮合聚合法和乙交酯開環聚合法。直接縮合聚合法工序短，操作簡單，原材料試劑消耗少，但一般只能得到相對分子量在幾十至幾千的低聚物，產物性能差，易分解，其力學強度遠不能滿足外科手術縫合線、外科植入材料的使用要求；乙交酯開環聚合法能夠合成高分子量的聚乙交酯，且較少有機雜質對產品的干擾等優點。本論文以高純度的單體乙交酯為原料，采用乙交酯開環聚合的方法合成高分子量的聚乙交酯， 測試了聚合物的特性粘度，并以此參數作為聚合物分子質量的指標 。論文主要考察了催化劑種類及用量、聚合溫度、聚合時間、添加劑的種類和用量等因素對聚乙交酯相對分子量的影響。通過聚合反應條件優化，得到了這些影響因素較佳組合。結果表明，聚乙交酯合成的最佳工藝參數為：乙交酯5.0g，加入0.0015g的催化劑 SnCl2·H2O，聚合反應溫度為180℃，聚合時間為1.5h；追加聚合溫度為160℃，時間為8h。在優化條件下，合成的聚乙交酯的特性粘度為0.435dL/g；在此基礎上加入0.0015g的改性劑月桂醇，0.3g的添加劑丙交酯，聚乙交酯的分子量有一定的提高。

關鍵詞：聚乙交酯；開環聚合；乙交酯；生物降解材料

Abstract

　　　Polyglycolide acid is a kind of simple polyester with excellent biodegradability and biocompatibility．Carbon dioxide and water，as its ultimate degraded products can be excreted from the body via metabolism．

　　　There are two means available for the preparation of PGA，namely，contract-synthesis polymerization and ring-opening polymerization．The former is a simple method with the advantages of short procedure，simple operation，and less reagent consumption．Nevertheless，the molecular weight of the PGA has rise value generally within the scope of 10000 or a 1ittle bit more and the degree of polymerization is very low，which enable it far from perfect to satisfy the practical requirements for sewing in surgical operations and transplantation．The glycolide open legally able to synthesize high molecular weight polyethylene cyclic polymers of lactide，and the less the interference of organic impurities in the product．In this thesis，high-purity monomers glycolide has been used as raw materials，glycolide ring-opening polymerization method of synthesis of  polyglycolide with high molecular weight． Intrinsic viscosity of the polymers are tested and used as the polymer molecular weight indicators．In the study，the factors of catalyst type and amount of the polymerization temperature，polymerization time，the types of additives and the amount of ester relative molecular weight polyethylene cross have been optimized．The results showed that the optimum parameters are as follows：glycolide 5.0g，SnCl2·H2O 0.0015g，reaction temperature of 180℃，polymerization time 1.5h；an additional polymerization temperature of 160℃，reaction time of 8h．Under the optimized conditions，the intrinsic viscosity of the synthesis of polyglycolide is 0.435dL/g．By adding the modifier lauryl of 0.0015g and additive lactide of 0.3g，the molecular weight of polycolide is improved in some extent．

Key words：polyglycolide；ring-opening polymerization；glycolide；biodegradable materials