酯類聚合物因其酯基具有可降解性，因此相對於石化塑膠而言更容易被環境分解，但應用於開環聚合反應的金屬催化劑，可能因為金屬外部缺乏配位基保護修飾，而無法有效控制每條聚合物鏈長，因此設計催化劑結構時，可以透過修飾配位基的立體障礙和電子效應，改善催化劑活性並減少副反應，以獲得狹窄分子量分散性，甚至使用複數金屬時，可利用金屬間協同效應並調節金屬中心特性提升催化效能。基於上述原因，本篇研究參考了過去相關文獻，合成一系列含吡唑配位基之多核鋁錯合物，且產物結晶性高，並在取代基上做了不同的修飾，應用於環己內酯開環聚合反應結果顯示，其皆具有高催化活性及狹窄分子量分布;Polyester is more biodegradable than fossil fuel based plastic because of ester linkages. However, metal catalysts for the cyclic ester ring-opening polymerization infficiently control the length of polymer chains in absence of protecting group on metal center. Ligands can be modified by steric hindrance and electronic effect to improve the catalytic efficiency , prevent side reaction, and obtain narrow polymer dispersity. Moreover, cooperation between multiple metals and adjusting properties of central metal lead growth activity of catalyst. On the basis of above, in spired by related reports, we synthesized a series of multinuclear aluminum complexes bearing pyrazoles and modified their substitute group. The results showed that they are highly active for ring-opening polymerization of ε-caprolactone and yield narrow molecular weight distributions.
