Elucidating enzymatic polymerisations: Chain-length selectivity of Candida antarctica lipase B towards various aliphatic diols and dicarboxylic acid diesters
Elucidating enzymatic polymerisations: Chain-length selectivity of Candida antarctica lipase B towards various aliphatic diols and dicarboxylic acid diesters
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DOI：
10.1016/j.eurpolymj.2018.07.009
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发表时间：
2018-09-01
影响因子：
6
通讯作者：
Farmer, Thomas J.
中科院分区：
文献类型：
--
作者：
Pellis, Alessandro;Comerford, James W.;Farmer, Thomas J.
由于现代社会需要保护环境，同时为子孙后代提供可持续的废旧产品和食品，因此聚合物的可持续合成是一个越来越受关注的领域。在这项工作中，我们研究了在无溶剂反应体系中合成由各种二羧酸二酯和二醇衍生的脂肪族聚酯的可能性。选择南极假丝酵母脂肪酶 B 作为生物催化剂，并阐明其对碳和酯链长度的选择性。所选酶能够合成结合 C-4-C-10 二酯和 C-4-C-8 二醇的各种聚酯。所有组合在 24 小时内单体转化率均超过 90%，通过己二酸二甲酯和 1,8-辛二醇的组合获得最佳数均分子量 (M-n)，导致 M-n 为 7141 Da。差示扫描量热分析显示聚合物熔融温度升高的明显趋势，这与 M-n 或聚合物结构重复单元碳链长度的增加相关。对选定样品进行的热重分析和流变学测量也证实了聚合物降解温度和粘度曲线变化的趋势。
The sustainable synthesis of polymers is a field with growing interest due to the need of modem society to preserve the environment whilst making used products and food sustainable for the future generations. In this work we investigate the possibility of synthesizing aliphatic polyesters derived from various dicarboxylic acid diesters and diols in a solvent-free reaction system. Candida antarctica lipase B was selected as biocatalyst and its selectivity towards the carbon and ester chain length were elucidated. The selected enzyme was able to synthesize various polyesters combining C-4-C-10 diesters and C-4-C-8 diols. All combinations led to monomer conversions above 90% in 24 h with the best number average molecular weights (M-n) being obtained through the combination of dimethyl adipate and 1,8-octanediol leading to a M-n of 7141 Da. Differential scanning calorimetry analysis shows a clear trend with an increase in melting temperature of the polymers that correlates with both the increase of the M-n or of the polymer's constitutional repeat unit carbon chain length. Thermogravimetric analysis and rheology measurements performed on selected samples also confirm the trend showing a variation of the polymer's degradation temperatures and viscosity profiles.