Rodney R L, Stagno J L, Beckman E J, Russell A J
Department of Chemical and Petroleum Engineering & Center for Biotechnology and Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
Biotechnol Bioeng. 1999 Feb 5;62(3):259-66. doi: 10.1002/(sici)1097-0290(19990205)62:3<259::aid-bit2>3.0.co;2-i.
Diphenyl carbonate is an attractive monomer for copolymerization with Bisphenol-A to produce the strong, high melting polycarbonate, Bisphenol-A Polycarbonate. Diphenyl carbonate is an ideal candidate for this polymerization as the phenols constitute good leaving groups during polymerization. Industrially, diphenyl carbonate is produced via the phosgenation of a phenolic sodium salt. Using phosgene creates additional safety hazards as well as concerns in treating or disposing of the reaction by-products. The enzymatic synthesis of diphenyl carbonate via alcoholysis of dimethyl carbonate by phenol is presented. While the process is environmentally benign and eliminates the considerable safety issues related to the use of phosgene, phenol is a poor nucleophile and conversion to diphenyl carbonate is limited. Enzyme catalyzed condensation polymerization of carbonate monomers and diols is a more feasible and direct enzymatic route to polycarbonate. We describe an AA-BB condensation polymerization to make polycarbonates using enzymes at ambient conditions. Molecular weights of up to 8, 500 MW are achieved. Unlike the industrial polymerization, this process is performed without the use of acid catalysts, significant energy input, or high temperature or pressure.
碳酸二苯酯是一种极具吸引力的单体，可与双酚A共聚以生产强度高、熔点高的聚碳酸酯——双酚A聚碳酸酯。碳酸二苯酯是这种聚合反应的理想候选物，因为在聚合过程中酚类构成良好的离去基团。在工业上，碳酸二苯酯是通过酚钠盐的光气化反应制备的。使用光气会带来额外的安全隐患，以及在处理或处置反应副产物时的问题。本文介绍了通过苯酚与碳酸二甲酯醇解反应酶促合成碳酸二苯酯的方法。虽然该过程对环境友好，且消除了与使用光气相关的重大安全问题，但苯酚是一种较差的亲核试剂，转化为碳酸二苯酯的程度有限。酶催化碳酸酯单体和二醇的缩聚反应是一种更可行、更直接的酶促合成聚碳酸酯的途径。我们描述了一种在环境条件下使用酶进行AA-BB缩聚反应制备聚碳酸酯的方法。可实现高达8500 MW的分子量。与工业聚合反应不同，该过程无需使用酸催化剂、大量能量输入或高温高压即可进行。
