Enzymatically catalyzed polycondensation of p-xylylenediamine and diethyl sebacate resulted in oligo(p-xylylene sebacamide) with high melting temperatures (223-230 °C) and the enzymatic polycondensation of dimethyl terephthalate and 1,8-diaminooctane leads to oligo(octamethylene terephthalamide) with two melting temperatures at 186 and 218 °C. No oligoamides, but products 1 and 2, were formed from the enzymatic reaction of dimethyl terephthalate and p-xylylenediamine. All reactions were catalyzed by CAL-B, icutinase, or CLEA cutinase. All reactions catalyzed by CAL-B show higher conversion than reactions catalyzed by icutinase or CLEA cutinase. The highest DPmax of 15 was achieved in a one-step and two-step synthesis of oligo(p-xylylene sebacamide) catalyzed by CLEA cutinase.

Fusarium solani pisi cutinase-catalyzed synthesis of polyamides Stavila, E.; Arsyi, R. Z.; Petrovic, D. M.; Loos, K. a b s t r a c tPolyamides, or nylon, are widely used in fiber and engineering plastic materials, due to their good mechanical and thermal properties. Synthesis of oligomers from nylon-4,10, nylon-6,10, and nylon-8,10 were performed via polycondensation of diamines (1,4-butanediamine, 1,6-hexanediamine, and 1,8-diaminooctane) and diester (diethyl sebacate). These reactions were catalyzed by immobilized cutinase from Fusarium solani pisi on Lewatit beads, cutinase in the form of cross-linked enzyme aggregates (CLEA), or by immobilized Lipase B from Candida antarctica (N435). The highest maximal degree of polymerization (DP max ), up to 16, can be achieved in the synthesis of nylon-8,10 catalyzed by CLEA cutinase in diphenyl ether at 70°C. By performing a reaction at cutinase optimal temperature (70°C), CLEA cutinase in the synthesis of nylons shows good catalytic activity, like N435.

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Synthesis of lactams using enzyme-catalyzed aminolysis Stavila, E.; Loos, K.

A facile method to synthesize rGO using a microwave-assisted method under N2-atmosphere conditions is reported.

The enzymatic ring-opening copolymerization of ε-caprolactone (ε-CL) and β-lactam by using Candida antarctica lipase B (CAL-B) as catalyst was studied. Variation of the feed ratios of 25:75, 50:50, and 75:25 of ε-CL/β-lactam was performed. The products contain poly(ε-CL-co-β-lactam) and the homopolymers of poly(ε-CL) and poly(β-lactam). The structure of the copolymers was determined by MALDI-ToF MS. Poly(ε-CL-co-β-lactam) has an alternating and random structure consisting of alternating repeating units with oligo(ε-CL) or oligo(β-lactam). The highest fraction of the alternating copolymers resulted from the reaction with a feed ratio 50:50. The copolymer is a semicrystalline polymer with a T m at 124 °C and T g s at −15 and 50 °C. Interestingly, the copolymer also demonstrated cold crystallization at 29 and 74 °C, after quenching the sample from the melt in liquid nitrogen.

The possible explanations on how the existence of copper, CuO, or Cu2O influences the electrical conductivity and electrochemical properties of rGO.

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