Lipase-Catalyzed Ring-Opening Copolymerization of ε‑Caprolactone and β‑Lactam

• Published in: Biomacromolecules Vol. 15; no. 1; pp. 234 - 241
• Main Authors: Stavila, E, Alberda van Ekenstein, G. O. R, Woortman, A. J. J, Loos, K
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 13-01-2014
• Subjects: Applied sciences; beta-Lactams - chemistry; beta-Lactams - metabolism; Candida antarctica; Caproates - chemistry; Caproates - metabolism; Catalysis; Copolymerization; Exact sciences and technology; Fungal Proteins - chemistry; Fungal Proteins - metabolism; Lactones - chemistry; Lactones - metabolism; Lipase - chemistry; Lipase - metabolism; Organic polymers; Physicochemistry of polymers; Polymers - chemistry; Polymers - metabolism; Preparation, kinetics, thermodynamics, mechanism and catalysts; Catalytic reaction; Lactone copolymer; Molecular structure; Enzyme; Triacylglycerol lipase; Enzymatic catalysis; Solution copolymerization; Esterases; Experimental study; Thermal stability; Carboxylic ester hydrolases; Caprolactone copolymer; Amide copolymer; Hydrolases; Microstructure; Catalyst activity; Ring opening copolymerization; Aliphatic copolymer
• ISSN: 1525-7797; 1526-4602
• DOI: 10.1021/bm401514k

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 gs 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.