Poly(-caprolactone) (PCL) macromonomers capped by a polymerizable norbornene end-group have been synthesized and (co)polymerized by ring-opening metathesis with formation of graft copolymers and polymacromonomers. ␣-Norbornenyl PCL macromonomers have been synthesized by ring opening polymerization (
Enzymatic ring-opening polymerization of ε-caprolactone by a new lipase from Yarrowia lipolytica
✍ Scribed by Karla A. Barrera-Rivera; Arturo Flores-Carreón; Antonio Martínez-Richa
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 258 KB
- Volume
- 109
- Category
- Article
- ISSN
- 0021-8995
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✦ Synopsis
Abstract
A new lipase from the yeast Yarrowia lipolytica was isolated and used in the enzymatic ring‐opening polymerization of lactones. The effect of used commercial oil from a vacuum pump (instead of olive oil) and in the presence of wheat flour was evaluated. It was found that lipase production is favored when wheat flour and used commercial oil is added instead of olive oil with an incubation time of 16.5 h at 29°C and 250 rpm. Lipase shows a specific activity of 3.47 nmoles of 4‐methyl umbelliferone released/mg of protein/min. In this way, preculture step can be avoided and an important reduction in production time can be obtained. In vitro polymerization of ε‐caprolactone at different temperatures in the presence of n‐heptane for 15 days produces low‐molecular‐weight polyesters with unique multiphase morphology. Polyesters were characterized by NMR (solution and solid‐state) spectroscopy, differential scanning calorimetry (DSC), Fourier‐transformed infrared, wide‐angle X‐ray scattering and MALDI‐TOF. Polyester crystallinities calculated by DSC were high, as expected for low‐molecular‐weight PCLs. Final polymer possesses carboxylic acid and hydroxyl end‐groups, as determined by ^1^H‐ and ^13^C NMR analysis. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008
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