caa a22 4500 475782968 CHVBK 20180406123649.0 cr unu---uuuuu 170329e20000801xx s 000 0 eng 10.1023/A:1008948325177 doi (NATIONALLICENCE)springer-10.1023/A:1008948325177 Synthesis of acrylate functional telechelic poly(lactic acid) oligomer by transesterification [Elektronische Daten] [Ge´raldine Coullerez, Christian Lowe, Peter Pechy, Hans Kausch, Jo¨ns Hilborn] The controlled synthesis of low molecular weight (Mn from 700 to 10 000 g/mol) poly(lactic acid) (PLA) telechelic oligomers end-capped with acrylate groups by a one-step reaction was investigated. A transesterification reaction was carried out in solution with a Lewis acid titanium catalyst using a high molecular weight PLA and a low molar mass diacrylate. End-functionalization was demonstrated by proton NMR spectroscopy which was also used for quantitative analysis and number average molecular weight determination using the ratio between the acrylic chain ends to the main groups of poly(D,L-lactic acid). The formation of low molar mass oligomers from high molecular weight poly(lactic acid) was verified by gel permeation chromatography. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry showed that the above oligomerization was accompanied by the formation of cyclic compounds. By these means the feasability of a simple transesterification for a controlled synthesis of telechelic oligomers with molecular mass being a function of the added amount of diacrylate has been demonstrated. The glass transition temperatures of the elaborated oligomers varied from −35 to −5 °C. Subsequent thermal crosslinking was performed using benzoyl peroxide which enabled the formation of amorphous networks with Tg's close to the body temperature of 40 °C. Upon storage in a humid atmosphere the initially fairly hard and brittle networks became, due to hydrolysis, progressively more flexible thus demonstrating the potential biodegradability of these materials. Kluwer Academic Publishers, 2000 Coullerez Ge´raldine Physical Chemistry Institute, Swiss Federal Institute of Technology, CH-1015, Lausanne, Switzerland aut Lowe Christian Physical Chemistry Institute, Swiss Federal Institute of Technology, CH-1015, Lausanne, Switzerland aut Pechy Peter Physical Chemistry Institute, Polymers Laboratory, Materials Department, Swiss Federal Institute of Technology, CH-1015, Lausanne, Switzerland aut Kausch Hans Physical Chemistry Institute, Swiss Federal Institute of Technology, CH-1015, Lausanne, Switzerland aut Hilborn Jo¨ns Physical Chemistry Institute, Swiss Federal Institute of Technology, CH-1015 Lausanne, Switzerland aut Journal of Materials Science: Materials in Medicine Kluwer Academic Publishers 11/8(2000-08-01), 505-510 0957-4530 11:8<505 2000 11 10856 https://doi.org/10.1023/A:1008948325177 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1008948325177 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Coullerez Ge´raldine Physical Chemistry Institute, Swiss Federal Institute of Technology, CH-1015, Lausanne, Switzerland aut NATIONALLICENCE 700 1- Lowe Christian Physical Chemistry Institute, Swiss Federal Institute of Technology, CH-1015, Lausanne, Switzerland aut NATIONALLICENCE 700 1- Pechy Peter Physical Chemistry Institute, Polymers Laboratory, Materials Department, Swiss Federal Institute of Technology, CH-1015, Lausanne, Switzerland aut NATIONALLICENCE 700 1- Kausch Hans Physical Chemistry Institute, Swiss Federal Institute of Technology, CH-1015, Lausanne, Switzerland aut NATIONALLICENCE 700 1- Hilborn Jo¨ns Physical Chemistry Institute, Swiss Federal Institute of Technology, CH-1015 Lausanne, Switzerland aut NATIONALLICENCE 773 0- Journal of Materials Science: Materials in Medicine Kluwer Academic Publishers 11/8(2000-08-01), 505-510 0957-4530 11:8<505 2000 11 10856 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer