کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5186677 | 1381111 | 2006 | 8 صفحه PDF | دانلود رایگان |
High molecular weight poly(α-methyl β,l-malate) (Mn â¼Â 25,000, PD â¼Â 1.7) was prepared from microbial poly(β,l-malic acid) (Mn â¼Â 29,000, PD â¼Â 1.3) by methylation with diazomethane in dry acetone without substantial cleavage of the polyester main chain. The thermal properties of this poly(malate) were assessed and its crystal structure was preliminary examined. Two crystal forms were identified by X-ray diffraction, their occurrence being dependent on crystallization conditions. The kinetics of nonisothermal and isothermal crystallizations from the melt were studied and modelled using the Avrami approach. Results were compared to those recently reported by us for low molecular weight poly(α-methyl β,l-malate) (Mn â¼Â 3000, PD â¼Â 1.3).
Journal: Polymer - Volume 47, Issue 19, 7 September 2006, Pages 6501-6508