Melt-processing, moisture-resistance and strength retention properties of supercritical CO2-processed thermoplastic starch resins

作者：Peng, X. L.; Kuo, M. C.; Huang, C. Y.; Wei, W.; Wang, D. W.; Sun, L. S.; Runt, J.; Yeh, J. T.^*

来源：Express Polymer Letters, 2018, 12(5): 462-478.

DOI：10.3144/expresspolymlett.2018.39

• biodegradable polymers
• supercritical carbon dioxide
• thermoplastic starch
• moisture resistance
• strength retention

This paper represents the first report of thermoplastic starch (scCO(2)TPS) and glutaraldehyde (GA) modified TPS resins (scCO(2)TPS(100)GA(x)), gelatinized and/or modified with the aid of supercritical carbon dioxide (scCO(2)). The melt flow rate, initial and retention values of tensile strength (sigma(f)) of TPS and GA-modified TPS prepared using scCO(2) fluid were considerably higher than those of TPS and TPS(100)GA(x) materials prepared in the conventional way. After conditioning at 20 degrees C/50% RH for 56 days, the sigma(f) of properly prepared scCO(2)TPS(100)GA(0.1) still remained at 17.5 MPa, which is around 3.5 times of that of the corresponding conditioned TPS(100)GA(0.1). The moisture contents of conditioned scCO(2)TPS and scCO(2)TPS(100)GA(x) were considerably lower than those of the corresponding TPS and TPS(100)GA(x) aged for the same amounts of time. Conditioned scCO(2)TPS and scCO(2)TPS(100)GA(x) exhibited only V-h-type crystals with melting temperatures similar to 20 degrees C lower than those of corresponding conditioned TPS and TPS(100)GA(x). In comparison to TPS and TPS(100)GA(x), more dissociated amylopectin chains with loosely hydrogen-bonded -OH groups and significantly less retrogradation was found for conditioned scCO(2)TPS and scCO(2)TPS(100)GA(x).

• 出版日期2018-5
• 单位湖北大学; 武汉工程大学