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 文獻名： Characterization of citric acid/glycerol co-plasticized thermoplastic starch prepared by melt blending

 

作者：Rui Shia, , Zizheng Zhanga, Quanyong Liua, Yanming Hana, Liqun Zhanga, , Dafu Chenb, , Wei Tianc

a The Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, Beijing 100029, People’s Republic of China

b Laboratory of Bone Tissue Engineering of Beijing Research Institute of Traumatology and Orthopaedics, Beijing 100035, People’s Republic of China

c Department of Spine Surgery of Beijing JiShuiTan Hospital, The Fourth Clinical Medical College of Peking University, Beijing 100035, People’s Republic of China

 

摘要：A novel citric acid (CA)–glycerol co-plasticized thermoplastic starch (CGTPS) was prepared by melt blending. The CA content varies from 10% to 40 wt%. Result from Fourier Transform Infrared spectroscopy (FTIR) show that partial esterification occurred during blending. The degrees of substitution and esterification increased as the CA content increased. Results from intrinsic viscosity measurement, laser light scattering (LLS), and FTIR demonstrate the molecular weight of starch decreased as the CA percentage increased. The weight average molecular weight (Mw) of CGTPS with 20 wt% CA was only one-tenth of that without CA under the same processing conditions. Crystal type and crystallinity changes as a function of CA were recorded by X-ray diffraction (XRD). Thermal stability and the glass transition temperature (Tg) were detected by thermogravimetric (TG) and differential scanning calorimeter (DSC). Compared to the traditional GTPS, the novel CGTPS exhibits the special characters of partial esterification, low molecular weight and stronger interaction between starch and plasticizers. These new properties can be expected to prevent retrogradation, promote compatibility with polyesters, improve the processing ability, and adjust the degradation properties.

 

關鍵詞：Corn starch; Citric acid; Glycerol; Thermoplastic; Melt blending