【摘要】 目的:研究淀粉在挤压吹塑过程中粉、母粒、膜三态的结构演变规律。方法:以羟丙基二淀粉磷酸酯为原料,通过挤压吹塑制备淀粉膜。采用傅里叶红外光谱—衰减全反射(FTIR-ATR)、X-射线衍射(XRD)、热稳定分析仪(TGA)、凝胶渗透色谱(GPC)等技术手段,分析淀粉在粉态、母粒态和膜态下的结晶结构、热稳定性及分子结构变化。结果:经挤压后,淀粉晶型由粉态的A型转变为母粒态和膜态的V型,且膜态样品的衍生峰强度相比于母粒态增加;淀粉分子发生降解导致相对分子质量降低;同时,三态样品的水分含量和溶解度呈不同的变化趋势。结论:挤压吹塑过程中,挤压机的高温、高剪切,促进成了膜组分间的相互作用,破坏了淀粉分子结构。更多还原

【Abstract】 Objective: In order to study the structure evolution of three states of powder, masterbatch and film of starch during extrusion blowing. Methods: Using hydroxypropyl distarch phosphate as raw material, starch film was prepared by extrusion blow molding. Using Fourier Infrared Spectroscopy-Attenuated Total Reflectance(FTIR-ATR), X-ray Diffraction(XRD), Thermal Stability Analyzer(TGA), Gel Permeation Chromatography(GPC) and other technical means, crystal structure, thermal stability and molecular structure changes of the starch were analyzed in powder state, masterbatch state and film state. Results: After extrusion, the starch crystal form changed from powder state A to masterbatch state and film state V, and the derived peak intensity of the film state sample increased compared with the masterbatch state; the degradation of starch molecules resulted in the relative molecular mass at the same time, and the moisture content and solubility of the three-state samples show different trends. Conclusion: In the extrusion blow molding process, the high temperature and high shear of the extruder promote the interaction between the film-forming components and destroy the molecular structure of starch.更多还原