【作者】 高伟；

【导师】 侯汉学；

【作者基本信息】 山东农业大学 ， 食品科学， 2012， 硕士

【摘要】 本文以羟丙基交联淀粉为基材，以有机改性蒙脱土为增强剂，采用双螺杆造粒，单螺杆挤出吹塑制得淀粉蒙脱土纳米复合膜。测定了淀粉膜的力学、透水、透光、色度、热稳定性能等指标，并通过X-射线衍射（XRD）、透射电镜（TEM）、红外光谱（FTIR）、扫描电镜（SEM）、差示扫描量热（DSC）和热重分析（TGA）等分别从纳米结构、分子作用力和微观形貌等方面对其进行理论分析。主要研究结果有以下几点：1、不同亲水性有机改性蒙脱土均不同程度的增大了淀粉膜的拉伸强度，提高了阻水性能。其中淀粉-DK3复合膜的拉伸强度达2.47MPa，水蒸气透湿系数4.31×10^-10g.m/m².s.Pa。XRD和TEM分析显示淀粉分子进入有机改性蒙脱土片层之间形成插层结构； FTIR分析表明有机改性蒙脱土的添加抑制了淀粉和甘油之间的塑化作用；DSC分析表明有机改性蒙脱土的添加降低了淀粉膜的玻璃化转变温度（T_g）；SEM分析显示有机改性蒙脱土有利于淀粉膜微观形貌的均匀化。中等亲水性有机改性蒙脱土DK3（Cloisite Na+）更适合与羟丙基交联淀粉复合制膜。2、随着DK3添加量的增加（0-15%），淀粉膜的拉伸强度不断增大，透湿系数减小，颜色趋于暗黄色，DK3含量15%时，淀粉膜的拉伸强度为3.37MPa，水蒸气透湿系数为5.14×10^-10g.m/m².s.Pa； TGA分析表明淀粉膜失重50%时，含15%DK3的淀粉膜对应温度最高；XRD显示DK3含量对衍射峰的位置影响不大；FTIR说明DK3添加量越大，其对淀粉和甘油之间的塑化抑制作用越明显；XRD和FTIR分析还表明增加甘油含量，会抑制淀粉和DK3之间插层结构的形成。3、添加小分子糖后，淀粉膜拉伸强度减小为1.73MPa，断裂伸长率增加为142%，水蒸气透湿系数增大为4.78×10^-10g.m/m².s.Pa，结晶度降低；SEM显示小分子糖使淀粉膜微观形貌更加均一； XRD和FTIR分析表明小分子糖和DK3竞争与淀粉之间的相互作用。4、挤压吹塑工艺（牵拉比、吹胀比和温度）对淀粉膜性能影响。增大牵拉比（TUR）和吹胀比（BUR），淀粉膜的拉伸强度均先增大后减小；升高温度，淀粉膜的拉伸强度降低，断裂伸长率升高；增大牵拉比和吹胀比，淀粉膜水蒸气透过率和透明度均增大；升高温度，水蒸气透过量增大，而透明度则降低，淀粉膜表面淀粉颗粒减少，微观形貌更加均匀。更多还原

【Abstract】 In this research, the composite films by extrusion blowing were prepared fromhydroxypropyl distarch phosphate （HPDSP） and enhanced with organically modified clays.The Mechanical property, Permeability, Transparency, Colour and Thermal stability of filmswere determined to evaluate the film. Nanostructure, Molecular force and Micro morphologyof films were determined through X-ray diffraction （XRD）, transmission electron microscopy（TEM）, Fourier Transform Infrared Spectroscopy （FTIR）, Scanning electron microscope（SEM）, Differential scanning caborimetry （DSC） and Thermal Gravimetric Analysis （TGA）.The main results were as follows:1、With the addition of organically modified clays with different hydrophilic properties,significantly greater tensile strength and lower water vapor permeability were obtained.Tensile strength of starch-DK3film increased to2.47MPa, while water vapor permeabilitydecreased to4.31×10^-10g.m/m².s.Pa. XRD and TEM showed starch entered the silicate layersand formed intercalated starch-clay nanocomposite. FTIR showed that clays inhibited theplastication between starch and glycerol to some extent. DSC showed that the intermolecularattraction of thermoplastic starch matrix seemed to be interrupted by the charged clays. Andsubsequently the film backbone chains gained additional segmental mobility which led to thedecrease of Tg.. SEM indicated starch had a more homogeneous phase, with the addition ofclays. It turned out that DK3which had a medium hydrophilic property was more efficient instarch films preparation than other clays due to its good compatibility with HPDSP.2、With DK3content increased from0to15%, significantly greater tensile strength（3.37MPa） and lower water vapor permeability (4.31×10^-10g.m/m².s.Pa) were obtained. Thecolor of films tended to be yellowish. With the increase of DK3from0to15%, thetemperature of50%weight loss of the films increased. XRD showed that DK3concentrationhad little effect on the peak position. FTIR showed that DK3inhibited the plasticationbetween starch and glycerol more markedly, with the increase of DK3from0to15%. XRDand FTIR also indicated that higher glycerol content could inhibit the interaction betweenstarch and DK3. 3、Sugars （glucose, fructose and sucrose） were good plasticizers which improved filmflexibility （E:142%） and caused a reduction in barrier (WVP up to4.78×10^-10g.m/m².s.Pa)and tensile （TS:1.73MPa） properties. SEM indicated starch films showed a morehomogeneous phase, with the addition of Sugars. It was the addition of sugars （sucrose,fructose and glucose） to the glycerol plasticized starch-clay systems that inhibited theformation of intercalation structure by XRD and FTIR results.4、With take-up-ratio and blow-up-ratio increased, tensile properties firstly increasedthen decreased, while elongation at break showed a reverse trend. Water vapor permeabilityand transparency increased. With rising temperature, tensile properties and transparencydecreased, while water vapor permeability increased. At high temperature, Starch granuleswere disrupted and the homogeneous materials were obtained by SEM results.更多还原