尿素甘油共塑化热塑性淀粉

采用尿素、甘油为塑化剂制备热塑性淀粉材料,并对改性后淀粉的力学性能、塑化效果以及结晶状况进行了探索,考察了尿素与甘油不同比例对热塑性淀粉塑化效果的影响,得出热塑性淀粉最佳塑化质量比为淀粉/尿素/甘油为100/20/20。在RH为33%的湿度环境保存1周,上述比例塑化的热塑性淀粉拉伸模量可达0.959 MPa,断裂伸长率达209.64%,且热塑性淀粉内未出现尿素自结晶,淀粉塑化效果良好。     

基于淀粉直接改性对热塑性淀粉塑化程度的影响

以玉米淀粉为原料,经酸解或酸解酯化改性后,用甘油对其进行塑化处理,利用单螺杆挤出机制备改性热塑性淀粉,并通过X-射线衍射仪、差示扫描量热仪和扫描电镜对热塑性淀粉的塑化程度进行分析。结果表明,基于不同淀粉制得的热塑性淀粉呈现出不同的结晶结构,改性处理降低了热塑性淀粉的结晶度,增大了DSC吸热峰值,经挤出成型形成更加均一的连续相,塑化程度增大,特别是热塑性酸解酯化淀粉。TGA分析表明,热塑性淀粉的热稳定性随塑化程度的增大而降低。     

全淀粉热塑性塑料及研究

主要阐述了热塑性淀粉（TPS）的塑化机理、热塑性淀粉的性质以及近年来国内外关于热塑性淀粉的研究成果。国内许多学者研究了增塑剂的种类和数量对热塑性淀粉性能的影响，淀粉改性后再塑化以及寻找新的增塑剂，但国内这种技术还处在研究阶段，还没有关于产业化和产品应用方面的报道；国外学者还研究了直链淀粉含量对热塑性淀粉性能的影响，研究了用淀粉的超小晶体作为增强剂可以提高热塑性淀粉的强度。     

淀粉的塑化研究进展

淀粉具有良好的生物降解性能,但淀粉分子中含有大量的羟基,存在较强的氢键,使得淀粉不宜直接用熔融法热塑挤出加工,因此淀粉的塑化是淀粉塑料生产的关键。对以加入增塑剂的热塑性增塑方法进行了综述,并进一步探讨了淀粉塑化的机理。     

热塑性磷酸酯淀粉的制备与性能研究

以磷酸酯淀粉为基体、甘油和水为增塑剂,使用转矩流变仪制备了磷酸酯热塑性淀粉(TPS)。研究了甘油用量对于材料的塑化性能、流变性能、结晶行为以及力学性能的影响。结果表明:随着甘油含量的增加,热塑性磷酸酯淀粉的平衡扭矩减小,熔体质量流动速率增大,流动性提高,拉伸强度与断裂伸长率先增大后减小,而且结晶度下降,塑化程度提高;当淀粉/甘油/水的质量比为60/30/8时,材料具有较好的力学性能。     

结晶行为对热塑性淀粉材料性能的影响

分析研究了儿种淀粉和热塑性淀粉的结晶性能、流变性能、力学性能以及含水量对热塑性淀粉的重结晶性能以及对材料的影响。结果表明:虽然几种淀粉的结晶度不同结晶类型不同,但淀粉的塑化性能、拉伸强度、断裂伸长率与结晶度、结晶类型无关,只与淀粉分子中直链分子链的含量有关、与淀粉的相对分子质量有关。实验结果还表明:热塑性淀粉在放置时一间内会出现重结晶现象,结晶的晶型有所转变;结晶度呈现增大趋势,其变化速度与热塑性淀粉中水含量有关,水可以促进热塑性淀粉的重结晶,甘油可以减小重结晶速度。     

强剪切作用对全淀粉塑料结构和性能的影响

选用甘油和山梨醇作为塑化剂制备热塑性淀粉,并通过设计一种具有深螺槽、短螺距和长剪切区的单螺杆挤出设备,达到提高剪切效果的作用,以增强热塑性全淀粉塑料的力学性能。通过扫描电子显微镜、傅里叶红外变换光谱仪、热分析仪以及X射线衍射仪表征了增强剪切效果对单组分与复配塑化剂对全淀粉塑料塑化效果的影响。结果表明,增塑剂可以与淀粉颗粒分子形成氢键,破坏淀粉颗粒的球晶结构,使挤出成型后的热塑性淀粉能形成均一相结构;与普通的挤出工艺相比,增塑挤出制备的热塑性淀粉具有更好的热稳定性,拉伸强度提高了17.2 %,断裂伸长率降低了18 %。     

二羟甲基脲塑化马铃薯淀粉膜的性能研究

以二羟甲基脲(DMU)作为新型塑化剂来制备热塑性淀粉膜(DPSF),并以甘油塑化马铃薯淀粉制备淀粉膜(GPSF)作为对比样,通过电子扫描显微镜、红外谱图、差示扫描量热和力学性能测试等手段分析和研究了DPSF的性质和性能.结果表明:DMU可以使淀粉塑化,使形成的膜具有连续的均一相;与甘油相比,二羟甲基脲可以与淀粉形成更强烈的氢键;吸水数据表明DPSF有较好的耐水性能;与GPSF相比,DPSF的水蒸气透过性较低.     

淀粉的热塑性研究

通过在淀粉中加入增塑剂，制备热塑淀粉，研究了3种不同淀粉－玉米淀粉，木薯淀粉和可溶性淀粉的增塑性情况，研究了甘油、乙二醇、山梨醇、聚乙烯醇4种塑剂的增塑效果，不同的淀粉品种及不同增塑剂的产品性能有所不同。在显微镜下观察到，淀粉经塑化后，次价键断裂，晶区被破坏，使淀粉具备了热塑性，可以加工成薄膜。     

热塑性淀粉/黄麻复合材料的研究

以玉米淀粉为原料,以甘油和尿素为增塑剂制备了热塑性淀粉(TPS),并与黄麻(F)进行共混制备了复合材料(TPS/F).对共混条件以及黄麻用量对材料力学性能和耐水性的影响进行了研究.结果表明:在转矩流变仪中转速越高越有利于淀粉的塑化.以尿素为增塑剂制备的热塑性淀粉(UTPS)的拉伸强度(13 MPa)高于以甘油为增塑剂的热塑性淀粉(GTPS)的拉伸强度(7 MPa),而在加入黄麻后,当黄麻质量分数为20%时,GTPS/F的拉伸强度高达26.8 MPa,高于UTPS/F.黄麻的加入也提高了UTPS的耐水性,但GTPS的耐水性仍较差.     

生物可降解热塑性淀粉的开发

简要地介绍了热塑性淀粉（ＴＳ）的研究动态，重点介绍热塑性淀粉的加工原理，加工设备，热塑性淀粉的结构和性能，讨论热塑性淀粉的品种和其相应的应用领域，热塑性淀粉开发中存在的问题和应用前景。     

Structure and properties of compression-molded thermoplastic starch materials from normal and high-amylose maize starches

The structural and mechanical properties of compression-molded normal and high-amylose maize starches were studied as a function of processing water content and ageing time. Rubbery thermoplastic starches were produced by compression molding of four maize starches with differences in amylose content and amylopectin structure. Glycerol (30% on the basis of dry starch) and water (between 10 and 35% on the basis of total mass) were used as plasticizers. After processing, the amorphous thermoplastic starch materials crystallized during ageing. The semicrystalline materials contained both E-type and V-type, as well as B-type crystallinity. The properties of the thermoplastic starch materials are dependent on water content during processing, starch source, and ageing time. The normal maize starch materials are highly flexible with elongations between 56 and 104%. The elongations of the high-amylose maize starch materials were between 5–35%. The tensile stress and E-modulus of the normal maize starch materials were in the range of 3.9–6.7 and 27–131 MPa, respectively. The tensile stress and E-modulus of the high-amylose maize starch materials increased from approximately 0.5 to 23 and 5 to 700 MPa, respectively, with increasing water content during processing from 10 to 35%. The differences in mechanical properties of the normal and high-amylose materials were explained by differences in the structure of the amylose and amylopectin structure. It was concluded that both lead to differences in the starch network. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 631–644, 1997     

不同直链含量热塑性淀粉的制备及性能研究

利用转矩流变仪,以丙三醇为增塑剂对不同来源的淀粉进行改性制备热塑性淀粉（TPS）。采用X射线衍射仪（XRD）、热重分析仪（TG）、水接触角测量仪、傅里叶变换红外光谱仪（FTIR）和扫描电子显微镜（SEM）等对获得的热塑性淀粉进行了表征。结果表明,4种热塑性淀粉均含有颗粒状和颗粒状碎片,并且在热塑性木薯淀粉中所含比例更高;淀粉在增塑过程中达到稳态的扭矩依次为木薯淀粉（23 N·m）>玉米淀粉（21 N·m）>马铃薯淀粉（17.8 N·m）>蜡质玉米淀粉（15.2 N·m）,这与不同种类来源淀粉的直链淀粉比例差异直接相关;不同类型的淀粉与增塑剂形成氢键的能力存在差异,蜡质玉米淀粉的能力最强;4种热塑性淀粉的亲水性依次为热塑性木薯淀粉（75.9 °）>热塑性玉米淀粉（69.2 °）>热塑性马铃薯淀粉（67.9 °）>蜡质玉米淀粉（64.9 °）。     

New breathable films using a thermoplastic cross‐linked starch as a porogen

Breathable films, which find in variety of product applications, are conventionally made using mineral porogens such as calcium carbonate (CaCO₃). This article addresses a novel biodegradable and highly breathable film without inorganic porogens. Unexpectedly, a thermoplastic cross‐linked natural polymer (corn starch) was used successfully to create tortuous passages for film breathability. This concept was demonstrated using two types of thermoplastic cross‐linked corn starches as porogens and contrasted to control samples: native corn and chemically cross‐linked starches, respectively. The films discussed had increased breathability and mechanical properties relative to the control samples. The film morphology reveals that filler was irregular when thermoplastic starch or CaCO₃ was used. The difference in filler from chemically modified cross‐linked starch and thermoplastic cross‐linked starch was observable as well. It is believed that spherical particles provided by thermoplastic cross‐linked starch helps film debonding and porosity during the film stretch processes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41016.     

Thermoplastic starch blends with a poly(ethylene-co-vinyl alcohol): Processability and physical properties

We investigated the effect of poly(ethylene-co-vinyl alcohol) (EVOH) concentration on the processability and physical properties of thermoplastic starch plasticized with glycerine and water. Waxy maize starch (Amioca), native corn starch (Melogel), and a treated high amylose corn starch (Hylon VII) were employed to explore the effect of starch type on blend properties. All the starches exhibited similar changes in properties with increasing EVOH content. The minimum injection pressure required for filling a standard test specimen (a measure of processability) decreased with increasing EVOH concentration and provided an indication of improved processability. Blends with high amylose corn exhibited higher injection pressures than the corresponding waxy maize or native corn starch blends. The ductility of all the thermoplastic starches was significantly increased upon the addition of EVOH. The waxy maize blends were stiffer and the high amylose corn blends exhibited higher elongation at low EVOH concentrations, but all the starch/EVOH blends exhibited similar physical properties when the EVOH concentration was ≥ 50 wt%. An investigation of physical properties of this blend series after long term aging from 10% to 90% relative humidity is in progress. Future studies include rheology, electron microscopy, and thermal analysis to more fully elucidate phase behavior in these binary blends.     

连续纤维增强热塑性预浸料制备工艺与发展趋势

总结了国内外连续纤维增强热塑性预浸料的主流浸渍及成型工艺,包括热熔法、溶液浸渍、粉末浸渍、薄膜堆叠、混编法、原位聚合等,对比了不同工艺在原料、设备、加工流程等方面的优缺点,并对热塑性预浸料成型模具的设计与应用进行了讨论;同时,阐述了热塑性预浸料的发展现状,介绍了更加轻量化的浸渍技术以及包括三维连续编织技术在内的多样化的...     

聚氨酯改性热塑性淀粉结构与性能的研究

利用环境友好的方法制备韧性且疏水性的改性淀粉材料是很重要的.在我们的工作中,用甲苯二异氰酸酯(TDI)和蓖麻油成功合成聚氨酯预聚体,然后在密炼机中用该预聚体改性热塑性淀粉TPS.热塑性改性淀粉材料成功制备并测试分析.结果表明比较纯淀粉,由于淀粉和弹性聚氨酯颗粒之间很强的相互作用,改性淀粉的疏水性和韧性方面得到很大提高.     

淀粉基聚乙烯醇热塑加工研究进展

阐述了淀粉和聚乙烯醇的分子结构,探讨了淀粉和聚乙烯醇热塑加工的机理及研究进展。重点对国内外淀粉基聚乙烯醇在热塑加工方面的研究进行了深入分析,并对我国淀粉基聚乙烯醇材料的应用前景进行了展望。     

微量离子液体对聚乙烯醇热稳定性的影响研究

聚乙烯醇由于其分解温度与熔融温度接近,长期以来一直存在热塑性加工难的问题。希望采用少量离子液体作为聚乙烯醇(PVA)的热稳定剂,提高PVA热分解温度,从而获得PVA的热塑性加工窗口。实验结果表明:离子液体可使PVA的热分解温度及最快分解温度得到极大的提高。与纯的PVA相比,甲基丙烯酰氧乙基三甲基氯化铵(DMC,0. 6%)和1-乙烯基-3-乙基咪唑四氟硼酸盐(BF4IL,3%)的加入分别为PVA提供了一个约90℃和100℃的加工窗口,并且它们的加入几乎不会影响PVA本身优异的透光性能。这将为PVA膜的热塑性加工提供出一个新的思路。     

热塑性弹性体的挤出和螺杆设计

概述了热塑性弹性体的挤出加工条件和挤出螺杆的设计要求,并通过分析比较指出,对于某一类热塑性能体的挤出加工来说,即便其组成材料相同而中是组分比例有差异,也很难从整体上给出统一的加工条件和螺杆设计的特定规则。