国内外淀粉基生物降解材料制备方法的研究进展

本文综述了国内外食品包装用淀粉基生物降解薄膜制备方法的研究进展。     

淀粉基木材胶粘剂的合成及性能研究

以玉米淀粉为接枝骨架,过硫酸铵为引发剂,与接枝单体乙酸乙烯酯-丙烯酸乙酯进行接枝共聚反应,制取淀粉基木材胶粘剂。对得到的淀粉接枝共聚物进行了表征分析及性能研究。IR谱图表明,样品除了保持淀粉的特征吸收峰外,在1730～1740cm-1之间出现了羰基特征吸收峰;X-粉末衍射谱图表明,样品多为弥散峰,证明淀粉接枝共聚物基本为少量结晶态与无定形态共存的结构;TG、DTA曲线证实了接枝共聚反应的发生,且淀粉接枝共聚物的热稳定性优于纯玉米淀粉;性能测试结果表明,制备的胶粘剂具有较好的高温稳定性、粘接性、耐寒性和储存稳定性;各项指标已达到了国家标准HG/T2727-95中聚乙酸乙烯酯木材胶粘剂的性能指标,特别是压缩剪切干强度远远超过了国家标准。     

淀粉基可食性餐具热压成型的试验研究

通过热压成型及交叉试验法,研究了含水率、成型压力、初始温度、最终温度、定型时间、保温时间等因素对淀粉基可食性降解餐具的耐水性能、耐油性能和负重性能的影响,为淀粉基可食性餐具的开发提供试验依据.     

绿色耐盐性淀粉基高吸水性树脂的制备及抑尘效果研究

以淀粉、丙烯酸和丙烯酰胺为主要原料,水溶液聚合法制备了绿色高吸水性树脂。考察了中和度、引发剂用量、交联剂用量、单体质量比及淀粉用量等实验条件对吸水率的影响。最佳条件下制备的树脂在蒸馏水和自来水中的吸水率分别为815.4和208.7g/g。对树脂的耐蒸发性与抑尘性进行了研究,结果表明树脂对黄土有较好的抑尘效果,可作为抑尘剂使用。采用红外光谱法对树脂结构进行了分析。     

淀粉基可降解塑料的研究进展

简述了淀粉基塑料的三个大类,主要介绍可完全降解的聚乳酸淀粉塑料、聚乙烯醇淀粉塑料、聚己内酯淀粉塑料,全淀粉塑料。分析了淀粉基塑料存在的主要问题、国内外的研究现状、研究热点,并对其未来的发展趋势进行了展望。     

淀粉基可生物降解塑料的研究现状

发展淀粉基可生物降解塑料有利于节省石油资源、保护环境.国内外这方面的研究较多,并且在技术的实用性方面也取得了较大进展.目前研究热点集中在3个方向:淀粉与其它可生物降解高分子的直接填充;对淀粉表面修饰使其能与合成高分子相容;在淀粉与合成高分子体系中加入增塑剂.虽然淀粉基可生物降解塑料在综合性能上还不能与合成高分子相比,但由于淀粉的综合优势,淀粉基可生物降解塑料的研究和发展极具潜力.     

淀粉基环境可降解高分子材料研究进展

介绍了淀粉的基本性质,阐述了两类淀粉基环境可生物降解高分子材料的研究开发和发展现状,讨论了其制备原理、方法和存在的问题,并指出了发展方向.     

淀粉基热塑性发泡材料的配方研究

以玉米淀粉为基体、竹粉为增强体,甘油/邻苯二甲酸二辛酯（DOP）混合物作为增塑剂,偶氮二甲酰胺（AC）/氧化锌（ZnO）为发泡剂,聚乙烯醇（PVA）为相容剂,用注塑发泡法制备淀粉基热塑性发泡材料（NFSC）。通过研究不同助剂配比及添加量对NFSC的相容性、力学性能、塑化效果及发泡效果的影响,优化配方设计,改善材料性能,以得到高品质、轻量化的淀粉基热塑性发泡材料。研究表明：甘油/ DOP质量比为6:1,且添加质量分数为30%时,NFSC的塑化效果良好;AC/ZnO质量比为2:1,且添加质量分数为3%时,NFSC的发泡效果良好;添加PVA质量分数约为11%时,竹粉与淀粉基体间界面相容性较好。     

淀粉基塑料购物袋性能表征研究

目的 通过对淀粉基塑料购物袋的理化性能表征,了解淀粉基塑料购物袋使用特性,为改善淀粉基塑料购物袋使用性能提供一些理论依据。方法 采用热重分析(TG)、热机械分析(TMA)等手段对淀粉基塑料购物袋的淀粉含量及耐热性能进行分析,借助电子万能材料试验机对淀粉基塑料购物袋的力学性能进行分析,以及利用霉菌培养、总迁移行为探究等方法对淀粉基塑料购物袋霉变程度、卫生性能进行分析。结果 样品A、B、C淀粉质量分数分别为15.72%、23.97%、30.36%,耐热性能比传统PE塑料袋要低;淀粉基塑料购物袋的拉伸强度随淀粉含量的增大而减小,断裂伸长率随淀粉含量的增加而增加,总迁移量结果随淀粉含量增加而增大,但经三氯甲烷处理后均低于限量要求;淀粉基塑料购物袋不适宜盛装酸性和低乙醇类食品。结论 通过对淀粉基塑料购物袋深入研究,发现淀粉基塑料购物袋在力学性能、总迁移量、霉变程度存在缺陷,望研究者们可以从这几个方向入手,改善淀粉基塑料购物袋的理化性能。     

氧化淀粉基复合材料的制备及力学性能

为提高淀粉基复合材料的力学性能,采用对原生淀粉进行氧化改性,通过模压发泡工艺制备了氧化淀粉基复合材料(OS复合材料)。力学测试结果表明,OS复合材料在力学性能方面有很大程度的提升,且最佳氧化比为m(淀粉)∶m(H_2O_2)=10∶1.5。此时拉伸强度为3.05 MPa,压缩强度6.724 MPa,与原生淀粉基复合材料相比分别提高21.03%、14.65%,缓冲性能最佳;其压缩强度明显优于聚苯乙烯发泡塑料(EPS),缓冲系数与EPS接近。为揭示性能变化的内在机理,通过红外光谱分析发现,氧化过程使得淀粉内部官能基团改变,形成更强的氢键,与剑麻纤维的结合更紧固;通过X射线衍射分析得到,淀粉氧化改性后,结晶度降低,内部形成更均匀的相,裸露的支链增多,其与剑麻纤维结合得更好。为探究复合材料的界面结合情况,采用扫描电镜观察,图像显示OS复合材料内部生成了较好的泡孔结构,并且其淀粉基质均匀地附着在纤维的表面,淀粉和纤维形成了很好的结合。     

全热交换机能材料的性能试验研究

参照JIS标准的有关评价标准,从材料的透湿性、透气度、易燃性方面对15种全热交换机能材料的性能进行评价,对影响性能的有关因素进行了分析研究,同时为提高性能提出一些建议。     

Research progress of starch-based biodegradable materials: a review

With the enhancement of global environmental protection awareness, new eco-friendly packaging materials have gained more and more attention since the new century. Starch is one of the most potential natural biodegradable materials due to its abundant source, low price, and completely degradable characteristics. Starch-based materials with excellent biodegradability can be widely used by improving their properties. This review starts with the structure of starch and summarizes its phase transition during processing related to the packaging materials. Then, we expound on the development stage of starch-based biodegradable materials and starch modification. This part focuses on the research of starch-based composites formed by starch derivatives, including nano-starch. Besides, extrusion molding and other modern molding methods are described in detail. Through the systematic elaboration of the above contents, the connection among structure, phase transition, and processing can be found, which can better broaden the application of starch-based biodegradable materials. Finally, various applications of starch-based materials and prospects for its future research are discussed. It is hoped to provide the basic theory and reference for the research of starch-based biodegradable materials.

     

Techniques applied to the study of microbial impact on building materials

This paper presents various techniques for materials characterisation in relation with the question of microbial impact. Application examples of some of these techniques are described as well as the respective results obtained by researchers working in this field. Additional readings are also reported.     

An experimental study of carbon-carbon composite materials

A systematic exploratory development study of the mechanical behaviour of pyrolyzed organic resin matrices reinforced with high performance carbonaceous fibres was performed. Fourteen combinations of fibre and precursor matrices in unidirectional composite form were fabricated and tested. Physical, thermal, and mechanical properties were determined at various process stages. A principal conclusion was that it is the very poor interfacial bond which is typically achieved between fibres and matrix that accounts for the low mechanical properties which are commonly observed. This poor bond was attributed primarily to the mismatch between the transverse thermal expansion coefficient of the graphite fibres and the thermal expansion coefficient of the surrounding matrix. Among the recommendations made is that the carbonization/graphitization conditions be modified to promote better interfacial bonding.Consultant, Philco-Ford Corporation.     

Preliminary study on human protein adsorption and leukocyte adhesion to starch-based biomaterials

In this study, the adsorption of human serum albumin (HSA), fibronectin (FN) and vitronectin (VN) onto the surface of novel biodegradable materials was evaluated by immunostaining. Specifically, polymeric blends of corn starch with cellulose acetate (SCA), ethylene vinyl alcohol copolymer (SEVA-C), and polycaprolactone (SPCL) were immersed in unitary and competitive systems; that is, binary and more complex protein solutions. For binary solutions, different HSA and FN protein distribution patterns were observed depending on the starch-based surface. Furthermore, the relative amount of proteins adsorbed onto starch-based surfaces was clearly affected by protein type: a preferential adsorption of VN and FN as compared to HSA was observed. On tests carried out with unitary, binary and more complex solutions, it was found that vitronectin adsorption ability was enhanced in competitive systems, which was associated with a lower amount of adsorbed albumin. In order to assess the effect of these human proteins on cell behavior, a mixed population of human lymphocytes and monocytes/macrophages was cultured over pre-coated SEVA-C surfaces. Through anti-CD3 and CD-14 monoclonal antibody labeling and cell counting, leukocyte adhesion onto pre-coated SEVA-C surfaces was analyzed. Based on the results, it was possible to detect albumin long-term effects and fibronectin short-term effects on cell adhesion proving that previously adsorbed proteins modulate leukocyte behavior.     

绿色建筑的市场之路

本文指出了绿色建筑市场化的重要性,通过列举绿色建筑特点分析了其市场化的可能性,结合实际案例充分展示了绿色建筑所具有的巨大经济效益和市场化潜力,最后结合笔者实际的工作经验,给出了实现绿色建筑市场化操作的四条原则性建议.     

Preliminary study on the adhesion and proliferation of human osteoblasts on starch-based scaffolds

Up to today, several techniques have been used to produce biodegradable porous scaffolds for tissue engineering. In this work, a new technique based on extrusion by using blowing agents in combination with a 50:50 (wt.%) blend of starch/cellulose acetate (SCA) was studied. The results show that by using this technique it was possible to obtain scaffolds with 70% of porosity and a fully interconnected network of pores, with sizes ranging from 200 to 500 μm. After their production, the mechanical properties of these scaffolds were tested, presenting a compressive modulus of 124.6±27.2 MPa and a compressive strength of 8.0±0.9 MPa. These values are within the best found in the literature and show that by using this technique, it is possible to produce scaffolds that, from a mechanical standpoint, may be suitable for bone tissue engineering. Cell culturing experiments showed that cells were viable and that there were no signs of cellular death after 3 weeks of culture. Finally, biochemical assays demonstrate that cells maintained the osteogenic phenotype throughout the experiment and deposition of mineralized extracellular matrix could be detected.     

Applications of experimental techniques to solid mechanics and materials science research in telecommunications and electronics

In the effort to support the rational development of reliable, manufacturable leading edge communications technologies, a broad variety of experimental mechanics and materials techniques have been developed and/or applied at the AT& Bell Laboratories in Murray Hill, NJ. Much of the emphasis in this paper is on the application of optical methods to the conduct of experimental mechanics and materials research relevant to the telecommunications and electronics industries. It will also describe the role such research plays in supporting the development of a new process or product.
This paper is based on a presentation at the BSSM/SEM International Conference on "Advances in engineering measurements" held at The University of Edinburgh, 30 August to 01 September 1994.     

绿色建筑技术在高等学校建筑的应用分析

高等学校校园建筑不同于一般的工业和民用建筑,是一个有机联系的整体,具有显著园区能耗的特点,绿色建筑技术在高等学校中有很好的利用前景.本文通过对3所高校建筑用能的分析,指出在照明、绿化和景观用水、洗浴用热水中采用绿色建筑技术,可有效的节约能源消耗.为高校开展节能减排、建设绿色校园提供参考.