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完全生物降解塑料发展现状 总被引:6,自引:0,他引:6
本文着重论述了国外完全生物降解塑料的发展状况,指出只有开发完全降解的塑料才是真正减少塑料垃圾及减轻环境污染的有效途径。结合我国国情,讨论了在我国进行开发以淀粉为原料的完全降解塑料的可行性,初步给出了一个开发我国生物降解塑料的可能的方向。 相似文献
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本文从生物降解塑料定义及应用出发,进行了生物降解塑料发展及与环境保护关系的论述,对我国生物降解塑料行业的发展及生物降解塑料发展所面临的机遇和执战做出了综述,并对其未来发展做了展望。 相似文献
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NOVON塑料是美国NOVONINTERNA TIONAL公司的自然降解塑料技术的产品之一 ,在日本及亚洲市场 ,由日本公司总代理。随着人们环境意识的提高 ,降解塑料已成当前一个热门话题。降解塑料中有光降解、生物降解以及光、生物降解等几个大类 ,其中生物降解的推广应用 ,对改善废弃塑料对环境的影响十分有利 ,因此成为开发研究的一个重点品种。生物降解塑料中有可完全降解的特种聚酯类 (如PHB、PHV及其共聚物PHBV ,聚乳酸、聚已内酯等 )与掺混型二个大类。前者降解性能很好 ,但价格昂贵 ,生产、应用受到限制 ;后者由… 相似文献
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淀粉基生物降解塑料的研究现状和发展方向 总被引:1,自引:0,他引:1
传统塑料如聚乙烯很难在自然环境中降解,淀粉基生物降解塑料由于在微生物作用下很容易降解,转化微低分子量产物,不会带来环境问题。目前所面临的挑战是,能否生产出机械性能优异、能完全生物降解和成本较低的淀粉基生物降解塑料。本文综述了淀粉基塑料的研究历程和在包装领域种的若干进展,同时对近期最有可能实现产业化的方向做了简要的阐述。 相似文献
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Spherical void expansion in plastics and rubber-modified plastics is investigated under radial traction conditions. The plastics
are modeled as elastic-plastic pressure-sensitive materials and the rubbers are modeled as nonlinearly elastic materials.
First, the growth of a spherical void in an infinite plastic matrix is investigated under remote radial traction conditions.
The results show that the cavitation stress of the plastic decreases significantly as the pressure sensitivity increases.
Then, the growth of a spherical void located at the center of a spherical rubber particle in an infinite plastic matrix is
investigated under remote radial traction conditions. The results indicate that without any failure criteria for the rubber,
the cavitation stress does not exist when the void is small and the rubber is characterized by high-order strain energy functions.
However, when a failure criterion for the rubber is considered at a finite stretch ratio, the results show that the cavitation
stress for the plastic with the rubber particle becomes close to that for the plastic without the rubber particle.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Nonlinear finite element analysis of reinforced concrete beams strengthened by fiber-reinforced plastics 总被引:2,自引:0,他引:2
Numerical analyses are performed using the ABAQUS finite element program to predict the ultimate loading capacity of rectangular reinforced concrete beams strengthened by fiber-reinforced plastics applied at the bottom or on both sides of these beams. Nonlinear material behavior, as it relates to steel reinforcing bars, plain concrete, and fiber-reinforced plastics is simulated using appropriate constitutive models. The influences of fiber orientation, beam length and reinforcement ratios on the ultimate strength of the beams are investigated. It has been shown that the use of fiber-reinforced plastics can significantly increase the stiffnesses as well as the ultimate strengths of reinforced concrete beams. In addition, with the same fiber-reinforced plastics layer numbers, the ultimate strengths of beams strengthened by fiber-reinforced plastics at the bottom of the beams are much higher than those strengthened by fiber-reinforced plastics on both sides of the beams. 相似文献
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塑料加工成型技术的最新研究进展 总被引:1,自引:0,他引:1
依据塑料工业发展低耗、高效、环保型“绿色”加工成型技术的重大需求,随着塑料塑化输运方法的不断演变与创新,在塑料动态加工成型方法和设备的基础上提出和研究了基于拉伸流变的塑料加工成型方法和技术,着重讨论了拉伸形变支配的叶片挤压系统中塑料塑化输运过程、叶片挤压系统的技术特征和叶片塑化输运技术的应用。研究结果表明,与传统技术及设备相比较,这种新技术及设备具有加工历程缩短50 %以上、加工能耗降低30 %左右、混合混炼效果好、制品质量提高、对物料适应性广等优异的技术性能。同时发现,新技术及设备在多相多组份复合材料、剪切热敏感高分子材料等物料体系的加工方面具有独特优势。 相似文献
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植物油基泡沫塑料环境友好,综述了植物油制备泡沫塑料的研究进展,主要介绍了植物油的基本组成,并根据泡沫基体材料组成对植物油基泡沫材料进行了分类,分析了植物油改性制备泡沫塑料的主要方法、种类、反应机理及其对材料性能的影响,展望了植物油基泡沫塑料的发展和应用方向。 相似文献
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C. Jördens M. Scheller S. Wietzke D. Romeike C. Jansen T. Zentgraf K. Wiesauer V. Reisecker M. Koch 《Composites Science and Technology》2010
We employ terahertz time-domain spectroscopy (THz TDS), a novel, non-destructive testing method, to study the fibre orientation and fibre content in reinforced plastics. The birefringent properties of plastics filled with differing amounts of short glass fibres are measured at frequencies from 100 GHz up to 1 THz. To predict the permittivity of the experimentally examined composite materials, we use an effective medium theory first introduced by Polder and van Santen. On the basis of the measured data and this model, we deduce the additive content ξ, the preferential orientation of the fibres φ and the fraction of orientated fibres a. Our findings agree well with corresponding mold flow simulations performed with commercially available software. 相似文献
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申开智 《高分子材料科学与工程》1993,9(3):113-119
建立了螺纹制品成型时的受力模型,指出由于收缩制件对型芯的正压力主要作用在型芯牙尖顶部及牙尖的一个侧面上,在型芯表面的其余部位压力基本为零,甚至在制品和型芯间存在有间隙。实验证实了上述假设的正确性。在此基础上推导出了新的脱模扭矩计算公式,公式表明,脱模扭矩的大小与塑料的弹性模量、泊松比、脱模时的收缩率、摩擦系数、塑件平均壁厚、螺纹牙尖角、螺牙高、扭径等因素有关。 用螺纹型芯可更换的试验模具,用多种塑料模制螺纹制品,实测其脱模扭矩证明了该公式的正确性 相似文献
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羊毛角蛋白塑料的制备和力学性能 总被引:1,自引:0,他引:1
利用羊毛制备了角蛋白塑料,考察了模压压强、模压温度以及增塑剂等对角蛋白塑料力学性能的影响。结果表明,随着模压压强的增大,塑料的最大拉伸强度升高,断裂伸长率降低。模压温度对塑料的力学性能影响不大。水和甘油都是角蛋白塑料良好的增塑剂,水含量为27%和甘油含量为20%时的增塑作用最好。 相似文献