可完全生物降解蛋白质塑料

本文对可生物降解的蛋白质及大豆蛋白质塑料的研究状况做了介绍，对蛋白质塑料的生物降解机理也进行了分析，同时对大豆蛋白质塑料的降解性进行了研究。     

可生物降解蛋白质塑料的改性研究进展

阐述了可生物降解材料的定义、特点及降解机理,论述了蛋白质塑料的研究概况,包括蛋白质降解材料的种类、发展历史和加工方法,综述了大豆蛋白塑料的改性研究进展。     

大豆蛋白质塑料加工和力学性能的研究

采用HAAKE扭矩流变仪研究了增塑型、还原剂和润滑剂等对大豆蛋白质塑料扭短流变性能的影响，并在此基础上，对经HAAKE密炼并模压制得的大豆蛋白质塑料力学性能作了测试。     

甲基丙烯酸缩水甘油酯对大豆蛋白塑料改性作用研究

用模压的方法制备了甲基丙烯酸缩水甘油酯(GMA)改性大豆分离蛋白质(SPI)塑料。表征了GMA改性SPI塑料的力学性能、耐水性,并分析了GMA与SPI之间的相互作用。结果表明GMA在模压过程中,环氧基与蛋白质分子间发生接枝和交联反应,同时自聚,在GMA含量较低时可以同时对SPI塑料起到增强和增塑作用,但是随着GMA含量增加,交联作用增强,塑料的断裂伸长率下降。     

提高蛋白质生物塑料力学性能的研究进展

蛋白质生物塑料力学性能差是影响其商业化的主要因素。本文介绍了提高蛋白质生物塑料力学性能的几种手段,即蛋白质失活、生物纤维增强、与合成/天然可降解高分子共混、纳米复合增强等4个方面对提高其性能的有效性。对影响蛋白质失活的主要因素,即改变环境pH值、添加尿素、无机盐及交联剂等做了详细分析。对多种天然植物纤维的增强效果以及如何增强植物纤维在聚合物基体中的分散性、与其相容性等分别做了介绍。对多种纳米材料,如纳米纤维素、层状硅酸盐、碳纳米管/石墨烯等的增强效果也做了介绍。最后提出今后发展方向为：①提高蛋白质生物塑料的性能可控性,即兼顾可生物降解性与提高力学性能、延长使用寿命;②高性能化研究,以使蛋白质生物塑料满足某些特殊要求;③拓展蛋白质新来源。     

碱和尿素改性大豆蛋白质塑料研究

大豆蛋白质塑料作为天然可再生高分子材料具有良好的发展前景。大豆蛋白质塑料加工性能和韧性很差,限制了其工业化生产和应用范围。本文通过碱和尿素改性大幅提高大豆蛋白塑料的流变性和韧性,无需添加增塑剂便具有了良好的加工性能和韧性。     

棉籽蛋白质塑料改性研究

以棉籽粕为原料,盐提酸沉的方法来制备棉籽蛋白质,将提取出的棉籽蛋白质与不同比例的马来酸酐和一定量甘油混合,经模压成型制得棉籽蛋白质塑料,并对其进行力学性能测试、吸水性测试、溶解性的测试和红外光谱分析。考察了加工条件对蛋白质塑料性能的影响,结果表明：马来酸酐的加入提高了蛋白质材料的断裂伸长率,同时显著降低了材料的吸水率。通过对加工条件的考察,得到了热压棉籽蛋白质塑料的最佳工艺条件：140℃,10 MPa下模压10 min。     

硬脂酸对大豆蛋白质塑料性能的影响

对水的敏感性是阻碍大豆蛋白质降解塑料广泛应用的不利因素,为了克服这一缺点,实验固定甘油和大豆蛋白质的比例,通过添加硬脂酸与大豆蛋白质共混,研究了其添加量对机械性能和吸水率的影响。同时拉伸和红外、扫描电镜等实验表明甘油、硬脂酸对膜的力学性能、吸水率、断面形态、红外图谱均有影响。     

大豆蛋白复合材料的研究进展

对国外近十年来大豆蛋白与聚磷酸盐、玻璃纤维、麦草、苎麻、淀粉、聚乙烯醇、聚己内酯、聚羟基酯醚等的复合材料的制备方法，材料性能特点进行了总结。分析了大豆蛋白复合材料作为可生物降解材料替代某些通用塑料和工程塑料的应用前景，并提出了近期的发展方向。     

蛋白质的改性和力学加工性能的研究

综观各种研究报道，力学性能较低和对水的敏感性是阻碍蛋白质基降解塑料广泛应用的不利因素，为了克服这一缺点，人们广泛探索了对蛋白质的各种改性和处理：热、碱改性、还原剂处理、交联剂改性、添加助剂改性、填充改性、等来改善力学加工性能，以期获得具有实用价值的蛋白质塑料。     

Thermal and mechanical properties of plastics molded from urea-modified soy protein isolates

Soy protein has been considered as a potential alternative of some petroleum polymers in the manufacture of plastics. The purpose of this investigation was to characterize the thermal and mechanical properties of plastics made from urea-modified soy protein. Soy protein isolate was separated from the defatted soy flour, modified with various urea concentrations, and compression-molded into plastics. Differential scanning calorimetry showed that the temperatures of denaturation and the enthalpies of denaturation of the modified soy protein decreased as urea concentrations increased above 1 M. At the same urea concentration, molded plastics made from the modified soy proteins showed a similar temperature of denaturation as the modified soy protein, but a lower enthalpy of denaturation. Tensile strength and Young's modulus of the molded plastics from the modified soy proteins increased as urea concentration increased and reached their maximum values at 8 M urea modification. Both storage modulus and glass transition temperature of the plastics from the modified soy proteins increased as urea concentration increased. The plastics made from the 2 M urea-modified soy proteins showed improvements in elongation, tough fracture behavior, and water resistance. The urea may function as a denaturant, a plasticizer, and a filler.     

Plasticization of soy protein polymer by polyol-based plasticizers

Soy protein isolate (SPI) was mixed with four polyol-based plasticizers and molded into plastics using a hot press. The plasticized SPI powder was evaluated for denaturation temperatures and denaturation enthalpies. The SPI plastics were studied for mechanical properties, glass transition temperatures, storage modulus, morphology, and water absorption. Thermal properties of the SPI plastics with propylene glycol were depressed to the largest degree, and the plastics with glycerol showed the largest strain at break, whereas plastics with 1,3-butanediol gave the highest tensile strength. The morphology of the fractured surface on the SPI plastics changed from brittle fracture for the unplasticized SPI to ductile fracture for the plasticized SPI. Water absorption of all the plasticized SPI plastics was lower than that of the unplasticized SPI plastics.     

蛋白质塑料改性研究进展

力学性能较低和对水敏感是阻碍蛋白质基降解塑料广泛应用的不利因素,为了克服这一缺点,人们广泛探索了对蛋白质的各种改性:热、碱改性、还原剂改性、交联剂改性、添加助剂改性、填充改性、酸改性等来改善力学加工性能,以期获得具有实用价值的蛋白质塑料。     

煤基蛋白质生物降解塑料的开发技术

介绍了煤基复合塑料以及煤的生物降解特性的发展概况，论述了煤与蛋白质聚合的方法及可行的接枝理论。分析发现，可以利用蛋白质中的氨基酸，使之与预处理后的煤发生反应形成多肽链接枝改性煤；或是发生酰基化反应将蛋白质接枝到煤中。接枝改性煤的氮含量有了一定的提高，而且还可能加速煤的生物降解，为煤基蛋白质生物降解塑料的发展提供了可能。     

Preparation and characterization of soy protein plastics plasticized with waterborne polyurethane

Utilizing anionic waterborne polyurethane (WPU) as a plasticizer, for the first time, we prepared new soy protein isolate (SPI) plastics. The WPU was prepared by using the emulsion‐extending‐chain method, and mixed with soy protein in aqueous dispersion. The mixture was cast, cured, pickled and hot‐pressed to form SPI plastics plasticized with WPU. The plastics sheets were characterized by infrared spectroscopy, scanning electron microscopy, ultraviolet spectrophotometry and wide‐angle X‐ray diffraction, and their properties were measured by using dynamic mechanical analysis, differential scanning calorimetry and tensile testing. The results revealed that SPI plastics plasticized with WPU possess good mechanical properties, such as a tensile strength (σ_b) of 7–19 MPa, water resistance (σ_b(wet)/σ_b(dry) = 0.4–0.5), optical transmittance and thermal stability, because of the good miscibility and strong interaction between WPU and SPI. With an increase of WPU content from 20 to 50 wt%, the elongation at break (ε_b) value of the sheets increased from 50 up to 150 %, and is much higher than that of the pure SPI sheet. WPU as a plasticizer can play an important role in improving the properties of SPI plastics. Copyright © 2004 Society of Chemical Industry     

关于蛋白质塑料的研究

近年来农业可再生材料受到人们的重视,蛋白质是可生物降解的环境友好材料。以不同农作物蛋白质来源分类介绍了国内外蛋白质塑料的研究进展,有大豆蛋白质、玉米蛋白质、向日葵蛋白质、小麦蛋白质、棉籽蛋白质及其他豆类蛋白质。涉及蛋白质材料的增塑、交联、共混等改性方法和压缩、挤出、注射等成型方法。     

Thermal and mechanical properties and water absorption of sodium dodecyl sulfate‐modified soy protein (11S)

The thermal and mechanical properties and water absorption of sodium dodecyl sulfate (SDS)‐modified 11S soy protein and molded plastics made from it were studied using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), mechanical tests, and scanning electron microscopy (SEM). The DSC results showed that both the temperature and enthalpy of thermal denaturation of modified 11S solutions decreased as the SDS concentration increased. Nonfreezing water of the modified 11S solution had a minimum value at 1.0% SDS. The ordered structure of SDS‐modified 11S protein was recovered and/or newly formed during the freeze‐drying process. Both DSC and DMA results showed that SDS was a plasticizer of 11S, and the glass transition temperature of modified 11S plastics decreased with increasing SDS concentration. Both the tensile strength and elongation of modified 11S plastics first decreased and then increased as the SDS concentration increased, and 5.0% SDS‐modified 11S plastic had the highest tensile strength and elongation. The SEM observations supported these results. A water‐absorption test showed a reduction in the water resistance of 11S plastics after SDS modification. The rate of water absorption increased with increasing SDS concentration. The hydrophobic interaction between SDS molecules and 11S protein was found to have important effects on the thermal and mechanical properties and the water absorption of 11S plastics. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 166–175, 2001     

Thermal and mechanical properties and water absorption of guanidine hydrochloride‐modified soy protein (11s)

Thermal and mechanical properties and water absorption of guanidine hydrochloride (GuHCl)‐modified 11S soy protein and molded plastics made from it were studied using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), mechanical tests, and scanning electron microscopy (SEM). The DSC results showed that the denaturation temperature of GuHCl‐modified 11S solutions was higher than that of the control sample and the high concentration GuHCl completely denatured 11S. Nonfreezing water of the modified 11S solution exhibited a minimum value at 0.9M GuHCl. Both DSC and DMA results showed that GuHCl was a plasticizer of 11S and the glass transition temperature of modified 11S plastics decreased with increasing GuHCl concentration. Both the stress and strain of modified 11S plastics reached their highest values at a 0.9 GuHCl concentration. The SEM observations supported these results. A water‐absorption test showed an improvement in the water resistance of 11S plastics with GuHCl modification. The water absorption had a minimum value at 0.9M GuHCl. The interaction between GuHCl molecules and 11S protein was found to have important effects on the thermal and mechanical properties and the water absorption of 11S plastics. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1063–1070, 2000