大豆分离蛋白/淀粉可生物降解材料的性能研究

大豆分离蛋白(SPI)和淀粉混合物经丁二酸酐改性,经甘油和水增塑之后,热压得到力学性能较好的可生物降解材料。以材料的断裂伸长率和拉伸强度作为力学性能的考察指标,并利用FTIR对其进行了分析,结果表明:添加淀粉后,材料的力学性能有了很大提高,SPI与淀粉发生了Maillard反应,断裂伸长率为353%,拉伸强度为7.30MPa。     

多重改性大豆分离蛋白可降解材料性能研究

大豆分离蛋白(SPI)经四氢呋喃、乙酸锌、顺丁烯二酸酐多重改性后,用水和甘油增塑,然后经热压制得力学性能和抗水性能良好的可生物降解材料。研究了四氢呋喃、乙酸锌、顺丁烯二酸酐用量对SPI可生物降解材料力学性能、抗水性能的影响。结果表明:当改性剂四氢呋喃、乙酸锌、顺丁烯二酸酐的用量分别为大豆分离蛋白的267%、7%和15%时,SPI可降解材料的性能最佳,其断裂伸长率、拉伸强度、吸水率和耐水指数分别为187.12%、9.29 MPa、30.9%和0.48。     

增塑剂聚乙二醇(300)对大豆分离蛋白/玻纤复合材料性能的影响

采用大豆分离蛋白和玻纤作原料,并用聚乙二醇(300)进行增塑,采用传统的热压成型方法来制备大豆分离蛋白/玻纤复合材料。加入10份聚乙二醇(300),SPI/GF复合材料拉伸强度和吸水率降低,断裂伸长率和流动性则呈明显升高。     

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。     

复合改性大豆分离蛋白可生物降解材料的性能研究

采用微波辐射和马来酸酐(MA)接枝技术对大豆分离蛋白(SPI)进行了复合改性,产物经甘油和水增塑后,通过热压成型得到一种SPI可生物降解材料。研究了微波功率、微波处理时间和MA添加量对该改性材料的力学性能、耐水性能和光学性能的影响,并利用扫描电镜(SEM)观察了材料的微观结构。结果表明:该复合改性SPI可生物降解材料,呈现较好的微观网状结构,并具有良好的综合性能。其拉伸强度为11.48 MPa,断裂伸长率为240.3%,吸水率为33.4%,透光率为39.5%。     

短碳纤维的分散性与CFRC复合材料的力学性能

碳纤维增强水泥基复合材料(CFRC)是新发展起来的一种功能材料,制备CFRC复合材料过程中,碳纤维在水泥基体中的分散性直接影响CFRC复合材料的力学性能。借助超声波和分散剂羟乙基纤维素(HEC),实现了短碳纤维在水泥基体中的均匀分散。对所制备的CFRC复合材料的断口形貌,作了SEM观察和能谱分析;测试了试件的抗压强度和抗折强度。结果发现,水灰质量比为0.44,碳纤维均匀分散,其质量掺量为0.6%时,复合材料的抗压强度可提高20%,抗折强度提高129%。     

基于大豆蛋白的高回弹聚氨酯泡沫塑料的制备及性能研究

以大豆分离蛋白、高活性聚醚、聚合物多元醇、交联剂、发泡剂、泡沫稳定剂和混合异氰酸酯为原料,自由发泡、常温熟化制备了大豆蛋白基高回弹聚氨酯软泡。研究了大豆蛋白质(SPI)对聚氨酯泡沫物理性能、力学性能、孔结构和热性能的影响。结果表明:SPI添加量对泡沫物理和力学性能影响最大。随着SPI含量增加,泡沫的密度、尺寸稳定性提高,压陷硬度和舒适因子提高增大;回弹率下降,断裂伸长率减小,而拉伸强度先增大后减小。SPI能够提高聚氨酯的热稳定性,但最好低于150℃使用。     

硬脂酸钙对大豆分离蛋白塑料结构和性能的影响

将硬脂酸钙（CaSt2）与大豆分离蛋白（SPI）以不同比例混合,丙三醇作为增塑剂,经过涂膜的方式制备了改性SPI薄膜。通过衰减全反射-傅里叶变换红外光谱、X射线衍射、热分析、力学性能测试和水蒸气透过率系数等表征手段,研究了CaSt2改性SPI薄膜的结构和性能。结果表明,CaSt2在SPI中以两种结构形式存在,其中离子形式为主。与纯SPI薄膜相比,改性SPI薄膜的结晶度提高了70.4 %,内部结构更加致密。热分析表明,改性SPI薄膜的热稳定性增强。随着CaSt2含量的增加,改性SPI薄膜的水蒸气透过系数下降,当其含量为12 %时,水蒸气阻透能力提高了40 %;同时,断裂伸长率提高了67.63 %。     

谷氨酰胺转移酶处理对大豆分离蛋白、酪蛋白酸钠和明胶可食膜特性的影响

研究了谷氨酰胺转移酶(TGase)对大豆分离蛋白(SPI1和SPI2)、酪蛋白酸钠(NaCN1和NaCN2)及明胶(G1和G2)3类蛋白质成膜特性的影响。研究表明在成膜溶液中加入TGase(8U/g蛋白),可以使SPI、NaCN和明胶等3类蛋白质膜的抗拉强度和表面疏水性有不同程度的改善,其中抗拉强度增加的辐度为13.1%(P≤0.05),而表面疏水性增加的辐度为2%～216%(P≤0.05);明显降低了膜的水分含量、总可溶性物量及透光率。对于断裂伸长率,TGase的处理使G1膜、NaCN2膜、G2膜、NaCN1膜和SPI2膜分别增加16.3%、16.8%、43.0%、72.6%和440.5%,而使SPI1膜降低7.5%。SDS-PAGE电泳分析表明TGase使这3类蛋白质均产生了共价交联。     

PAPI改性大豆蛋白复合材料的制备与性能研究

以大豆分离蛋白（SPI）和多亚甲基多苯基异氰酸酯（PAPI）为原料,制备了改性大豆蛋白,再加入聚己内酯（PCL）,经过模压成型制备了改性大豆蛋白复合材料,并对其力学性能、微观结构和热性能进行了表征。结果表明,随着PAPI的加入,材料的力学性能得到很大程度的改善,拉伸强度由9.65 MPa上升到32 MPa,冲击强度由1.36 kJ/m2提高到11.7 kJ/m2;随着PAPI的加入,大豆蛋白材料的吸水性也有明显的改善,24 h吸水率从33.89 %下降到9.77 %;红外光谱分析表明,PAPI可以与大豆分离蛋白发生反应,改变了大豆蛋白的结构,并影响其性能,使复合材料内部结构更加致密。     

Structure and mechanical properties of cellulose derivatives/soy protein isolate blends

Biodegradable and biocompatible composites based on soy protein isolate (SPI) and various cellulose derivatives have been prepared, and the dependence of structures and mechanical properties on the content and species of cellulose derivatives for the composites were investigated by X‐ray diffraction, differential scanning calorimetry, scanning electron microscope, and tensile test. The selected cellulose derivatives, such as methyl cellulose (MC), hydroxyethyl cellulose (HEC), and hydroxypropyl cellulose, were miscible with SPI when the content of cellulose derivatives was low, and then the isolated crystalline domains, shown as the structures of network and great aggregate, formed with an increase of cellulose derivative content. The miscible blends could produce the higher strength, and even result in the simultaneous enhancement of strength and elongation for the HEC/SPI and MC/SPI blends. Meanwhile, the moderate content of great MC domains also reinforced the materials. However, the damage of original ordered structure in SPI gave the decreased modulus. Since all the components, i.e., cellulose derivatives and soy protein, are biocompatible, the resultant composites are not only used as environment‐friendly material, but the biomedical application can be expected, especially for the tissue engineering scaffold. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Transforming chromium containing collagen wastes into flexible composite sheets using cellulose derivatives: Structural,thermal, and mechanical investigations

Leather, footwear, and clothing industries produce significant quantity of chromium containing proteinaceous wastes. One of the major uses of these wastes is to convert them into sheets or boards. However, the previous methods could not provide flexible sheets with desired strength. Here, we describe a simple and efficient method for the preparation of flexible composite sheets using chromium containing collagenous wastes (CS) with the use of cellulose derivatives. The leather wastes have been partially hydrolyzed and converted into composite sheets under microwaves with the addition of 2‐hydroxyethyl cellulose (HEC) in varying concentrations from 2.5 to 20 wt%. A comprehensive strength as high as 3.14 ± 0.45 MPa with a softness of 3.8 ± 0.2 mm is achieved with the addition of 20 wt% HEC in the CS/HEC composite sheets. Scanning electron microscopic and mercury intrusion porosimetric analysis demonstrate the reduction in pores, especially micro pores (<50 μm), when the concentration of HEC is higher thereby showing improved interfacial adhesion of HEC onto CS. Infrared spectroscopy result indicates the presence of distinctive bands associated with both CS and HEC. There is also a reasonable increase in the thermal stability of the CS/HEC sheets as the content of HEC increases. Hence, the developed CS/HEC composite sheets were found to be flexible and have improved thermo‐mechanical properties, which are suitable for applications in leather product and allied industries. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers     

Morphology and properties of soy protein plastics modified with chitin

A series of bioplastics from isolated soy protein (SPI) and chitin (CH) was prepared with glycerol as a plasticizer by blending and compression molding. Their morphology and properties were investigated by wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamical mechanical thermal analysis (DMTA), scanning electron microscopy (SEM), and tensile and water‐absorption tests. The added CH as a filler cannot strongly interact with SPI molecules and, hence, this results in phase separation in blends. However, the rigid nature of the CH molecules enhanced the tensile strength and Young's modulus, but decreased the breaking elongation of the materials. When the CH content was higher than 10 wt %, the water absorption of the blends were obviously lower than that of the sheets without CH, resulting from the formation of a CH framework in the blends. Both soy protein and CH exhibit good biodegradability, biocompatibility, and bioactivity, and their composites may become a promising biomaterial. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3676–3682, 2003     

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     

细菌纤维素/热塑性聚氨酯复合气凝胶纤维制备及性能

使用绿色有机材料细菌纤维素(BC),并掺杂增强材料热塑性聚氨酯弹性体(TPU)经过湿法纺丝制备复合气凝胶纤维,通过傅里叶变换红外光谱(FTIR)、X射线衍射光谱(XRD)、热重分析(TG)、扫描电子显微镜(SEM)、全自动比表面孔隙度分析仪和单丝强力仪对制备的气凝胶纤维进行结构分析和性能表征,结果表明复合气凝胶纤维具有多孔结构,良好的力学性能和隔热性能,断裂强度达到24.69Mpa,断裂伸长为38.54%。     

大豆蛋白/亚麻复合材料的制备及性能研究

针对大豆蛋白塑料力学性能较差的问题,采用化学、填充的方法制备大豆蛋白与亚麻复合材料。通过扫描电子显微镜、电子万能试验机、熔体流动速率仪等实验仪器研究复合材料的形态结构、力学性能和流变性能,并测定了复合材料吸水率。研究结果表明,添加亚麻纤维对大豆蛋白的增强增韧效果都比较显著,硬度和拉伸强度对比纯大豆蛋白材料有了很大的提高,并且得到了大豆蛋白/亚麻复合材料的最佳用量,当亚麻的用量为6份时,复合材料的拉伸强度和硬度达到最佳,复合材料吸水率也较改性前有了很大的改善。     

Soy protein isolate/kraft lignin composites compatibilized with methylene diphenyl diisocyanate

Methylene diphenyl diisocyanate (MDI) was used to compatibilize kraft lignin (KL)/soy protein isolate (SPI) blends. The structure and properties of the resultant composite materials were investigated with wide‐angle X‐ray diffraction, differential scanning calorimetry, dynamical mechanical thermal analysis, scanning electron microscopy, and tensile and water absorption tests. The results indicated that graft copolymerization and a moderate degree of crosslinking between KL and SPI occurred in the composites because of the compatibilization of MDI, which favored the strengthening of the materials. Interestingly, the addition of 2 parts of MDI caused a simultaneous enhancement of the modulus, strength, and elongation of KL/SPI blends. The structure with grafting and moderate crosslinks reduced the water absorption of the materials. However, the excess crosslinks hindered the interaction between KL and SPI, resulting in a reduction of the mechanical properties. Scanning electron microscopy showed that the domains of the graft copolymer and crosslinking enrichment existed in the blends. When the MDI content was relatively low, these domains became concentric points of stress, enhancing the mechanical properties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 624–629, 2004     

Facile preparation for gelatin/hydroxyethyl cellulose-SiO2 composite aerogel with good mechanical strength,heat insulation,and water resistance

The advanced thermal insulation materials with low cost and high mechanical properties play an important role in transport packaging and thermal protection fields. An inorganic/organic composite aerogel was prepared through hydrogen bonds and chemical crosslinking among silica aerogel particles, gelatin (GA), and hydroxyethyl cellulose (HEC). The as-prepared GA/HEC-SiO₂ composite aerogels were characterized by compression tests, scanning electron microscopy, Fourier transform infrared, thermogravimetric analyzer, and contact angle tests to investigate the chemical composition and physical structure. The GA/HEC-SiO₂ composite aerogels exhibited a strong mechanical strength (0.53–4.01 MPa), a high compression modulus (1.33–11.52 MPa), a lower volume density (0.035–0.081 g/cm³), thermal conductivity as low as 0.035 W/[m K]), a porosity of more than 93%, and hydrophobic angle as high as 150.01° after hydrophobic modification. These results indicate that biopolymer composite aerogels embedded with SiO₂ aerogel particles display a bright future in thermal insulation.     

Effects of the molecular weight on the properties of thermoplastics prepared from soy protein isolate

Commercial soy protein isolate (SPI) was fractionated into four fractions by an acidifying method from pH 5.7 to 4.5 with 2M HCl. A mixture of SPI with glycerin (50 g/100 g of dry SPI) was compression‐molded to obtain thermoplastic sheets. The weight‐average molecular weight (M_w) of the fractions, the structure, and the mechanical properties of the thermoplastic SPI sheets were investigated with light scattering, IR spectroscopy, wide X‐ray diffraction patterns, differential scanning calorimetry, ultraviolet spectroscopy, scanning electron microscopy, and tensile testing. After heating compression, the SPI sheets were transparent and exhibited a smooth and homogeneous structure. Moreover, the crystallinity degree of the thermoplastic SPI was obviously higher than that of the premix before compression because of the formation of intermolecular hydrogen bonding. The M_w's of the fractions were 1.17 × 10⁵ to 3.21 × 10⁵, and they increased with increasing pH value in fractionation. The mechanical properties and water resistance (R) of the SPI sheets increased with increasing M_w of the SPI fractions. The tensile strength and breaking elongation of the SPI sheets with an M_w value of 3.21 ×10⁵ were 5.7 MPa and 135%, respectively, and the R value was 0.54 after immersion in water for 15 days. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 3373–3380, 2001     

改性纤维素和壳聚糖共混膜的制备及性能研究

将水溶性的纤维素衍生物——羟乙基纤维素与壳聚糖乙酸水溶液用溶液浇铸法制得羟乙基纤维素/壳聚糖(HEC/CS)共混膜。确定了该共混膜的最佳制备条件,并测试了其力学性能和生物降解性能。结果表明:HEC/CS共混膜具有好的抗菌性。