甲基丙烯酸缩水甘油酯接枝聚烯烃及在塑料改性中的应用进展

简单介绍了甲基丙烯酸缩水甘油酯熔融接枝聚烯烃的第二单体、引发剂、反应温度和反应时间等因素对接枝反应的影响,探讨了接枝率的测定方法及接枝聚烯烃在塑料改性中的应用等。     

SPI改性煤和氧化煤的生物降解研究

以大豆分离蛋白质（SPI）为改性剂，用吸附和接枝的方法对神府煤及神府氧化煤进行了表面改性和生物降解研究，用FTIR对接枝改性煤进行了表征，用从土壤中分离的混合微生物菌种，对煤及SPI改性煤和氧化煤进行了好氧生物降解实验，以生物降解产生的CO2产率、试样的最终失重率、降解残煤的FTIR分析、腐植酸含量测定和降解残液的UV-VIS光谱表征了生物降解效果，结果表明，SPI改性对煤和氧化煤的微生物降解有促进作用，尤其是对氧化煤促进作用更明显，接枝改性的促进作用比吸附改性强，并且，由于接枝改性扣吸附改性中SPI与煤的界面相互作用不同，从而导致他们具有不同的生物降解机理。     

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。     

聚丙烯塑料的改性研究

概述了目前广泛采用的聚丙烯塑料的改性方法研究,包括聚丙烯塑料的共聚、接枝、交联等化学改性以及共混、增强、填充等物理改性方法.     

GMA接枝聚烯烃及在塑料改性中的应用进展

简单介绍了甲基丙烯酸缩水甘油酯(GMA)熔融接枝聚烯烃的第二单体、引发剂、反应温度和反应时间等因素对接枝反应的影响,接枝率的测定方法及接枝聚烯烃在塑料改性中的应用等。     

甲基丙烯酸缩水甘油酯的合成研究

采用二步法合成了甲基丙烯酸缩水甘油酯,研究了第一步反应过程4种溶剂对甲基丙烯酸钠盐形成的影响,探讨了第二步反应过程不同相转移催化剂、反应温度及所合成钠盐中碱过量比率与产物收率的关系,对最后产物进行了分析和表征。结果表明,合成反应第一步可使用水为溶剂,碱过量10%,第二步反应中,使用三乙基苄基氯化铵为催化剂,控制反应温度105℃～110℃,反应3.0h,可使GMA收率达到80.5%。     

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.     

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。     

甲基丙烯酸缩水甘油酯的合成研究

在相转移催化剂季铵盐和阻聚剂对苯二酚存在下 ,采用二步法由甲基丙烯酸 (MAA)和环氧氯丙烷(ECH)合成了甲基丙烯酸缩水甘油酯 (GMA)。通过正交实验确定了最佳反应条件 :物料配比n(甲基丙烯酸钠 )∶n(环氧氯丙烷 ) =1∶8,反应温度 10 5℃ ,反应时间 4h ,催化剂选用十六烷基三甲基溴化铵。在该工艺条件下 ,产品产率为 94 73% ,纯度为 96 80 %。     

神府煤对大豆分离蛋白质的吸附特性研究

采用静态吸附法探讨了神府煤粉(SFC)对大豆分离蛋白质(SPI)的吸附特性。研究了SPI溶液初始质量浓度(3.0—12.0 kg/m3)、温度(20、30、40、50℃)、pH值(4.0—9.0)等条件对吸附量的影响。结果表明,吸附平衡时间为12 h,适宜的pH值为6.0。SFC对SPI吸附过程为非自发的放热过程,吸附过程符合二级动力学模型。红外光谱分析表明,蛋白质分子主要通过C O和NH与煤大分子结构中的OH和C O对应形成2个活性位点的氢键作用,吸附于煤表面。     

Properties of molded soy protein isolate plastics

Thermal property of soy protein isolates (SPI) was studied with differential scanning calorimetry and thermogravimetric analysis. The weight loss of pure SPI is about 300°C. The glass transition temperature (T_g) is above 200°C. The best molding temperature of glycerin plasticized SPI plastics were then given. It is between 125 and 140°C. Subsequently the special property of molded SPI plastics was investigated. Results show that the atmosphere humidity affects the mechanical property and thermal property of SPI plastics. With the increasing humidity, the tensile strength decreases. While the elongation at breakage and peak area of the differential scanning calorimetry curve increases. At high temperature even at 140°C the molding temperature SPI plastics still have tensile strength though it decreases with the increasing test temperature while elongation at breakage increases. Dynamic mechanic thermal analysis test show that the storage modulus decreases with the rising temperature. The mechanical loss peak appears at lower temperature with the increasing amount of glycerin content. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Graft polymerization of styrene on soy protein isolate

The grafting of styrene on soy protein isolate (SPI) in an 8 moL/L urea aqueous solution initiated by ammonium cerous nitrate and potassium persulfate was studied. The grafted copolymers were characterized by IR spectroscopy and DSC. The results indicated that styrene was grafted on the SPI. The influence of the reaction conditions on the grafting and efficiency percentages was investigated. The grafting and efficiency percentages initially increased and then decreased with the increase of the initiator concentration, monomer concentration, and reaction temperature. With the increase of reaction time, the grafting and efficiency percentages increased. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1457–1461, 2005     

Preparation of soy protein concentrate and isolate from extruded-expelled soybean meals

Soy protein concentrates (SPC) and soy protein isolates (SPI) were produced from hexane-defatted soy white flakes and from two extruded-expelled (EE) soy protein meals with different degrees of protein denaturation. Processing characteristics, such as yield and protein content, and the key protein functional properties of the products were investigated. Both acid-and alcohol-washed SPC from the two EE meals had higher yields but lower protein contents than that from white flakes. Generally, SPC from an acid wash had much better functional properties than those from an alcohol wash. The SPI yield was highly proportional to the protein dispersibility index (PDI) of the starting material, so the EE meal with lower PDI had lower SPI recovery. The protein content in SPI prepared from EE meals was about 80%, which was lower than from white flakes. Nevertheless, SPI from EE meals showed functional properties similar to or better than those from white flakes. The low protein contents in SPC and SPI made from EE meals were mainly due to the presence of residual oil in the final products. SPI made from EE meals had higher concentration of glycinin relative to β-conglycinin than that from white flakes.     

Properties of fibers produced from soy protein isolate by extrusion and wet-spinning

Fibers were produced from soy protein isolate by both wet-spinning and extrusion. In the wet-spinning process, aged, alkaline protein solution was forced through a spinnerette into an acid coagulating bath. In the extrusion process, a twinscrew extruder forced a protein isolate-water mixture through a die. The physical properties of the fibers were measured at various water activities. The fibers produced by both methods were brittle and lacked tensile strength (tenacity). The addition of glycerol reduced brittleness in extruded fibers. Zinc and calcium ions decreased the brittleness of wet-spun fibers. The tenacity of soy fibers was significantly improved by post-spinning treatments, including acetic anhydride, acetaldehyde, glyoxal, glutaraldehyde, a combination of glutaraldehyde and acetic anhydride, and stretching. The best extruded fibers were produced with a mixture of 45% soy protein, 15% glycerol, and 40% water, finished with a combination of glutaraldehyde and acetic anhydride and then stretched to 150% their original lengths. The best wet-spun fibers were produced with a 19.61% soy protein suspension at pH 12.1; coagulated in a 4% hydrochloric acid solution that contained 3.3% sodium chloride, 3.3% zinc chloride, and 3.3% calcium chloride; and followed by treatment with 25% glutaraldehyde and stretching to 170% their original lengths.     

Effects of nanoscale hydroxypropyl lignin on properties of soy protein plastics

For the first time, soy protein isolate (SPI)/hydroxypropyl alkaline lignin (HPL) composites have been successfully prepared by mixing them in aqueous solution containing a small amount of glutaraldehyde as compatibilizer, and then compression‐molded to obtain plastic sheets. The structures of the SPI/HPL composites were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, and scanning electron microscopy, indicating the existence of amorphous networks and nanoscale HPL dispersion in the SPI matrix. When HPL content was lower than 6 wt %, the HPL‐domain occurred in SPI/HPL composites with a dimension of about 50 nm, indicating a high interfacial activity. Differential scanning calorimetry analysis showed that the glass transition temperature of the SPI/HPL sheets increased from 62.5 to 70.4°C with an increase of HPL content from 0 to 6 wt %. Moreover, the tensile strength of the SPI/HPL nanocomposite sheets with 6 wt % HPL and 3.3 wt % glutaraldehyde was enhanced from 8.4 to 23.1 MPa compared with that of the SPI sheets, suggesting that the nanoscale HPL dispersion significantly reinforced the SPI materials. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 334–341, 2006     

Effect of lipids on soy protein isolate solubility

Reduced-lipid soy protein isolate (SPI), prepared from soy flour treated so that most of the polar lipids have been removed, exhibited an increase in protein solubility of 50% over that of the control SPI prepared from hexane-defatted flour. Adding lipids from a commercial SPI during processing of reduced-lipid SPI decreased SPI solubility by 46%. The 19% decreased solubility caused by the lipids (primarily phospholipids) was largely recovered by treating the protein with a reducing agent (2-mercaptoethanol). The balance of protein insolubility, caused by the lipids, was attributed to a smaller lipid fraction (approximately 5% of the total lipids). Adding lipids during SPI processing contributed to both the formation of oxidized protein sulfhydryls, incapable of being reduced by 2-mercaptoethanol, and to oxidative deterioration of protein as determined by protein carbonyl contents.     

PVAc乳胶/改性大豆分离蛋白共混胶黏剂的制备及性能

针对大豆蛋白胶黏剂耐水性差的缺点,用尿素初步改性大豆分离蛋白（SPI）,然后与白乳胶（PVAc）共混合成了共混改性大豆分离蛋白胶黏剂。采用正交实验方法考察了大豆蛋白胶与白乳胶质量比、共混时间、交联剂质量分数、交联时间对大豆蛋白胶黏剂剪切粘接强度的影响,确定了优化配比及制备工艺条件,并在此基础上采用正交试验优化了热压参数。结果表明：大豆蛋白胶与白乳胶质量比10∶1,共混时间1h,交联剂质量分数1.0%,交联时间1.5h,热压温度120℃,热压压强1.2MPa,热压时间2min/mm,涂胶量250g/m2时,测得胶黏剂的干态剪切粘接强度为2.01MPa,按照Ⅰ类胶合板标准测得湿态剪切粘接强度为1.04MPa,并对优化配方进行了结构与性能分析。     

Hydrogel films and microcapsules based on soy protein isolate combined with alginate

Alginate hydrogels are combined with soy protein isolate (SPI), a plant derived protein with low immunogenicity, appropriate biodegradability and low cost, to produce biocompatible films, and microcapsules. The cell–material interaction is assessed through the use of mouse embryotic fibroblast cells (MEF cells) on films, and the results illustrate that the alginate/SPI hydrogel films support cell attachment, spreading, and proliferation. Cell biology results combined with degradation studies suggest that such hydrogels are promising biomaterials for soft tissue regeneration or as wound dressing materials. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44358.     

Surface modification of poly (ethylene terephthalate) fabric by soy protein isolate hydrogel for wound dressing application

In this study, a composite of poly (ethylene terephthalate) (PET) fabric and soy protein isolate (SPI) hydrogel loaded with gabapentin was developed. For covalent attachment of SPI on the surface of PET fabric, graft polymerization of acrylic acid (AA) on the surface of PET fabric was performed and then carboxyl groups available in the structure of AA were activated using EDAC and then SPI was coated on the surface of PET fabric. The results revealed appropriate connection between hydrogel and modified fabric. The hydrogel was characterized by swelling test and the drug release behavior was investigated. It was found that the casting temperature affects the swelling ratio of the hydrogel and an appropriate release profile of the drug was observed. The surface of fabric was characterized by contact angle measurement, electron microscopy, and infrared spectroscopy. In vitro cell culture study was performed using NIH 3T3 mouse fibroblasts to investigate the biocompatibility of final composite and MTS results along with morphology of cells on the surface of PET fabric coated with SPI revealed the biocompatibility of final product and no cell cytotoxicity was observed in modified PET fabric.