GMA原位改性炭黑对NR胶料性能的影响

研究甲基丙烯酸缩水甘油酯(GMA)原位改性炭黑N220对NR胶料性能的影响。结果表明，GMA不仅与炭黑发生接枝反应，而且与NR共交联，增强了炭黑与NR的结合GMA改性炭黑使NR混炼胶的门尼粘度减小和t90延长，硫化胶的强伸性能、耐热老化性能和耐屈挠龟裂性能提高；GMA用量为5份时硫化胶综合性能较好。     

填料填充UHMWPE交联塑料磨粒磨损性能研究

本文采用二氧化硅、炭黑和还原铁粉三种填料对UHMWPE交联体系进行填充改性,采用模压烧结成型法制备了改性UHMWPE交联塑料,实验结果表明:三种填料对磨损率的影响比较一致,当二氧化硅含量6%、炭黑含量8%、还原铁粉含量2%时,磨粒磨损率最小。在磨粒磨损实验中,还原铁粉的含量对磨粒磨损率的影响最大。     

甲基丙烯酸缩水甘油酯增强EPDM的力学性能和交联密度

研究了甲基丙烯酸缩水甘油酯(GMA)／三元乙丙橡胶(EPDM)硫化胶的力学性能。结果表明,GMA具有明显的增强效果。GMA对EPDM的增强作用与GMA参与了橡胶的接枝和交联反应有关。     

大豆分离蛋白/聚乙烯醇塑料的制备及性能研究

将聚乙烯醇（PVA）按不同比例与大豆分离蛋白(SPI)混合,采用丙三醇作为增塑剂,经模压成型制备SPI/PVA塑料,采用X射线衍射仪、动态热机械分析仪、差示扫描量热仪、万能电子拉力试验机、扫描电子显微镜等研究了SPI/PVA塑料的结构、形态和性能。结果表明,丙三醇增塑的SPI会出现微相分离,即出现富丙三醇微区和富蛋白微区,而PVA的加入主要破坏了SPI在富丙三醇微区的晶体结构,并使富丙三醇微区的玻璃化转变温度向高温方向偏移。PVA的加入还明显提高了SPI/PVA塑料的拉伸强度,当PVA含量为1份时,其拉伸强度比纯SPI塑料提高了41.5 %;PVA的加入对SPI/PVA塑料的吸水性也有明显改善,其24 h吸水率从134.86 %下降到77.38 %。     

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 %。     

茂金属聚乙烯的过氧化交联

以过氧化二异丙苯(DCP)为交联刑,通过开炼、模压成型对茂金属聚乙烯(MPE)进行过氧化交联改性.得出MPE的交联度随交联剂用量、模压时间和模压温度的升高而升高.但随着交联度的上升,拉伸强度先升后降.研究表明:拉伸强度的变化是交联度和结晶度变化共同作用的结果.加入抗氧剂后,MPE的热老化性能得到明显的改善.     

不同成型方式下UHMWPE耐热改性进展

介绍了近年来超高分子量聚乙烯(UHMWPE)在模压成型、挤出成型、注塑成型方面的耐热改性研究进展,分析了采用不同成型方法对UHMWPE耐热改性的方法及改性效果。关于UHMWPE模压与挤出成型的耐热改性方法主要包括物理改性(填充改性、共混改性、共混填充改性)、化学改性(过氧化物交联、偶联剂交联、辐射交联)、聚合填充复合改性,而UHMWPE的注塑成型耐热改性研究较少。对UHMWPE进行耐热改性,加入的改性材料后,能显著提高复合材料耐热性,但是,部分材料的加入却降低了UHMWPE耐磨性、抗冲击性等性能,需要对UHMWPE注塑成型的耐热改性及改性材料的选用进一步研究。最后,对UHMWPE的耐热改性的发展趋势进行了展望。     

改性炭黑增强三元乙丙橡胶的力学性能与加工性能

研究了用甲基丙烯酸缩水甘油酯(GMA)、甲基丙烯酸-2-羟乙酯(HEMA)和N-羟甲基丙烯酰胺(NMA)3种单体改性炭黑增强三元乙丙橡胶(EPDM)的力学性能,并用橡胶加工分析仪分析了GMA、HEMA和NMA改性炭黑对EPDM未硫化胶的加工性能。结果表明,GMA、HEMA和NMA改性炭黑均改善了EPDM硫化胶的力学性能,当其用量分别为3.75,3,3份时,EPDM硫化胶的定伸应力、拉伸强度和撕裂强度达到最佳值;降低频率、提高应变或温度有利于改善改性炭黑增强EPDM的加工性能。     

PE交联改性在木塑复合材料中的应用

以木粉为填料,废旧 HDPE 为塑料基体,用压制成型法制备了木粉质量含量高达70%的木粉/HDPE复合材料,对比研究PE交联改性技术和MAPE增容技术在木塑复合材料中的应用.结果表明:PE的交联改性可明显提高PE塑料基体的强度,从而可以进一步提高整个复合材料的强度.当MAPE质量含量为l%,DCP质量含量为1.5%时,木塑复合材料的强度可与MAPE质量含量为3%的木塑复合材料相媲美.SEM分析表明:MAPE可以改善木粉与塑料的界面相容性,PE的交联改性对木塑复合材料界面的相容性的改善无贡献.     

封闭型异氰酸酯对碱降解大豆蛋白胶粘剂的交联改性

以Na HSO3(亚硫酸氢钠)封闭的PAPI(多苯基多甲基多异氰酸酯)作为化学交联剂,对DSP[碱降解改性SPI(大豆分离蛋白)]进行交联改性,制得工艺操作性能良好的胶合板用改性SPI胶粘剂。研究结果表明:Na HSO3能封闭PAPI中的活性—NCO基团,从而延长了改性SPI胶粘剂的适用期(为2~5 h);封闭型PAPI能提高改性SPI胶粘剂的耐水性,其湿态胶接强度(0.8~1.0 MPa)满足国家标准中II类胶合板的使用要求;当w(封闭型PAPI)=15%(相对于DSP质量而言)、w(Na HSO3)=0.4%(相对于PAPI质量而言)时,改性SPI胶粘剂具有相对最佳的工艺操作性能和耐水性。     

Mechanical Properties, Biodegradation and Water Vapor Permeability of Blend Films of Soy Protein Isolate and Poly (vinyl alcohol) Compatibilized by Glycerol

Summary Novel blend films of soy protein isolate (SPI) and poly(vinyl alcohol) (PVA) compatibilized by glycerol were fabricated by preparing a solution, and then casting it on a Teflon-coated metal sheet. Mechanical, biodegradation and water vapor permeability of the blend properties were systematically investigated with various methods. SEM analysis results release that the SPI/PVA/glycerol film degrades at a slower rate than pure SPI. The mechanical test showed that the stress at yield point, stress at break point and Young’s modulus were decreased and percentage elongation at yield point and percentage elongation at break point and of SPI/PVA were increased obviously than pure SPI films. The blend plastics were softened and became semi-rigid contributing to the plasticization of glycerol and the crystalline partion of PVA was destroyed by glycerol. Water vapor permeability of SPI/PVA/glycerol showed the minimum at the component of SPI/PVA (100/35) compatibilized by 3.5% of glycerol.     

环氧树脂/纳米纤维素复合材料的制备与性能研究

以木粉为原料制备纳米纤维素（CNF）,经甲基丙烯酸缩水甘油酯（GMA）改性后采用溶液共混法与环氧树脂（EP）复合,制得EP/CNF⁃GMA复合材料;通过对EP/CNF、EP/CNF⁃GMA复合材料力学性能、透光性能、亲水性、热稳定性和微观结构的表征,研究了CNF和GMA含量对复合材料性能的影响及其机理。结果表明,EP/CNF复合材料的拉伸强度、断裂伸长率、透光率随CNF含量的增大呈先增后减的变化趋势,亲水性随CNF含量的增大而增大;CNF含量为0.6 %（质量分数,下同）时,EP/CNF复合材料性能最优,拉伸强度为32.166 MPa,断裂伸长率为20.995 %,600 nm处透光率为79.8 %,接触角为77.34°。经GMA改性后,CNF与EP的相容性得到了改善,提升了EP/CNF复合材料的力学性能和热稳定性;随GMA含量的增加,EP/CNF⁃GMA复合材料的拉伸强度、断裂伸长率、透光率和亲水性均发生变化;GMA含量为4.8 %时EP/CNF⁃GMA复合材料性能最佳,拉伸强度为57.933 MPa,断裂伸长率为18.762 %,600 nm处透光率为86.3 %,接触角为81.42 °。     

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。     

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     

Effects of lignin as a filler on properties of soy protein plastics. I. Lignosulfonate

A series of biodegradable plastics from soy protein isolate (SPI) and lignosulfonate (LS) with a weight ratio of 0:10 to 6:4 were prepared with 40 wt % glycerol as a plasticizer by compression molding. Their 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 tests. The results indicated that the introduction of a moderate LS content from 30 to 40 parts in the blends could simultaneously enhance the tensile strength, elongation, and Young's modulus of soy protein plastics alone. Studies of the water sensitivity of the materials suggested that the strong interaction between LS and SPI could restrict the effect of water on the swelling and the damage of the materials, resulting in lower water absorption. The improvement of the properties was attributed mainly to the existence of the beneficial microphase separation and the formation of crosslinked structures because of the introduction of LS into soy protein plastics. Therefore, a model of a crosslinked network formed from SPI molecules with an LS center was established based on the existence of strong physical interactions between LS and SPI. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3284–3290, 2003     

环氧改性剂对PA6/EVOH共混物性能的影响

介绍了不同环氧改性剂对聚酰胺6（PA6）/乙烯?乙烯醇共聚物（EVOH）共混物的拉伸性能、流变性能、结晶性能的影响,并研究了甲基丙烯酸缩水甘油酯（GMA）与共混物的反应机理。使用转矩测试、红外光谱、氢核磁共振、拉伸测试、旋转流变测试和差示扫描量热法对共混物进行了表征。结果表明,随着改性剂环氧值的增加,共混物的共混转矩、拉伸强度、复数黏度和储能模量均增加,共混物的结晶度和结晶温度降低,断裂伸长率呈先升高后降低的趋势;考虑到加工过程的流动性,GMA改性的共混物性能最佳,拉伸强度提高了8.5 %,断裂伸长率提高了26.6 %;红外光谱和氢核磁共振表明,GMA可以在高温下发生自聚合反应,形成多环氧低聚物,进而与PA6和EVOH反应,提高共混物的性能。     

Reactive blends of gelatinized starch and polycaprolactone‐g‐glycidyl methacrylate

Blends of the modified polycaprolactone (PCL) and the gelatinized starch with glycerin were prepared. The modified PCL, PCL‐g‐glycidyl methacrylate (GPCL), was synthesized by melt reaction of PCL and glycidyl methacrylate (GMA) in the presence of benzoyl peroxide (BPO) in a Brabender mixer. The size of the dispersed starch in the GPCL matrix was found to be smaller than that in the PCL matrix. As the relative content of the GMA groups in the GPCL increases, the elongation at break of the blend showed the highest value at a grafted GMA content of 4.2 wt %. With the increase of the glycerin content in the starch, an abrupt change of the mechanical properties of the blend were observed between 40 and 50 wt % glycerin content based on the starch weight. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1507–1516, 2001     

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.     

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