FPE,CaCO3非弹性体增韧PVC／CPE体系的研究

介绍以ＰＥ固相接枝马来酸二丁酯（简称ＦＰＥ）非弹性体增韧ＰＶＣ／ＣＰＥ体系。在ＰＶＣ／ＣＰＥ＝１００／５．５及１００／１０（质量比）体系中,加入５．５质量份ＦＰＥ后,其缺口冲击强度由１３．５ｋＪ／ｍ２、３１．５ｋＪ／ｍ２提高到１８．１ｋＪ／ｍ２、４０．８ｋＪ／ｍ２;拉伸强度由４９．４ＭＰａ、４１．７ＭＰａ提高到５２．９ＭＰａ、４２．７ＭＰａ,表明ＦＰＥ对ＰＶＣ／ＣＰＥ体系具有增韧增强双重作用。在ＰＶＣ／ＣＰＥ／ＦＰＥ三元体系中,加入适量的ＣａＣＯ３＊也有增韧作用,添加５质量份时,体系的缺口冲击强度由１８．１ｋＪ／ｍ２提高到２４．１ｋＪ／ｍ２。通过流变性能的测试表明,ＦＰＥ的加入能改善体系的流动性能。此外,还用ＳＥＭ研究了体系的增韧机理,认为在ＰＶＣ／ＣＰＥ／ＦＰＥ体系中,ＣＰＥ属弹性体增韧类型,ＦＰＥ属非弹性体增韧类型,两种机理同时存在。     

MAH教枝LDPE对PET／LDPE共混物增容作用的研究

本文研究了马来酸酐在引发剂过氧化二异丙苯存在下，与ＬＤＰＥ在挤出机中进行熔融接枝反应，所得接枝物ＧＰＥ对ＰＥＴ／ＬＤＰＥ共混体系的增容作用。共混物的冲击强度及应力应变曲线结果表明，ＧＰＥ能明显改善共混体系的相容性，提高共混体系的冲击强度，仅用２０％的ＧＰＥ就能使共混物由脆性断裂变为韧性断裂。利用ＳＥＭ观察共混物的冲击断面形貌，结果表明，ＰＥＴ与ＬＤＰＥ完全不相容，ＧＰＥ能明显改善ＰＥＴ与ＬＤＰＥ共     

聚醚砜／碳纤维复合材料的断裂行为研究

本文用湿法制造无纬预浸布，用模压法成型两种不同基体村质的聚醚砜／碳纤维复合材料层压板。分别用ＥＮＦ试样和三点弯曲试样（裂纹方向和纤维方向一致）研究了ＰＥＳ／ＣＦ复合材料的Ⅱ型层间断裂行为及Ⅰ型纤维层间断裂行为，用仪器化Ｃｈａｒｐｙ冲击试验方法研究了ＰＥＳ／ＣＦ复合材料的冲击性能。断口形貌的电镜分析表明，ＰＥＳ／ＣＦ复合材料的界面粘接情况良好。     

改性聚氯乙烯体系的脆／韧转变研究

用缺口冲击实验研究了ＣＰＥ、ＮＢＲ、ＤＯＰ、ＰＭＭＡ、ＰＳ等改性对ＰＶＣ脆／韧转变变温度的影响。实验表明，ＰＭＭＡ、ＰＳ等脆性塑料对ＰＶＣ具有不同于ＣＰＥ、ＮＢＲ等弹性体的改性机理，两者均可使ＰＶＣ体系的脆／韧转变温度发生变化。随改性剂含量的增加，用传统改性剂（ＣＰＥ、ＤＯＦＦ等）改性的ＰＶＣ体系的脆／韧转变变温度呈下降趋势，而脆性塑料则使体系的转变温度具有一低温度。     

碳纤维／PE—Ⅱ尼龙复合材料的力学性能

本文探讨了碳纤维表面处理的方法，ＣＦ含量对ＣＦ／ＰＥ－Ⅱ复合材料拉伸强度，冲击强度的影响，并研究了复合材料的摩擦磨损性能及尺寸稳定性。结果表明，ＣＦ／ＰＥ－２尼龙复合材料具有较高的强度和极优良的耐磨性及尺寸稳定性，是一种新型的高性能复合材料。     

PVC/PVDF/CPE共混体系研究

以ＣＰＥ作为ＰＶＣ／ＰＶＤＦ的增容剂,研究了ＰＶＣ／ＰＶＤＦ／ＣＰＥ三元共混新体系。对不同组成的共混物的物理机械性能进行测试,分析了讨论了ＰＶＤＦ／ＣＰＥ的增韧效果和机理。结果表明：ＣＰＥ对ＰＶＣ／ＰＶＤＦ共混体系有明显的增容作用,ＰＶＤＦ／ＣＰＥ并用对增韧ＰＶＣ有显著的协同效应。     

PP/HDPE/EPDM共混物的研究

研究了聚丙烯（ＰＰ）、高密度聚乙烯（ＨＤＰＥ）和ＥＰＤＭ共混制备非交联型ＰＰ／ＨＤＰＥ／ＥＰＤＭ三元共混物。结果表明，当共混比ＰＰ／ＨＤＰＥ／ＥＰＤＭ＝６５／２０／１５，活性碳酸钙为３０份，ＨＤＰＥ品种为ＧＦ７７５０，采用先把ＨＤＰＥ和ＥＰＤＭ预制成混料再与ＰＰ共混的方法，可得到性能良好的ＰＰ／ＨＤＰＥ／ＥＰＤＭ共混物。     

LARGE SCALE PURIFICATION OF PHOSPHOGLYCERATE KINASE（PGK） AND GLYCERALDEHYDE 3－PHOSPHATE DEHYDROGENASE（GAPDH） FROMYELLOW PEAS BY PEG／REPPAL PES AQUEOUS TWO PHASE SYSTEM AND ION EXCHANGE CHROMATOGRAPHY

ＬＡＲＧＥＳＣＡＬＥＰＵＲＩＦＩＣＡＴＩＯＮＯＦＰＨＯＳＰＨＯＧＬＹＣＥＲＡＴＥＫＩＮＡＳＥ（ＰＧＫ）ＡＮＤＧＬＹＣＥＲＡＬＤＥＨＹＤＥ３－ＰＨＯＳＰＨＡＴＥＤＥＨＹＤＲＯＧＥＮＡＳＥ（ＧＡＰＤＨ）ＦＲＯＭＹＥＬＬＯＷＰＥＡＳＢＹＰＥＧ／ＲＥＰＰＡＬ...     

PET—PEG嵌段共聚物纤维和PET／PET—PEG共混纤维的吸混性和抗静电性能 …

本文对ＰＥＴ－ＰＥＧ嵌段共聚物的可纺性,ＰＥＴ－ＰＥＧ纤维和ＰＥＴ／ＰＥＴ－ＰＥＧ共混纤维的吸湿性的抗静电性能进行了研究,探讨了共混纤维的抗静电机理。     

环氧玻璃钢层合板Ⅰ型和Ⅱ型层间断裂与断口分析

本文利用扫描电子显微镜ＳＥＭ－５０５观察了Ｓ－ＧＦ／ＥＰ６４８复合材料层合板Ⅰ型和Ⅱ型层间断裂的断口形貌，发现不同铺层角，冲击损伤以及湿热效应等因素对该复合材料层合板断裂特性及其断口形貌皆有明显的影响。     

无卤阻燃PF/EP/GF布复合材料的固化性能和阻燃性能

采用环氧树脂(EP)作固化剂,2,4,6-三(二甲胺基甲基)-苯酚(DMP30)作固化促进剂改善酚醛树脂(PF)的固化性能,以氢氧化铝和有机磷阻燃剂协同改性其阻燃性能,将其涂覆于玻璃纤维(GF)布上,压制成无卤阻燃PF/EP/GF布复合材料.用傅立叶变换红外光谱(FTIR)仪和差示扫描量热(DSC)仪对无卤阻燃PF/EP/GF布复合材料的固化反应机理、固化反应动力学进行了分析研究,并测试了该复合材料的阻燃性能.结果表明,无卤阻燃PF/EP/GF布复合材料的固化反应表观活化能Ea=75.7 kJ/mol、反应级数n=0.91,起始固化温度、固化峰顶温度、固化终止温度分别为108.6、133.2、152.9℃;当氢氧化铝质量分数为14%、DMP30质量分数为1%、有机磷阻燃剂质量分数为4.8%时,无卤阻燃PF/EP/GF布复合材料的固化性能、阻燃性能均达到较佳状态.     

光固化ES/CEP共混物及其复合材料力学性能研究

设计了不同质量比的有机硅环氧树脂/脂环族环氧树脂(ES/CEP)共混物,采用光固化技术,分别制备了ES/CEP共混物试样(EP)、玻璃纤维增强复合材料(GF/ES-CEP)以及GF/ES-CEP复合材料为补片的粘接修理铝合金试样,重点研究了有机硅环氧树脂(ES)的质量分数对试样拉伸力学性能的影响。结果表明:CEP添加ES、EP的抗拉强度有逐渐降低的趋势,延伸率则先增加后下降,EP的力学性能在加入15%的ES时达到最佳;GF/ES-CEP复合材料抗拉强度和延伸率则随ES比例的增加先上升后下降。以GF/ES-CEP复合材料为补片的复合材料粘接修理铝合金试样主要发生胶层与损伤结构界面的剥离破坏,表明复合材料力学性能优于界面力学性能。水浴处理后,GF/ES-CEP复合材料修理铝合金试样的力学性能有明显下降,加入适量有机硅树脂可以提高修复试样的耐湿热性能。     

Friction and Wear of MoO3/Graphene Oxide Modified Glass Fiber Reinforced Epoxy Nanocomposites

In order to further improve the tribological performance of glass fiber reinforced epoxy (GF/EP) composites, highly flexible, binder‐free, molybdenum trioxide MoO₃ nanobelt/graphene oxide (GO) film (f‐MoO₃‐GO) is prepared by a hydrothermal method. Herein, f‐MoO₃‐GO is adopted to modify GF/EP composites prepared through the vacuum‐assisted resin transfer molding method. The neat GF/EP and MoO₃‐GO modified GF/EP composites are also fabricated for comparison. The tribological performance is performed using a ball‐on‐disc (“steel‐on‐polymer”) configuration under a dry sliding condition. The coefficient of friction is reduced from 0.61 for neat GF/EP composites down to 0.23 for f‐MoO₃‐GO modified GF/EP (f‐MoO₃‐GO/GF/EP) composites and the anti‐wear performance is improved by more than four times. The worn surface morphological observation for the composite samples is used to explain the possible wear micro‐mechanisms. The wear reducing effect of the f‐MoO₃‐GO/GF/EP composites can be assigned to the increased self‐lubricating effect of f‐MoO₃‐GO. With the combined advantageous properties of the used individual components, these unique composites can be used for many other applications.     

SF/PF复合材料冲击性能的研究

研究了剑麻纤维(SF)的表面处理方式、纤维的含量、纤维的长度及与玻璃纤维混杂增强对SF／酚醛树脂(PF)复合材料冲击强度的影响，借助SEM观察复合材料的冲击断面，进行了微观结构分析。结果表明，SF经过碱处理后复合体系的冲击强度提高了34％，当SF的质量分数为40％、长度为6ram时，SF／PF复合材料冲击强度达到最大值，当SF与玻纤质量比为1：1时，复合材料冲击强度出现了混杂效应。     

PEEK层间增韧碳纤维环氧树脂基复合材料的性能研究

为了改善碳纤维/环氧树脂(CF/EP)层合板层间断裂韧性较差的问题,采用预浸料层间涂层和模压工艺制备聚醚醚酮(PEEK)层间增韧CF/EP层合板。探究PEEK含量对CF/EP层合板Ⅱ型层间断裂韧性和冲击强度的影响。结果表明:PEEK的加入有效提高CF/EP层合板的Ⅱ型层间断裂韧性和冲击强度。当PEEK含量为2%,层合板的断裂韧性和冲击强度分别达到1 253 J/m²和259 kJ/m²,与纯层合板相比分别提高61.5%和32.8%。实验分析PEEK增韧机理,为研究高附加值复合材料产品提供参考。     

RTM制备玻璃纤维增强环氧树脂复合材料的力学性能分析

以环氧树脂为基体,短切玻璃纤维和玻璃纤维布为增强材料,通过RTM工艺制备了玻璃纤维增强环氧树脂(GF/EP)复合材料,并研究了RTM工艺制备玻璃纤维布增强环氧树脂(L-GF/EP)和短切玻璃纤维增强环氧树脂(S-GF/EP)复合材料的拉伸和弯曲性能,分析了开孔对两种复合材料拉伸性能的影响。结果表明:在拉伸过程中,开孔试样因孔边产生的应力集中,导致其拉伸强度与无孔试样相比下降了30%左右;玻纤铺层类型的不同对复合材料的力学性能具有显著影响;L-GF/EP复合材料内部结构完整,在载荷作用下,复合材料的弯曲断裂呈现一定的假塑性断裂模式,达到弯曲极限挠度值后,出现一定程度的回弹现象,其力学性能优于S-GF/EP复合材料。     

Sand erosion and crack propagation mechanism of Cr/CrN/Cr/CrAlN multilayer coating

Herein, we have deposited Cr/CrN/Cr/CrAlN multilayer coatings with various modulation ratios on TC11 alloy substrate using cathodic arc system. The influence of various modulation ratios on microstructure and Al₂O₃ sand erosion behavior of coatings is systematically studied. Results reveal that the coatings are about 200 nm per cycle and total thickness is 8 μm. Five groups of coatings exhibit high hardness (>3000 HV_0.025). The coating with modulation ratio of 12 adhesion can reaches 55 N. The residual stress increases with the decrease of the modulation ratio, but the increase is generally low (less than ?2 GPa). In addition, according to sand erosion test, it is found that sand erosion resistance of multilayer coating is significantly around 5 times higher than TC11 alloy matrix. The erosion morphology shows that a large number of irregular cracks and layered spalling appear on the surface of the coating, indicating that the cracks are constantly initiated under the continuous impact of the sand and gravel，and finally gather together and then spalling. Moreover, dynamic response and stress field of the coating under the impact of single sand (Al₂O₃) are studied by numerical simulations. It is determined that coating cracking is caused by high tensile stress under CrAlN layer. In addition, according to crack propagation morphology and influence of different interfaces between multilayered structures on crack tips, propagation/termination mechanism of cracks is analyzed in detail. Cracks are easy to initiate in hard CrAlN layer and consume a lot of energy after propagating into soft Cr layer, thereby ending at next soft and hard interfaces. These results provide experimental and theoretical support for the study of high tenacity and anti-erosion coating.     

Influence of epoxy resin on the microstructure and cavitation erosion of as-sprayed 8YSZ coating

The microstructures of materials are sensitive to shock waves and microjets induced by bubble collapse. The microstructure of coatings is thus closely related to their cavitation performance. Coating defects always act as the preferential sites for the bubble growth; thus, the materials around pores have been spalled preferentially under strong impact. In this study, epoxy resin (ER) was introduced into as-sprayed 8?wt% yttria-stabilized zirconia (8YSZ) coating by vacuum impregnation to prepare 8YSZ-ER coating. Results showed that the hardness, toughness, cohesive strength, and density of 8YSZ-ER coating are greatly improved. Cavitation performance is also improved; 8YSZ coating exhibited only a deceleration period whereas 8YSZ-ER coating showed a long steady-state period. This finding was mainly attributed to the enhanced compactness and cohesive strength of 8YSZ-ER coating, which caused the impact force to be evenly distributed on the specimen surface without accumulating in the pores. Cracks were also deflected, turned and terminated due to the presence of ER. Moreover, the relationship between ER aging and the damage mechanism of 8YSZ-ER coating under cavitation erosion was also examined.     

Impact resistance of fibrous glass reinforced plastics using polycarbonate‐polydimethylsiloxane block copolymer

By using reactive polydimethylsiloxanes that have phenolic hydroxyl groups at the ends of the chain, a polycarbonate‐polydimethylsiloxane (PC‐PDMS) block copolymer was prepared, and the properties of fibrous glass reinforced plastics (GF‐PC) using this copolymer were examined. The Izod impact value of the PC‐PDMS/GF composite increases with an increase in the degree of polymerization of reactive PDMS (n) between 40 and 160. When n is 40, the Izod impact value of the PC‐PDMS/GF composite is equal to that of the PC/GF composite. The Izod impact value is independent of the PDMS content of the copolymer when it is between 2 and 4 wt %. The PC‐PDMS/GF composite is superior, in the balance between fluidity and impact resistance, to the PC/GF composite. From the results of SEM, adhesion between the polymer and GF of the PC‐PDMS/GF composite is superior to that of the PC/GF composite. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1123–1127, 2002     

Kinetics of wear of epoxide coating modified with glass microspheres and exposed to the impact of alundum particles

The influence of epoxide coating modification with glass microspheres on the erosive wear of the coating is discussed in this paper. Increase in the resistance to erosive wear of a three-layer epoxide coating including the interlayer modified with glass microspheres of a diameter <30 μm and a mass fraction of 10% was obtained. It can be accounted for by the damping of energy which is released during the collision between the impact particle and the organic surface and then dumped by the glass microspheres.