酚醛树脂/古马隆树脂对再生橡胶性能的影响

研究了204酚醛树脂(204树脂)和古马隆树脂在再生橡胶中的应用。测定了2种树脂对再生橡胶的交联密度、硫化特性、门尼粘度、力学性能、动态力学性能的影响。结果表明,2种树脂均可以有效地降低再生橡胶的门尼粘度;204树脂的固化作用可以提高硫化胶的整体交联密度,有利于再生橡胶力学性能的提高,当其用量为3phr时达到最佳效果;古马隆树脂有利于再生橡胶断裂伸长率的提高,当其用量为4.5phr时达到最佳效果。     

密胺树脂/凤眼蓝纤维复合材料的制备及应用

以凤眼蓝纤维为填充物,通过模压技术制备了密胺树脂/凤眼蓝纤维复合材料。利用力学性能测试仪、粗糙度测试仪以及扫描电镜(SEM)分别表征了密胺树脂/凤眼蓝纤维复合材料的力学性能、凤眼蓝纤维粒子的分散情况以及制品表面光洁度。结果表明,随着凤眼蓝纤维添加量的增加,拉伸强度及弯曲强度呈现出先增大后减小的趋势,其制品表面光泽度呈现出减小的趋势。当凤眼蓝纤维添加量低于40 phr时,密胺树脂与凤眼蓝纤维形成良好的包裹,提高了制品表面的光洁度。密胺树脂/凤眼蓝纤维复合材料的制备不仅降低了餐具的制作成本,更重要的是有效缓解了凤眼蓝泛滥以及白色污染两大环境危机。     

POE/硅橡胶动态硫化共混物的力学性能研究

以聚烯烃弹性体(POE)/有机硅橡胶(质量比50/50)为基体,通过HAKKE密炼机制备了动态硫化热塑性弹性体,考察了硫化剂双-2,5、助交联剂(V4)、增容剂(POE-g-A151)和第三组分用量对弹性体力学性能的影响。结果表明,当硫化剂用量为0.8phr,助交联剂V4用量为0.4phr时,弹性体力学性能显著提高;加入POE-g-A151能起到一定的增容作用。第三组分的加入能有效提高弹性体的力学性能。     

聚酚醚模塑料的研制

以聚酚醚树脂为基体树脂、六次甲基四胺为交联剂,再添加高温黏结剂、石英粉、玻纤等填料,在一定的工艺条件下共混,制得聚酚醚模塑料。研究了不同含量的交联剂、高温黏结剂等成分对聚酚醚模塑料力学性能和耐高温性能的影响。结果表明,六次甲基四胺的用量控制在聚酚醚树脂质量的4%～12%之间,填料的质量分数为60%～75%,其中高温黏结剂的质量分数为15%～20%,所制备的聚酚醚模塑料的各项性能较佳。     

RTM工艺用双酚F型环氧树脂体系研究

本文选用二乙烯三胺和二乙氨基丙胺作固化剂,系统地研究了用于RTM工艺的低粘度双酚F型环氧常温固化体系的工艺特性及力学性能。研究结果表明,用二乙烯三胺固化双酚F型环氧时,其固化物力学性能优异,但适用期较短;用二乙氨基丙胺部分替代二乙烯三胺,得到了适用期为36m in的树脂体系(二乙烯三胺用量2phr、二乙氨基丙胺用量4phr),其树脂固化物拉伸强度为66.8MPa,弯曲强度为102.0MPa。用所确定的树脂体系制得的碳纤维复合材料综合力学性能优良,树脂与碳纤维界面粘结良好,将其应用于RTM成型某型号舱段的制备,制品综合性能优良。     

丁苯膨胀橡胶的制备与性能研究

以自制高吸油树脂、石油树脂以及其他橡胶助剂与丁苯橡胶(SBR)物理共混制备遇油膨胀橡胶(OSR),研究了吸油树脂用量、石油树脂用量对OSR力学性能和吸油膨胀倍率的影响。结果表明:随着吸油树脂用量的增加,OSR的吸油膨胀倍率显著增加,但力学性能明显降低;石油树脂有助于改善OSR的相容性,提高OSR的力学性能和吸油膨胀倍率;吸油树脂和石油树脂适宜用量分别为30phr和10phr。     

PP/POE-g-MAH/MF微孔发泡复合材料的制备及性能研究

采用POE-g-MAH作为聚丙烯和密胺树脂的增容剂,用化学发泡法制备了PP/POE-g-MAH/MF微孔复合材料,并探讨密胺树脂含量对微孔聚丙烯复合材料综合性能的影响。研究结果表明,密胺树脂粉末使复合材料结晶提前,对聚丙烯发泡过程起异相成核作用,导致微孔孔径变小并致密。随着密胺树脂含量的增加,微孔复合材料的拉伸强度、断裂伸长率和冲击强度先增大后减小。当密胺树脂的含量为2%时,微孔复合材料的强度和冲击韧性最佳。     

PEK-C增韧环氧树脂的研究Ⅰ

采用酚酞基聚芳醚酮为增韧剂,以芳香胺为固化剂,制备出一种改性环氧树脂。实验结果表明:当酚酞基聚芳醚酮用量为45phr时,改性环氧树脂综合性能最好。改性树脂的断裂韧性KIC最高,达到2.94MPa·m1/2,冲击强度达到了31.83k J/m2,均比增韧前提高了180%;拉伸强度达到了80.67MPa。同时,改性树脂的粘接力学性能得到较大提高,常温剪切强度和200℃剪切强度分别为31.27MPa和20.48MPa。     

PLA/改性MMT复合材料的性能

以十六烷基三甲基溴化铵(CTAB)为改性剂对蒙脱土(MMT)进行改性,将其填充到聚乳酸(PLA)中,采用熔融插层法制备了PLA/改性MMT复合材料,并研究了复合材料的性能。结果表明:添加MMT可提高复合材料的阻燃性能和耐热性能;添加未改性MMT降低了复合材料的力学性能,当其用量为9 phr时,复合材料的拉伸强度从42.1 MPa降至38.6 MPa,断裂拉伸应变从4.5%降至2.2%,冲击强度从15.2 kJ/m~2降至8.6 kJ/m~2;添加适量(3~5 phr)改性MMT可提高复合材料的力学性能,当其用量为5 phr时,复合材料的拉伸强度和断裂拉伸应变均达最大值,分别为47.2 MPa和10.6%,当其用量为3 phr时,复合材料的冲击强度达最大值,为25.2 kJ/m~2。     

挤出过程中交联聚氯乙烯的研究

应用过氧化二异丙苯 /苯乙烯 /三乙醇胺体系在挤出过程中实现了聚氯乙烯的一步交联 ,研究了三乙醇胺和过氧化二异丙苯用量对交联产物力学性能及交联凝胶率的影响。研究发现 ,三乙醇胺对PVC交联结构的形成具有明显的促进作用。在苯乙烯用量 5 phr,三乙醇胺用量为 0 33phr时 ,过氧化二异丙苯在 0 15phr取得最佳值 ;当苯乙烯用量 5 phr,过氧化二异丙苯用量 0 15 phr时 ,三乙醇胺用量在 0 4hpr取得最佳值。交联可以使聚合物材料的力学强度得到提高     

TAS-2A分散剂在塑料加工中的应用

将新型塑料加工助剂TSA-2A分散剂用于功能母粒、无机高填充改性塑料的生产。研究结果表明:TSA-2A分散剂能改善塑料色母粒的成型加工性和色母粒的分散性,提高高填充改性塑料的成型加工性和力学性能。     

增塑剂对脲醛树脂模塑料性能的影响

以尿素、甲醛及木质纤维素等为原料,通过添加聚乙二醇6000、聚乙烯蜡、磷酸三苯酯和对甲苯磺酰胺4种增塑剂,研究其对脲醛树脂模塑料(UF)流动性能、力学性能的影响,并采用动态热机械分析仪(DMA)分析了脲醛树脂模塑料的动态力学性能。研究表明,4种增塑剂均能明显提高脲醛树脂模塑料的流动性能;聚乙二醇6000对脲醛树脂模塑料的流动性能和力学性能增强最为明显,并增强了脲醛树脂模塑料的耐热性能,添加的质量分数为1.0%~3.0%时脲醛树脂模塑料的综合性能最优,弯曲强度为80~86 MPa,冲击强度为1.63~1.75 kJ/m2,流动性能为76~83 mm。     

Process optimization of sweet potato pulp‐based biodegradable plastics using response surface methodology

Biodegradable plastics were produced from sweet potato pulp (SPP) and cationic starch (CS) or chitosan composite (CC) by compression molding and their mechanical properties were tested. A universal testing machine, Rockwell hardness tester, and Izod impact tester were used for testing the mechanical properties (flexural strength, Rockwell hardness, and Izod strength) of the plastics. A central composite second‐order design was used to study the effects of temperature, time, and moisture content on the flexural strength, Rockwell hardness, and Izod strength of SPP/CS and SPP/CC blended plastics. The flexural strength, Rockwell hardness, and Izod strength of SPP‐based plastics was 101.1–305.9 kg/cm², R29.0–R96.7, and 0.6–3.0 kg cm cm^?2, respectively. Regression analysis predicted the optimal mechanical properties (flexural strength, Rockwell hardness, and Izod strength) to be attained with a 150–160°C temperature, 15–20‐min reaction time, and 20–23% moisture content. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 423–434, 2002     

聚乳酸纤维/聚乙烯醇纤维协同增强热塑性淀粉复合材料

为提高热塑性淀粉（TPS）塑料的力学和耐水性能,通过挤出工艺制备了含量为1 %（质量分数,下同）的聚乳酸纤维（PLAF）及不同含量的聚乙烯醇纤维（PVAF）共同增强的热塑性淀粉复合材料。研究了含量为0.2 %~1.4 %的PVAF对TPS/PLAF/PVAF复合材料力学性能、断面形貌、耐水性能及转矩流变性能的影响。结果表明,同时加入PLAF和PVAF能有效提高复合材料的力学性能及表面耐水性能;当PLAF和PVAF含量为1 %时,复合材料的拉伸强度从纯TPS的1.98 MPa提高到10.53 MPa,冲击强度由纯TPS的33.4 kJ/m²提高到62.23 kJ/m²,水接触角由纯TPS的46.34°提高到65.02°,TPS/PLAF/PVAF复合材料的平衡扭达到最大值15.75 N·m。     

Plastic performance of soybean protein components

Soybean proteins recently have been considered as petroleum polymer alternatives in the manufacture of adhesives, plastics, and various binders. The objective of this work was to characterize the plastic performance of soybean protein components during molding processes. Two major soybean protein fractions, 7S-rich globulin (7S-RG) and 11S-rich globulin (11S-RG) were separated from defatted soybean flour, and their purity was examined by sodium dodecyl sulfate-polyacrylamide gel eletrophoresis and high-performance liquid chromatography. The thermal transition properties of the two fractions at 10% moisture content were 137.6°C for 7S and 163°C for 11S, as analyzed using differential scanning calorimetry (DSC). Plastics were prepared using a hot press at various molding temperatures that were selected based on the proteins’ thermal transition temperatures obtained by DSC. The plastics were evaluated for mechanical properties, water absorption, and microstructure. The plastics prepared with temperatures at or close to the thermal transition temperature showed a smooth, uniform, and complex structure. Results showed that the plastics made from 11S-RG at its thermal transition temperature were stronger (35 MPa) and had lower water absorption than those made from 7S-RG at 145°C (26 MPa). The plastics made from the 7S- and 11S-RG mixture had the highest tensile strength (39 MPa) and medium water absorption compared to those made from 7S- and 11S-RG alone. These mechanical properties and water absorption behaviors were significantly affected by molding temperatures. The results obtained from this research indicated that interaction between 7S- and 11S-RG could occur during molding and that thermal transition temperature played an important role in thermal processing of soybean proteins.     

Soy protein–lignosulphonate plastics strengthened with cellulose

A series of biodegradable plastics from soy protein and lignosulphonate (SL) were strengthened with cellulose powder (CP) by melt blending and compression molding. The effects on the morphology and properties of the blends of introducing CP were investigated by wide‐angle X‐ray diffraction, differential scanning calorimetry, dynamic mechanical thermal analysis, scanning electron microscopy, and tests of tensile and water absorption. It is worth noting that introducing CP obviously improved the mechanical properties and water resistivity of composite plastics. With an increase in CP content, the tensile strength and Young's modulus of the blend materials increased. The experimental results indicate that a certain degree of miscibility between SL and CP and a strong interaction among various molecules of the components, resulting in strengthened materials. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1685–1689, 2003     

GF及偶联剂改性PVC/稻壳木塑复合材料

采用模压成型的方式、通过实验探索玻璃纤维(GF)含量及偶联剂处理对聚氯乙烯(PVC)/稻壳木塑复合材料的力学特性和耐磨性的影响。实验结果表明:PVC/稻壳木塑复合材料的硬度随GF含量增加呈现先减小后增大的趋势。GF含量在15%以下时,随着GF用量的增大,木塑复合材料的拉伸强度与冲击强度总体上随之变大,超过15%则随GF含量增大而减小。而弯曲强度出现先减后增的趋势,弯曲弹性模量则与之相反。木塑复合材料的耐磨损性在GF含量为15%时最佳,摩擦系数在10%时最大。合适的偶联剂处理能增强木塑复合材料的力学性能和耐磨性。其中γ–氨丙基三乙氧基硅烷(KH550)的增强效果比较好,钛酸酯不能提高PVC/稻壳木塑材料的力学性能和耐磨性。     

阻燃增强PET工程塑料的研制

通过熔融共混工艺,利用双螺杆挤出机制备了聚对苯二甲酸乙二酯(PET)/玻璃纤维(GF)/溴化环氧树脂共混体系,研究了各组分对共混体系力学性能和阻燃性能的影响。结果表明,GF含量的增加不仅可以全面提高共混体系的力学性能,而且可以提高共混体系的阻燃性能;随着阻燃剂溴化环氧树脂含量的增加,共混体系的阻燃性能显著改善,但力学性能稍有下降。     

Effect of coal filler on the properties of soy protein plastics

The influence of ultrafine coal filler (UFC) content on tensile properties, water absorption, and biodegradability of soy protein plastics were investigated. The addition of UFC in the soy protein plastics, with different content of glycerol as a plasticizer, was at different ratio varying from 10:0 to 6:4. Blend sheets of the soy protein composites were prepared by the compression molding processing. The results show that, with 23.08 wt % glycerol, the tensile strength and elongation at break for the soy protein sheet with coal filler (range from 5 to 30 parts) can be enhanced as compared with nonfilled soy protein plastics. Water resistance of the soy protein plastics improves with the increase in UFC content. The derivative thermogravimetry (DTG) curves indicate a double‐stage degradation process for defatted soy flour (SPF), while three‐stage degradation process for soy plastics and the soy protein composites. FT‐IR, XPS, and SEM were applied to study the interfacial interaction between coal macromolecules and soy protein molecules in UFC filled soy protein plastics. The results demonstrated that there is strong interfacial interaction in the soy protein plastics caused by the compression molding processing. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3134–3143, 2006     

Optimal compositions of molded phenolic resins and its properties

Phenolic resins [commercial (CP), pure (PP), and woodflour-filled (WP)] containing different levels of hexamine, were evaluated in terms of curing behavior as well as thermal, electrical, and mechanical properties. The degree and rate of curing increase markedly with the rise of the hexamine content; however, the dielectric constant, dielectric loss, and dissipation factor decrease gradually. Dielectrical values decrease with the increase of the applied frequency. When the ratios of hexamine to phenolics are increased, samples become harder and experience increased molding shrinkage. With the increase of molding time or temperature, the surface hardness and molding shrinkage improve. The optimal hexamine contents of WP and PP are determined with respect to the above properties.