聚丙烯／绢英粉复合材料的抗紫外线性能研究

制备了聚丙烯／绢英粉复合材料，并对其抗紫外线性进行了研究，结果表明，绢英粉是一种很有发展前景的聚丙烯光照稳定剂，该复合材料具有很好的抗紫外光老化性能。     

绢英粉对填充EPDM物理性能的影响

对绢英粉用量、细度及其改性对填充ＥＰＤＭ物理性能的影响进行了研究,并与多种矿质填料进行了等量对比试验。试验结果表明,３２５目的绢英粉即可满足填充ＥＰＤＭ的各项物理性能要求,且撕裂强度比１５００目的好,用量以１２０～１６０份为宜。绢英粉对ＥＰＤＭ的补强效果仅处于矿质填料的中间水平;硅烷类偶联剂可改善绢英粉与ＥＰＤＭ大分子的物理或化学结合,提高３００％定伸应力和撕裂强度。     

纳米TiO2填充聚丙烯的研究

将表面处理的纳米TiO2填充到PP中制备纳米复合材料，研究了纳米级二氧化钛对聚丙烯力学性能及其耐老化性能的影响，研究结果表明，添加纳米级二氧化钛可以使聚丙烯的冲击强度以及耐紫外老化性能提高。     

木粉高填充改性聚丙烯再生料的研究

探讨了木粉填充改性、不同的木粉含量、种类以及木粉的预自理处理对聚丙烯再生料的力学发性能及挤出成型的影响。     

聚丙烯填充改性研究进展

介绍了聚丙烯填充材料的种类特点．综述聚丙烯的填充改性的研究．指出了聚丙烯填充改性的发展趋势。     

石墨填充聚丙烯的研究

着重对石墨填充聚丙烯的某些性能作了初步探讨了，除了提高该材料的力学性能外，其热传导性有了较大改善，从而扩大了其应用范围，可用于耐腐蚀设备、换热设备、贮存设备等领域，很有推广价值。     

改性滑石粉填充聚丙烯的研究

主要介绍了采用滑石粉填充聚丙烯的方法来提高其力学性能。利用改性好的滑石粉填充到聚丙烯中,研究了未改性滑石粉和不同偶联剂改性滑石粉,以及不同粒径滑石粉以不同比例同填充到聚丙烯中,对聚丙烯力学性能的影响。     

蛋壳粉填充改性聚丙烯基木塑复合材料性能研究

采用双螺杆挤出机制备了不同配方的聚丙烯(PP)/木粉/蛋壳粉复合材料(WPC),研究了蛋壳粉用量对WPC的拉伸强度、冲击强度、断裂伸长率、硬度、维卡软化温度、熔体流动速率(MFR)的影响.结果表明,随着蛋壳粉用量的增加,拉伸强度先增加后降低,冲击强度逐渐减小,硬度逐渐增加,断裂伸长率在蛋壳粉用量不大于15份时基本不变,...     

云母对PP抗紫外光老化性能的影响

将云母填充聚丙烯(PP)进行光老化前后的力学性能比较,并采用紫外-可见光分光光度计、扫描电子显微镜等对云母及复合材料进行研究.实验表明:具有高径厚比的云母容易在塑料流体流动过程中沿着流动方向并行取向,取向后的云母不仅有利于提高PP材料的力学性能,而且云母对紫外光具有层间反射、干涉和遮蔽等效应,同时降低云母粒径,提高径厚比可有效提高改性PP的力学性能和抗紫外光老化性能.     

丙纶纤维自增强聚丙烯树脂的研究

以丙纶纤维为增强体,聚丙烯树脂为基体,采用热压成型的方法制备丙纶纤维/PP复合材料板材.研究了不同热压温度、不同纤度的丙纶纤维用量对复合材料力学性能的影响.结果表明:本实验最佳热压温度为195℃,在此温度下,随着纤维用量的增加,复合材料的拉伸强度呈先升后降的趋势,在用量为15%时达到最高点,纤度为240D的丙纶纤维/P...     

Mechanical properties of flame retardant filled polypropylene composites

The flammability performance and mechanical behaviors for halogen‐based and non‐halogen‐based flame retardant (FR) filled polypropylene (PP) composites were investigated in this study. The halogen‐based FR system consisted of a mixture of brominated phosphate ester and antimony trioxide (BR), and the halogen‐free FR was a magnesium hydroxide (MH). It was found from limiting oxygen index measurements that 60 wt % of MH was needed in order to achieve the same degree of flammability as the composite containing only 30 wt % of BR. Scanning electron microscopy examinations of the fractured specimens indicated that the interfacial bond strength between PP and MH was stronger than that for PP and BR. The notched Charpy impact strength and the impact fracture toughness were measured and compared. The discrepancies between the two impact test results could be correlated after kinetic energy correction was applied to the Charpy impact strengths. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2718–2728, 2001     

PP及PP/EPDM共混物室内外老化行为的研究

通过中国西部3个地区（新疆尉犁、西藏拉萨和四川成都）室外自然老化和室内加速老化（热氧、紫外老化）的对比,研究了聚丙烯及聚丙烯/三元乙丙橡胶（PP/EPDM）共混物室内外老化前后力学性能的变化和表面微观形态的变化,以及其室内外老化的对应关系。结果表明,室外老化初期PP的拉伸强度提高,老化中后期随着降解程度加剧拉伸强度下降;EPDM的加入提高了PP的耐老化性能,其中成都地区老化试样最为明显,24个月后拉伸强度保持率高达115 %;PP和PP/EPDM共混物室内热氧老化后拉伸强度变化不大,紫外老化后拉伸强度则呈现下降趋势;综合考虑热氧和紫外老化,通过时间等效关系可以更好地联系室内外老化,为预测材料在自然状态下的服役寿命奠定了基础。     

Low percolation threshold and high conductivity in carbon black filled polyethylene and polypropylene composites

High electrically conductive composites have been manufactured using twin and single screw extruders from carbon black with polyolefin. High density, low density polyethylene, polypropylene, polyethylene/polypropylene copolymer, and maleic anhydrite grafted polypropylene have been compounded with three carbon blacks (CBs), i.e., Black Pearl, Printex, and Ketjen, respectively. The lowest percolation threshold (0.8 vol %) for conductive composite was obtained using Ketjen CB blended with high density polyethylene (HD3690, MFI = 36 g/10 min). Polypropylene composites also achieved low percolation thresholds of 1.5 vol % when compounded with Printex or Ketjen CB. Decreasing melt viscosity of polymer matrix resulted in decreasing resistivity of composites. Ketjen CB showed the best conductive behavior for both polyethylene and polypropylene composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Damping behavior of wood filled polypropylene composites

The damping coefficient (tanδ) of wood flour filled polypropylene composites, having varying filler concentrations were measured using the free vibration decay of disk‐shaped specimen, vibrating in flexural vibration mode. The damping coefficients decreased with the increase of filler load in composites. There was no significant difference in damping behavior of composites with and without compatiblizer at low filler level (upto 30%). At higher filler loading (>30%), composites with compatiblizer had lower damping coefficient suggesting improved interfacial adhesion between wood and polypropylene. The damping in composite is attributed to the damping because of the composite constituents and damping at the interface. The damping because of interface was estimated using a model and was found to increase with the increase in filler loading. At higher filler content, damping due to interface in composites with compatiblizer was significantly lower than in composites without compatiblizer suggesting a better interfacial adhesion between the wood filler and polypropylene matrix with compatiblizer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Hygrothermal aging and tensile behavior of injection‐molded rice husk‐filled polypropylene composites

The effect of the filler volume fraction on the tensile behavior of injection‐molded rice husk‐filled polypropylene (RH–PP) composites was studied. Hygrothermal aging behavior was also investigated by immersing the specimens in distilled water at 30 and 90°C. The kinetics of moisture absorption was studied from the amount of water uptake by specimens at regular interval times. It was found that the diffusion coefficient and the maximum moisture content are dependent on the filler volume fraction and the immersion temperatures. Incorporation of RH into the PP matrix has led to a significant improvement in the tensile modulus and a moderate improvement in the tensile strength. Elongation at break and energy at break, on the other hand, decreased drastically with the incorporation of the RH filler. The extent of deterioration incurred by hygrothermal aging was dependent on the immersion temperature. Both the tensile strength and tensile modulus deteriorated as a result of the combined effect of thermal aging and moisture attack. Furthermore, the tensile properties were not recovered upon redrying of the specimens. Scanning electron microscopy was used to investigate the mode of failure of the RH–PP composites. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 742–753, 2001     

Crystallization behavior of starch‐filled polypropylene

Starches of different granule sizes, including corn, rice, and amaranth starches, were used to prepare starch‐filled polypropylene (PP) and the effect of starch granule size on crystallization behavior PP was investigated. Differential scanning calorimetry and scanning electron microscopy were used to monitor the energy changes of the crystallization of the melt and to characterize the morphology of PP/starch composites, respectively. Little interaction was observed between starch and PP despite the difference in starch granule size. The crystallization temperature of PP decreased with the addition of starch and this decrease became more apparent with increasing starch granule size. During nonisothermal crystallization, the dependency of the relative degree of crystallinity on time was described by the Avrami equation. The addition of starch decreased the overall crystallization rate of PP, which was attributed to an increase in the activation energy of crystallization under nonisothermal conditions according to the Kissinger equation. An increase in starch granule size of starch would increase the crystallization activation energy of PP and consequently decrease its crystallization rate. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 484–492, 2004     

Water absorption and dimensional stability of short kenaf fiber‐filled polypropylene composites treated with maleated polypropylene

The purpose of this research was to investigate the water absorption behavior and associated dimensional stability of kenaf‐polypropylene‐filled (PP/KF) composites. Composites with different fiber loadings, ranging from 0 to 40 wt %, were prepared with a twin‐screw extruder followed by hot press molding. The influence of the compatibilizer was also studied for PP/KF composite with 5 wt % maleated PP (MAPP). Water absorption testing was carried out at room temperature for 7 weeks. Tensile, flexural, and impact tests were also performed on control, wet, and re‐dried specimens. Increasing the fiber content resulted in higher water absorption and thickness swelling. The inferior mechanical properties of the wet composites were attributed to the effect of water, which deteriorates the interfacial properties of composites. On re‐drying, all properties were almost recovered because of the recovery of interfacial area as evident in scanning electron micrographs. Incorporation of the MAPP significantly improved the compatibility between the fiber and matrix and the mechanical properties of the composites compared with those without MAPP. It also diminished the water absorption as well as the related thickness swelling in the composites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

防紫外线细旦丙纶DTY生产工艺

研究了防紫外线细旦丙纶DTY生产工艺及其对纤维性能的影响。选择变形速度 40 0～5 0 0m/min ,拉伸倍数 1.4～ 1.6,D/Y比 1.60 ,第一热箱温度 ( 15 0± 5 )℃ ,第二热箱温度 12 0～ 13 0℃ ,纤维品质优良 ,一等品率达 95 % ,紫外线遮挡率大于 99%。