长玻璃纤维增强热塑性复合材料研究

分别制备了长玻璃纤维(LGF)、短玻璃纤维(SGF)增强聚苯硫醚(PPS)、聚酰胺(PA)6复合材料,研究了基体树脂粘度、口模类型、GF类型及喂料速度对复合材料力学性能、热性能的影响,利用扫描电子显微镜观察了注塑试样断面形貌及LGF在树脂基体中的分布状态.结果表明,基体树脂的粘度越大,对复合材料的力学性能影响越大;在相同GF含量下,LGF增强PPS、PA6复合材料的热变形温度普遍高于SGF增强PPS、PA6复合材料;LGF增强复合材料抵御裂纹开裂的能力提高.     

纤维增强CFP/PPS复合材料的制备与性能表征

以碳纤维(CF)和碳纤维粉末(CFP)为导电基体,制备出导电聚苯硫醚(PPS)复合材料.研究了复合材料的形貌、导电及力学性能.结果 表明,CFP能很好地分散在PPS复合材料内部,复合材料的表面电阻可达到103 Ω.同纯PPS复合材料相比,导电性能增加了四个数量级;一定范围内的CFP可以提高PPS复合材料的拉伸强度和冲击...     

PPS/PAI/CF复合材料摩擦磨损性能的研究

采用模压成型法制备了聚苯硫醚(PPS)/聚酰胺酰亚胺(PAI)合金及其碳纤维(CF)改性复合材料。测试分析了该复合材料的力学性能,并通过扫描电镜(SEM)对其摩擦磨损表面形貌进行了观察,探讨了复合材料的摩擦磨损性能;考察了PPS/PAI合金的最优配比及CF含量对PPS/PAI/CF复合材料性能的影响。结果表明:PAI的加入改善了PPS的力学性能,当PPS/PAI质量比为40/60时,PPS/PAI合金的力学性能最优;另外,CF的加入使PPS/PAI/CF填充复合材料的摩擦系数和磨损量大幅度下降,其中,当CF含量为30%时,PPS/PAI/CF填充复合材料的摩擦系数和磨损量较未填充PPS/PAI分别下降了66%和90%。     

纳米有机Si-聚苯硫醚复合材料的制备及表征

聚苯硫醚(PPS)是一种具有耐腐蚀、耐高温性能的半结晶热塑性聚合物,可被用作特种工程塑料.纯PPS通常具有质脆、易氧化的特性,不能直接使用,而纳米有机Si能够提高和改善聚苯硫醚(PPS)复合材料的力学性能和热力学性能.将纳米有机Si与聚苯硫醚(PPS)通过熔融共混挤出制得复合材料,利用SEM、DSC和力学检测等方法对P...     

玄武岩纤维增强聚苯硫醚的性能研究

采用熔融共混的方法制备了玄武岩纤维(BF)增强聚苯硫醚(PPS)复合材料。考察了BF用量对PPS/BF复合材料力学性能、热性能和结晶性能的影响,以及硅烷偶联剂和填料种类对PPS/BF复合材料力学性能的影响。结果表明:复合材料的拉伸强度、弯曲强度、冲击强度、负荷变形温度和分解温度均随BF用量的增加而提高;硅烷偶联剂KH560的加入可以改善复合材料的力学性能。在PPS/BF体系中添加玻璃纤维可以进一步提高材料的力学强度;在PPS/BF体系中添加甲基丙烯酸缩水甘油酯接枝乙烯-辛烯共聚物(POE-g-GMA)可以提高复合材料的无缺口冲击强度。通过差示扫描量热(DSC)测试发现,BF具有异相成核作用,可以促进树脂结晶并提高结晶速率。     

添加纳米白炭黑对锶铁氧体/PPS复合材料结构和力学性能的影响

采用熔融共混法,以纳米白炭黑为增韧剂改性锶铁氧体/聚苯硫醚(PPS)复合材料,分别通过简支梁摆锤冲击测试仪、万能试验机、差示扫描量热仪(DSC)和毛细管流变仪探究了不同添加量的纳米白炭黑对复合材料各项力学性能、熔融/结晶行为和流变行为的影响。结果发现,适量纳米白炭黑的添加可以改变PPS的结晶行为,显著提升复合材料的冲击强度和韧性,但也会导致复合材料的加工流动性下降。     

PPS对FEP／PPS复合材料结构与性能的影响

通过混炼工艺制备了聚全氟乙丙烯/聚苯硫醚(FEP/PPs)复合材料;研究了PPS用量对复合材料的微观结构、流动性能和力学性能的影响.结果表明:PPS的加入能显著改善FEP/PPS复合体系的流动性能,但FEP/PPS复合体系的拉伸强度却随PPS用量的增加而逐渐降低.FEP/PPS复合体系流动性改善的机理是弥散分布的PPS液相小颗粒为FEP基体提供了较大的剪切变形空间,而复合材料拉伸强度的降低主要来自于两者界面较差的相容性.     

GF增强PPS/LCP复合材料的结晶行为和力学性能

液晶聚合物(LCP)的低熔接线强度是限制LCP应用的重要因素。为了提升LCP材料的力学性能,利用熔融加工方式制备不同LCP含量的聚苯硫醚(PPS)/LCP复合材料。DSC测试结果显示,当复合材料中LCP质量分数小于30%时,LCP的异相成核作用可提升PPS的结晶温度;随着LCP含量的进一步增加,PPS的结晶被抑制,复合材料的结晶温度逐渐降低。对于玻璃纤维(GF)增强PPS/LCP复合材料,随着LCP含量的增加,复合材料的拉伸强度和弯曲强度逐渐降低,弯曲弹性模量逐渐升高;而复合材料的熔接线拉伸强度随着LCP含量增加呈现出先降低后增加的趋势。微观结构观察显示,GF增强PPS/LCP复合材料的性能与PPS/LCP两相界面结合以及树脂/GF之间的界面结合作用较差有关。进一步利用乙烯-丙烯酸甲酯-甲基丙烯酸缩水甘油酯无规三元共聚物和环氧树脂提升GF增强PPS/LCP复合材料的界面相互作用,结果显示,环氧树脂可以显著提升复合材料的力学性能,同时复合材料的熔接线拉伸强度由31 MPa提升至70 MPa。     

石墨烯/聚醚砜和PIF加工对PPS性能影响

采用熔融挤出微型注塑方法制备了不同聚醚砜含量的石墨烯-聚醚砜-聚苯硫醚(PPS)复合材料,并通过对复合材料进行压力诱导流动成型(PIF),研究了聚醚砜含量和压力诱导流动成型对复合材料力学性能、微观结构和结晶的影响。结果表明:聚醚砜可以提高复合材料的冲击和拉伸性能,诱导PPS结晶促进成核,加速结晶作用。压力诱导流动可以使聚醚砜在聚苯硫醚基体中由球棒状变成扁平状,有效地起到增韧效果,提高了复合材料的力学性能。当聚醚砜的质量分数为30%时,复合材料冲击强度提高大约42%,拉伸强度提高11%。     

硅微粉改性PI/PPS/GF复合材料的制备及性能

采用双螺杆挤出机挤出工艺,制备了硅微粉改性聚酰亚胺(PI)/聚苯硫醚(PPS)/玻璃纤维(GF)复合材料。研究了PPS用量和硅微粉用量对PI/PPS/GF复合材料力学性能、动态力学性能、线膨胀系数和热性能的影响。复合材料拉伸强度、弯曲强度、悬臂梁无缺口冲击强度和初始储能模量随PPS用量增加而逐渐降低,线膨胀系数和熔体质量流动速率随之增加;材料力学性能随硅微粉用量增加先增加后减小,线膨胀系数和熔体质量流动速率随之增加而明显降低。差示扫描量热仪(DSC)数据分析表明,PPS材料的加入使复合材料在230~240℃出现了结晶峰,硅微粉使初始结晶温度变高;复合材料的热稳定性能随着熔融硅微粉用量增加而增加。     

纳米SiO2对有机硅/聚苯硫醚复合材料相区大小及性能的影响

采用共混挤出的方法制得了力学性能优异的纳米Si02／有机硅／聚苯硫醚（PPS）纳米复合材料。用SEM研究了复合材料中纳米SiO2粒子的加入对有机硅／PPS共混物相区大小的影响。制得的复合材料中硅油为分散相,PPS为连续相,纳米Si02主要分布在硅油相以及硅油与PPS的两相界面处。纳米粒子的引入有利于减小硅油相的相区尺寸,调节两相粘度匹配,促进两相混合,从而达到了提高材料力学性能的目的。     

原位聚合法制备高透光率韧性PMMA复合树脂的研究

采用原位聚合法制备PMMA/P(BA-St)/PMMA三层韧性有机玻璃复合树脂,分子设计方法的使用,保持了材料的透明性。考察了韧性粒子粒径、橡胶相组成以及橡胶含量对材料力学和光学性能的影响。借助透射电镜、扫描电镜和动态光散射方法对复合胶乳粒子以及所制材料的形态结构进行了表征。结果表明:橡胶相的折光指数对材料的透光率有明显影响,橡胶相玻璃化温度越低,越有利于增韧。     

短芳纶纤维增强聚苯硫醚复合材料的性能

研究了短芳纶纤维增强ＰＰＳ／ＰＥＫ－Ｃ复合材料树脂体系的力学性能。主要讨论了短芳纶纤维的长度、含量及芳纶纤维的表面处理方法和压制温度对复合材料体系力学性能的影响。结果表明：纤维的长度和含量对力学性能有显著影响,在相同纤维含量下,纤维长度增加可使纤维末端数减少,减少了应力集中点,有利于拉伸强度和冲击强度的提高。芳纶纤维不需经过表面化学处理即与ＰＰＳ有良好的界面特性。随加工温度升高,复合材料冲击强度降低,拉伸强度提高     

Mechanical properties and flammability of polycarbonate alloys containing nanosize additives

Different organic–inorganic composite particles [montmorillonite/poly(butyl acrylate) (PBA)/poly(methyl methacrylate) (PMMA), SiO₂/PBA/PMMA, and CaCO₃/PBA/PMMA] were synthesized by emulsion polymerization. Furthermore, polycarbonate (PC) alloys were prepared via the doping of these composite particles into PC with a twin‐screw extruder. The structure, mechanical properties, and flammability of the PC alloys were studied in detail. Although the tensile modulus of PC decreased a little, the flexibility and impact resistance were improved by the addition of these composite particles. This result was attributed to the fact that the composite particles were well dispersed in the PC matrix, with a cocontinuous phase formed between the particles and PC. In addition, the combustion behavior of the PC alloys, compared with that of the pure PC, resulted from a ceramic‐like char that formed on the surface of the PC alloys during burning. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Reinforcing network structure: Analysis of the phase morphology and mechanical properties of polymer blends [poly(methyl methacrylate)/poly(ϵ‐caprolactone)] with the addition of a third polymer [poly(vinyl chloride)]

A thin matrix network structure of poly (vinyl chloride), poly(?‐caprolactone), and in situ formed poly(methyl methacrylate) (PMMA) was synthesized. The structure was observed with scanning electron microscopy. The dissolution test suggested that a simple method to generate high rates of crosslinking at a lower temperature was obtained. The relationship of the phase morphology and mechanical properties of the blends was studied, and a reinforced material of PMMA was obtained. The obvious increase in the mechanical properties and the reinforcing effect were attributed to the formation of crosslinking and the network structure in the blend. The glass‐transition temperatures, obtained by DSC, suggested confined thermal behavior of PMMA chains restricted by a crosslinking system. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

PMMA/ATO纳米复合材料的结构与导电性能

采用溶液共混的方式制备了聚甲基丙烯酸甲酯/纳米掺锑二氧化锡(PMMA/ATO)复合材料,分析了复合材料的微观相态结构及导电性能,并对复合材料的物理机械性能及热性能进行了研究.结果表明:经过钛酸酯偶联剂处理的纳米ATO在PMMA基体中分散良好,在含量较低的情况下即可获导电性能良好的复合材料;当纳米ATO的质量分数为5%时,复合材料具有良好的物理机械性能;纳米ATO在PMMA基体中起到了交联点的作用,使其玻璃化转变温度随着ATO的增加而升高,从而改善了PMMA的耐热性能.     

PVDF/PMMA/Basalt fiber composites: Morphology,melting and crystallization,structure, mechanical properties,and heat resistance

This paper is to study the effect of basalt fiber on morphology, melting and crystallization, structure, mechanical properties, melting and crystallization of PVDF/PMMA composites using scanning electron microscopy (SEM), X‐ray, differential scanning calorimeter (DSC), dynamical mechanical analysis (DMA), etc. Basalt fiber may disperse well in PVDF/PMMA matrix and form compact fiber network, and this makes tensile and flexural strength of fiber reinforced PVDF/PMMA composites get to the maximum value of 62 and 102 MPa, respectively. However, the mechanical properties begin to decrease when basalt fiber content exceeds 20 wt %. The α and β phase of PVDF can coexist in composites, and basalt fiber and PMMA can induce β phase of PVDF. The melting temperature of PVDF in composites is kept unchanged, but the degree of crystallinity of composites increases as basalt fiber content increase, and then declines when fiber content exceeds 20%. The DSC results confirm that the nucleation ability of PVDF is enhanced by basalt fiber. Also, the heat resistance of PVDF/PMMA composite is improved from 133 to 146.1°C due to basalt fiber. The DMA shows that basalt fiber increases the storage modulus of PVDF/PMMA composite, and the loss peak of PMMA increases from 116.1 to 130°C. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40494.     

Multiphase materials with lignin: 9. Effect of lignin content on interpenetrating polymer network properties

A series of lignin-based polyurethane/poly(methyl methacrylate) (LPU/PMMA) interpenetrating polymer networks (IPNs) were prepared by solvent casting in film form. While the LPU/PMMA ratio remained constant (1:1), the properties of the LPU were controlled by varying the composition of the hydroxypropyl lignin polyol via chain extension with propylene oxide. An increase in the lignin content of the polyol resulted in a decrease in the molecular weight between crosslinks (M_c) and change in the morphology of the LPU/PMMA composite. This effect resulted in the transition from a two-phase material to a single-phase material when the (true) lignin content of the composite rose above 25 wt%. As the lignin content increased, the strength properties of the composites increased. The dynamic mechanical, thermal and ultimate mechanical properties of the entire series of IPNs could be explained by dual phase continuity.     

Mechanical and tribological properties of PA66/PPS blend. III. Reinforced with GF

Based on previous work, 70 vol % PA66/30 vol % PPS blend was selected as a matrix, and the PA66/PPS blend reinforced with different content of glass fiber (GF) was prepared in this study. The mechanical properties of PA66/PPS/GF composites were studied, and the tribological behaviors were tested on block‐on‐ring sliding wear tester. The results showed that 20–30 vol % GF greatly increases the mechanical properties of PA66/PPS blend. When GF content is 20 vol %, the friction coefficient of composite is the lowest (0.35), which is decreased by 47% in comparison with the unfilled blend. The wear volume of the GF‐reinforced PA66/PPS blend composite decreases with the increase of GF content. However, the wear‐resistance is not apparently improved by the addition of GF in the experimental range for comparison with unfilled PA66/PPS blend. The worn surface and the transfer film on the counterface were examined by scanning electron microscopy (SEM). The observations revealed that the friction coefficient of composite depends on the formation and development of a transfer film. The wear mechanism involves polymer matrix wear and fiber wear. The former consists of melting wear and plastic deformation of the matrix, while the latter includes fiber sliding wear, cracking, rupturing, and pulverizing. The contributions of the matrix wear and the fiber wear determine the ultimate wear volume of PA66/PPS/GF composite. In addition, the abrasive action caused by the ruptured glass fiber is also a very important factor. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 523–529, 2006     

PMMA/棉花纤维素复合薄膜的制备及性能

为改善聚甲基丙烯酸甲酯(PMMA)的热性能和力学性能,以经过预处理的棉花纤维素为增强体,将PMMA与棉花纤维素溶液按不同比例混合,利用溶液浇铸法制备PMMA/棉花纤维素复合薄膜,并利用热重分析、透光性分析以及拉伸性能测试研究了不同棉花纤维素含量的PMMA/棉花纤维素复合薄膜的性能。结果表明,与PMMA薄膜相比,PMMA/纤维素复合薄膜的热稳定性和力学性能均有所提升,PMMA/纤维素复合薄膜的热分解温度提高8.3%;随着棉花纤维素含量从0增加到15%,拉伸强度从10.53 MPa提升到55.95 MPa,最高提升了431%。此外,复合薄膜的光透过率随着棉花纤维素含量的增加而降低。当棉花纤维素含量为7.5%时,复合薄膜不仅具有良好的力学性能,而且具有较高的透光率,综合性能较好。