聚偏氟乙烯/石墨烯发泡复合材料制备及电磁屏蔽性能

使用熔融共混的方法制备不同含量石墨烯纳米片(GNPs)的聚偏氟乙烯(PVDF)复合材料,并采用超临界二氧化碳作为发泡剂对其进行釜压发泡,制备PVDF复合材料泡沫.研究了PVDF复合材料的断面结构、结晶行为、熔融行为、流变行为和发泡行为,并研究了PVDF复合材料及其泡沫的电导率和电磁屏蔽性能.结果表明,GNPs质量分数为...     

聚偏氟乙烯/类基体基团修饰石墨烯导热复合材料研究

采用含类基体基团的乙烯基三甲氧基硅烷修饰氧化石墨烯(GO),再用"一锅法"将其还原得到功能化石墨烯(F-GE),通过溶剂浇注法制备出界面性能优良的聚偏氟乙烯导热复合材料(PVDF/F-GE).利用红外光谱仪(FTIR)、扫描电子显微镜(SEM)、热导率测试仪、电子拉力试验机对复合材料的改性状态、微观形貌、导热性能和力学...     

氧化石墨烯/聚偏氟乙烯复合膜研究

采用Hummers法合成氧化石墨,通过超声分散法获得氧化石墨烯,并使用溶剂蒸发法制备了氧化石墨烯/聚偏氟乙烯复合膜。采用透射电子显微镜(TEM)、红外光谱(FTIR)以及X射线衍射(XRD)对氧化石墨烯的形貌和结构进行分析,对复合膜进行扫描电子显微镜(SEM)、机械性能以及导热系数的分析测定。结果表明,本实验中制备的氧化石墨烯含有大量的含氧基团;氧化石墨烯能够均匀的分散在复合膜中,并且会增加复合膜的机械性能和导热性能。复合膜的导热系数随w(氧化石墨烯)的增加而呈现先增大后减小的趋势,当w(氧化石墨烯)为0.4%时,导热系数达到最大值。     

聚偏氟乙烯—ABS复合材料

前言ABS 树脂具有优良的机械性能,良好的加工性,而且价格低廉,因此广泛用于家用电器、办公机械、汽车等行业;它的缺点是耐紫外线、耐药品性、耐污染性较差,因此不适合作室外使用的材料。聚偏氟乙烯(PVdF)不但具有优异的耐候性,而且耐药品性、耐磨耗性、耐污染性良好。本文介绍的 PVdF-ABS 复合材料是指 PVdF-ABS 的共挤出层压板,国外称 KA 板。由于它兼有 PVdF 的特点,因此改善了 ABS 塑料的耐候性、耐药品性和耐污染性,从而扩大了它的用途。     

聚偏氟乙烯复合材料的制备和性能

综述了β相聚偏氟乙烯（PVDF）材料制备工艺的作用,重点探讨了拉伸,超声处理,掺杂,复合作用,极化,衬底作用,溶剂作用,水合盐等作用对其β相PVDF材料制备影响,介绍了其特点及其在压电传感中存在的不足,并对其进行了总结和展望。     

俄产聚偏氟乙烯树脂性能及用途

介绍了俄罗斯生产的聚偏氟乙烯Ф-2和改性聚偏氟乙烯Ф-2М的性能、加工成型方法及其用途。Ф-2和Ф-2М分别具有CH2—CF2m和(CH2—CF2)n—(CF2—CF2)m分子结构的结晶聚合物,其加工成的制品具有着优异的综合性能。该聚合物属于热塑性含氟高分子材料,可采用模压、挤出和压铸等通用的常规方法进行加工成型。     

聚偏氟乙烯/三氧化二锑复合材料的制备及其激光标记性能研究

将三氧化二锑(Sb₂O₃)引入聚偏氟乙烯(PVDF)基体中,制备具有近红外激光响应性的PVDF/Sb₂O₃复合材料。探究Sb₂O₃的含量、粒径和激光参数(激光电流、激光扫描速率)对PVDF/Sb₂O₃复合材料激光标记性能的影响。结果表明：当Sb₂O₃含量为3%,粒径为0.2μm,激光电流为11 A,扫描速率为600 mm/s,对PVDF/Sb₂O₃复合材料的激光标记综合效果最佳。激光炭化的程度直接影响,复合材料的表面颜色深度与粗糙度。激光标记产生的无定型碳物质,是构成激光标记图案的主要组成部分。     

聚偏氟乙烯共混隔膜的制备与性能

以乙二醇二甲基丙烯酸酯和丙烯腈为单体,合成了聚合物poly(AN-co-PEGDMA),然后与聚偏氟乙烯(PVDF)共混,制备了不同poly(AN-co-PEGDMA)含量的PVDF/poly(AN-co-PEGDMA)共混隔膜,利用X射线衍射、扫描电子显微镜(SEM)、差示扫描量热对共混隔膜的性能进行表征。结果表明,随着poly(AN-co-PEGDMA)含量的增加,PVDF/poly(AN-co-PEGDMA)的玻璃化转变温度逐渐提高,衍射峰的谱峰强度逐渐降低,隔膜的结晶度降低。SEM结果显示,随着poly(AN-co-PEGDMA)含量的增加共混隔膜的孔隙变大,有利于电解液的有效吸收。通过对PVDF/poly(AN-co-PEGDMA)共混隔膜电导率、吸液率的测定,表明在poly(AN-co-PEGDMA)质量分数为30%时,制得的共混隔膜的性能较佳。在此基础上,对共混隔膜构建的聚合物锂离子电池的电化学稳定窗口、电池容量和循环性能进行测试,其电化学稳定窗口为0～4.7 V(vs Li+/Li),放电电容为1.433～1.151 mAh,可以满足商业使用要求,具有广阔的应用前景。     

氧化石墨烯含量对聚偏氟乙烯超滤膜结构和性能的影响

采用浸没沉淀相转化法制备不同氧化石墨烯添加量改性聚偏氟乙烯复合超滤膜,并使用扫描电镜和接触角测量仪表征膜片断面结构及亲水性;借助超滤杯测定不同膜片的纯水通量,模拟污染后的水通量恢复率及水通量衰减率;对复合膜对大肠杆菌的抑制性也进行了表征.结果表明:当氧化石墨烯添加量为1％时,改性膜的指状孔结构明显而且较粗,水通量达到最...     

三维石墨烯/聚氨酯复合材料的制备与特性

以氧化石墨烯(GO)为网络骨架的前驱体,通过水热还原、冷冻干燥制备了石墨烯气凝胶(GA);再以聚氨酯(PU)为复合材料的填充体,调节PU软硬度与流动性并真空浸渍气凝胶GA,两步法制备出互咬型三维石墨烯/聚氨酯(3DGP)复合材料。利用SEM、Raman、FTIR对GO、GA、3DGP的结构与形貌进行了表征,并采用TGA-DSC和自制压阻测试平台分析热稳定性和压阻特性。结果表明:6 g/L GO水溶液在还原剂乙二胺(EDA)作用下,GO片层间相互连接形成规整蜂窝状三维网络结构,其孔径约0.8mm,3DGP中PU与GA能很好地咬合;三维网络骨架的连续性为热运输载体声子提供了良好通道,使得3DGP热稳定性能显著提升,失重率5%时温度较PU提升了45℃;具有低迟滞性(8.7%)并且在压阻测量区间表现出两种压阻效应。     

基于聚偏氟乙烯复合结构色材料的制备与性能

以聚偏氟乙烯(PVDF)为黏结剂，将其填充于三维PS@SiO₂光子晶体中，锁定PS@SiO₂微球组装的有序阵列，成功构建了结构稳定且柔韧的新型PVDF/PS@SiO₂结构色材料。使用纳米粒度与电位分析仪对PS@SiO₂微球的多分散性指数以及Zeta电位进行了测试，采用SEM、TEM、固体紫外-可见光谱仪、预置式色牢度摩擦仪及拉伸测试仪对PVDF/PS@SiO₂结构色材料的形貌、光学性质及稳定性进行了表征和测试。结果表明，该结构色材料在摩擦测试100次后，结构保持稳定，颜色稳定存在。同时材料易于图案化，具有优异的抗拉伸性能和柔性，材料的拉伸断裂应力达到22.28 MPa，断裂应变为28.49%，在卷曲100次后，依旧保持微观结构稳定。     

石墨烯/二氧化钛复合材料的制备及催化性能研究

以石墨粉和钛酸四丁酯为原料,通过水热法一步合成了石墨烯/二氧化钛复合材料.采用XRD和SEM对该复合物进行了表征,并研究了光照条件、石墨烯含量、煅烧温度、光催化时间和pH等因素对聚丙烯酰胺降黏性能的影响.实验结果表明:在石墨烯/二氧化钛复合材料中,二氧化钛纳米颗粒均匀地分散在石墨烯层上;当在石墨烯质量分数为10％、煅烧温度为450℃、pH为6～7、光催化30 min等条件下,石墨烯/二氧化钛复合材料在紫外光下对聚丙烯酰胺的光催化降黏率能达到96％以上.     

Preparation and characterization of graphene composites with conducting polymers

We report a new route for preparing electro‐conductive composites based on reduced graphene oxide (RG‐O) and poly(3,4‐ethylenedioxythiophene) (PEDOT). The composites were prepared by in situ polymerization of EDOT in aqueous mixture containing RG‐O platelets modified with poly(sodium 4‐styrenesulfonate) (PSS). In the synthetic process, PSS molecules stabilize RG‐O in the aqueous phase and function as a polymerization template to hybridize PEDOT chains along RG‐O platelets. Compared with the RG‐O platelets, the resulting composites show an enhanced electrical conductivity of 9.2 S cm^?1 with good thermal stability. Copyright © 2011 Society of Chemical Industry     

Phase transformation and dielectric properties of polyvinylidene fluoride/organic-montmorillonite nanocomposites fabricated under elongational flow field

Compounding montmorillonite (MMT) with polymorphic polyvinylidene fluoride (PVDF) by melt intercalation method can induce the crystal phase transformation of PVDF, which is of great significance to obtain the electroactive PVDF. In this research, PVDF/Organic-Montmorillonite (OMMT) nanocomposites were prepared by a novel vane mixer, which was dominated by the elongational flow field in the whole plasticizing. The dispersion of OMMT, the crystal phase transformation of PVDF, and the resulting properties of nanocomposites were experimentally studied. The results of TEM and WAXD evidenced that homogeneous dispersion and desirable intercalation structure of OMMT were formed in the PVDF matrix under the effect of the elongational flow field. WAXD, FTIR, and DSC tests demonstrated that large amounts of β-phase of PVDF was formed due to the introduction of OMMT. The intercalation structure of OMMT and the crystal transformation of PVDF increased the dielectric constant and piezoelectric properties of nanocomposites, while the dielectric loss still maintained at a very low level. Finally, the effect of unique ''double-layer peeling'' mechanism of OMMT on the properties of nanocomposites was discussed.     

Mechanical properties of graphene nanoplatelet/epoxy composites

Because of their high‐specific stiffness, carbon‐filled epoxy composites can be used in structural components in fixed‐wing aircraft. Graphene nanoplatelets (GNPs) are short stacks of individual layers of graphite that are a newly developed, lower cost material that often increases the composite tensile modulus. In this work, researchers fabricated neat epoxy (EPON 862 with Curing Agent W) and 1–6 wt % GNP in epoxy composites. The cure cycle used for this aerospace epoxy resin was 2 h at 121°C followed by 2 h at 177°C. These materials were tested for tensile properties using typical macroscopic measurements. Nanoindentation was also used to determine modulus and creep compliance. These macroscopic results showed that the tensile modulus increased from 2.72 GPa for the neat epoxy to 3.36 GPa for 6 wt % (3.7 vol %) GNP in epoxy composite. The modulus results from nanoindentation followed this same trend. For loadings from 10 to 45 mN, the creep compliance for the neat epoxy and GNP/epoxy composites was similar. The GNP aspect ratio in the composite samples was confirmed to be similar to that of the as‐received material by using the percolation threshold measured from electrical resistivity measurements. Using this GNP aspect ratio, the two‐dimensional randomly oriented filler Halpin–Tsai model adjusted for platelet filler shape predicts the tensile modulus well for the GNP/epoxy composites. Per the authors' knowledge, mechanical properties and modeling for this GNP/epoxy system have never been reported in the open literature. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Preparation and characterization of polyvinylidene fluoride hollow fiber membranes for ultrafiltration

Polyvinylidene fluoride (PVDF) hollow fiber membranes were prepared using the solvent spinning method. N,N-dimethylacetamide was the solvent and ethylene glycol was employed as non-solvent additive. The effect of the concentration of ethylene glycol in the PVDF spinning solution as well as the effect of ethanol either in the internal or the external coagulant on the morphology of the hollow fibers was investigated. The prepared membranes were characterized in terms of the liquid entry pressure of water measurements, the gas permeation tests, the scanning electron microscopy, the atomic force microscopy, and the solute transport experiments. Ultrafiltration experiments were conducted using polyethylene glycol and polyethylene oxides of different molecular weights cut-off as solutes. A comparative analysis was made between the membrane characteristic parameters obtained from the different characterization techniques.     

聚偏氟乙烯/聚醚酰亚胺共混溶液的流变性能研究

采用二甲基乙酰胺(DMAc)为溶剂配制不同共混比的聚偏氟乙烯(PVDF)和聚醚酰亚胺(PEI)共混溶液,用锥板式黏度计研究了PVDF/PEI共混溶液的流变性能。结果表明:PVDF/PEI共混溶液表观黏度与剪切速率呈线性相关;当PVDF/PEI质量比为9/1时,共混溶液的零切黏度明显降低,非牛顿指数和黏流活化能出现极值;随着PEI含量的增加,黏流活化能急剧增大。     

金刚烷胺/氧化石墨烯复合材料的制备及其吸附性能

以氧化石墨烯和金刚烷为原料，通过水相合成法制备了金刚烷胺功能化氧化石墨烯复合材料A/GO，以FT-IR、XRD和XPS对A/GO进行了结构表征，并考察了A/GO对有机染料的吸附性能。结果表明，与氧化石墨烯相比，A/GO对甲基蓝（AB93）表现出高效吸附性，其吸附动力学和吸附等温模型分别符合拟二级动力学和Langmuir模型，理论最大吸附容量（qm）为1250.0 mg/g。热力学分析表明，A/GO吸附AB93是自发的放热过程。A/GO吸附AB93对盐（NaCl和KCl）表现出良好的耐盐性，而CaCl2能有效地促进A/GO吸附AB93。对于刚果红和AB93等的混合染料体系，A/GO能选择性吸附AB93。