氮化铝/氧化石墨烯对环氧树脂胶黏剂导热性能的影响

使用硅烷偶联剂KH-560对氮化铝进行了表面改性,并以其为导热填料,环氧树脂为基体,制备了氮化铝/环氧树脂导热胶黏剂。采用FTIR、SEM、TG、热常数分析仪对导热胶黏剂进行了表征。结果表明:改性后硅烷偶联剂分子成功接枝在氮化铝表面。改性后,氮化铝与环氧树脂的界面粘结力增强,热稳定性和导热性均得到明显改善。当氮化铝质量为导热胶黏剂质量的70%时,改性氮化铝/环氧树脂热胶黏剂的导热系数为2.24W/(m·K),而未改性氮化铝/环氧树脂的导热系数仅为1.73W/(m·K)。为进一步提高其导热性能,制备了改性氮化铝/氧化石墨烯/环氧树脂导热胶黏剂,当改性氮化铝和氧化石墨烯的质量分数分别为50%和3%时,导热胶黏剂导热系数为3.05 W/(m·K)。     

PE-LD/硅烷偶联剂改性石墨烯复合薄膜的制备及性能表征

将硅烷偶联剂KH-560接枝到氧化石墨烯上制得KH-560改性氧化石墨烯（KGO）,通过水合肼还原得到KH 560改性石墨烯（KG）,最后将KG和石墨烯（G）分别与低密度聚乙烯（PE-LD）熔融共混、中空吹塑成PE LD/KG复合薄膜和PE-LD/G复合薄膜。对样品的结构、形貌、光学性能、阻透性能、热性能和力学性能等进行表征。结果表明,KH-560成功接枝到KG上;KG无序度增加,KG的层间距比G增加约80 %;KG在PE-LD中分散均匀,团聚较少;G对复合薄膜的光学性能和阻透性能的增强效果优于KG;而KG对复合薄膜的热性能和力学性能的改善明显优于G;当KG的含量为0.5 %（质量分数,下同）时,PE-LD/KG复合薄膜的结晶度和弹性模量分别比纯PE-LD薄膜提高了8.4 %和63.9 %。     

环氧树脂/改性SiC复合材料的制备及性能

采用硅烷偶联剂KH-560和丙烯酰胺对SiC进行表面改性,将其添加到环氧树脂中制备环氧树脂/改性SiC复合材料.采用傅里叶变换红外光谱仪、X射线衍射仪以及接触角测试仪探究改性SiC的性能,并对复合材料的性能进行测试.结果表明:SiC表面带有憎水基团,与环氧树脂相容性提高;SiC用量为环氧树脂质量的20％时,拉伸强度和弯...     

端氨基超支化聚硅氧烷接枝氧化石墨烯改性环氧胶粘剂的研究

利用硅烷偶联剂KH-550制备了端氨基超支化聚硅氧烷,并将其接枝到氧化石墨烯表面,通过FT-IR、XRD和TEM等手段表征了接枝结构。再将其添加到环氧树脂中,制备出改性环氧胶粘剂。通过TEM、DMA、高温剪切强度以及90°剥离强度测试,研究了接枝氧化石墨烯对环氧胶粘剂的性能影响。研究结果表明:改性氧化石墨烯加入后环氧树脂的玻璃化转变温度有明显提高;当功能化氧化石墨烯的添加量为0.20%时,高温剪切强度和常温剥离强度较改性前分别提高了18%和129%,表明接枝改性氧化石墨烯的引入能够在一定程度上提高环氧树脂的韧性和耐温性。     

碳纳米材料表面改性碳纤维及在环氧树脂中的应用

以N,N-二甲基甲酰胺为溶剂,通过超声的方法分别制备含多壁碳纳米管(MWCNTs)或石墨烯纳米片(GnP)的碳纳米材料表面改性剂,采用浸渍法对预处理碳纤维(CF)(去浆CF)进行改性使碳纳米材料均匀涂覆在纤维表面上,然后采用手糊成型及热压成型工艺制备环氧树脂(EP)/改性CF复合材料,利用扫描电子显微镜和电子万能试验机分析碳纳米材料表面改性剂制备条件对CF表面形貌、复丝拉伸性能的影响,在此基础上,选择各自的最佳表面改性剂制备条件,对比了含MWCNTs或GnP的表面改性剂改性CF对复合材料力学性能的影响。结果表明,碳纳米材料在表面改性剂中的分散状态直接影响CF表面碳纳米材料分布的均匀性和复合材料的性能。超声时间为2h的含MWCNTs表面改性剂和GnP质量分数为0.5%的含GnP表面改性剂对CF的改性效果较好,相应复丝的拉伸强度与去浆CF复丝相比分别提高了59.4%和70.2%,而相应复合材料的弯曲强度相对于EP/去浆CF复合材料分别提高了11.2%和41.1%,层间剪切强度分别提高了35.8%和71.3%。     

含碳纳米管上浆剂改性碳纤维及其复合材料的研究

利用上浆法和含多壁碳纳米管(MWCNT)的上浆剂对碳纤维(CF)进行表面改性,采用手糊成型和热压成型工艺制备CF复合材料,借助扫描电子显微镜(SEM)和电子万能试验机研究MWCNT对CF表面形貌及复合材料力学性能的影响。结果表明,MWCNT在上浆剂中的分散状态会直接影响MWCNT在CF表面分布的均匀性、对CF的改性效果及CF复合材料的力学性能。质量分数为0. 5%MWCNT上浆剂对CF的改性效果较好,经0. 5%MWCNT上浆剂改性CF复丝的拉伸强度与去浆CF相比提高了70. 8%,改性CF复合材料的弯曲强度和层间剪切强度与去浆CF复合材料相比分别提高了42. 8%和72. 9%。     

羽毛球拍用碳纤维的表面改性与性能研究

为了对碳纤维进行表面接枝改性处理以增强碳纤维与环氧树脂间的结合力,提升碳纤维的综合力学性能并应用于羽毛球拍中。以亚临界水作为反应介质将三聚氰胺接枝到羽毛球拍用碳纤维表面,研究了反应时间对接枝改性碳纤维的表面形貌、接触角/表面能、单丝拉伸强度、界面剪切强度和冲击韧性的影响。结果表明,上浆处理后碳纤维表面不会有上浆剂残留,但是碳纤维纵向仍然可见加工沟槽,当三聚氰胺接枝改性时间延长至25min及以上时,碳纤维纵向沟槽有所变浅,且由于三聚氰胺在碳纤维上的聚集使得碳纤维表面粗糙度增大,局部可见块状聚集。经过三聚氰胺介质改性的碳纤维的接触角都小于接枝改性前、表面能都大于接枝改性前,随着接枝反应时间的延长,改性碳纤维的接触角不断减小。三聚氰胺接枝改性处理后碳纤维的单丝拉伸强度相较于接枝改性前有不同程度的降低,且随着反应时间的延长,单丝拉伸强度呈现先减小后增大的特征。随着三聚氰胺接枝改性时间的延长,CF-W-t的界面剪切强度、裂纹形成功、拓展功和冲击功呈现逐渐增加的趋势。将三聚氰胺接枝到羽毛球拍用碳纤维表面可以增强碳纤维的综合力学性能。     

多壁碳纳米管/玻璃纤维/环氧树脂界面粘结特性研究

本文对一种多壁碳纳米管进行表面酸化和胺化改性处理,通过超声波分散制备碳纳米管/玻璃纤维/环氧树脂单丝复合试样,采用单丝断裂法研究碳纳米管对玻璃纤维/环氧树脂界面粘结特性的影响。实验结果表明,加入碳纳米管后环氧树脂弯曲性能提高,单丝复合体系的拉伸应力-应变曲线在屈服点之后产生波动。通过比较纤维断点数-应变曲线、偏光下纤维断点形貌以及断口形貌SEM图像发现,对于玻璃纤维体系,加入硅烷偶联剂KH560后,碳纳米管可明显提高玻璃纤维/环氧界面粘结强度,并以胺化碳管改性体系影响最为显著。     

聚碳酸亚丙酯/埃洛石纳米管复合材料共混改性研究

采用硅烷偶联剂γ-缩水甘油醚氧丙基三甲氧基硅烷(KH-560)对埃洛石纳米管(HNTs)进行表面改性以改善其与聚碳酸亚丙酯(PPC)的相容性,并将改性的HNTs(m-HNTs)和未改性的HNTs分别与PPC通过熔融共混法制备了复合材料。通过傅里叶变换红外光谱仪、流变仪、热失重分析仪对m-HNTs和PPC复合材料进行了测试。结果表明,硅烷偶联剂KH-560成功接枝到HNTs上,接枝率达到26%;m-HNTs在PPC中分散更均匀,m-HNTs可以很好地减缓PPC自身的降解,有效提高复合材料的热稳定性,PPC/m-HNTs复合材料的拉伸强度显著高于未改性的复合材料。     

偶联剂对 PPS/PA66/T-ZnOw 复合材料力学性能的影响

采用硅烷偶联剂KH-560和钛酸酯偶联剂TM-38S对四针状氧化锌晶须(T-ZnOw)进行表面改性,制备了相应的聚苯硫醚(PPS)尼/龙(PA)66/T-ZnOw复合材料,研究了两种偶联剂及其复合体系对T-ZnOw表面改性效果和相应复合材料力学性能的影响,并利用扫描电子显微镜对复合材料的断面形态进行了观察。结果表明,钛酸酯偶联剂TM-38S对T-ZnOw的表面改性效果要优于硅烷偶联剂KH-560;两种偶联剂均提高了复合材料的拉伸强度、断裂伸长率和缺口冲击强度,但对复合材料的弯曲强度影响不大。其中TM-38S改性T-ZnOw与PPS/PA66复合后所得材料的力学性能优于KH-560改性T-ZnOw的材料。两种偶联剂的复合体系虽然可以弥补KH-560副反应对T-ZnOw表面改性的不利影响,但对改善复合材料力学性能的协同作用不明显。     

稀土偶联剂WOT对纳米碳酸钙/SBR复合材料性能的影响

采用稀土偶联剂WOT对纳米碳酸钙进行表面改性,通过机械共混法制备纳米碳酸钙/SBR复合材料,研究其性能,并与硅烷偶联剂KH-560进行对比。结果表明,与硅烷偶联剂KH-560相比,稀土偶联剂WOT改性复合材料的加工性能较优,拉伸强度和拉断伸长率较高,稀土偶联剂WOT的最佳用量为1.6份;两种偶联剂均能改善纳米碳酸钙在SBR胶料中的分散性,提高复合材料的动态力学性能。     

铁尾矿砂基环氧树脂透水材料力学性能及界面特性研究

利用固体废弃物制备透水材料是海绵城市发展新方向,而力学性能差成为固废基透水材料应用的难点之一。为解决该问题,设计了一类用铁尾矿砂作为骨料,环氧树脂作为胶凝材料的聚合物透水材料,研究了环氧树脂含量对透水材料力学性能和透水性能的影响,并探讨了纳米SiO₂、TiO₂、Al₂O₃和硅烷偶联剂KH-560等有机-无机材料对透水材料力学性能的影响。结果表明:当环氧树脂质量分数为6%时,可以得到兼顾力学性能和透水性能的透水材料,抗压、抗折强度和透水速率分别为17.5 MPa、5.3 MPa和1.12 mm/s;同时,当纳米SiO₂、TiO₂、Al₂O₃的添加量分别为环氧树脂的3%、4%、4%(质量分数)时,对透水材料力学性能的提升分别为33.1%、30.5%、28.6%,其原因是纳米粒子在透水材料受压过程中会吸收树脂基体中的部分能量,抑制或消除树脂中微裂纹的扩散;当硅烷偶联剂KH-560的添加量为环氧树脂的0.9%(质量分数)时,透水材料的强度可提升36.5%。SEM和FTIR分析表明,硅烷偶联剂KH-560对改善铁尾矿砂与环氧树脂界面具有显著作用。该研究对研发高性能的固废基透水材料具有重要意义。     

Interfacial improvement of carbon fiber-reinforced methylphenylsilicone resin composites with sizing agent containing functionalized carbon nanotubes

A liquid sizing agent containing multiwall carbon nanotubes (MWCNTs) was prepared for carbon fiber (CF) reinforced methylphenylsilicone resin (MPSR) composite applications. In order to improve the dispersion of MWCNTs in the sizing agent and interfacial adhesion between CF and MPSR, MWCNTs and CF were functioned by the chemical modification with tetraethylenepentamine (TEPA) used as a MPSR curing agents. The CF before and after the sizing treatment-reinforced MPSR composites were prepared by a compression molding method. The microstructures, interfacial properties, and impact toughness of CF were systematically investigated. Experimental results revealed that a thin layer of MPSR coating containing functionalized MWCNTs (MWCNT-TEPA) was uniformly grafted onto the surface of CF. The sized CF-reinforced MPSR composite showed simultaneously remarkable enhancement in the interlaminar shear strength and impact toughness. Meanwhile, the tensile strength of CF had no obvious decrease after sizing treatment. In addition, the interfacial reinforcing and toughening mechanisms were also discussed. We believe that the facile and effective method in preparing multifunctional fibers provides a novel interface design strategy of carbon fiber composites for different applications.     

Improving the interfacial properties of carbon fiber–epoxy resin composites with a graphene-modified sizing agent

We successfully prepared a graphene-modified carbon fiber (CF) sizing agent with good dispersity and stability by dispersing reduced graphene oxide (RGO) into an emulsion-type sizing agent. RGO was obtained by the reduction of graphene oxide (GO) with the help of gallic acid. The influence of the graphene-modified sizing agent on the interfacial properties of the CF–epoxy resin composites was investigated with microbond testing and the three-point bending method. The results show that optimized interfacial properties were achieved when the size of the modified graphene was less than 1 μm, the content of RGO was 20 ppm, and the pH value of the sizing agent was 10.5. The interfacial shear strength of the composites reached 92.3 MPa, which was 29.6% higher than that of the composites with unmodified CFs. Compared with commercial-CF-fabric-reinforced composites, the interlaminar shear strength of the composites treated with the RGO-modified sizing agent increased by 21.5%. Both the interfacial and interlaminar failure morphologies of the composites were examined with scanning electron microscopy (SEM). The results show that a large amount of residual resin adhered to the surfaces of the CFs treated with the RGO-modified sizing agent; this indicated good interfacial properties between the CFs and the resin matrix. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47122.     

硫酸钡表面改性及其在PVC中的性能研究

使用γ-氨丙基三乙氧基硅烷(KH-550)、γ-缩水甘油醚氧丙基三甲氧基硅烷(KH-560)、γ-(甲基丙烯酰氧)丙基三甲氧基硅烷(KH-570)以及硬脂酸(SA)对沉淀硫酸钡(BaSO4)粉末进行表面处理,并使用接触角测试仪、管式炉和红外光谱仪对改性BaSO4进行表征。进一步将改性BaSO4添加到聚氯乙烯(PVC)中,研究了它们对PVC/BaSO4复合材料基本力学性能的影响,并分析了复合材料冲击截面的断裂面形貌。结果表明,改性BaSO4的表面接触角显著增大,红外光谱显示有基团峰出现,质量损失率明显变大,其中SA的改性效果最佳,接触角为134.5°,质量损失率为4.65%。和添加未改性BaSO4的PVC复合材料相比较而言,添加改性BaSO4的PVC复合材料的拉伸性能和撕裂性能均有所增强,硬度变化不大,其中,总体上SA的表面改性效果最佳,PVC/BaSO4复合材料的拉伸强度、撕裂强度和邵氏D硬度分别达到28.68 MPa、151.03 N/mm、70.2。复合材料断裂表面的扫描电子显微镜分析表明,经过改性的BaSO4粉末在复合材料中的分散性变得更好。     

Preparation and mechanical properties researches of silane coupling reagent modified β-silicon carbide filled epoxy composites

The β-silicon carbide (β-SiC) micro particles modified by silane coupling reagent of γ-glycidoxy propyl trimethoxy silane (KH-560) were employed to prepare β-silicon carbide/epoxy resin (SiC/EP) by blending-casting moulding method to acquire polymer composites with high mechanical properties. Mechanical tests demonstrate that, both the flexural and impact strength of the composites increased firstly with the increasing content of SiC, but decreased with excessive addition of SiC. When the mass fraction of SiC was 10%, the mechanical properties of SiC/EP composites were maximum. Meantime, the use of SiC particles modified by KH-560 significantly enhanced mechanical properties of SiC/EP composites. The surface performance of SiC was characterized and analyzed by XPS, FTIR and TGA. The results indicated that a chemical bonding formed between KH-560 and SiC, and a layer of organic single molecule membrane formed on the surface of SiC. And the maximum mass fraction of KH-560 coated on the surface of SiC was about 2.62%.     

Enhanced Thermal Conductivity of Epoxy Composites with MWCNTs/AlN Hybrid Filler

To further improve the thermal conductivity of epoxy resin, the multi-walled carbon nanotube/aluminum nitride (MWCNTs/AlN) hybrid filler was employed to prepare thermal conductivity MWCNTs/AlN/epoxy composite by casting process, and the silane coupling reagent of γ-glycidoxy propyl trimethoxy silane(KH-560) was also used to functionalize the surface of MWCNTs and/or AlN. Results revealed that, the thermal conductivity of epoxy resin was improved remarkably with the addition of MWCNTs/AlN hybrid filler, a higher thermal conductivity of 1.04 W/mK could be achieved with 29 wt% MWCNTs/AlN hybrid filler (4 wt% MWCNTs +25 wt% AlN), about 5 times higher than that of native epoxy resin. And the epoxy composite with 29 wt% MWCNTs/AlN hybrid filler possessed better thermal conductivity and mechanical properties than those of single 5 wt% MWCNTs or 40 wt% AlN. The thermal decomposition temperature of MWCNTs/AlN/epoxy composite was increased with the addition of MWCNTs/AlN hybrid filler. For given filler loading, surface treatment of MWCNTs and/or AlN by KH-560 exhibited a positive effect on the thermal conductivity of epoxy composite.     

高强度耐湿热老化室温硫化硅橡胶的研制

以107硅橡胶为基胶,甲基三丁酮肟基硅烷为交联剂,纳米活性碳酸钙及气相法白炭黑为补强填料,氨基硅烷与环氧基硅烷复配使用,制得高强度耐湿热老化的室温硫化硅橡胶。探讨了107硅橡胶的黏度、交联剂甲基三丁酮肟基硅烷的用量、纳米活性碳酸钙的表面处理剂用量及比表面积、偶联剂的种类对硅橡胶耐湿热老化性能的影响。较佳配方为:100份黏度20 000 mPa.s的107硅橡胶、8份甲基三丁酮肟基硅烷、80份表面处理剂用量为30 g/kg、比表面积为16 m2/g的纳米碳酸钙、2.5份KH-792与KH-560按量之比1∶1复配的硅烷偶联剂。以此配方制得的RTV硅橡胶的外观为白色膏状,邵尔A硬度50度、拉伸强度2.44 MPa、拉断伸长率430%;将硫化7天后的硅橡胶试片,置于温度85℃,相对湿度85%的恒温恒湿试验箱中老化1 000 h后,其邵尔A硬度38度、拉伸强度1.98 MPa、拉断伸长率650%。