丁腈橡胶/功能化氧化石墨烯复合材料的研究

用硅烷偶联剂KH590对氧化石墨烯进行功能化改性,得到的功能化氧化石墨烯再通过乳液共混和机械共混等工艺制备了丁腈橡胶/功能化氧化石墨烯复合材料.表征分析了功能化氧化石墨烯的结构和表面形态,研究了丁腈橡胶/功能化氧化石墨烯复合材料的机械性能.结果 显示,与氧化石墨烯相比,功能化氧化石墨烯的亲水性和表面形态均发生了较大变化...     

氧化石墨烯改性粉末丁腈橡胶-环氧树脂复合材料的研究

采用三辊研磨分散技术制备了氧化石墨烯改性粉末丁腈橡胶-环氧树脂三元复合材料,探讨了氧化石墨烯不同用量对复合材料机械性能的影响.结果 表明,当氧化石墨烯用量为0.3％时,复合材料的无缺口冲击性能和抗弯曲性能最好;随氧化石墨烯用量的增加,复合材料的热变形温度有所提升,但硬度变化不明显.     

氧化石墨烯改性粉末丁腈橡胶-环氧树脂复合材料的研究

采用三辊研磨分散技术制备了氧化石墨烯改性粉末丁腈橡胶-环氧树脂三元复合材料,探讨了氧化石墨烯不同用量对复合材料机械性能的影响。结果表明,当氧化石墨烯用量为0.3%时,复合材料的无缺口冲击性能和抗弯曲性能最好;随氧化石墨烯用量的增加,复合材料的热变形温度有所提升,但硬度变化不明显。     

功能化还原氧化石墨烯/天然橡胶导热复合材料的性能研究

采用2-巯基苯并咪唑(防老剂MB,以下简称MB)对氧化石墨烯(GO)进行还原及功能化,同时与采用抗坏血酸(VC)对GO进行还原对比,分别制得MB还原氧化石墨烯(rGO-MB)和VC还原氧化石墨烯(rGO-VC),并采用胶乳共混法制备rGO-MB/NR和rGO-VC/NR复合材料,对其性能进行研究。结果表明:MB成功还原了GO,MB接枝到了GO上;与rGO-VC/NR复合材料相比,rGO-MB/NR复合材料具有较低的Payne效应和较高的结合胶含量,拉伸强度和导热性能均明显提高。     

HDPE/功能化石墨烯复合材料制备及性能研究

氧化石墨烯(GO)具有较高的比表面积,层间距大,表面拥有丰富的官能团,可以很好地分散到聚合物中,但GO导电性差。研究对GO进行还原和表面修饰,以改善石墨烯和HDPE的相容性。采用熔融混炼法制备了HDPE/石墨烯复合材料,结合力学性能、导电性能、微观结构测试,考察不同HDPE/石墨烯复合材料的导电阈值,分析影响复合材料导电性的因素,进而得出较优化的制备工艺。研究发现石墨烯添加量为7.5%时,导电通路开始形成,当石墨烯含量达到7.5%时,拉伸强度提升22.14%,拉伸模量提升21.19%。     

用一步法原位制备氢化丁腈橡胶/还原氧化石墨烯纳米复合材料

将氢化丁腈橡胶(HNBR)与石墨烯二维纳米材料(GO)共混以提高其导电和导热性能,采用乳液一步法还原制备了HNBR/还原氧化石墨烯(RGO)纳米复合材料。结果表明,丁腈橡胶(NBR)乳液中分子链的碳碳双键和GO经水合肼/过氧化氢/硫酸铜催化体系产生的活性中心二酰亚胺被同时进行加氢和还原,这在改善HNBR性能的同时简化了RGO纳米复合材料的制备工艺,制备过程没有毒性大的有机溶剂。HNBR/RGO纳米复合材料的氢化度为61%,I_D/I_G为1. 36,说明NBR/GO中分子链双键和GO经一步法得到还原。采用一步法可将RGO在HNBR基质中均匀分散。HNBR/RGO纳米复合材料的力学性能和热性能因RGO的存在得以大幅度改善。     

氧化石墨烯基抗菌复合材料的研究进展

氧化石墨烯以其独特的抗菌机制,在多个领域发挥着巨大的作用。基于氧化石墨烯的结构特点,阐述其抗菌机理,分析影响抗菌性能的关键因素,总结氧化石墨烯基复合材料的功能化修饰策略及研究进展。通过分析已有的氧化石墨烯基复合材料的应用,提出当前研究局限性和发展前景展望,为未来开发新型抗菌复合材料提供思路。     

氧化石墨烯/羧基丁腈橡胶纳米复合材料的制备及其耐有机溶剂渗透性能的研究

采用改进Hummers法制备氧化石墨烯（GO）,并以聚乙烯亚胺为“桥接分子”制备GO/羧基丁腈橡胶（XNBR）纳米复合材料,考察GO/XNBR纳米复合材料的微观形貌、力学性能和耐有机溶剂渗透性能。结果表明：GO与XNBR基体结合良好且分散均匀;GO/XNBR纳米复合材料的拉伸强度由纯XNBR胶料的3.9 MPa提高到7.2 MPa(GO用量为0.7份),提高了约1.8倍;随着GO用量增大,GO/XNBR纳米复合材料对有机溶剂的耐渗透时间明显延长。     

氧化石墨烯填充羧基丁腈橡胶复合材料的热稳定性及降解动力学

采用改进的Hummers法制备了不同氧化程度的氧化石墨烯(GO),并采用乳液混合法制备了GO/羧基丁腈橡胶(XNBR)复合材料,表征了GO的微观结构及其在复合材料中的分散状况,考察了GO的氧化程度对复合材料热稳定性的影响,分别采用Kissinger法和Ozawa法计算了复合材料的热分解活化能。结果表明,GO表面含有羧基、羰基和环氧基的含氧基团,氧化程度随着氧化剂高锰酸钾用量的增加而提高;GO氧化程度的提高可以有效改善GO在XNBR基体中的分散效果及复合材料的热稳定性,但是氧化程度过高会使热稳定性下降;采用Kissinger法和Ozawa法计算得到的热分解活化能虽不相同,但其大小顺序与GO氧化程度一致。     

端羟基丁腈橡胶功能化氧化石墨烯增韧环氧胶粘剂性能研究

以4,4'-二环己基甲烷二异氰酸酯(HMDI)为偶联剂,制备了端羟基丁腈橡胶(HTBN)功能化的氧化石墨烯,并对功能化产物进行了结构和力学性能表征.研究结果表明:成功制备了功能化产物;将5份HTBN与0.25份的氧化石墨烯进行功能化反应并用于环氧胶粘剂增韧时,改性体系的韧性得到明显改善.断裂伸长率和冲击强度较未改性环氧...     

Observation of mechanical percolation in functionalized graphene oxide/elastomer composites

We have covalently functionalized graphene oxide (GO) with octadecylamine (ODA) to form GO–ODA. This material can be dispersed in tetrahydrofuran (THF) and subsequently formed into composites with polymers such as thermoplastic polyurethane (TPU). We have characterized the mechanical properties of composites of GO–ODA in TPU. No increase in stiffness was observed at loading levels below 2.5 vol%. Reinforcement appeared to start sharply at this volume fraction and subsequently increased as a power law with increasing volume fraction. This behavior is typical of percolation and shows that the low-strain stress is not increased until the functionalized graphene flakes form a percolating network. Slightly different behavior is observed for properties related to material failure. The ultimate tensile strength increased linearly with graphene content up to the percolation threshold before subsequently falling off. Similarly the strain at break was constant below the percolation threshold but fell off dramatically above it. This work shows the importance of network formation in the reinforcement of elastomeric materials.     

氧化石墨烯/密胺树脂导电复合材料的制备与性能研究

采用的改进的Hummers法和组合剥离技术制备了氧化石墨烯(GO),并以氧化石墨烯、甲醛溶液、三聚氰胺为原料,采用原位合成技术制备石墨烯/密胺树脂导电复合材料(GO/MF)及含有水合肼的氧化石墨烯/密胺树脂复合材料(GO/MF+N_2H_4),并对其结构、热稳定性和导电性等进行研究分析。试验结果表明:GO/MF+N_2H_4试样的热稳定性最佳,氧化石墨烯的加入,提高了密胺树脂材料的导电性,且添加质量分数0.9%GO的GO/MF+N_2H_4试样出现导电临界值,体积电阻率达到1.5×10~4Ω·m,为制备具有抗静电性能和导电性能的密胺树脂新型复合材料提供一定的基础理论参考。     

Kevlar oligomer functionalized graphene for polymer composites

Kevlar oligomer functionalized graphene (FGS) was prepared by simple grafting of amino-terminated Kevlar oligomer on graphene oxide (GO) followed by reducing with hydrazine hydrate. The incorporation of FGS shows pronounced effect on the host polymers. High-level reinforcement of both PMMA and PI is observed with low content of FGS (≤0.2 wt %), in this lower loading range, the tensile modulus and strength of composites increase almost linearly as a function of the adding amount of FGS. But no further improvement is obtained as the content of FGS further increased (>0.2 wt %). The mechanism under the reinforcement effect against the FGS loadings is discussed based on the morphological characterizations of the composites. The thermal properties of the composites were also investigated. The glass transition temperature and thermal stability of PMMA were dramatically increased even with the addition of only a small amount of FGS.     

Thermal conductivity and structure of non-covalent functionalized graphene/epoxy composites

Non-covalent functionalization was used to functionalize graphene nanosheets (GNSs) through π–π stacking of pyrene molecules with a functional segmented polymer chain, which results in a remarkable improvement in the thermal conductivity of GNS-filled polymer composites. The functional segmented poly(glycidyl methacrylate) containing localized pyrene groups (Py-PGMA) was prepared by atom transfer radical polymerization, and Py-PGMA was characterized by nuclear magnetic resonance spectroscopy. Raman spectra, X-ray photoelectron spectroscopy and thermogravimetric analysis reveal the characteristics of Py-PGMA–GNS. Differential scanning calorimetry indicated that the functional groups on Py-PGMA–GNSs can generate covalent bonds with the epoxy matrix, and further form a cross-linked structure in Py-PGMA–GNS/epoxy composites. The Py-PGMA on the GNS surface not only plays an important role to facilitate a homogeneous dispersion in the polymer matrix but also improves the GNS–polymer interaction, which results in a high contact area. Consequently, the thermal conductivity of integrated Py-PGMA–GNS/epoxy composites exhibited a remarkable improvement and is much higher than epoxy reinforced by multi-walled carbon nanotubes or GNSs. The thermal conductivity of 4 phr Py-PGMA–GNS/epoxy has about 20% (higher than that of pristine GNS/epoxy) and 267% (higher than pristine MWCNT/epoxy).     

NBR/革屑复合材料性能研究

将制革工艺中的削匀革屑（LS）与丁腈橡胶（NBR）混炼并压板制备成复合材料（NBR/LS）,通过测定复合材料物理力学性能考察工艺条件对材料性能的影响。分别对NBR纯胶和NBR/LS复合材料的热性能进行了表征。测试结果表明：NBR/LS复合材料制备中压板时间、温度和革屑含量均对NBR/LS复合材料有较大影响;最佳力学性能出现在压板时间为30 min,温度为150℃,革屑用量为15份的工艺条件下;革屑的加入使得NBR的玻璃化转变温度（Tg）从-33.6℃升高至-31.0℃,复合材料的tanδ峰值和损耗模量明显降低;NBR/LS复合材料比NBR纯胶有较好的热稳定性能。     

聚吡咯/氧化石墨烯复合材料的制备及电化学性能研究

分别采用物理球磨混合法、化学原位聚合法和化学原位聚合-还原法制备了聚吡咯/氧化石墨烯混合物、聚吡咯/氧化石墨烯(PPy/GO)和聚吡咯/还原氧化石墨烯(PPy/RGO)复合材料。通过三电极测试其电化学性能(循环伏安、恒流充放电和交流阻抗)。结果表明,通过化学原位聚合法制备的PPy/GO(304. 5 F/g)比电容远高于物理混合(16 F/g)和聚吡咯/还原氧化石墨烯(126. 4 F/g)。化学法原位聚合法制备PPy/GO最佳条件是冰浴条件下和加入表面活性剂对羟基苯磺酸钠。并通过X射线衍射(XRD)和扫描电子显微镜(SEM)对化学原位制备的PPy/GO组成、结构和形貌进行了表征。     

一步水热法合成铜改性的介孔γ-Al_2O_3及其吸附脱硫性能研究

采用一步水热合成法,以Al(NO3)3为铝源,P123为模板剂,Na OH、Na2CO3和K2CO3分别为沉淀剂,Cu(NO3)2为铜源,制备出负载铜的金属有序介孔γ-Al2O3,并运用N2吸附-脱附和XRD等技术对其结构进行表征,同时探讨了铜改性的介孔γ-Al2O3对模型燃油中的噻吩的吸附性能。结果表明,这3种沉淀剂都能制备出比表面积大(>226 m2/g),孔径分布中心为3.3 nm,孔体积为0.27⁰.35 cm3/g的负载铜的介孔γ-Al2O3,且样品都保持了较好的介孔结构。样品对模型燃油中噻吩的吸附脱硫性能表明,用Na OH作为沉淀剂且负载铜的介孔γ-Al2O3样品对噻吩的吸附性能较好,原因在于此样品具有较大的比表面积且铜在此样品中的分散性较好。     

ZnO/石墨烯复合材料的制备及性能研究

本文将采用溶胶-凝胶法制备纳米ZnO和通过Hummers法制备的石墨烯进行简单的一步超声复合,得到ZnO/石墨烯复合材料。利用XRD、TEM以及紫外可见分光光度计对所制备的ZnO和石墨烯样品进行测试表征,并以亚甲基蓝的降解效率来评价ZnO/石墨烯复合材料的光催化活性能。研究表明:ZnO/石墨烯的光催活性较纯氧化锌提高了4倍有余,当石墨烯质量比为15%时,ZnO/石墨烯的光催化活性最强。