粘土/橡胶纳米复合材料老化性能研究

研究粘土 /SBR及粘土 /NR纳米复合材料的耐热氧老化和耐臭氧老化性能 ,并考察粘土 /SBR纳米复合材料的热失重和气体阻隔性。结果表明 ,粘土 /SBR纳米复合材料的耐热氧老化和耐臭氧老化性能均优于炭黑 /SBR复合材料 ;粘土 /NR纳米复合材料的耐热氧老化性能略优于炭黑 /NR复合材料 ,耐臭氧老化性能与炭黑 /NR复合材料相差不大 ;均匀分散的纳米粘土可提高橡胶的热稳定性和气体阻隔性 ,减缓氧及臭氧在橡胶中的扩散 ,降低橡胶分子链受攻击的几率 ,有利于提高橡胶耐热氧老化和耐臭氧老化性能     

一种白炭黑/粘土/橡胶纳米复合材料的制备方法

由北京化工大学申请的专利(公开号CN101704967A,公开日期2010-05-12)一种白炭黑/粘土/橡胶纳米复合材料的制备方法,提供了一种粘土/白炭黑/橡胶纳米复合材料的制备方法     

粘土/丁吡橡胶纳米复合材料的结构与性能研究

采用乳液共沉法制备粘土/丁吡橡胶纳米复合材料,并对其结构和性能进行研究。结果表明:粘土/丁吡橡胶纳米复合材料的整体分散效果较好,粘土用量对纳米复合材料的类型有影响;随着粘土用量的增大,粘土/丁吡橡胶混炼胶和硫化胶的储能模量逐渐增大,硫化胶的损耗因子随应变的增大而增大,邵尔A型硬度和100%定伸应力逐渐增大,气密性能提高;当粘土用量为20份时,复合材料的拉伸性能最佳。     

一种易混合高填充粘土/橡胶纳米复合材料的制备方法

由北京化工大学申请的专利(公开号CN 101851360A,公开日期2010-10-06)"一种易混合高填充粘土/橡胶纳米复合材料的制备方法",提供了一种易混合高填充粘土/橡胶纳米复合材料的制备方法:首先通过将橡胶乳液与粘土/水悬浮液共混,然后利用电解质溶液破乳形成1～100μm的絮凝颗粒,再利用水力旋流器分离、洗     

一种预处理粘土/橡胶纳米复合材料的制备方法

一种预处理粘土/橡胶纳米复合材料的制备方法     

橡胶纳米复合材料研究进展

橡胶纳米复合材料因其优异的性能而目前材料科学研究的热点。本文论述了橡胶／粘土、橡胶／纳米SiO2、氢化NBR／丙烯酸金属盐、橡胶／纳米炭黑和白炭黑、橡胶／纳米纤维等橡胶基纳米复合材料的制备方法、机理、力学性能、工业应用领域等,讨论了层状硅酸盐粘土的表面修饰,提出了插层剂的选择原则,评价了各种合成技术的优缺点及工业价值,提出了橡胶纳米复合材料的发展趋势。     

复合粘土/橡胶纳米复合材料的短评(2)

<正>6橡胶/粘土纳米复合材料的制备目前,用以下方式制备橡胶/粘土纳米复合材料:1)溶液混合;2)胶乳混合;3)熔融聚合物的直接插层(熔体插层)。6.1溶液混合该方法是干橡胶与有机改性粘土在适当的溶剂中溶解或溶解后在适当的溶剂中混合在一起。在除去溶剂之前可先加入硫化剂,但它们通常在部分或全部溶剂除去之后与插层材料混合,然后在特定温度下硫化。对溶液混合来说,有机粘土分散在溶剂中,它同时也是橡胶的良溶剂。通过搅拌,溶剂蒸发,得到了橡胶/有机粘土纳米复合材料。Hwang等人用甲基乙基酮将NBR与二甲基脱氢牛脂季铵盐改性粘土混合。溶剂蒸发后,在     

橡胶的纳米增强及纳米复合技术

分析了橡胶增强中几个主要因素的作用和地位,认为粒径是橡胶增强的第一要素,粒径因素包括部分表面活性因素和结构性因素,纳米增强是同效增强的必要条件,并指出炭黑和白炭黑增强橡胶属于纳米复合材料范畴。综述了橡胶基纳米复合材料的研究进展,包括炭黑和白炭／橡胶纳米复合材料、粘土／橡胶纳米复合材料、原位二氧化硅／橡胶纳米复合材料、丙烯酸金属盐／橡胶纳米复合材料、纤维／橡胶纳米复合材料等。总结了第一种复合材料所涉     

改性石墨烯/粘土/天然橡胶纳米复合材料的结构与性能

大量研究表明,纳米填料的表面效应、大的比表面积以及纳米粒子本身对基体的强界面效应对橡胶纳米复合材料性能的提升具有极大的帮助。本研究以天然橡胶(NR)为基体材料,采用乳液法制备石墨烯/粘土/NR纳米复合材料。讨论了石墨烯、粘土的用量对复合材料的物理机械性能的影响。结果表明,当粘土用量为3.0 phr时,随着石墨烯添加量的增加,石墨烯/粘土/NR纳米复合材料的力学性能和耐磨性先升高,然后略有下降。当石墨烯添加量为1.0 phr时,复合材料的拉伸强度提高了33.3%,而阿克隆磨耗体积下降了22.7%。     

椰油酰胺丙基甜菜碱改性粘土/丁腈橡胶纳米复合材料的结构与性能

采用椰油酰胺丙基甜菜碱（CAB）对粘土进行改性,制备改性粘土/丁腈橡胶（NBR）纳米复合材料,并对其结构与性能进行研究。结果表明：改性后的粘土层间距增大,NBR与改性粘土形成了有序插层型纳米复合材料,不同种类的有机粘土在橡胶基体中均达到纳米分散;随着CAB用量的增大,改性粘土在橡胶基体中的分散变好,填料网络结构增强,复合材料的硬度、拉伸强度、拉断伸长率、撕裂强度增大,定伸应力变化不大;与有机粘土I.30P和I.44P相比,当粘土阳离子交换容量与CAB的摩尔比为1∶5时,改性粘土对NBR的补强效果最佳。     

Preparation and characterization of polystyrene–clay nanocomposites by free‐radical polymerization

The polymerizable cationic surfactant, vinylbenzyldimethylethanolammouium chloride (VBDEAC), was synthesized to functionalize montmorillonite (MMT) clay and used to prepare exfoliated polystyrene–clay nanocomposites. The organophilic MMT was prepared by Na⁺ exchanged montmorillonite and ammonium cations of the VBDEAC in an aqueous medium. Polystyrene–clay nanocomposites were prepared by free‐radical polymerization of the styrene containing intercalated organophilic MMT. Dispersion of the intercalated montmorillonite in the polystyrene matrix determined by X‐ray diffraction reveals that the basal spacing is higher than 17.6 nm. These nanocomposites were characterized by differential scanning calorimetry (DSC), transmission electron micrograph (TEM), thermal gravimetric analysis (TGA), and mechanical properties. The exfoliated nanocomposites have higher thermal stability and better mechanical properties than the pure polystyrene. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1370–1377, 2002     

An emphasis on dynamic mechanical properties of novel stilbene containing copolymer/organo-MMT nanocomposites fabricated via in situ interlamellar copolymerization

The objective of the present study is to synthesis and characterize the novel functional stilbene containing copolymer-clay nanocomposites, make clear the influence of organo-clay on peculiarities of the nanocomposites and emphasis on the dynamic mechanical properties. For this purpose, poly(acrylamide-co-trans-stilbene)-organo-MMT [poly(AAm-co-Stb)-O-MMT] nanocomposites were synthesized by in situ interlamellar solution copolymerization with organically modified montmorillonite (O-MMT) clay due to its superior properties gives to copolymer. The effect of different amounts of O-MMT clay incorporation to the nanocomposite structure and properties of copolymer/O-MMT clay nanocomposites were characterized by X-ray diffraction (XRD), Attenuated Total Reflectance-Fourier Transform Infrared, Thermogravimetric Analysis, Differential Scanning Calorimeter, Dynamic mechanic analysis (DMA) methods. XRD analysis showed the basal spacing of the O-MMT increased in nanocomposites and this indicated that the intercalation of the copolymer chain into the O-MMT interlayer performed and nanocomposites were obtained successfully. Additionally, copolymer/O-MMT nanocomposites exhibited improved thermal properties at higher temperatures than the pristine copolymer. DMA results enlightened the viscoelastic properties of synthesized materials. DMA results indicated that obtained nanocomposites have higher mechanical strength because of the interaction/compatibility in between copolymer chains and O-MMT. In the light of these results, this work has introduced new perspectives on design, fabrication and viscoelastic properties of certain organo-clay copolymer nanocomposites for the synthesis of new materials and potential industrial applications.     

Synthesis and properties of polystyrene–clay nanocomposites via in situ intercalative polymerization

Organophilic montmorillonite (MMT) was prepared by ion exchange between Na⁺ ions in the clay and twin benzyldimethyloctadecylammonium bromine cations in an aqueous medium. The organophilic MMT particles were easily dispersed and swollen in styrene monomer. Polystyrene–MMT nanocomposites were prepared by the free‐radical polymerization of styrene containing dispersed clay. The intercalation spacing in the nanocomposites and the degree of dispersion of these composites were investigated with X‐ray diffraction and transmission electron microscopy, respectively. The nanocomposites had higher weight‐average molecular weights, lower glass‐transition temperatures, and better thermal stability (the decomposition temperature was improved by ca. 70°C) than the virgin polystyrene. The rheological behavior of the polystyrene–MMT nanocomposites was also studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 201–207, 2005     

Impact of nanoclay on physicomechanical and thermal analysis of polyvinyl alcohol/fumed silica/clay nanocomposites

Polyvinyl alcohol (PVA)/fumed silica/clay nanocomposites are prepared via solution intercalation by exploiting phase separation based on the bridging of particles by polymer chains. PVA/fumed silica/clay nanocomposites are characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, and thermogravimetric analysis. Mechanical properties are determined by universal testing machine. From FTIR results, it indicates that IR spectrum for PVA/fumed silica/clay nanocomposites, especially PVA/fumed silica/clay (1.30E) nanocomposites, is much broader than pure PVA and other clay nanocomposites. The better interfacial bonding between PVA/fumed silica/clay (1.30E) nanocomposites are reflected in the improvement of the mechanical properties as well as thermal stability. The surface area analysis result proves that the PVA/fumed silica/clay (1.30E) nanocomposites have higher surface area and pore volume with less pore size. With the addition of 1.30E clay to the composite system, the tensile strength and modulus had shown the highest values as well as higher activation energy for thermal decomposition. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41843.     

Fracture behavior of thermoplastic polyolefin/clay nanocomposites

A thermoplastic polyolefin (TPO) containing 70 wt % styrene–ethylene–butadiene‐styrene‐g‐maleic anhydride and 30 wt % polypropylene and its nanocomposites reinforced with 0.3–1.5 wt % organoclay were prepared by melt mixing followed by injection molding. The mechanical and fracture behaviors of the TPO/clay nanocomposites were investigated. The essential work of fracture (EWF) approach was used to evaluate the tensile fracture behavior of the nanocomposites toughened with elastomer. Tensile tests showed that the stiffness and tensile strength of TPO was enhanced by the addition of low loading levels of organically modified montmorillonite. EWF measurements revealed that the fracture toughness of the TPO/clay nanocomposites increased with increasing clay content. The organoclay toughened the TPO matrix of the nanocomposites effectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Rheological properties of poly(lactic acid) based nanocomposites: Effects of different organoclay modifiers and compatibilizers

Poly(lactic acid) (PLA) nanocomposites containing five types of organically modified, layered silicates and two elastomeric compatibilizers, namely ethylene‐glycidyl methacrylate (E‐GMA) and ethylene‐butyl acrylate‐maleic anhydride (E‐BA‐MAH), were prepared using a twin screw extruder. The morphologies of the nanocomposites were determined by X‐ray diffraction (XRD) and transmission electron microscopy (TEM), and the rheological properties of the melts were measured using small‐amplitude oscillatory shear. XRD revealed that the addition of E‐GMA to the binary nanocomposites resulted in higher compatibility between the organoclay nanoplatelets and the polymer matrix. TEM showed that all of the nanocomposites contained mixed dispersed structures, involving tactoids of various sizes, as well as intercalated and exfoliated organoclay layers. Rheological properties were found to be affected by the differences in the compatibility between the organoclays and the polymer matrix, and by the addition of the compatibilizer. Organoclay types that resulted in high level of dispersion exhibited higher values of complex viscosity compared to that of neat PLA. The addition of E‐GMA introduced a solid‐like rheological behavior at low frequencies. All of the nanocomposites had similar rheological behavior at high frequencies. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42915.     

Water-assisted extrusion of polypropylene/clay nanocomposites: A comprehensive study

Water-assisted extrusion process has been used to successfully prepare polypropylene (PP)/clay nanocomposites with high degree of clay delamination and markedly improved rheological, thermal and mechanical properties. PP-graft-maleic anhydride (PP-g-MA)-based nanocomposites and masterbatches were synthesized from untreated clay and organoclay, respectively, and fully characterized. The effects of using high-shear rates and water injection during the melt-compounding were examined. A mechanism explaining the formation of such nanocomposites is then proposed. The best clay dispersion and properties improvements of PP-g-MA/organoclay nanocomposites and masterbatches were obtained using high-shear rates and water injection (synergy effect). PP-based nanocomposites were then synthesized by dilution of PP-g-MA-based masterbatches into neat PP. For comparison, nanocomposites were also prepared by a one-pot process where PP, PP-g-MA and organoclay are directly melt-blended with or without water injection. The nanocomposites prepared by dilution into PP of a masterbatch prepared through water-assisted extrusion showed the highest clay dispersion and consequently the best thermal, mechanical and rheological properties.     

Mechanical properties and structures of dicyanate–clay nanocomposites

Dicyanate–clay nanocomposites comprising a dicyanate resin and a type of organically modified clay were prepared and characterized, and their thermomechanical properties were investigated. The organically modified clay had silicate layers of nanometer size intercalated with an organic modifier, which improved the compatibility between the clay and organic materials, such as dicyanate resins. Dynamic mechanical analysis was performed to investigate the thermomechanical properties of the dicyanate–clay nanocomposites containing various amounts of the clay. The storage modulus of the nanocomposites below their glass‐transition temperatures slightly increased with increasing clay content. The glass‐transition temperature of the dicyanate–clay nanocomposites increased with increasing clay content. The nanostructures of the dicyanate–clay nanocomposites were characterized by transmission electron microscopy and X‐ray diffraction analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2629–2633, 2003     

Preparation and characterization of Polyethylene/Clay/Silver nanocomposites using functionalized polyethylenes as an adhesion promoter

The performance of Polyethylene (PE)/Clay/Silver nanocomposites is dependent to a great extent on the properties of filler–matrix interface. To improve the interfacial properties in PE/Clay/Silver composites, different types of compatibilizers or adhesion promoters were introduced. The compatibilization provided by maleic anhydride (MA), itaconic acid (IA) and 2-[2-(dimethylamine)-ethoxy] ethanol (DMAE) functionalized PEs for forming PE-based nanocomposites was studied and compared. IA was grafted into PE by melt mixing to obtain PEgIA (compatibilizer 1), thereafter, PEgIA and PEgMA (compatibilizer 2) were reacted with DMAE also by melt mixing to obtain PEgI-DMAE (compatibilizer 3) and PEgM-DMAE (compatibilizer 4). These compatibilizers were reacted using ultrasound with a solution of AgNO₃ 0.04 M and ethylene glycol. Ammonium hydroxide was added in a ratio of 2:1 M with respect to silver nitrate. These silver coated compatibilizers were mixed with PE and with a quaternary ammonium modified montmorillonite clay (Nanomer I28E), thus forming the different hybrid PE/Clay/Silver nanocomposites. FTIR confirmed the formation of these compatibilizers. All the DMAE compatibilized nanocomposites had better filler (clay and silver) dispersion and exfoliation. XRD, oxygen and water transmission rate as well as antimicrobial properties attained showed that the PEgI-DMAE produced the better dispersed PE, clay and silver nanocomposites. The obtained nanocomposites showed enhanced barrier properties and outstanding antimicrobial properties against bacteria, E. coli. PEgI-DMAE offers an outstanding capability for preparing nanocomposites with highly exfoliated and dispersed filler into the PE matrix that offers a new option for obtaining hybrid nanocomposites with enhanced properties to be used in packaging applications.