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Rubber Composites (rubber + composite)
Kinds of Rubber Composites Selected AbstractsThermal and mechanical properties of dough modeling compound reinforced ethylene propylene diene monomer/silicon rubber compositesPOLYMER COMPOSITES, Issue 6 2006Weili Wu Ethylene propylene diene monomer (EPDM)/silicon rubber composite was prepared by adding dough-modeling compound (DMC). EPDM/silicon rubber is the matrix of the composite, and DMC is a disperse phase (reinforced phase). The morphology of the composite was studied by scanning electron microscopy, and it was found that the compatibility of DMC/EPDM/silicon rubber composite was good. The influence of the DMC and peroxide curing agents on the mechanical and thermal properties were studied. The results showed that the mechanical and thermal properties of the composite were best, when DMC/EPDM/silicon rubber was 80/25/75. The thermal properties of the composite prepared with added equivalent dicumyl peroxide was better than those with added benzoperoxide, but Shore A hardness and elongation at break are unchangeable. The integral properties of DMC reinforced EPDM/silicon rubber composite was much better than three raw materials. POLYM. COMPOS. 27:621,626, 2006. © 2006 Society of Plastics Engineers [source] Accelerator adsorption onto carbon nanotubes surface affects the vulcanization process of styrene,butadiene rubber compositesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2009A. De Falco Abstract The multiwalled carbon nanotubes (MWCNT) filled styrene,butadiene rubber (SBR) composites were prepared by incorporating MWCNT in a SBR/toluene solution and subsequently evaporating the solvent. These composites have shown a significant improvement in Young's modulus and tensile strength with respect to SBR gum without sacrificing high elongation at break. However, this improvement is less than expected at the higher filler content. Then, the influence of low concentrations of MWCNT on the vulcanization process of the SBR composites was studied by means of rheometer torque curves, swelling measurements, differential scanning calorimeter (DSC) analysis, and Fourier transform infrared (FTIR) spectroscopy. Also, their thermal degradation was studied by thermogravimetric analysis (TGA). It has been noticed that MWCNT affects the cure kinetics of SBR gum matrix reducing all parameters, i.e., the total heat rate and order of the reaction, scorch delay, maximum torque, and crosslink density. This effect increases as MWCNT content does, and it was attributed to the adsorption of the accelerator employed in the vulcanization (N -tert-butyl-benzothiazole-2-sulfenamide) onto the MWCNT surface. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] Thermal stability and ablation properties of silicone rubber compositesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2008Eung Soo Kim Abstract Effects of incorporation of clay and carbon fiber (CF) into a high temperature vulcanized (HTV) silicone rubber, i.e., poly(dimethylsiloxane) (PDMS) containing vinyl groups, on its thermal stability and ablation properties were explored through thermogravimetric analyses (TGA) and oxy-acetylene torch tests. Natural clay, sodium montmorillonite (MMT), was modified with a silane compound bearing tetra sulfide (TS) groups to prepare MMTS4: the TS groups may react with the vinyl groups of HTV and enhance the interfacial interaction between the clay and HTV. MMTS4 layers were better dispersed than MMT layers in the respective composites with exfoliated/intercalated coexisting morphology. According to TGA results and to the insulation index, the HTV/MMTS4 composite was more thermally stable than HTV/MMT. However, addition of CF to the composites lowered their thermal stability, because of the high thermal conductivity of CF. The time elapsed for the composite specimen, loaded with a constant weight, to break off after the oxy-acetylene flame bursts onto the surface of the specimen was employed as an index for an integrated assessment of the ablation properties, simultaneously taking into consideration the mechanical strength of the char and the rate of decomposition. The elapsed time increased in the order of: HTV < HTV/CF , HTV/MMTS4 < HTV/CF/MMTS4 , HTV/MMT < HTV/CF/MMT. This order was different from the increasing order of the thermal stability determined by TGA results and the insulation index. The decreased degree of crosslinking of the composites with MMTS4 compared with that of the composite with MMT may be unfavorable for the formation of a mechanically strong char and could lead to early rupture of the HTV/MMTS4 specimen. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Preparation of rubber composites from ground tire rubber reinforced with waste-tire fiber through mechanical millingJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2007Xin-Xing Zhang Abstract Composites made from ground tire rubber (GTR) and waste fiber produced in tire reclamation were prepared by mechanical milling. The effects of the fiber content, pan milling, and fiber orientation on the mechanical properties of the composites were investigated. The results showed that the stress-induced mechanochemical devulcanization of waste rubber and the reinforcement of devulcanized waste rubber with waste-tire fibers could be achieved through comilling. For a comilled system, the tensile strength and elongation at break of revulcanized GTR/fiber composites reached maximum values of 9.6 MPa and 215.9%, respectively, with 5 wt % fiber. Compared with those of a composite prepared in a conventional mixing manner, the mechanical properties were greatly improved by comilling. Oxygen-containing groups on the surface of GTR particles, which were produced during pan milling, increased interfacial interactions between GTR and waste fibers. The fiber-filled composites showed anisotropy in the stress,strain properties because of preferential orientation of the short fibers along the roll-milling direction (longitudinal), and the adhesion between the fiber and rubber matrix was improved by the comilling of the fiber with waste rubber. The proposed process provides an economical and ecologically sound method for tire-rubber recycling. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4087,4094, 2007 [source] The Effect of Silane Coupling Agents on the Viscoelastic Properties of Rubber BiocompositesMACROMOLECULAR MATERIALS & ENGINEERING, Issue 9 2006Maya Jacob Abstract Summary: This paper deals with the dynamic mechanical study of sisal/oil palm hybrid fiber reinforced natural rubber composites (at frequency 1 Hz) with reference to the role of silane coupling agents. Composites were prepared using sisal and oil palm fibers subjected to chemical modifications with different types of silane coupling agents. The silanes used were Silane F8261 [1,1,2,2-perfluorooctyl triethoxy silane], Silane A1100 [, -aminopropyltriethoxy silane] and Silane A151 [vinyl triethoxy silane]. It was observed that for treated composites, storage modulus and loss modulus increased while the damping property was found to decrease. Maximum E' was exhibited by the composite prepared from fibers treated with silane F8261 and minimum by composites containing fibers treated with silane A151. This was attributed to the reduced moisture absorbing capacity of chemically modified fibers leading to improved wetting. This in turn produced a strong interfacial interface giving rise to a much stiffer composite with higher modulus. Surface characterization of treated and untreated sisal fibers by XPS showed the presence of numerous elements on the surface of the fiber. Scanning electron micrographs of tensile fracture surfaces of treated and untreated composites demonstrated better fiber,matrix bonding for the treated composites. Scheme of interaction of silanes with cellulosic fibers. [source] Molecular transport of aromatic hydrocarbons through lignin-filled natural rubber compositesPOLYMER COMPOSITES, Issue 1 2007Thomas V. Mathew The diffusion and transport of organic solvents through lignin-filled natural rubber composites have been studied in the temperature range 25,45°C. The diffusion of aromatic solvents through these samples were studied with special reference to the effect of filler concentration, penetrant size, and temperature. Transport coefficients such as diffusion, permeation, and sorption coefficients were estimated. The van't Hoff relationship was used to determine the thermodynamic parameters. The first order kinetic rate constant has been evaluated. A correlation between theoretical and experimental sorption results was evaluated. POLYM. COMPOS., 28:15,22, 2007. © 2007 Society of Plastics Engineers [source] Thermally conductive silicone rubber reinforced with boron nitride particlePOLYMER COMPOSITES, Issue 1 2007Wen-Ying Zhou Thermally conductive silicone rubber used as elastomeric thermal pad is successfully developed with boron nitride powder as conductive filler. The effects of content and particle size of filler on the thermal conductivity and mechanical property of silicone rubber are investigated. The results indicate that the use of hybrid boron nitride with three different particle sizes at a preferable weight ratio gives silicone rubber better thermal conductivity compared with each boron nitride with single particle size at the same total filler content. Furthermore, scanning electron microscopy, differential scanning calorimeter, thermogravimetric, etc., are used to characterize the morphology, curing behavior, thermal stability, and coefficient of thermal expansion (CTE) of the silicone rubber composites. POLYM. COMPOS., 28:23,28, 2007. © 2007 Society of Plastics Engineers [source] Thermal and mechanical properties of dough modeling compound reinforced ethylene propylene diene monomer/silicon rubber compositesPOLYMER COMPOSITES, Issue 6 2006Weili Wu Ethylene propylene diene monomer (EPDM)/silicon rubber composite was prepared by adding dough-modeling compound (DMC). EPDM/silicon rubber is the matrix of the composite, and DMC is a disperse phase (reinforced phase). The morphology of the composite was studied by scanning electron microscopy, and it was found that the compatibility of DMC/EPDM/silicon rubber composite was good. The influence of the DMC and peroxide curing agents on the mechanical and thermal properties were studied. The results showed that the mechanical and thermal properties of the composite were best, when DMC/EPDM/silicon rubber was 80/25/75. The thermal properties of the composite prepared with added equivalent dicumyl peroxide was better than those with added benzoperoxide, but Shore A hardness and elongation at break are unchangeable. The integral properties of DMC reinforced EPDM/silicon rubber composite was much better than three raw materials. POLYM. COMPOS. 27:621,626, 2006. © 2006 Society of Plastics Engineers [source] Lead,Natural rubber composites as gamma radiation shields.POLYMER COMPOSITES, Issue 4 2002II: High concentration Natural rubber composites were prepared by the incorporation of different lead concentration, namely: 100, 300, 500, 1000, 1500 and 2000 phr to be used as gamma radiation shields. A non-linear dependence of the attenuation coefficient upon the lead concentration was observed for both 60Co and 137Cs as gamma radiation sources. Sample containing the ultimate lead concentration (2000 phr) and thickness 1 mm was found to have 0.336 mm and 0.383 mm lead equivalent for 60Co and 137Cs respectively. Electrical and mechanical properties of the investigated composites were also measured. [source] Organoclay,natural rubber nanocomposites synthesized by mechanical and solution mixing methodsPOLYMER INTERNATIONAL, Issue 11 2004MA López-Manchado Abstract This investigation describes two methods to obtain rubber composites based on natural rubber (NR) and organophilic layered silicates. In order to improve the exfoliation and compatibilization of the organoclays with the rubber matrix, a new approach which involves swelling of the organoclays with an elastomer solution prior to compounding has been used. The effect of the addition during swelling of a coupling agent, namely bis(trietoxysilylpropyl)tetrasulfan (TESPT), on the behaviour of the composites was also investigated. The results show that a low amount of organoclay (10 phr) significantly improves the properties of natural rubber. This suggests a strong rubber,organoclay interaction which is attributed to a high degree of rubber intercalation into the nanosilicate galleries, as was confirmed from X-ray diffraction. In addition, an ulterior improvement in the properties of the nanocomposites prepared by solution mixing is clearly observed, due to the better filler,rubber compatibility. An even further increase in the properties is observed by treating the silicate with a silane coupling agent. The silane functional groups modify the clay surface, thus reducing the surface energy, and consequently improving the compatibility with the rubber matrix. Copyright © 2004 Society of Chemical Industry [source] Polyamide 6/maleated ethylene,propylene,diene rubber/organoclay composites with or without glycidyl methacrylate as a compatibilizerJOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2008Lingyan Zhang Abstract Polyamide 6 (PA6)/maleated ethylene,propylene,diene rubber (EPDM- g -MA)/organoclay (OMMT) composites were melt-compounded through two blending sequences. Glycidyl methacrylate (GMA) was used as a compatibilizer for the ternary composites. The composite prepared through via the premixing of PA6 with OMMT and then further melt blending with EPDM- g -MA exhibited higher impact strength than the composite prepared through the simultaneous blending of all the components. However, satisfactorily balanced mechanical properties could be achieved by the addition of GMA through a one-step blending sequence. The addition of GMA improved the compatibility between PA6 and EPDM- g -MA, and this was due to the reactions between PA6, EPDM- g -MA, and GMA, as proved by Fourier transform infrared analysis and solubility (Molau) testing. In addition, OMMT acted as a compatibilizer for PA6/EPDM- g -MA blends at low contents, but it weakened the interfacial interactions between PA6 and EPDM- g -MA at high contents. Both OMMT and GMA retarded the crystallization of PA6. The complex viscosity, storage modulus, and loss modulus of the composites were obviously affected by the addition of OMMT and GMA. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] | ||||||||||