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Natural rubber (NR), as a superior overall performance of renewable natural resources, has a high elasticity, high strength, high elongation and wear characteristics, widely used in aerospace, defense and military, heavy-duty vehicles, aircraft tires , medical elastic body. Occupies a very important position in the national economy. In recent years, the international market price of NR is high, the majority of our high consumption, labor-intensive and low-tech the NR products companies overwhelmed. In response to this critical situation, the need to strengthen the research of new technology, the application of high-tech, research and development of high performance NR composite. The NR composite processing methods are usually reinforcing agent in natural rubber Ganjiao added processing by dry mixing of the vulcanizing agent, and various compounding agents. The mixing this process both energy consumption and environmental pollution, serious harm to the health of the operating personnel. Therefore, this paper presents a traditional \This article Preparation of natural rubber latex blend / silica nanocomposites, the first γ-methacryloyloxy propyl trimethoxy silane coupling agent (MPS) modified nano-silica (SiO2), and then core-shell structure of the nano-silica particles (SiO2-MPS-PMMA) and finally with MMA modified natural rubber latex (NR-PMMA) directly co-polymethyl methacrylate (PMMA) obtained by the emulsion polymerization of graft mix, prepared natural rubber / silica nanocomposites. Different content of nano-silica composites. Using infrared spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy, dynamic mechanical thermal analyzer, thermal gravimetric analysis, and rubber tensile testing machine were modified nano silica, graft the PMMA modified the film, and the preparation of the natural rubber composites were characterized. IR spectroscopy showed: the MPS coupled modified Houna Mi-silica surface introduces a double bond, and the successful grafting of the monomer MMA in the role of initiator in the coupling of the modified silica surface of the MPS on the double bond, natural rubber latex by emulsion polymerization rubber molecular chain connected to the PMMA. TEM analysis showed that: 95% ethanol as solvent MPS coupled Modified Preparation Si02-MPS particle dispersibility than with ethanol or distilled water as a solvent to the good, grafted PMMA-modified silica particles, i.e. SiO2-MPS-PMMA, the formation of PMMA as shell Si02 nuclear core - shell structure of the particles, when MMA: SiO2 = 0.3 particle dispersion, small particle size and uniform distribution than simply using MPS modified Good, with increasing MMA content, graft increases in the molecular weight of the silica surface PMMA, leading to the intertwining of molecular chains, particle agglomeration PMMA as bridges, larger particles, MMA: SiO2 = 3 when the particle diameter exceeds 100 nm lost meaning of nanomaterials. SEM analysis showed that: the grafted PMMA modified composites NR-PMMA/SiO2-MPS-PMMA, material interface blur, good compatibility, when silica total Ganjiao mass fraction of 0.5%, the particles in the matrix The uniformly dispersed and the particle size distribution between 30 ~ 60nm, with the increase in the amount of silica, the matrix structure of silica network, when more than 3% in the amount of silica particles in different degrees of agglomeration. Dynamic mechanical thermal analysis showed: NR-PMMA/SiO2-MPS-PMMA the glass transition temperature of the composite material is higher than the glass transition temperature of the composite material of the unmodified material good low temperature resistance, and a large amount of storage modulus, good elasticity. Thermogravimetric analysis revealed that: SiO2-MPS-PMMA particles of emulsion polymerization, MMA: SiO2 = 0.3 the monomer MMA homopolymerization polymerization more, a relatively small amount of the PMMA grafted on the silica surface; with significant increase in MMA content of most of the MMA are grafted to the silica surface polymerization reaction occurs, resulting in the graft in the significant increase in molecular weight of the silica surface PMMA. Grafted PMMA modified composites NR-PMMA/SiO2-MPS-PMMA thermal stability than the unmodified composite material of improved thermal stability, and with increased silica content material while the corresponding increase. Rubber tensile test results showed that: the same content of silica, the mechanical properties of the composite the material NR-PMMA/SiO2-MPS-PMMA the mechanical properties of the composites than unmodified silica accounted Adhesive Quality Score 0.5 %, the best mechanical properties of the material, with increasing silica content, due to the formation of the network structure of the silica particles and the reunion of the reasons, the material mechanical properties have different degrees of decline.
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