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The influences of bentonite and different silane coupling agents (SCA) on the viscoelastic properties of nitrile butadiene rubber were studied in this work. The silane coupling agents compatibilized bentonite/nitrile butadiene rubber nanocomposites were fabricated by a novel green method. The viscoelastic behaviors of the nanocomposites and their vulcanizates were explored using a rubber processing analyzer (RPA) in the modes of strain sweep and frequency sweep. Storage modulus (G′) and elastic torque (S′) of nitrile butadiene rubber increased significantly with the incorporation of bentonite. In the SCA applied in this work, mercaptopropyltrimethoxysilane (MPTMS) contributed to high storage modulus (G′) of the nanocomposites because of thorough exfoliation of bentonite and short sulfur bonds formed during curing process. Meanwhile, multi-sulfur bonds in bis-[3-(triethoxysilyl)propyl] tetrasulfide (TESPT) and reversible interactions from [3-(2-aminoethylamino)propyl] trimethoxysilane (AEAPTMS) resulted in lower storage modulus of the cured nanocomposites.

In the present work, maleic anhydride (MA) and biphenyl peroxide (BPO) were used in the preparation of kaolin (K)/poly(e-caprolactone) (PCL)/poly(lactic acid) (PLA) composites with melt compounding method. Composition and structure of the composites were characterized by Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and field emission-scanning electron microscopy (FE-SEM). Mechanical properties and thermal behaviors of the composites were further investigated. Kaolin selectively located in poly(e-caprolactone) domains and at the phase boundaries, which improved the mechanical properties of the composites due to their rigid structure and high modulus. Influences of maleic anhydride on dispersion state of kaolin and two-phase structure of the composites were explored and discussed. Maleic anhydride enhanced the interactions among kaolin, poly(lactic acid) and poly(e-caprolactone). Meanwhile, it improved the dispersion state of kaolin in the composites. In the presence of both kaolin and maleic anhydride, tensile strength at room temperature and storage modulus at 40 °C were enhanced to 41.2 MPa and 3.9 GPa, respectively.