| Preparing rubber composites is an effective method to improve rubber properties and extend their application. A novel organic-inorganic composite was prepared by curing hydrogenated carboxylated nitrile rubber (HXNBR) with epoxycyclohexyl polyhedral oligomeric silsesquioxanes (epoxycyclohexyl POSS). With the increasing POSS content, the dielectric property as well as the hydrophobic property of the composites was improved; the glass transition temperature, degree of crosslink, and storage modulous of the composites were increased; and tanδdecreased; however, the mechanical property was not well improved.The curing kinetics of epoxycyclohexyl POSS/HXNBR was investigated by the Differential Scanning Calorimetry (DSC). Multiple-heating-rate models (Kissinger, Flynn-Wall-Ozawa and Crane methods) and the single-heating-rate model were employed. The apparent activation energy (Ea) obtained showed dependence on the POSS content and heating rate (β). The overall reaction order n was practically constant and close to 1. The iso-conversion Flynn-Wall-Ozawa method was also performed and fit well in the study. With the single-heating-rate model, the average Ea for the compound with a certain POSS content, 66.90-104.13 kJ/mol, was greater than that obtained with Kissinger and Flynn-Wall-Ozawa methods. Furthermore, the calculated reaction rate (dα/dt) vs. temperature curves fit with the experimental data. The reinforcement of zinc oxide (ZnO) for HXNBR is comparative studied. HXNBR cured with ZnO forms an ionic elastomer, due to formation of ionic clusters. The tensile strength of the ionic elastomer of HXNBR/ZnO is higher than 55 MPa when the loading of ZnO reaching 4 phr, and it is interesting to see the stress-hardening phenomenon for it, compared with the common stress-softening phenomenon for vulcanizates. The stress-hardening phenomenon may be attributed to formation of crystalline phase or alignment of chains in the ionic elastomer under the external tensile force, according to the X-ray diffraction analysis. And according to the SEM analysis, the zinc oxide particles are well dispersed in HXNBR.A functional composite with unique photoluminescence property, excellent mechanical property and fine thermal stabilities were prepared through reactive blending of HXNBR and zinc carbonate basic (m-3Zn(OH)2·2ZnCO3). The m-3Zn(OH)2·2ZnCO3 was obtained by sedimentation modification in superheated water using zinc nitrate and ammonium carbonate as raw materials. Photoluminescence spectra of the composites showed a characteristic emission band at 353 nm, which was attributed to formation of the interface kernel/coating of -(C=O)-O-[ZnO]. The zinc carbonate basic is well dispersed in HXNBR, and the ionic crosslink affords the composites with good mechanical properties. The tensile strength of the composites is higher than 50 MPa with 8 phr m-3Zn(OH)2·2ZnCO3. The results of TEM analysis show that the m-3Zn(OH)2·2ZnCO3 particles exhibit a large porosity of the mesopore size, and the particle pore size is obviously smaller with increasing modification time in superheated water, indicating a larger porosity and thus higher surface area. The large porosity could contribute to more interface kernel/coating of -(C=O)-O-[ZnO], which results in higher luminescence intensity and tensile strength. According to the thermogravimetric analysis (TGA), the HXNBR/m-3Zn(OH)2·2ZnCO3 composites decompose at around 430°C, a lot higher than the HXNBR decomposition temperature at around 410°C, and m-3Zn(OH)2·2ZnCO3 begins to decompose at around 270°C, a lot higher than the decomposition temperature of the zinc carbonate basic without sedimentation modification in superheated water at around 210°C.
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