Organic Montmorillonite Rubber Wear Mechanism And Application Of Research

Several kinds of nanocomposite materials having excellent performance were prepared by traditional mechanical blending with different species of organic montmorillonite (OMMT) and rubbers, according to experimental results, the macro morphology of worn surface and microscopic structure of nano slice layer analysis as research method, the wear-resistant mechanism of OMMT in rubber as research purpose, and it laid the foundation for further application of organic montmorillonite in industrial production. The main contents are summarized as follows:1. Three kinds of nanocomposites (NR/OMMT, BR/OMMT and EPDM/OMMT) were prepared by mechanical blending with five different kinds of homemade OMMT by our own laboratory, and the mechanical properties, abrasion resisitence, cure characteristics and the surface morphology after wear of composites were comparative analyzed, investigated the relationship of the species of OMMT and rubbers, the best overall performance and suited to non-polar rubber of 2# OMMT was selected. When the loadings of OMMT were only 3.0 parts per hundreds of rubber (phr), the mechanical properties of all composites were improved greatly, and the Akron wear volumes were reduced by more than 55%, the typical ridge-like wear patterns emerged on the wear surface, and patterns become more fine and subtle.2. The completely exfoliated OMMT/NR nanocomposites with uniform dispersion in NR matrix were confirmed by TEM. The impact of 2# OMMT contents were mianly investigated on the composites properties, and compared with the performance of HAF carbon black N330. The results showed mechanical properties and thermal stability of NR/OMMT nanocomposites increased significantly with the addition of OMMT content and much higher than that of the pure NR, in comparison with the identical HAF carbon black N330, the reinforcement effect of OMMT was better. In addition, the Akron wear volume of composite with 3.0 phr OMMT was equivalent to that of 21.0 phr HAF carbon black N330. It demonstrated that the improvement of OMMT on wear resistance of natural rubber was more significant, it mainly related to good barrier property, lubricity and compatibility of the dispersed OMMT layers, reduced the mobility of the molecular chain segment and the ability to crack propagation.3. The effects of different content of 2# OMMT on the properties of NR/SBR and NR/BR blends were studied, the results showed OMMT acted as similar vulcanization accelerator, and the efficiency of vulcanization and production was improved. The tensile strength, tear strength, abrasion resistance and thermal stability of the two blends were improved greatly, in particular to the improvement of abrasion resistance was the most significant. When the OMMT contents were only 3.0 phr, the Akron wear volumes were reduced by 65.9% and 68.2%, respectively. It also reflected the advantage of OMMT which has excellent reinforcement effect with low content. Moreover, SEM photographs of worn surface demonstrated that OMMT layers which dispersed in the interface of the two rubbers played a role in compatibilization and reinforcement, the worn surface was more smoothly and no defects appeared.4. Combined with the wear-resisting mechanism of OMMT, the applications of OMMT in tire tread, tire sidewall, and wear-resistence tube industrial formulations were investigated, OMMT layers and carbon black particles fully exerted their synergistic reinforcement effect, and evidently improved the mechanical properties, abrasion resistance and anti-aging properties of the composites. Moreover, the best amount of OMMT was 3.0 to 6.0 phr, and could significantly improve the comprehensive performance of the industrial formulations. The outstanding overall performance of rubber industrial formulations with OMMT reinforcement indicated a good application prospect of OMMT in tire and tube industry.In conclusion, experimental results showed that the special lamellar structure of organic montmorillonite, the compatibility of OMMT layers with rubber matrix and the dispersion morphology of layers (uniformity, size, orientation and other factors) detemined the merits of the anti-wear properties of nanocomposites, reflected the nature of performance determined by structure, and it had high practical guiding significance and application value.