The function of silane coupling agent in rubber mixing field is to combine inorganic matrix with rubber organic matrix. Silica is commonly used in the rubber mixing field to strengthen rubber. The size and amount of silica aggregates in the mixing process are important factors affecting the wear of the mixing chamber. The wear of the mixing chamber would lead to a increasing gap between the mixer chamber and the rotor, which caused the mixing efficiency reducing. It also affected the dispersion effect, then affected the mechanical and physical properties of the vulcanized rubber. In this paper, the effects of rubber compound on metal friction and wear were studied by using four silane coupling agents commonly used in rubber mixing field. The experiment was carried out at 15 C, and the attention should be paid to drying during sample preparation to avoid the deviation of the experiment caused by hydrolysis of silane coupling agent. The results showed that silanization reaction occured between silica and silane coupling agent in the mixing process.The mixing temperature was usually maintained at 145 to 155 C for 1 min in the mixer, and the silanization reaction rate was the fastest during this time.We took this rubber compound as the research object and studied the friction and wear of the rubber compound on the mixing chamber in the mixing process. The products of the silylation reaction are alcohol and water. This paper studies the corrosion and abrasion of the mixing chamber by water at high temperatures. In the mixing process, abrasive wear was the main wear form, but the corrosion wear caused by high temperature steam still occupied a large proportion.

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This study proposes that the foaming pre‐dispersion technology is combined with the gas‐phase‐assisted spray technology, and a foaming agent potassium oleate is introduced. The volume expansion power generated by the bubbles promotes the dispersion of the filler. The uniformity of foaming promotes the chemical bridging of potassium oleate between rubber and silica. Then, with a large velocity difference between the compressed air and the emulsion, the gas‐phase‐assisted spray gun refines the emulsion and breaks the filler aggregates. Next, the atomized droplets splash on the surface of the high‐temperature roller, and then deposit on it to achieve instant drying, which reduces the loss of non‐rubber components, thereby improving the preparation efficiency and comprehensive properties of masterbatch. The Payne effect of the composite prepared by the FGS technology is weaker. The tensile strength, elongation at break, and tensile product of the vulcanizate prepared by the FGS technology with 7 phr PO have increased by 9%, 5%, and 15%, respectively, and the aging coefficient is 23% higher than that of the dry mixing.

Butyl rubber (IIR) is widely used in tire inner liners and tubes, vulcanization bladders, and shock absorption materials due to its extremely low air permeability, excellent aging resistance, and good energy absorption. However, its low thermal conductivity affects its performance and the service life of the product, while it also limits its application. Therefore, the preparation of butyl rubber composites with high thermal conductivity is of great significance and practical value. This paper proposes the use of a dry ice expansion pre‐dispersion flocculation method to improve the thermal conductivity of butyl rubber composites by simultaneously doping graphene oxide (GO) and multiwalled carbon nanotube (MWCNTs) in butyl latex. The experimental results of this study show that the dry ice expansion pre‐dispersion method uses the huge volume expansion force of dry ice to break the nanofillers aggregates during sublimation, promote the dispersion of nanofillers, and achieve better modification effects. Moreover, GO and MWCNTs have good synergistic thermal conductivity, which can establish a complete three‐dimensional thermal conductivity network inside the composite. When 5 wt% of GO and 5 wt% of MWCNTs were added, GO/MWCNTs/IIR composites exhibited the highest thermal conductivity, which reached 0.423 W m−1 K−1 at 180°C.

The drying process of natural rubber latex significantly affects the structure of the raw rubber network and vulcanizate crosslinking network, resulting in various anti-aging performances. In the present study, a microwave generator was used as an efficient source of clean energy; potassium oleate was introduced as a foaming agent to increase the porosity and water loss channel of the latex system. Aiming at dehydrating and drying natural rubber latex efficiently, an aging resistant rubber composite was prepared. Meanwhile, the mechanism of the foaming agent-assisted microwave drying process on the raw rubber network and the cross-linking network was studied. The experimental results show that the prepared rubber using by this process has higher plastic retention and fluidity. Moreover, it contains more non-rubber components (e.g. protein and acetone extract) and better network structure of raw rubber and vulcanized rubber. It is found that applying this process increases the tensile product by 13.5% and the retention rate of the tensile product after aging by 15.3 times. This process is important for the development of the rubber industry in the direction of green environmental protection, energy conservation, and high efficiency.