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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.

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This paper prepared potassium oleate/silica/natural rubber composites by atomization spray drying technology. This study compared the effects of the environmental protection accelerator potassium oleate and amine accelerator 1,3-diphenylguanidine on the Payne effect, silane reaction index, vulcanization performance, mechanical properties, static and dynamic mechanical properties, and aging properties of silica/natural rubber. The results show that potassium oleate can promote the silane reaction and increase the silane reaction's efficiency. When potassium oleate formed the silica coating, the carboxyl group of potassium oleate and the hydroxyl group of silica were bonded to form a covalent bond, which reduced the polarity of silica and promoted the dispersion effect of silica in the rubber matrix and enhanced the compatibility with rubber. Compared with the original formulation, after adding 3 phr of potassium oleate, the fracture elongation of vulcanized rubber was increased by 17.2%, tensile product increased by 57.3% and rolling resistance decreased by 54.6%. After adding 3 phr of 1,3-diphenylguanidine, the fracture elongation of vulcanized rubber was increased by 1.1%, tensile product increased by 51.1% and rolling resistance decreased by 48.6%. In contrast, the anti-aging performance of the rubber composites with potassium oleate was better than that of 1,3-diphenylguanidine. This study opens up a new way to apply a new green rubber accelerator and prepare high-performance rubber composites.

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