The structure of the compound is due to the fact that the compound made of hydrophilic silica and raw rubber slowly hardens and reduces its plasticity during storage, and gradually loses the process performance of remanufacturing and molding processing. The main reason for the structure is that the silicon hydroxyl on the surface of silica and the silicon oxygen bond in the raw rubber molecule or the terminal hydroxyl group in the raw rubber molecule form hydrogen bond, and even chemical combination, The solid structure of linear polysiloxane transformed into pseudo cross linked semi elastomers reduces the solubility of the rubber and increases the gel content.

Generally speaking, the plasticity of the compound can be restored through remanufacturing, and the length of remanufacturing time depends on the structural severity of the compound. In order to reduce the hydrogen bond bonding of the rubber and reduce the structural degree of the rubber, structural control agents such as hydroxyl silicone oil, diphenyl silicone glycol or alkoxysilane can be added. At the same time, an appropriate amount of dimethyl silicone oil can be added to adjust the flow performance of the rubber. Too much hydroxyl silicone oil will lead to sticky feel and slow vulcanization speed, It is necessary to find a suitable balance point. Each type of rubber can be controlled within an appropriate plastic value range. Low or high plastic value will affect the later product processing. If the plastic value is low, there will be roll sticking in the processing process, and mucous membrane or rotten scar may appear in the production process of the product; If the plasticity value is too high, it will cause rubber structure and poor rubber fluidity, and the products may lack rubber or flow marks.

We can also improve the process of rubber compound production. At present, the production of rubber compound adopts one-step method, so the combination of white carbon black and raw rubber is not very complete. Although no obvious abnormalities are found on the surface, sometimes small white spots are observed in the rubber, which can be produced by the process of mixing (normal temperature) - Health Preservation - internal mixing, Improve the combination of silica and raw rubber to improve the structure of rubber.

In addition, in the selection of raw rubber, the molecular weight of raw rubber is too high or too low, and there are terminal hydroxyl groups or other impurities in the raw rubber molecules, which will not increase the molecular weight of raw rubber, which will affect the processing performance and vulcanization performance of the compound. Therefore, in terms of raw material control, it is better not to have a peak in front of D3, and the addition amount of head sealing agent with the same molecular weight should be as consistent as possible, Count the conversion rate of each batch of raw rubber in the production process to control the quality of raw rubber.