| High-performance natural rubber has higher tensile properties and excellent resistance to ozone aging properties, in addition to better do some common uses of natural rubber, it can satisfy the need of high requirements, and has very broad application prospects.However,in the actual production, it is found that the high-performance natural rubber will also have the phenomenon of storage hardening as the ordinary rubber in the process of transportation, storage, etc. The occurrence of this phenomenon will bring about the heterogeneity of the apparent viscosity of the gum, which will have a serious impact on the subsequent production and processing, meanwhile, will lead to the loss of the high performance of rubber. This topic will carry out the relevant research in order to solve these problems mentioned above.Using a new type of constant adhesive 2-mercaptobenzothiazole (MBT) for high-performance natural rubber with constant viscosity properties preparation, to study the effects of different amount of MBT on the viscosity of rubber. In addition, by means of test and analysis, the phenomenon of storage hardening and the constant viscosity of MBT were studied from the aspect of theory. The paper also studied the effect of MBT added on high-performance and high-performance maintaining in the storage process, mainly on ozone aging properties of rubber. Moreover, the mechanism of ozone aging and the effect of MBT on ozone aging resistance were studied.The results show that a small amount of MBT can not have a good effect on high performance natural rubber. When the amount of MBT is above 0.15%, mooney viscosity and plasticity of the accelerated storage sample changes a little, storage hardening value?Mv??P are below 4, rubber reached a good constant viscosity effect. The results of the plastic retention rate also showed the constant viscosity effect of MBT.. The study of molecular weight, gel content and infrared found that rubber crosslinking in the storage hardening process due to the exist of internal aldehyde, by adding MBT early reaction with aldehyde group can inhibit the occurrence of subsequent storage harden, which confirms the storage mechanism of aldehyde. The study of the effect of MBT on high performance shows that the effect of MBT addition on high performance is basically beneficial. In the aspect of tensile properties, the adverse effects of MBT on tensile properties can be ignored,The tensile properties after accelerated storage can be maintained to a large extent, which can effectively solve the effect of storage hardening on the tensile properties of the rubber in the aspect of ozone aging resistance. The addition of MBT in a certain amount of range has a promoting effect on ozone aging resistance, when the addition of 0.15% to achieve the best performance of ozone aging. After accelerated storage, the addition of MBT has a certain effect on the maintenance of ozone aging resistance of samples. Although the effect is not good, but in case of 0.15%?0.20% MBT addtion, the final performance of ozone aging resistance was better than that of A group without adding constant viscosity after storage. The results of in situ FTIR show that the ozone reaction occurred during the aging of ozone and the further explanation of the aging mechanism. The results also speculated the reason that the effect of MBT on the aging resistance of rubber.In summary, the study found that adding 0.15% MBT dosage can be effectively prepare good constant viscosity effect and excellent ozone aging resistance high viscosity natural rubber, which provides an important theoretical guidance and reference value for the actual production. |
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