Zinc oxide special for natural rubber and preparation method of zinc oxide

Abstract

The invention discloses zinc oxide special for natural rubber and a preparation method of the zinc oxide. The zinc oxide special for the natural rubber comprises, by weight, 50-70 parts of zinc oxide, 10-20 parts of zinc stearate, 15-25 parts of zinc p-toluate and 2-5 parts of dispersant. The preparation method of the zinc oxide comprises the following steps of 1, adding the dispersant to a zinc sulfate solution, and conducting stirring so that the dispersant can be uniformly dispersed in the solution; 2, adding p-toluylic acid and stearic acid to a sodium hydroxide solution, conducting stirring while the mixture is heated to 60 DEG C, and continuing with heat preservation and stirring till a reaction is conducted completely; 3, under the condition that stirring is conducted ceaselessly, adjusting the pH value of a mixed solution which is obtained in step 1 and step 2 after the reaction is conducted for a while with a sodium hydroxide solution, continuing stirring till the reaction is ended, and then conducting centrifugal separation; 4, drying filter cakes obtained after separation, so that the zinc oxide special for the natural rubber is obtained. The zinc oxide has the vulcanization activating function and can improve anti-vulcanization reversion performance of the natural rubber, and dispersibility of the zinc oxide in a rubber material is good.

Description

technical field [0001] The invention belongs to the field of fine chemicals and relates to a highly dispersed zinc oxide and a preparation method thereof. Background technique [0002] As a general-purpose rubber, natural rubber (NR) has good elasticity and mechanical properties, and has been widely used in various sectors of the national economy. However, NR will undergo vulcanization reversion to different degrees in the sulfur vulcanization system, which greatly limits the application of NR, especially for thick products such as engineering tires. Reversion refers to the decrease of crosslink density caused by the thermal degradation of polysulfide bonds, the change of crosslink type distribution, and the modification of the main chain. Vulcanization reversion will lead to a decrease in the physical properties of the vulcanized rubber, a decrease in the elastic modulus, and an increase in the viscous modulus, which will seriously damage the dynamic properties of the rubb...

AI Technical Summary

Problems solved by technology

However, the NR system using sulfur vulcanization will have the phenomenon of reversion

In addition, zinc oxide is an inorganic substance, and the difference in solubility parameters with rubber polymers is doomed to poor compatibility between the two, and the dispersion of zinc oxide in the rubber field also needs to be solved urgently

[0005] At present, there is a lack of a special zinc oxide for natural rubber, which has good dispersion in natural rubber, and can improve the anti-reversion problem of the rubber compound, and thus improve the physical and mechanical properties of rubber products (especially thick products)

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