Frost spray is one of the common problems in the production process of rubber products, ranging from affecting the appearance of rubber products to affecting the performance and shortening the service life of the products. In the production process of colored natural rubber outsoles, the frosting is mostly caused by the excessive amount of the compounding agent. Therefore, the reasonable use of the compounding agent is important to prevent the frosting of the rubber soles. Xiaobian will share with you today how to adjust the formula The type and amount of agent to avoid frost.
1. Reference formula of colored natural rubber molded outsole
40 parts of natural rubber, 50 parts of styrene butadiene rubber, 10 parts of butadiene rubber, 5 parts of zinc oxide, 1.5 parts of stearic acid, 0.2 parts of channel carbon black, 35 parts of white carbon black, 28 parts of clay, 10 parts of softener, Antioxidant 1.3 parts, terpene resin 2 parts, accelerator DPG 0.4 parts, accelerator CZ 0.5 parts, accelerator DM 1 part, accelerator M 1.2 parts, sulfur 2.3 parts, pigment, appropriate amount.
2. Form and reason of rubber products frost
The so-called frost spray is the phenomenon that the liquid or solid softener in the rubber product migrates from the rubber to the rubber surface, which can be divided into three types: powder spray (vulcanizing agent, accelerator, active agent, anti-aging agent, filler 2LLYY71, etc. Powdery compounding agent precipitates the rubber surface), wax spray (paraffin wax and other waxy material precipitates the rubber surface), oil spray (softener, tackifier, lubricant, plasticizer and other liquid compounding agent precipitated surface).
3. How to avoid colored natural rubber outsole frosting
One reason is that the compounding agent in the colored rubber outsole will precipitate the surface of the object. One possibility is that the compounding agent is used in an excessive amount. The other is because the compounding agent itself is prone to discoloration and migration. Caused by compatibility.
(1) Controlling the dosage of compounding agents: To avoid frosting of colored outsoles, first of all, you need to understand the solubility of various compounding agents in rubber, reasonably control the dosage of compounding agents, or use two or more compounding agents together to avoid compounding agents Excessive dosage will precipitate the surface of the object; for example, the anti-aging system in the above formula can use the anti-aging agent MB and the anti-aging agent SP-C together.
(2) Avoid the use of easy-to-migrate compounding agents: to prevent color natural rubber outsole frosting, it is necessary to avoid the use of rubber additives that are prone to discoloration and migration such as dioctyl sebacate, trioctyl phosphate, etc. They are very important in rubber products Migration is easy. Colorant is an indispensable compounding agent in the production process of colored rubber outsole. Rubber product manufacturers must choose colorants with excellent light resistance and heat resistance, and avoid the use of colorants such as Hansa yellow and toluidine red, which are prone to migration.
In general, inorganic colorants have good heat and light resistance, strong hiding power, excellent solvent resistance, chemical resistance, and migration resistance, but poor coloring power. Compared with inorganic colorants, organic colorants have There are many varieties, good dispersion, bright color, strong coloring power, good transparency, low dosage and other advantages, but the heat resistance, solvent resistance, chemical resistance, migration resistance are poor.
To prevent the frosting of colored rubber outsoles, rubber product manufacturers must consider from various aspects, cut off the possibility of frosting as much as possible, and effectively avoid the problem of discoloration and migration of colored natural rubber outsoles.