Rubber Chem Encyclopedia

Types and functions of softeners commonly used in the production of nitrile rubber products

Create Date:2019-11-22 08:56:12Click volume:154
Types and functions of softeners commonly used in the production of nitrile rubber products

The rubber softener can soften the rubber compound in the production process of the nitrile rubber product, improve the plasticity and adhesion, and promote the uniform dispersion of the compounding agent in the rubber compound. It is an indispensable compounding agent in the production of NBR products. In actual production, the processing performance of different grades of nitrile rubber and nitrile reclaimed rubber processed from different raw materials is different, and it is necessary to match different kinds of softeners. So what are the commonly used softeners in the production of nitrile rubber/recycled rubber products? What is the role?

1. Coumarone resin

Gumalon has good compatibility in nitrile rubber and is not easily extracted in solvent. The low softening point of coumarone can improve the mixing process of nitrile rubber or reclaimed rubber. Coumarone resin during processing It can also dissolve a certain amount of sulfur to achieve the purpose of reducing the probability of sulfur injection and scorch; Gumalon promotes the dispersion of sulfur, and improves the tensile strength and hardness of nitrile rubber and reclaimed rubber vulcanizate.

The dosage of coumarone resin in the processing of nitrile rubber products is generally controlled at about 10 parts, and the liquid coumarone has a certain viscosity-increasing effect.

2. Coal coke resin

Coal char resin is very common in the production formula of nitrile rubber products. As a by-product of coal coking, coal coke resin has good compatibility with nitrile rubber, which plays a role of softening and thickening; it should be noted that coal char The asphalt contained in the resin component can also reduce the thermal aging resistance and flex crack resistance of the nitrile rubber/recycled rubber. Therefore, the rubber product manufacturer needs to properly control the amount of the coal coke resin in the nitrile rubber formulation.

3. Liquid nitrile rubber

The liquid nitrile rubber is a nitrile rubber in a viscous liquid state at normal temperature, and can be used as a softener and a plasticizer in the production of rubber products; the liquid nitrile has good compatibility with the nitrile rubber or the nitrile reclaimed rubber. It has the characteristics of high temperature non-volatility and large amount of use without seepage. Therefore, the migration problem of the nitrile rubber product or the nitrile reclaimed rubber product using the liquid butyronitrile as the softening agent does not substantially occur during production and use.

As a renewable resource for the recovery and reuse of nitrile rubber or waste nitrile rubber products, nitrile reclaimed rubber has better plasticity and fluidity. Combined with nitrile rubber, it can improve the performance of nitrile rubber processing and reduce it to a certain extent. Raw material costs, reducing production energy consumption. When using nitrile rubber/recycled rubber to produce oil-resistant and wear-resistant rubber products, the amount of softener in the formulation should be adjusted in time according to the change of the amount of reclaimed rubber.