Effect of softener on rubber hardness

The main function of softener is to make rubber molecules swell and soften, reduce intermolecular friction, thus increasing plasticity, or wet the compound of raw rubber, so that the compound is easy to evenly disperse in the raw rubber. Softener can make rubber pollution and plasticity, so it can reduce plasticizing time, reduce energy consumption, so that the rubber is easy to calendering and pressing out.

Effect of softener on rubber hardness

Some softeners, not only play a far role, and can play other roles, such as stearic acid can activate the promoter, pine tar can increase adhesion, and have the effect of aging, phthalate dibutyl alcohol can increase the cold resistance of rubber; Rosin and oleic acid can promote aging. When the amount of paraffin and dense wax is greater than 1%, it will be compounded on the rubber surface to form a layer of film. Although it still has aging resistance, it will reduce adhesion.

The ideal rubber softener must be stable and volatile, easy to mix with raw rubber, and does not promote the aging of products, nor reduce the strength of products and other properties.

Softener has different effects on rubber hardness, which can be divided into the following three kinds:

1 with the increase in the amount of rubber hardness, such as vaseline, vegetable oil, vulcanized oil and so on.

2. Rubber hardness decreases very little, such as fatty acids and salts.

3. Do not reduce the hardness, but increase the hardness with carbon black, such as mineral yellow rubber, pine tar, etc..

There are many kinds of rubber softener, such as mineral R rubber, paraffin, stearic acid, coal tar and synthetic products (such as polydiene, diethyl phthalate vinegar).