Modification of nitrile rubber 2980 with liquid nitrile rubber YN 25

Abstract

Nitrile rubber （NBR） 2980 M was prepared by mechanical blending of liquid nitrile rubber （YN 25） into NBR 2980. The effect of YN 25 addition ratio on the Mooney viscosity, hardness, vulcanization characteristics of NBR 2980 M compound, and tensile properties of NBR 2980 M vulcanizate were studied. The results showed that with the increase of YN 25, Mooney viscosity, modulus at 300% at 50 min, tensile strength, maximum and minimum torque of NBR 2980 M all decreased li-nearly, while the elongation at break and three torque differences vulcanization times of 25 min, 50 min, and 90 min all increased linearly. However, the change in hardness of the compound was not significant. For increase in mass fraction of YN 25 in NBR 2980 M by 1%, Mooney viscosity of the compound decreases by 0.78, and the modulus at 300%, tensile strength, maximum and minimum torque of the vulcanizate decrease by 0.25 MPa, 0.17 MPa, 0.12 dN·m, and 0.02 dN·m, respectively. The elongation at break and three vulcanization times of 25 min, 50 min, and 90 min increase by 4.1%, 0.05 min, 0.08 min, and 0.18 min, respectively.

Keywords

• nitrile rubber， liquid nitrile rubber， mechanical blending， modification， mooney viscosity， vulcanization characteristics， tensile property，