SPECIAL FEATURES OF RELAXATION PROPERTIES OF ELASTOMER COMPOSITIONS WITH HIGHLY DISPERSED CARBON ADDITIVES

The infl uence of three diff erent nanostructured carbon materials: nonfunctionalized and functionalized with oxygen- and amino-containing groups on the relaxation properties of elastomer compositions was studied. Rubber compounds based on natural rubber and nitrile butadiene rubber were used as elastomeric matrices. Determination of the relaxation properties of rubber compounds and rubbers based on them was carried out on the basis of calculations of the stress relaxation coeffi cient and the conditionally equilibrium modulus. It has been established that functionalized carbon nanomaterials exert the most signifi cant eff ect on the acceleration of relaxation processes in rubber compounds based on polar rubber due to a possible decrease in the intermolecular interaction of its polar groups. In compositions based on natural rubber, the introduction of functionalized nanomaterials increases the rate of relaxation processes only in compositions with semi-reinforcing carbon black, which is due to the lower interactions of elastomer macromolecules with chain structures of the fi ller. It has been found that in compositions based on nitrile butadiene rubber, the use of carbon nanomaterials, in comparison with rubber without nanoadditives, leads to an increase in the conditionally equilibrium modulus in vulcanizates with both semi-reinforcing and high-reinforcing carbon black at a dosage of 50.0 wt.pts. Rubbers based on nonpolar rubber containing carbon nanomaterials are characterized by increased values of conditionally equilibrium modulus only in the case of compositions with semireinforcing carbon black at a dosage of 50.0 wt.pts.
   
Author:  Zh. S. Shashok, N. R. Prokopchuk, E. P. Uss, S. A. Zhdanok, A. V. Krauklis
Keywords:  rubber, vulcanized rubber, carbon nanomaterials, relaxation coeffi cient, conditionally equilibrium modulus