Impact of the Composition of Rubbers Filled with Carboxymethyl Cellulose on Their Properties

The impact of the amount of water-swellable filler sodium carboxymethylcellulose of Polycell-9B grade (particle size 1.0–2.0 mm) on the complex of physical and mechanical properties of limited swelling rubbers based on nitrile butadiene rubber of BNKS-28 AMN grade with a sulfur vulcanizing system was studied. The composition with a ratio of the rubber compound without swelling filler to sodium carboxymethylcellulose was varied in the range (65–35) : (35–65) (wt. parts). It was established that the introduction of a swelling filler into the rubber compound has virtually no effect on the time to achieve the optimal vulcanization time and is 10 min at a temperature of 170°C. It was shown that the introduction of sodium carboxymethylcellulose leads to a decrease in the deformation-strength properties of rubbers, however, the strength characteristics of modified rubbers allow the use of the developed rubber compositions for the manufacture of sealing elements of water-swellable packers. It was revealed that with an increase in the proportion of the swelling filler, sodium carboxymethylcellulose, the vulcanizate exhibits a higher sorption capacity in aqueous media with different pH.