Influence of Basalt Fibres on the Physical-Mechanical, Performance and Dynamic Properties of Rubber for Rail Pads

The effect of basalt fibres on the rheometric, physical-mechanical, performance and dynamic (vibration absorbing) properties of rubber used for rail fastenings is investigated. The rubber mixture based on butadiene-methylstyrene (SKMS-30ARK), isoprene (SKI-3) and butadiene-nitrile (SKN 2655) caoutchoucs contained also vulcanising agents (sulphur, N,N '-dithiodimorpholine, tetramethylthiuram disulphide), vulcanisation accelerator (N-cyclohexyl-2-benzothiazole sulphenamide), vulcanisation activators (zinc oxide, stearic acid), softeners (industrial oil I-12A, rosin), antioxidants (N-phenyl-N '-isopropyl-para-phenylenediamine, wax ZV-P, acetonanil N), fillers (kaolin, carbon black of N 220 and P 514 grades, silicon dioxide Zeosil 1165 MP) and other ingredients. The strength properties and hardness of the vulcanisates are observed to increase with an increase in the content of basalt fibres in the rubber mixture. Basalt fibres reduce changes in the elastic-strength parameters of vulcanisates after daily thermal aging in air and under the action of the standard petroleum fluid SZhR-1. The improved dynamic (vibration damping) properties are exhibited by vulcanised rubber containing 12.0 phr basalt fibres.