Experimental and Numerical Evaluations of Localized Stress Relaxation for Vulcanized Rubber

Abstract

Vulcanized rubbers are commonly used to provide the energy absorption under compressive deformation from other engineering components. However, if a constant compressive deformation is maintained on rubber, the load response is not constant but decreases with time; i.e., the stress relaxation. A decrease in force response with time of rubber can be experimentally evaluated by the stress relaxation test. In the present work, the localized stress of vulcanized rubber during a compressive stress relaxation test (i.e., ASTM D6147) was evaluated. Hyperelastic behavior was assumed during rapid application of strain, while the viscoelastic behavior was assumed during stress relaxation. Hyperelastic and viscoelastic parameters were experimentally evaluated using a standard specimen. Finite element analysis (FEA) models were applied for the predictions of stress relaxations of rubbers with various geometries and applied strains. FEA results were in good agreement with results of the stress relaxation tests. Localized stresses in rubber during rapid application of compressive strain and stress relaxation were successfully evaluated. The findings can give the localized phenomena of vulcanized rubber during a stress relaxation test, which can be used as a guideline for the design, usage, and improvement of rubber and viscoelastic polymeric components.

Compression Relaxation of Multi-Structure Polymer Composites in Penetrating Liquid Medium

“…The parameter χ can be calculated using the Flory–Rener equation [ 16 , 20 , 23 ]: where Z is a dimensionless parameter equal to the ratio of the molar volume of the subchains of the polymer network to the molar volume of the solvent [ 22 ]: where R is the universal gas constant, E is the elasticity modulus of the swollen polymer and ϕ is the local volume fraction of the polymer in the polymer–solvent system.…”

“…Understanding the relationship between the sorption processes occurring in composites in contact with liquids, stress [ 16 ] and ORFB deformation kinetics as well as the reason for the loss of the elastic properties of polymer composites is important for various applications [ 16 , 17 , 18 ] and for the uninterrupted operation of offset printing machines [ 18 ].…”

Electrical conductivity of modified fabrics with carbon coating

“…При циклических деформациях растяжения и сокращения датчиков проявляется эффект Патрикеева-Малинза, который заключается в обратимости деформации и существенном различии первого и последующих циклов. Такое явление наблюдается не только в резистивных тензодатчиках, но и в механике композитов органической и неорганической природы [19]. В настоящее время физическая природа эффекта Патрикеева-Маллинза является объектом теоретических и экспериментальных исследований в коллективах ученых разных стран [20].…”

Thermodynamics of solvent sorption by layers of carbon-chain polymers in damping rubber blankets

“…Crosslinked carbon-chain thermoplastic elastomers are extensively used for rubber covering of power cylindrical and plane components in units exposed to multiple compression and shear deformation in manufacturing household appliances, printing, mechanical engineering and in transport facilities [1]. The chemical resistance of carbon-chain polymers to aqueous solutions of acids and alkalis enables the manufacture of hoses, rubber hoses and pipes, and protective coatings for metal products that are repeatedly exposed to various liquid media.…”