Evaluating the effect of environmental conditions on high compressive strain rates in unfilled and filled neoprene rubbers

J Elastomers Plast. 2023 Dec;55(8):1199-1212. doi: 10.1177/00952443231197727. Epub 2023 Aug 22.

Abstract

Elastomers are known for their strain-rate-dependent properties not only to quasistatic but also to high strain rate deformations, where mechanical behavior is significantly affected by inertia. Concurrently, environmental changes, such as temperature and humidity variations, can impact their stress response to deformation. This study investigates the effects of material layers within neoprene samples on mitigating these environmental changes. While the presence of an intermediate layer proves effective against temperature and humidity influence, it fails to block the impact of increasing high strain rates. Moreover, the different humidity levels at room and elevated temperatures do not significantly alter the mechanical behavior of filled neoprene samples compared to pure neoprene. Notably, in unfilled neoprene, an increase in humidity levels, other than an absolutely dry environment, leads to a notable stress level rise at room temperature, while under elevated temperature conditions, there is a significant stress decrease with increasing humidity. However, neoprene filled with polyester/cotton or nylon displays resilience to diminishing mechanical behavior under various temperature and humidity regulations, indicating that the material layer within these samples effectively "protects" the rubbers from potential stress lapses observed in unfilled neoprene. While a high strain rate compression affects the behavior of the filled variants significantly, increasing humidity and temperature have minimal impact on their stress levels. These findings offer valuable insights into the dynamic responses of elastomers to environmental changes, highlighting the advantages of using filled rubbers in diverse applications.

Keywords: Filled neoprene rubber; Kolsky bar; high strain rate; humidity effect; temperature effect.