EPDM–chlorobutyl rubber blends in γ‐radiation and hydrocarbon environment: Mechanical, transport, and ageing behavior

Abstract

In nuclear applications, ethylene propylene diene monomer (EPDM) rubber is the material of choice as gaskets and Orings due to its radiations resistance. In nuclear fuel reprocessing, in addition to radiation, the elastomeric components have to withstand paraffinic hydrocarbons as well. But, EPDM has poor resistance to hydrocarbons. To enhance the durability of EPDM in such environments, EPDM-chlorobutyl rubber (CIIR) blends of varying compositions were developed and characterized for mechanical, thermal, dielectric, and solvent sorption behavior. Spectroscopic and morphological analysis was used to evaluate the compatibility of blends. Due to synergistic effect, the optimal composition of blends with superior mechanical properties and solvent resistance were found to be 60% to 80% EPDM and 20% to 40% CIIR. The optimized blends were irradiated with gamma rays at cumulative doses up to 2 MGy. Based on spectroscopic, morphological, mechanical, thermogravimetric, and sorption properties, blend containing 80% EPDM was found to have superior retention of properties after irradiation.

Effects of Electron Beam Irradiation on the Mechanical, Thermal, and Surface Properties of Some EPDM/Butyl Rubber Composites

“…In addition, due to its nonpolar character, EPDM has superior electric resistivity, particular retention properties (even after ageing), and high resistance against polar solvents such as water, acids, alkalies, ketones, or alcohols [3,4]. Due to the special electrical properties, ageing resistance, and elevated temperature resistance, EPDM elastomers can be utilized as electrical insulating materials, automotive profiles, electrical cables, roofing materials, window gaskets, or in different nuclear applications [1,5,6].…”

“…Due to the absence of double bonds in the backbone, butyl rubber is stable in diluted solutions of acids or alkalies, as well as to prolonged heat exposure. Also, butyl rubber, due to its excellent properties, has found applications as materials utilized in high-pressure conditions and to damp shocks and vibrations [5,7]. The specific working range for products based on butyl rubber is from −50 to 120 °C.…”

“…The chlorination and bromination process of butyl rubber leads to the halogenation of isoprene units in butyl rubber. Chlorobutyl rubbers present a low gas and moisture permeability, good resistance to weathering and hydrocarbon solvents, and high thermal stability [5,8]. EPDM has better mechanical properties than the butyl/halogenated butyl rubbers.…”

Gamma radiation induced compressive response of silicon rubber foam: Experiments and modeling

“…For the purpose of modification, rubber foam materials are usually exposed to high-energy radiation such as Gamma radiation [4]. Ashok et al (2017) noted that the influence of the Gamma radiation affects polymers in two ways. One is chain scission which results in reduced tensile strength and elongation at break.…”

“…One is chain scission which results in reduced tensile strength and elongation at break. The other is crosslinking which increases tensile strength but reduces the elongation at break [5]. Many researchers conclude that the Gamma radiation could strongly affect the mechanical properties of rubber materials, which accordingly affects the stability and reliability of the structures.…”