Optimization of hybrid oil/water‐swelling ethylene/propylene/diene monomer compounds

Abstract

Hybrid swell packers are rubber products capable of swelling in (saline) water and hydrocarbon oils, by exploiting the hydrocarbon diffusion properties of an nonpolar elastomer with the osmotic swelling of a water absorbent (WA). In this study, a variety of modified natural and synthetic WAs and mixtures thereof have been screened in a rubber compound with respect to swelling in decalin, demineralized, and saline water, respectively. We aimed at achieving high and fast swelling in all used media. Mixing of the various WAs in an ethylene/propylene/diene monomer (EPDM)/carbon black masterbatch at an addition level of 75 phr did not pose any problems, although it was found that the WAs did affect the sulfur vulcanization. Decalin swelling of the vulcanizates is very fast, reaching high equilibrium swelling within 1.5 days. Swelling in demineralized or saline water is much slower, with up to 300% swelling in water and up to 100% swelling in saline water. Significant leaching of the organic WA from the EPDM vulcanizates to the water phase occurs. Some combinations of WAs show synergetic effects for swelling in water. To our knowledge, such a systematic study of hybrid swelling elastomers constitutes a novelty in the open literature.

Curing, thermal, tensile and flammability characteristics of sepiolite/ethylene propylene diene monomer rubber composites with glut palmitate salt and silane coupling agents

“…The EPDM is also known for its ability to contain high quantities of fillers and oils. [2] EPDM is commonly added with fillers such as natural fiber, [3] carbon black, [4] silica [5] and hydroxyapatite. [6,7] Among various fillers used to produce rubber composites, silica and carbon black are widely used in the preparation and production of elastomeric composites, with the primary goal of improving mechanical and thermal properties while also lowering production costs and, in some cases, the weight of the final rubber products.…”

“…It is also known as the hydrated magnesium silicate. It is one of the clay minerals in the 2:1 phyllosilicate family with the half unit cell chemical formula of Mg 8 Si 12 O 30 (OH) 4 . 12 H 2 O.…”