Mechanical Properties of Silicone Rubber Enhanced Microcellular EPDM Foams Based on Supercritical CO₂Foaming Technology

Abstract

Microcellular ethylene‐propylene‐diene monomer (EPDM) foams derived from miniaturizing the cellular structure can improve mechanical properties of traditional EPDM foams. It is a current challenge that microcellular EPDM foams prepared by supercritical CO2 foaming technology cannot undergo the post‐crosslinking process due to the disappearance of cellular structure, which strongly restricts the development of the mechanical properties of EPDM foams. Hence, a scalable and blending route by selecting the silicone rubber (SR) with different crosslinking temperature compared to EPDM is developed to improve mechanical properties of EPDM foams. During the pre‐crosslinking process of EPDM, SR forms a complete crosslinking network, which can make up for the strength of EPDM without the post‐crosslinking. Meanwhile, the silica can reduce the domain size of SR and enhance the compatibility between EPDM and SR. As expected, the addition of SR improves the storage modulus, viscosity and matrix strength of EPDM, which shows enhanced mechanical properties of EPDM foams. When the foam density is basically the same, the tensile strength and compressive strength of SR/EPDM foam are increased by 461% and 283% respectively compared with that of EPDM foam. Finally, the maximum tensile strength and compressive strength (40% strain) of SR/EPDM foam achieves 3.58 MPa and 0.59 MPa, respectively.

Fabrication of Triblock Elastomer Foams for Oil Absorption Applications: Effects of Crosslinking, Composition, and Rheology Factors

“…This is because, EPDM is a widely used and commercially available TPE that exhibits a high resemblance with SEBS in terms of the chemical structure and physical properties, such as hardness and rheology, to generate a compatible blend . Moreover, EPDM has sufficient melt strength and appealing physicochemical properties to generate high-performance elastomer foams with excellent mechanical properties, outstanding resistance to chemicals, heat, and weathering, and ease of processing and creating porous structure. − Last, adopting EPDM enables crosslinking in the polymer system on account of the unsaturated double bond [from ethylidene-2-norbornene (ENB)] on its structure. The crosslinking allows finetuning of the melt strength to facilitate foaming expansion and foam stability, as well as to enhance the thermal, mechanical, and rheological properties. , …”

Recycling NR/SBR waste using probe sonication as a new devulcanizing method; study on influencing parameters

“…In fact, during reclaiming a rubber, thermal/mechanical stresses are encountered to ground waste rubber particles that cause fracture in the polymer backbone and so signicant decrement in the mechanical properties of the recycled product. [15][16][17] On this basis, an effective method is needed for recycling waste rubbers. Literature review among published articles in this eld shows that devulcanization (i.e.…”

“…In fact, during reclaiming a rubber, thermal/mechanical stresses are encountered to ground waste rubber particles that cause fracture in the polymer backbone and so significant decrement in the mechanical properties of the recycled product. 15–17…”