In this paper, aramid fiber (AF)/ethylene‐propylene‐diene monomer (EPDM) microcellular foams added with different content of AF are prepared by the supercritical foaming method. The effect of the AF content on the rheological behavior, mechanical properties, thermal properties and cellular structure of the AF/EPDM microcellular foams has been systematically studied. The research illustrates that compared with pure EPDM, the AF/EPDM matrix has greater viscosity and modulus, which is conducive to reduce the cell size and increase its density. And the thermal stability of EPDM foams is improved with the addition of aramid fiber. Meanwhile, when the content of AF is added to 1 wt%, the AF/EPDM microcellular foam exhibits a relatively low thermal diffusion coefficient and apparent density with the thermal conductivity to 0.06 W/mK. When the AF is added to 5 wt%, the tensile strength of the AF/EPDM microcellular foam increases to 1.95 MPa, which is improved by 47% compared with that of the pure EPDM foam. Furthermore, when the compressive strain reaches to 50%, the compressive strength of the AF/EPDM microcellular foam is 0.48 MPa, improved by 296% compared with that of the pure EPDM foam.

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.

The supercritical foaming (SCF) method was proposed to conveniently fabricate superhydrophobic polydimethylsiloxane (PDMS) surface. The effect of foaming parameters on the cellular structure, wettability, mechanical properties and thermal properties was investigated. This work indicates that the microstructure plays an important role in the superhydrophobicity of the PDMS materials. When the cell size and cell wall size, respectively, reach to 103.6 and 29.7 μm, the water contact angle (WCA) of the microcellular PDMS foams can achieve the maximum value 158°, and the air occupies about 90.6% of the contact areas. Meanwhile, the tensile strength of superhydrophobic PDMS materials can reach to 0.81 MPa, indicating that the superhydrophobic PDMS materials are useful. Moreover, the superhydrophobic PDMS materials show good thermal stability and excellent adiabatic property. And the method is simple and convenient, which can be used for the preparation of the superhydrophobic surfaces.