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Expanded thermoplastic polyurethane (ETPU) foam materials with superelasticity for footwear application were developed and investigated. ETPU foams with different ratios of CO2/N2 as foaming agents and ETPU foams prepared by pure nitrogen foaming with different kinds of foaming additives were prepared by supercritical (Sc) foaming technology, which further made into sheet forms through the steam molding process. TPU foam exhibits better cell structure, crystallization performance, and mechanical strength with the increased CO2 proportion. Further, the foams using 25% CO2–75% N2 and 50% CO2–50% N2, showed a lower density and excellent resilience and cyclic-compression performance. However, an increase of N2 ratio improves the dimensional stability and compression set of the foam. The introduction of foaming aids enhances the interaction between Sc-N2 and TPU. The ETPU foam prepared under the same conditions has a smaller density and a larger expansion ratio. Especially the ETPU foam prepared by Sc-N2 using monofluorodichloroethane as the foaming assistant as a co-blowing agent, the decrease in cell size (from 117.9 to 19.6 μm) and density (from 0.175 to 0.139 g/cm3) has observed. The study revealed the high potential of these materials in footwear applications and offered sound evidence for mass production in the industry.

Fabrication of V2O5-WO3/TiO2 supported-SiC catalytic filters has been developed by using rotational coating method and discussed their NO conversion performances at different reaction temperature (150–380 °C). M3C catalytic filter (coated with the grinded catalyst solution of catalyst with particle size of 1.0 μm) showed the 99.9% NO conversion with the Nx-slip concentration below 15 ppm with the optimal temperature range from 230–350 °C, which is very satisfactory with the value approaching to the case of powder catalyst. The concentration of the catalyst coating solution optimized to 10 wt% (M310) to achieve the better NO conversion > 99.5%. An effect of ball milling on the catalytic coating solution has investigated to achieve the 99.9% NO conversion. The effect of varied V2O5 content on NO conversion has been studied. The activation temperature for > 99% conversion of 700 ppm NO gas shifted towards the lower one with the increase of the V2O5 content of V2O5-WO3/TiO2 supported SiC filter. M3V3 (3 wt% V2O5) is the best catalyst composition showed 100% NO conversion with the reaction temperature window 280–320 °C with less N2O formation below 20 ppm. However, M3V6 (6 wt% V2O5) showed the lowest reaction temperature as 240 °C for > 99% NO conversion.

Propylene/1-butene (PPB) copolymer foam materials are successfully prepared by supercritical CO2 and the effects of different 1-butene content on the mechanical, crystallization, foaming, and cushioning properties of prepared PPB foam material are investigated. The decrease in hardness value (from 90 to 67), tensile strength (from 37.8 MPa to 32.5 MPa), and bending strength (from 40.6 MPa to 34 MPa) of PPB materials along with the enhanced impact strength (from 3834.3 MJ/m2 to 6699.65 MJ/m2) are a result of high 1-butene content. The increased foaming ratio and broadened foaming temperature window of PPB materials achieved with increased 1-butene content. Energy absorption efficiency has enhanced (from 0.678 to 0.847), and ideal parameters also improved significantly (from 0.242 to 0.303) at the same density along with the cushioning performance of PPB foaming materials. Low-density, high 1-butene content PPB materials have a better energy absorption effect with a lower permissible stress.