| Polymer foam has long been used in the field of structural, insulation and damping areas because of its excellent properties. However, the applied research on polymer foams is ahead of basic research through the years, the compounding and processing of foaming technology mostly depend on experience and plenty of experiments. Therefore, it is necessary to study the decomposition of blowing agent qualitatively and quantitatively, to study the match of blowing process between crosslinking process.Ethylene-Butene copolymer (ENR) is a new type thermoplastic elastomer polymerized by metallocene catalyst and industrially produced by DOW Chemical Company. In this paper, we selected ENR as matrix material, azodicarbonamide(AC) as blowing agent, dicumyl peroxide (DCP) as crosslinking agent. The decomposition characteristics of AC in ENR compound were determined qualitatively and quantitatively. Furthermore, the preparation and properties of ENR foam materials were studied in detail, the resilience improvement of low density polyethylene (LDPE) foam was achieved by incorporating ENR as the elastic component.At first, the ENR/AC compound was prepared by blending AC in ENR matrix in the mixer of HAKKE rheometer. The decomposition characteristics of blowing agent AC in ENR were comprehensively studied by FTIR,TGA and DSC analyses. The results show that there are three steps during the decomposition process of AC at a constant heating rate and 63.7wt% gaseous product is released from AC. The onset decomposition temperature (Tonset) of AC decreases with addition of Zinc Oxide or Zinc Stearate as activating agent in ENR matrix, the optimum ratio of AC to Zinc oxide and Zinc Stearate are 1:1 and 1:0.4 respectively. Combination of Zinc Oxide with Zinc Stearate is more effective for the activation of AC. DCP has little effect on the decomposition of AC, just make the Tonset decrease slightly.Blowing curves and crossinking curves of ENR/AC/activating agent compounds were determined at the moving die rheometer. The results show that the optimum range of the foaming and crosslinking temperature is between 160°C and 180°C. The best mechanical properties of ENR foam material was obtained at temperature 170°C. The density of ENR foam decreased with the increasing AC content, and density of 0.060 g/cm3 was prepared successfully with addition of adding 10phr AC. Morphology observation shows that the cell structure of the ENR foam is closed-cell structure. The cell diameter decreases with increasing AC content, and open-cell structure forms with addition of more than 9phr AC. The compressive behavior of ENR foam was investigated through compressive stress-strain curves. The results show that foams have better energy absorption efficiency (E) while density decreased. The compressive stress-strain curves show that ENR foam could improve the compression-resilience of LDPE foam.In this paper, useful methods to study the decomposition behavior of blowing agents are given, a lot of parameters for formulation design and processing conditions of ENR foams are provided, a new way to improve compression-resilience of LDPE foam is explored. All the results have both theoretical and practical significance for foaming technology.
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