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Microporous polymer foam known as \used in various fields. Currently, industrial production of low-density polyethylene (LDPE) / ethylene-vinyl acetate copolymer (EVA) blend foam generally use a chemical blowing agent and chemical cross-linking agent, there is foam uneven foaming agent residues and environmental The unfriendly and other issues. In this paper, the green supercritical CO 2 foam technology, with 60Coγ Irradiation Modification of LDPE / EVA blends, to investigate the structure and performance of the irradiation of LDPE / EVA blends as well as their hair bubble behavior, but also to explore the the supercritical CO 2 foaming process factors blends LDPE / EVA foam behavior. The specific results of the study are summarized as follows: γ-ray irradiation modified the structure and properties of LDPE / EVA blends using differential scanning calorimetry (DSC), advanced rheological expansion system (ARES), hot gravimetric analysis (TG), Fourier transform infrared spectroscopy (FT-IR) analysis tools were used to characterize the structure and properties of the blend. The results show that: after the irradiation treatment, the gel content of the blend is increased, and the addition of the EVA reinforced LDPE crosslinked, the degree of crosslinking of the blend increased with increasing EVA content; same time, irradiation, LDPE / EVA blends, the melting point and degree of crystallinity is decreased slightly, the viscosity characteristics are improved, the increase in viscosity, the improvement of thermal stability, but the impact of irradiation cross-linking the main chain structure for the chemical blend. Γ-ray irradiation for the foaming behavior of LDPE / EVA blends, and characterized using scanning electron microscopy (SEM), and other means of crosslinked LDPE / EVA blend foam morphology and volume expansion rate . The results show that: compared with the non-irradiated crosslinked LDPE / EVA blends foam cell morphology of irradiation crosslinked LDPE / EVA blends better, more uniform pore size, and a wider range of the foaming temperature sample at 130oC maintained good cell morphology. Crosslinked appropriately able to narrow the aperture of the cell, increase the pore density, excessive crosslinking, and the pore size of the foam hole pairs distribution phenomenon appears. In the same time, the EVA content of 10%, the pore size of the foam holes minimum pore density. The EVA additive amount of 30%, the blend foam can reach the maximum volume expansion coefficient. Supercritical CO 2 foaming process factors foaming behavior of the crosslinked LDPE / EVA blends. The results showed that: a microporous morphology of the foaming temperature and the foaming pressure of the blend significantly affected, reducing foaming temperature and increase the foaming pressure can reduce the pore size of the bubble holes and improving the pore density of the foam holes. By optimizing the process parameters, can be prepared by a different pore size of the microporous material, the foaming temperature is 105 oC, the foaming pressure of 26 MPa, the bubble can be prepared by a pore density greater than 10 8 cm < sup> -3 of microporous materials.
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