高发泡倍率三元乙丙弹性体材料模压发泡研究

Investigation of Mold Foaming of EPDM Elastomer with High Expansion Ratio

用模压发泡法制备了三元乙丙弹性体(EPDM)发泡材料,研究了AC发泡剂用量、氧化锌(ZnO)用量、过氧化二异丙苯(DCP)用量以及发泡温度、发泡压力、发泡时间等工艺参数对EPDM泡沫表观密度和力学性能等的影响。结果表明:随着AC发泡剂用量的增加,EPDM泡沫的力学性能和泡沫表观密度缓慢下降。随着DCP用量的增加,泡沫的拉伸强度和撕裂强度逐渐增大。DCP用量为0.5份时发泡倍率达到最大,为8.2。ZnO用量对泡沫力学性能影响不大。发泡温度为170℃时泡沫表观密度达到最小。随着发泡压力逐步升高,泡沫表观表观密度缓慢上升。发泡压力为0.5MPa和5MPa时发泡倍率超过8。发泡时间为12 min时表观密度最低,为0.124 g/cm3,发泡倍率达到最大8.2。扫描电子显微镜观察显示,EPDM泡沫多为闭孔结构。

The ethylene propylene diene monomer(EPDM)foam was prepared by molding method.The influence various factors such as AC foaming agent,zinc oxide(ZnO),dicumyl peroxide(DCP),foaming temperature,pressure and time on density and mechanical properties of EPDM foam were investigated.The results show that mechanical properties and density of EPDM foam decrease gradually as the increase of AC foaming agent.As DCP content increases,tensile strength and tear strength of EPDM foam increase gradually.The expansion ratio reaches the maximum,which is 8.2 when DCP content is 0.5 phr.The experiments show content of ZnO has little effect on mechanical properties of EPDM foam.The density of EPDM foam reaches the minimum when the temperature is 170℃.The density of EPDM foam increases gradually when foaming pressure increases.The expansion ration of the EPDM foam exceeds 8 when pressure is 0.5 and 5 MPa respectively.The density of EPDM foam has lowest value when foaming time is 12 min,which is 0.124 g/cm3,and the expansion ratio arrives the highest value 8.2.Scanning electron microscope shows the EPDM foam mainly has a structure with closed cells.