发泡工艺对高发泡PP板材性能的影响

Effect of Foaming Parameters on Properties of Highly Foamed PP Boards

用双螺杆挤出机对聚丙烯(PP)进行硅烷交联改性,制备出了高熔体强度的PP;以偶氮二甲酰胺为发泡剂,用压制成型的方法制备了泡孔均匀、细密的发泡PP板材,研究了其冲击强度、弯曲强度和板材密度。结果表明,发泡剂用量、发泡调节剂用量、压制工艺条件对其性能有很大影响;当发泡剂的含量为2.5份(质量份,下同)、发泡调节剂用量为8份、压制成型温度为195℃、压力为20MPa、发泡时间为17min时,PP发泡板材的密度最低、力学性能最优、泡孔结构最细密、均匀。

PP was cross-linked with silane via twin-screw extrusion. Using AC as a blowing agent, a foamed PP board was prepared by compression molding in which bubbles were well distributed and cells were very meticulous. The effect of the processing parameters on the impact and bending strengths, and the density of the board were investigated. PP boards with optimal performance was obtained when the content of foaming agent was 2. 5 phr, the foam control agent was 8 phr, the molding temperature was 195 ℃, the pressure was 20 MPa, and the compression time was 17 min.