Polymer Extrusion Process
    5.
    发明公开

    公开(公告)号:US20230202089A1

    公开(公告)日:2023-06-29

    申请号:US17919987

    申请日:2021-04-26

    IPC分类号: B29C48/30 B29C48/00

    摘要: In the manufacture of extruded polymers there are a number of surface defects referred to as sharkskin, snakeskin and orange peel which all generally relate to the rheology of the polymer melt. A severe form of surface defect is “melt fracture” which is believed to result when the shear rate at the surface of the polymer is sufficiently high that the surface of the polymer begins to fracture. That is, there is a slippage of the surface of the extruded polymer relative to the body of the polymer melt. The surface generally can't flow fast enough to keep up with the body of the extrudate and a fracture in the melt occurs generally resulting in a severe loss of surface properties for the extrudate. A polymer extension process is disclosed wherein these undesirable surface defects are eliminated.