Propylene polymers for films
    8.
    发明授权
    Propylene polymers for films 有权
    丙烯聚合物薄膜

    公开(公告)号:US06583227B2

    公开(公告)日:2003-06-24

    申请号:US09800238

    申请日:2001-03-06

    IPC分类号: C08L2314

    摘要: This invention relates generally to crystalline propylene polymers, to methods for their production and to methods for their use in film applications. Specifically, this invention relates to crystalline propylene polymers comprising both propylene homopolymer and propylene copolymer. The compositions are prepared using metallocene catalyst systems comprising at least two metallocenes in a polymerization process that involves the sequential or parallel polymerization of propylene homopolymer and copolymer using propylene with a small amount of comonomer, preferably ethylene. The polymerization is catalyzed by a dual metallocene catalyst system. The resulting polymers have a broad, bimodal molecular weight distribution. The resulting polymers are excellent for use in the production of biaxially oriented films or non-oriented films. Films prepared with these propylene polymers have a significantly broader processability range and can be evenly stretched at lower temperature compared to films prepared from traditional propylene polymer.

    摘要翻译: 本发明一般涉及结晶丙烯聚合物,其制备方法及其用于膜应用的方法。 具体地说,本发明涉及包含丙烯均聚物和丙烯共聚物的结晶丙烯聚合物。 在聚合过程中使用包含至少两种金属茂的茂金属催化剂体系制备组合物,其涉及使用丙烯与少量共聚单体,优选乙烯的丙烯均聚物和共聚物的顺序或平行聚合。 聚合由双茂金属催化剂体系催化。 所得聚合物具有宽的双峰分子量分布。 所得聚合物非常适用于制备双轴取向膜或非取向膜。 用这些丙烯聚合物制备的膜具有显着更宽的加工性能范围,与传统丙烯聚合物制备的膜相比,可以在较低的温度下均匀地拉伸。