Melt fracture reduction
    4.
    发明授权
    Melt fracture reduction 失效
    熔体断裂减少

    公开(公告)号:US5854352A

    公开(公告)日:1998-12-29

    申请号:US803319

    申请日:1997-02-21

    摘要: The extrusion of thermoplastic polyolefin, especially linear low density polyethylene (LLDPE) is improved by the use of a processing additive comprising a blend of a thermoplastic acrylic polymer and a fluorocarbon polymer. In a preferred embodiment, the processing additive is a homogeneous blend of a thermoplastic styrene/methyl methacrylate polymer and a thermoplastic copolymer of vinylidene fluoride and hexafluoropropylene. The polyolefin extrudates produced according to this invention have reduced levels of melt fracture when extruded in conventional polymer extrusion equipment.

    摘要翻译: 热塑性聚烯烃,特别是线性低密度聚乙烯(LLDPE)的挤出通过使用包含热塑性丙烯酸类聚合物和氟碳聚合物的共混物的加工添加剂来改进。 在优选的实施方案中,加工添加剂是热塑性苯乙烯/甲基丙烯酸甲酯聚合物和偏二氟乙烯和六氟丙烯的热塑性共聚物的均匀共混物。 根据本发明生产的聚烯烃挤出物在常规聚合物挤出设备中挤出时具有降低的熔体断裂水平。

    CONTINUOUS ETHYLENE TETRAMERIZATION PROCESS
    6.
    发明申请
    CONTINUOUS ETHYLENE TETRAMERIZATION PROCESS 有权
    连续乙烯四面体方法

    公开(公告)号:US20150284303A1

    公开(公告)日:2015-10-08

    申请号:US14443838

    申请日:2013-12-04

    IPC分类号: C07C2/34

    摘要: A continuous flow process for the oligomerization of ethylene using a chromium catalyst having a phosphorus-nitrogen-phosphorus (“P—N—P”) ligand provides high selectivity to the desired tetramer (1-octene) with reduced production of coproduct C10+ oligomers. Prior art processes that maximize catalyst activity have provided comparatively poor product selectivity. In particular, the production of larger amounts of C10+ oligomers have been observed under conditions that maximize activity. The present process resolves this problem through the use of a combination of low catalyst concentration and by limiting the octene concentration in the reactor.

    摘要翻译: 使用具有磷 - 氮 - 磷(“P-N-P”)配体的铬催化剂使乙烯低聚的连续流动方法对所需的四聚体(1-辛烯)提供了高选择性,同时产生了副产物C10 +低聚物。 使催化剂活性最大化的现有技术方法提供了较差的产物选择性。 特别地,在活性最大化的条件下观察到产生较大量的C10 +低聚物。 本方法通过使用低催化剂浓度和限制反应器中辛烯浓度的组合来解决这个问题。

    Heterogeneous metallocene catalyst
    10.
    发明授权
    Heterogeneous metallocene catalyst 有权
    异质金属茂催化剂

    公开(公告)号:US06235671B1

    公开(公告)日:2001-05-22

    申请号:US09292039

    申请日:1999-04-14

    IPC分类号: B01J3100

    摘要: A heterogeneous catalyst for olefin polymerization is prepared by spray drying a mixture of a metallocene catalyst, a cocatalyst and a hydrotalcite. It Preferred hydrotalcites are magnesium-aluminum hydroxy carbonates. The catalysts are very active for ethylene polymerization. The hydrotalcite used in this invention are generally defined by the formula: (Mg1−x Alx(OH)2)n+An−x/n·m H2O wherein X is from 0 to 0.5, m is from 0 to 20 and An− is an anion having a charge of n. Preferred hydrotalcites are those in which the anion A is a carbonate and which have been dried of adsorbed water.

    摘要翻译: 通过喷雾干燥茂金属催化剂,助催化剂和水滑石的混合物来制备用于烯烃聚合的非均相催化剂。 优选的水滑石是羟基碳酸镁铝。 催化剂对于乙烯聚合是非常有活性的。 本发明中使用的水滑石通常由下式定义:其中X为0至0.5,m为0至20,An-为负电荷为n的阴离子。 优选的水滑石是阴离子A是碳酸盐并且已被吸附的水干燥的那些。