Process for forming an expanded porous tetrafluoroethylene polymer
    1.
    发明授权
    Process for forming an expanded porous tetrafluoroethylene polymer 失效
    形成膨体多孔四氟乙烯聚合物的方法

    公开(公告)号:US5098625A

    公开(公告)日:1992-03-24

    申请号:US628322

    申请日:1990-12-17

    摘要: A process for preparing an improved expanded porous polytetrafluorethylene product having a higher density and improved cold flow properties and prepared from a paste formed from a polytetrafluoroethylene resin and a lubricant. The method includes extruding the paste through an extrusion die at a reduction ratio of less than 100, calendering the extrudate, removing the lubricant, and heating the extrudate to a temperature greater than the crystalline melting point of polytetrafluoroethylene but generally below the temperature at which thermal decomposition becomes appreciable while concurrently expanding the extrudate to at least twice its original length.

    摘要翻译: 一种制备改进的膨胀多孔聚四氟乙烯产品的方法,其具有更高的密度和更好的冷流动性能,并且由由聚四氟乙烯树脂和润滑剂形成的糊料制备。 该方法包括以小于100的压缩比将挤压模挤出挤出模具,压延挤出物,除去润滑剂,并将挤出物加热至高于聚四氟乙烯的结晶熔点的温度,但通常低于热 分解变得明显,同时将挤出物膨胀至其原始长度的至少两倍。

    Production method of a polytetrafluoroethylene sheet or film
    5.
    发明授权
    Production method of a polytetrafluoroethylene sheet or film 有权
    聚四氟乙烯片或薄膜的制造方法

    公开(公告)号:US06702971B2

    公开(公告)日:2004-03-09

    申请号:US09985385

    申请日:2001-11-02

    IPC分类号: B29C4712

    摘要: To provide a method of producing a uniaxially stretched polytetrafluoroethylene gasket tape, which comprises: (1) a step for preparing a paste comprising a mixture of a polytetrafluoroethylene powder obtained by emulsion polymerization and an extrusion aid, (2) a step for extruding the paste by means of an extruder equipped with a die which has plural separators inside an orifice thereof having a rectangular cross section, (3) a step for rolling, in the extruding direction, an extrudate having slit lines to give a rolled polytetrafluoroethylene sheet, (4) a step for uniaxially stretching the rolled sheet in the rolling direction after removing the extrusion aid from the rolled sheet, and (5) a step for heat-treating the obtained uniaxially stretched polytetrafluoroethylene sheet. The die of the extruder has plural sheet-like separators in the orifice thereof having a rectangular cross section. The separators are mounted so that free ends thereof are located at a point exceeding a center point of a long side of the orifice, and function to provide slit lines inside the extrudate in parallel with the long side of the orifice. The high performance inexpensive PTFE gasket tape is produced by the uniaxially stretching method and has properties equal to those of biaxially stretched PTFE gasket tape.

    摘要翻译: 提供一种单轴拉伸聚四氟乙烯垫片带的制造方法,其特征在于,包括:(1)制备包含通过乳液聚合获得的聚四氟乙烯粉末与挤出助剂的混合物的糊料的步骤,(2)挤出糊料的步骤 (3)在挤出方向上轧制具有切割线的挤出物以得到轧制的聚四氟乙烯片材的步骤(4),(4)在具有矩形横截面的孔中具有多个分离器的模具, )从轧制板除去挤出助剂后,在轧制方向上单轴拉伸轧制板的工序,(5)对所得单轴拉伸聚四氟乙烯片进行热处理的工序。 挤出机的模具在其孔中具有多个片状隔离物,其截面为矩形。 分离器被安装成使得其自由端位于超过孔的长边的中心点的点上,并且用于在挤出物内部与孔的长边平行地提供切割线。 高性能廉价的PTFE垫片带通过单向拉伸法制造,具有与双轴拉伸PTFE垫片带的性能相同的性能。

    Porous polytetrafluoroethylene molded article
    6.
    发明授权
    Porous polytetrafluoroethylene molded article 失效
    多孔聚四氟乙烯成型品

    公开(公告)号:US6080472A

    公开(公告)日:2000-06-27

    申请号:US103722

    申请日:1998-06-24

    IPC分类号: B29C55/00 C08J5/18 B32B3/00

    摘要: To provide a porous polytetrafluoroethylene sheet which has excellent cold flow resistance and is used suitably for gaskets and a highly densified polytetrafluoroethylene sheet which has high tensile strength and flex life and is used suitably for diaphragms. The porous polytetrafluoroethylene sheet is produced from a polytetrafluoroethylene material having a microstructure of nodes interconnected by fibrils and has MTS of from 3,000 to 12,000 psi and C.I. of 0.02 to 0.20 g/cc/psi. The highly densified polytetrafluoroethylene sheet is produced by compression-molding the porous polytetrafluoroethylene sheet and then sintering completely. The porous polytetrafluoroethylene sheet is also laminated with a sheet of other material to provide a composite polytetrafluoroethylene molded article.

    摘要翻译: 为了提供耐冷流动性优异的多孔聚四氟乙烯片材,适用于垫片和高度致密化的聚四氟乙烯片材,其具有高拉伸强度和挠曲寿命,并适用于隔膜。 多孔聚四氟乙烯片材由具有通过原纤维互连的节点的微结构的聚四氟乙烯材料制成,并且具有3,000至12,000psi的MTS和C.I. 为0.02〜0.20g / cc / psi。 高密度聚四氟乙烯片材是通过压缩多孔聚四氟乙烯片材然后完全烧结制成的。 多孔聚四氟乙烯片也与其他材料片层压,以提供复合聚四氟乙烯模塑制品。