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    Electronic component encapsulated with a composition comprising a polymer which is capable of forming an anisotropic melt phase and substantially incapable of further chain growth upon heating
    44.
    发明授权
    Electronic component encapsulated with a composition comprising a polymer which is capable of forming an anisotropic melt phase and substantially incapable of further chain growth upon heating 失效
    封装有包含能够形成各向异性熔融相并且在加热时基本上不能进一步链增长的聚合物的组合物的电子部件

    公开(公告)号：US4720424A

    公开(公告)日：1988-01-19

    申请号：US872007

    申请日：1986-06-09

    申请人： Nancy C. Eickman ,  Charles E. McChesney ,  Gary E. Williams ,  Hyun-Nam Yoon

    发明人： Nancy C. Eickman ,  Charles E. McChesney ,  Gary E. Williams ,  Hyun-Nam Yoon

    IPC分类号： C08G63/60 ,  C08K3/36 ,  C08L77/12 ,  H01B3/42 ,  H01L23/29 ,  B32B5/16 ,  B32B27/06 ,  B32B27/34 ,  B32B27/36

    CPC分类号： H01L23/293 ,  C08G63/605 ,  C08K3/36 ,  C08L77/12 ,  H01B3/42 ,  H01L2924/0002 ,  Y10T428/239 ,  Y10T428/25 ,  Y10T428/259 ,  Y10T428/31725 ,  Y10T428/31786

    摘要： An improved thermoplastic molding composition is provided which is particularly suited for use in the impervious void-free encapsulation on a relatively expeditious basis of an electronic component wherein the preformed electronic component is positioned in a mold cavity prior to the introduction of the molding composition via injection molding. The molding composition comprises a melt processable thermotropic liquid crystalline polymer which is of a relatively low weight average molecular weight of approximately 4,000 to 25,000 (e.g. approximately 4,000 to 10,000) and which is substantially incapable of further chain growth upon heating. Uniformly dispersed within the liquid crystalline polymer is approximately 40 to 80 percent by weight (e.g. approximately 50 to 75 percent by weight) of a particulate inorganic material (preferably of silicon dioxide) which serves to advantageously decrease its volumetric coefficient of thermal expansion and to advantageously increase its thermal conductivity. In a preferred embodiment the electronic component which is encapsulated is a semiconductor device, such a relatively delicate quad or dual-in-line integrated circuit device which is assembled onto a flat prestamped lead frame or other conductive device having a plurality of leads which extend outside the area which is encapsulated. The resulting encapsulated electronic component is well protected in spite of the relatively low molecular weight of the liquid crystalline polymer and is capable of satisfactory service for an extended period of time even if adverse environmental conditions are encountered. A rugged commonly nonburning and relatively inexpensive package is provided.

    摘要翻译： 提供了一种改进的热塑性模塑组合物，其特别适合于在电子部件的相对快速的基础上用于不透水的无空隙的封装，其中在通过注射引入模塑组合物之前将预成型的电子部件定位在模腔中 成型。 模塑组合物包含熔体加工的热致液晶聚合物，其具有约4,000至25,000（例如约4,000至10,000）的相对低的重均分子量，并且其在加热时基本上不能进一步链生长。 均匀分散在液晶聚合物内的颗粒无机材料（优选为二氧化硅）为约40至80重量％（例如约50至75重量％），其用于有利地降低其体积热膨胀系数并且有利地 增加其导热性。 在优选实施例中，封装的电子部件是半导体器件，这种相对精密的四线或双列直插集成电路器件被组装到扁平预压引线框架或其它导电器件上，该器件具有多个引线， 被封装的区域。 尽管液晶聚合物的分子量相对较低，但是所得到的封装的电子部件被很好地保护，并且即使遇到不利的环境条件，也能够长时间地满足服务。 提供了坚固的通常不燃烧和相对便宜的包装。

    Process for forming thermally stable thermotropic liquid crystalline polyesters of predetermined chain length utilizing aromatic hydroxyl monomer and/or aromatic amine monomer
    45.
    发明授权
    Process for forming thermally stable thermotropic liquid crystalline polyesters of predetermined chain length utilizing aromatic hydroxyl monomer and/or aromatic amine monomer 失效
    使用芳族羟基单体和/或芳族胺单体形成具有预定链长的热稳定的热致液晶聚酯的方法

    公开(公告)号：US4567247A

    公开(公告)日：1986-01-28

    申请号：US611299

    申请日：1984-05-17

    申请人： Hyun-Nam Yoon

    发明人： Hyun-Nam Yoon

    IPC分类号： C08G63/00 ,  C08G63/06 ,  C08G63/60 ,  C08G63/664 ,  C08G63/78 ,  C08G69/00 ,  C08G69/44 ,  C09K19/38

    CPC分类号： C08G63/605 ,  C08G69/44 ,  C09K19/3809

    摘要： An improved polymerization process is provided for the formation of a polyester which is capable of forming an anisotropic melt phase and which optionally may include amide linkages. An approximately 0.25 to 4 percent molar excess of aromatic hydroxyl monomer and/or aromatic amine monomer and/or an esterified and/or amidated derivative thereof is provided in the polymerization zone during the polymerization reaction. Such monomer imparts dioxyaryl, diaminoaryl, or oxyaminoaryl units to the interior of the resulting polymer chains and causes the polymer chains to terminate in hydroxyl end groups and/or an esterified derivative thereof and/or amino end groups and/or an amidated derivative thereof wherein the polymer chains achieve a predetermined average chain length through the depletion of other monomers present in the polymerization zone. The resulting polyester unlike the usual product of the prior art is substantially incapable of additional chain growth upon subsequent heating and accordingly may be relied upon to maintain a substantially constant viscosity during melt processing regardless of the duration of heating.

    摘要翻译： 提供改进的聚合方法用于形成能够形成各向异性熔融相的聚酯，并且任选地可以包括酰胺键。 在聚合反应期间，在聚合区域中提供约0.25至4％摩尔过量的芳族羟基单体和/或芳族胺单体和/或其酯化和/或酰胺化衍生物。 这样的单体将二芳基，二氨基芳基或氧氨基芳基单元赋予所得聚合物链的内部，并使聚合物链终止于羟基端基和/或其酯化衍生物和/或氨基端基和/或其酰胺化衍生物，其中 通过消耗聚合区中存在的其它单体，聚合物链达到预定的平均链长。 所得聚酯与现有技术的通常产品不同，在随后的加热中基本上不能增加链条生长，因此可以依赖于在熔融加工期间保持基本恒定的粘度，而不管加热的持续时间如何。

    Process for forming thermally stable thermotropic liquid crystalline polyesters of predetermined chain length
    46.
    发明授权
    Process for forming thermally stable thermotropic liquid crystalline polyesters of predetermined chain length 失效
    用于形成具有预定链长的热稳定性热致液晶聚酯的方法

    公开(公告)号：US4539386A

    公开(公告)日：1985-09-03

    申请号：US517865

    申请日：1983-07-27

    申请人： Hyun-Nam Yoon

    发明人： Hyun-Nam Yoon

    IPC分类号： C08G18/00 ,  C08G18/16 ,  C08G63/00 ,  C08G63/06 ,  C08G63/18 ,  C08G63/19 ,  C08G63/60 ,  C08G63/68 ,  C08G63/685 ,  C08G63/78 ,  C08G69/00 ,  C08G69/44

    CPC分类号： C08G63/605 ,  C08G69/44

    摘要： An improved polymerization process is provided for the formation of a polyester which is capable of forming an anisotropic melt phase and which optionally may include amide linkages. An approximately 0.25 to 4 percent molar excess of aromatic dicarboxylic acid monomer (e.g. terephthalic acid) and/or an esterified derivative thereof is provided in the polymerization zone during the polymerization reaction. Such monomer imparts dicarboxyaryl units to the interior of the resulting polymer chains and causes the polymer chains to terminate in carboxylic acid end groups and/or an esterified derivative thereof wherein the polymer chains achieve a predetermined average chain length through the depletion of other monomers present in the polymerization zone. The resulting polyester unlike the usual product of the prior art is substantially incapable of additional chain growth upon subsequent heating and accordingly may be relied upon to maintain a substantially constant viscosity during melt processing regardless of the duration of heating.

    摘要翻译： 提供改进的聚合方法用于形成能够形成各向异性熔融相的聚酯，并且任选地可以包括酰胺键。 在聚合反应期间，在聚合区域中提供了约0.25至4％摩尔过量的芳族二羧酸单体（例如对苯二甲酸）和/或其酯化衍生物。 这样的单体将二羧基芳基单元赋予所得聚合物链的内部，并使聚合物链终止于羧酸端基和/或其酯化衍生物中，其中聚合物链通过其中存在的其它单体的消耗而达到预定的平均链长 聚合区。 所得聚酯与现有技术的通常产品不同，在随后的加热中基本上不能增加链条生长，因此可以依赖于在熔融加工期间保持基本恒定的粘度，而不管加热的持续时间如何。