摘要:
A bi-layer covering sheath has a foamable polymeric inner layer, and a non-foamable non-heat-shrinkable polymeric outer layer surrounding and in intimate contact with the inner layer; the outer layer having a melting point that is at least 60° above the melting point of the inner layer, and the thickness and mechanical strength of the outer layer being such that the sheath retains substantially constant outer dimensions at a temperature sufficient to cause foaming of the inner layer. These sheaths are tubes for covering, generally, elongated substrates such as tubes, rods, wires, and cables, especially tubes, and caps for covering an end of such substrates.
摘要:
A conductive polymer composition containing a particulate conductive filler dispersed in a polymeric component. The polymeric component comprises a first polymer which (i) is present in an amount 25 to 75% by weight of the total polymeric component, and (ii) is polyethylene, and a second polymer which (i) is present in an amount 25 to 75% by weight of the total polymeric component, and (ii) comprises units derived from a first monomer which is ethylene and a second monomer which is an alkyl acrylate having the formula --CH.sub.2 .dbd.CHCOOC.sub.m H.sub.2m+1, where m is at least 4. The resulting composition is useful in preparing electrical devices, e.g. circuit protection devices, which have lower resistivities, higher PTC anomalies, and better thermal and electrical stability than devices comprising conventional conductive polymer compositions.
摘要翻译:包含分散在聚合物组分中的颗粒状导电填料的导电聚合物组合物。 聚合物组分包含第一聚合物,其中(i)以总聚合物组分的25至75重量%的量存在,和(ii)是聚乙烯,和第二聚合物,其中(i)以25至 75重量%的总聚合物组分,和(ii)包含衍生自作为乙烯的第一单体的单元和具有式-CH 2 = CHCOOC m H 2 m + 1的丙烯酸烷基酯的第二单体,其中m至少为4。 所得组合物可用于制备电气装置,例如 电路保护装置,其具有比包含常规导电聚合物组合物的装置更低的电阻率,更高的PTC异常以及更好的热和电稳定性。
摘要:
A foamable copolymer based coupling is provided for securely affixing a light emitting glass lamp in a metal base to form a lamp assembly. The copolymer is preferably selected from ethylene vinyl acetate, ethylene methyl acrylate, and combinations thereof. The foamable coupling may be placed around one end of the glass lamp or in the lamp base before the lamp and base are matingly engaged. The assembled lamp is then heated to a temperature, which causes the foamable coupling to expand and securely affix the lamp in the base.
摘要:
A process for manufacturing a composite polymeric circuit protection device in which a polymeric assembly is provided and is then subdivided into individual devices (2). The assembly is made by providing first and second laminates (7,8), each of which includes a laminar polymer element having at least one conductive surface, providing a pattern on at least one of the conductive surfaces on one laminate, securing the laminates in a stack (1) in a desired configuration, at least one conductive surface of at least one of the laminates forming an external conductive surface (3) of the stack, and making a plurality of electrical connections (31,51) between a conductive surface of the first laminate and a conductive surface of the second laminate. The laminar polymer elements may be PTC conductive polymer compositions, so that the individual devices made by the process exhibit PTC behavior. Additional electrical components may be attached directly to the surface of the device or assembly.
摘要:
A foamable copolymer based coupling is provided for securely affixing a light emitting glass lamp in a metal base to form a lamp assembly. The copolymer is preferably selected from ethylene vinyl acetate, ethylene methyl acrylate, and combinations thereof. The foamable coupling may be placed around one end of the glass lamp or in the lamp base before the lamp and base are matingly engaged. The assembled lamp is then heated to a temperature, which causes the foamable coupling to expand and securely affix the lamp in the base.
摘要:
A circuit protection device for protecting batteries is formed from a resistive element composed of a PTC conductive polymer composition and two electrodes. The device has a resistive element thickness of 0.025 to 0.20 mm; a crosslinking level equivalent to 1 to 20 Mrads; a surface area of at most 120 mm.sup.2 ; a resistance at 20.degree. C., R.sub.20, of at most 0.030 ohm; and a resistivity at 20.degree. C., .rho..sub.20, of at most 2.0 ohm-cm. Devices of the invention are sufficiently small to be easily inserted into an assembly comprising a battery, particularly a rechargeable battery, and the device. Such assemblies are used for powering portable electronic equipment such as cellular telephones.
摘要:
A surface mount circuit protection device includes a laminar PTC resistive element having first and second major surfaces and a thickness therebetween. A first electrode layer substantially coextensive the first surface is formed of a first metal material of a type adapted to be soldered to a printed circuit substrate. A second electrode layer formed at the second major surface includes structure forming or defining a weld plate. The metal weld plate has a thermal mass and thickness capable of withstanding resistance micro spot welding of a strap interconnect without significant resultant damage to the device. The device is preferably surface mounted to a printed circuit board assembly forming a battery protection circuit connected to a battery/cell by battery strap interconnects, wherein one of the battery strap interconnects is micro spot welded to the weld plate of the device.
摘要:
A foamable copolymer based coupling is provided for securely affixing a light emitting glass lamp in a metal base to form a lamp assembly. The copolymer is preferably selected from ethylene vinyl acetate, ethylene methyl acrylate, and combinations thereof. The foamable coupling may be placed around one end of the glass lamp or in the lamp base before the lamp and base are matingly engaged. The assembled lamp is then heated to a temperature, which causes the foamable coupling to expand and securely affix the lamp in the base.
摘要:
An electrical resistive device in which an element composed of a conductive polymer is positioned in contact with the surface layer of one or more metal electrodes. The metal electrode contains a base layer which includes a first metal, an intermediate metal layer which includes a metal that is different from the first metal, and a surface layer which (i) includes a second metal, (ii) has a center line average roughness {overscore (Ra)} of at least 1.3, and (iii) has a reflection density Rd of at least 0.60. The conductive polymer composition preferably exhibits PTC behavior density requirements, which may be, for example, circuit protection devices or heaters, have improved thermal and electrical performance over devices prepared with electrodes which do not meet the center line average roughness and reflection density requirements.
摘要:
A conductive polymer composition containing a particulate conductive filler dispersed in a polymeric component. The polymeric component comprises a first polymer which (i) is present in an amount 25 to 75% by weight of the total polymeric component, and (ii) is polyethylene, and a second polymer which (i) is present in an amount 25 to 75% by weight of the total polymeric component, and (ii) comprises units derived from a first monomer which is ethylene and a second monomer which is an alkyl acrylate having the formula --CH.sub.2 .dbd.CHCOOC.sub.m H.sub.2m+1 --, where m is at least 4. The resulting composition is useful in preparing electrical devices, e.g. circuit protection devices, which have lower resistivities, higher PTC anomalies, and better thermal and electrical stability than devices comprising conventional conductive polymer compositions.
摘要翻译:一种含有分散在聚合物组分中的颗粒状导电填料的导电聚合物组合物。 聚合物组分包含第一聚合物,其中(i)以总聚合物组分的25至75重量%的量存在,和(ii)是聚乙烯,和第二聚合物,其中(i)以25至 75重量%的总聚合物组分,和(ii)包含衍生自乙烯的第一单体的单元和具有式-CH 2 = CHCOOC m H 2 m + 1的丙烯酸烷基酯的第二单体,其中m为至少4 所得组合物可用于制备电气装置,例如 电路保护装置,其具有比包含常规导电聚合物组合物的装置更低的电阻率,更高的PTC异常以及更好的热和电稳定性。