摘要:
Provided are novel compositions comprising a polyarylene sulfide and at least one tin additive comprising a branched tin(II) carboxylate selected from the group consisting of Sn(O2CR)2, Sn(O2CR)(O2CR′), Sn(O2CR)(O2CR″), and mixtures thereof, where the carboxylate moieties O2CR and O2CR′ independently represent branched carboxylate anions and the carboxylate moiety O2CR″ represents a linear carboxylate anion. Articles comprising the novel compositions are also provided. In addition, methods to improve the thermal stability of polyarylene sulfides, and methods to improve the thermo-oxidative stability of polyarylene sulfides, through the use of the disclosed branched tin(II) carboxylates are provided. The polyarylene sulfide compositions are useful in various applications which require superior thermal resistance, chemical resistance, and electrical insulating properties.
摘要:
A nonwoven web comprising bicomponent fibers. The fibers have continuous phases each of a first polyarylene sulfide (PAS) component and a polymer component. The polymer component may also be a second polyarylene sulfide. The first polyarylene sulfide component contains a tin or a zinc additive or both, and the first polyarylene sulfide component of any given fiber is at least partially exposed to the external surface of that fiber.
摘要:
An improved process for forming polyarylene sulfide fibers is provided. The process comprises forming at least one fiber from a polymer melt comprising a polyarylene sulfide and at least one tin additive comprising a branched tin(II) carboxylate. Using such a melt, the fiber forming continuity is improved compared to that of the native polyarylene sulfide melt processed under the same conditions.
摘要:
This invention relates to methods for decreasing the complex viscosity of a polyarylene sulfide polymer melt while maintaining the molecular weight of the polyarylene sulfide with time. This invention also relates to polymer melt compositions comprising a polyarylene sulfide, wherein the complex viscosity of the composition is decreased relative to the complex viscosity of the native polyarylene sulfide measured under the same conditions, and the weight average molecular weight of the polyarylene sulfide is maintained. The methods of decreasing the complex viscosity of a polyarylene sulfide-containing polymer melt, and the polymer melt compositions so obtained, are useful in processes to produce fibers, films, nonwovens, and molded parts from polyarylene sulfides.
摘要:
A nonwoven web comprising bicomponent fibers. The fibers have continuous phases each of a first polyarylene sulfide (PAS) component and a polymer component. The polymer component may also be a second polyarylene sulfide. The first polyarylene sulfide component contains a tin or a zinc additive or both, and the first polyarylene sulfide component of any given fiber is at least partially exposed to the external surface of that fiber.
摘要:
A method for stabilizing a polymeric structure against thermo-oxidative degradation is described. A polymeric core structure is provided with a skin layer that contains a skin resin in which the skin resin at least partially envelops a portion of the core structure. The skin structure then provides a barrier that thereby stabilizes the portion of the structure that is enveloped. The skin resin is made from a treated polyarylene sulfide.
摘要:
A nonwoven felt for hot gas filtration. The fibers have a polyarylene sulfide (PAS) component that contains a zinc compound. In one embodiment, the PAS comprises at least one zinc(II) salt of an organic carboxylic acid. Also a method for filtering hot gases employing a bag made from a PAS component that contains a zinc or a zinc based additive.
摘要:
This invention provides a multi-layer article comprising a first electrode material, a second electrode material, and a porous separator disposed between and in contact with the first and the second electrode materials, wherein the porous separator comprises a nanoweb consisting essentially of a plurality of nanofibers of a fully aromatic polyimide. Also provided is a method for preparing the multi-layer article, and an electrochemical cell employing the same. A multi-layer article comprising a polyimide nanoweb with enhanced properties is also provided.
摘要:
Insulating materials are provided, the insulating materials comprising a nonwoven web comprising a plurality of continuous spunbonded polyester bicomponent fibers. Each of the plurality of bicomponent fibers comprises a) from about 20% by weight to about 80% by weight of poly(ethylene terephthalate) in a core, and b) from about 80% by weight to about 20% by weight of poly(trimethylene terephathalate) in a sheath surrounding the core, wherein the amounts in percent by weight are based on the total weight of each of the plurality of bicomponent fibers. Also provided are electrical apparatuses comprising the insulating materials and a dielectric fluid, as well as a dielectric material comprising the nonwoven web impregnated with at least 10 weight percent of a dielectric fluid.
摘要:
The invention provides a process comprising heating a polyamic acid fiber to a temperature in the range of a first temperature and a second temperature for a period of time in the range of 5 seconds to 5 minutes to form a polyimide fiber, wherein the first temperature is the imidization temperature of the polyamic acid and the second temperature is the decomposition temperature of the polyimide