The present application discloses a polyamide 5X fiber, wherein raw materials for producing the polyamide 5X fiber comprise at least 1,5-pentane diamine and a long carbon chain diacid; or comprises a polyamide 5X obtained by the polymerization of 1,5-pentane diamine and a long carbon chain diacid as monomers. The 1,5-pentane diamine or the long carbon chain diacid are produced from bio-based raw materials by a fermentation process or an enzymatic conversion process; and the long carbon chain diacid is at least one of C6-20 aliphatic long carbon chain diacids. The long carbon chain diacid is at least one of C6-20 aliphatic long carbon chain diacids. The polyamide 5X fiber includes pre-oriented yarns, drawn textured yarns, fully drawn yarns, staple fibers, industrial yarns, continuous bulked filaments and monofilaments, preferably pre-oriented yarns, drawn textured yarns and/or fully drawn yarns. The raw materials used for producing the polyamide 5X resin are prepared by biological processes, and are green materials. The polyamide 5X fiber has good mechanical properties, dimensional stability, softness, quick-drying performance and dyeing properties.

The present application discloses a polyamide 5X fiber, wherein raw materials for producing the polyamide 5X fiber comprise at least 1,5-pentane diamine and a long carbon chain diacid; or comprises a polyamide 5X obtained by the polymerization of 1,5-pentane diamine and a long carbon chain diacid as monomers. The 1,5-pentane diamine or the long carbon chain diacid are produced from bio-based raw materials by a fermentation process or an enzymatic conversion process; and the long carbon chain diacid is at least one of C6-20 aliphatic long carbon chain diacids. The long carbon chain diacid is at least one of C6-20 aliphatic long carbon chain diacids. The polyamide 5X fiber includes pre-oriented yarns, drawn textured yarns, fully drawn yarns, staple fibers, industrial yarns, continuous bulked filaments and monofilaments, preferably pre-oriented yarns, drawn textured yarns and/or fully drawn yarns. The raw materials used for producing the polyamide 5X resin are prepared by biological processes, and are green materials. The polyamide 5X fiber has good mechanical properties, dimensional stability, softness, quick-drying performance and dyeing properties.

A recycled polyester filament and preparation method therefor are disclosed. In the process of preparing a fiber from a recycled polyester according to the FDY process, the ring-blowing is used for cooling, and the distribution of spinneret holes on the spinneret is controlled to meet certain conditions, then the recycled polyester filament is obtained by relaxation heat treatment after a fully drawn yarn is produced. The spinneret holes are C-shaped spinneret holes and circular spinneret holes, the cross-section of the C-shaped spinneret hole is composed of an outer arc, an inner arc, and two line segments, and two endpoints of the outer arc are A and B respectively; wherein the certain conditions include: all the spinneret holes are distributed in concentric circles, and the C-shaped spinneret holes are located on the outermost circle, rotating at different angles and randomly distributed.

A recycled polyester filament and preparation method therefor are disclosed. In the process of preparing a fiber from a recycled polyester according to the FDY process, the ring-blowing is used for cooling, and the distribution of spinneret holes on the spinneret is controlled to meet certain conditions, then the recycled polyester filament is obtained by relaxation heat treatment after a fully drawn yarn is produced. The spinneret holes are C-shaped spinneret holes and circular spinneret holes, the cross-section of the C-shaped spinneret hole is composed of an outer arc, an inner arc, and two line segments, and two endpoints of the outer arc are A and B respectively; wherein the certain conditions include: all the spinneret holes are distributed in concentric circles, and the C-shaped spinneret holes are located on the outermost circle, rotating at different angles and randomly distributed.

The present disclosure provides a polyamide 5X staple fiber, a preparation method and use thereof. The polyamide 5X staple fiber has a denier of 8.0-30.0D, a breaking strength of 2.0-6.0 cN/dtex, and an elongation at break of 30-100%. The polyamide 5X staple fiber has good mechanical properties and softness, and a blended wool yarn for manufacturing carpets with good mechanical properties, dyeability, and wear resistance can be obtained by using the polyamide 5X staple fiber.

The present disclosure provides a polyamide 5X staple fiber, a preparation method and use thereof. The polyamide 5X staple fiber has a denier of 8.0-30.0D, a breaking strength of 2.0-6.0 cN/dtex, and an elongation at break of 30-100%. The polyamide 5X staple fiber has good mechanical properties and softness, and a blended wool yarn for manufacturing carpets with good mechanical properties, dyeability, and wear resistance can be obtained by using the polyamide 5X staple fiber.

A weldable spun-bonded nonwoven has endless filaments of a thermoplastic plastic that contain at least 3 wt % of at least one filler to improve the weldability of the spun-bonded nonwoven. In addition the endless filaments are monocomponent filaments.

A weldable spun-bonded nonwoven has endless filaments of a thermoplastic plastic that contain at least 3 wt % of at least one filler to improve the weldability of the spun-bonded nonwoven. In addition the endless filaments are monocomponent filaments.

The method for producing non-core beta silicon carbide fibers includes four steps. The first step is spinning of multifilament polymeric fiber by melt-extrusion of polycarbosilane. The second step is thermooxidative cross-linking for which the produced spun polymeric fibers are cured in an oxidation furnace at a temperature of 175-250 degrees C. at a heating rate of 3-10 degrees C./h until their weight is increased by 6-15%. The third step is carbonization of the produced cured polymeric fibers with the conversion into the ceramic phase. The fourth step is finishing of the produced beta silicon carbide fiber. The effect of the invention is producing non-core silicon carbide fibers, improving their strength performance, improving resistance to high temperatures and their high creep resistance, stable fiber properties, optimal average diameter of fibers, absence of foreign impurities in the fiber composition.

The method for producing non-core beta silicon carbide fibers includes four steps. The first step is spinning of multifilament polymeric fiber by melt-extrusion of polycarbosilane. The second step is thermooxidative cross-linking for which the produced spun polymeric fibers are cured in an oxidation furnace at a temperature of 175-250 degrees C. at a heating rate of 3-10 degrees C./h until their weight is increased by 6-15%. The third step is carbonization of the produced cured polymeric fibers with the conversion into the ceramic phase. The fourth step is finishing of the produced beta silicon carbide fiber. The effect of the invention is producing non-core silicon carbide fibers, improving their strength performance, improving resistance to high temperatures and their high creep resistance, stable fiber properties, optimal average diameter of fibers, absence of foreign impurities in the fiber composition.