Fabrication and Basic Properties of Elastomeric Staple Fiber Based on Poly(Butylene Terephthalate)-Block-(Tetramethylene Oxide) by Melt Spinning

Abstract

Melt spinning of special chips of poly(butylene terephthalate)-block-(tetramethylene oxide) was studied.The obtained fiber possesses rubber-like elasticity at room temperature. The basic properties of this elastomer fiber are fineness 1.7 dtex, tensile strength 3.35 cN/dtex, breaking extension 68%, and elastic recovery >95% at 15% elongation. A new type of elastomer staple fiber of this block-copolymer is successfully fabricated by a traditional production line for melt spinning.Elastomeric fibers are mainly distinguished by very high extension and elastic recovery. Such fibers were previously prepared from natural rubber and synthetic elastomers of the block-copolymer type [1, 2]. Then, elastomeric fibers based on polyurethane known as Spandex, Lycra, elastane, etc. appeared and were used by various manufacturers to create many types of textiles [3]. Recently, the production of new block-copoly(ether ester) fibers and polyolefin elastomeric fibers was reported to be in the initial development stage on the industrial scale [4][5][6][7].Block-copolymers containing alternating blocks of polyether and polyester are a new type of polymeric elastomer. Their synthesis, structure, and properties were systematically described in a monograph by Fakirov [6]. Their application as plastics and elastomers has a long history. Their chemical structure appears in Appendix 1.Various block-copoly(ether ester)s with various melting points, viscosities, elongations, elasticity moduli, and recoveries can be easily obtained by changing the weight or molar ratio of hard and soft segments.Research on melt spinning of block-copoly(ether ester)s is being conducted in several laboratories. The obtained elastomeric fibers demonstrate various levels of elastic properties. Copoly(ether ester) fibers with high contents of soft segments show the greatest elasticity; with low contents of soft segments, the lowest. The former has strength like Lycra; the latter, ordinary PET fiber.The synthesis of block-copoly(ether ester) elastomers [9]; their structural characteristics [10]; and rheological [11], mechanical [12,13], fiber-forming [14], and surface properties [15] were systematically studied in the laboratory of one of us (D. Wu). The resulting know-how was transferred to Chengdu Jilun Co., which now produces different chips of poly(ether ester)s and filaments based on them. Such elastomeric fibers are usually used only as filaments (monofilament or multifilament yarns) to manufacture various textiles.Although a staple fiber of a block-copoly(ether ester) was manufactured by a Japanese company under the trademark Rexe, detailed information about its production by melt spinning could not be found in the open literature. However, reasoning logically, if high-quality elastomeric staple fibers can be produced, then other new textile products can also be produced.The goal of the present work was to use traditional melt spinning to manufacture staple fiber with high rubberlike elasticity that could be processed into yarn on traditional textile units, ...

Untitled

“…Many papers, for examples [2,3] have been published on the manufacture of filaments on a laboratory scale, but few have been published on the manufacture of staple fibers from them. The only exception was the author's own recent article [4].…”