Preparation method of spandex with reactive dye easy-dying function

Abstract

The invention relates to a preparation method of spandex with a reactive dye easy-dying function. The method comprises steps as follows: 1), a modifying auxiliary is added to N,N-DMAC (dimethylacetamide), and the mixture is stirred to form a stable solution; (2), DMAC and PTMG (polytetramethylene ether glycol) are sequentially added to a prepolymerization tank, 4,4-MDI (diphenyl-methane-diisocyanate) is added according to the set proportion of NCO / OH, and sufficient prepolymerization is performed; (3), a prepolymerized product is transferred to a chain extension tank, a mixed amine solution is used for performing chain extension and chain termination reactions on the prepolymerized product, and a polyurethane urea solution is obtained; (4), a modifying auxiliary / DMAC solution is added to the prepared polyurethane urea solution, and the mixture is transferred to a stock solution storage tank after the complete reaction; (5), an antioxidant, a lubricating agent, an ultraviolet absorbent and the like are added to the polyurethane urea solution, and the mixture is stirred for dispersion; (6), a dry spinning system is used for drawing and drying of a spinning solution, and the spandex with the reactive dye easy-dying function is obtained through the further reaction of polymer with excessive modifying auxiliaries in a channel.

Description

technical field [0001] The invention relates to a method for preparing spandex easily dyeable with reactive dyes, and belongs to the technical field of polyurethane elastic fiber material manufacturing. Background technique [0002] Polyurethane elastic fiber, commonly known as spandex, is a block copolymer containing repeated urethane groups (-NH-C(=O)-O-) segments in the main chain. It has excellent resilience and dimensional stability, and it can be blended with non-elastic fibers to obtain fabrics, which can greatly improve the wearing comfort of fabrics. However, there are still some problems in the production and application of spandex, which may affect the further application of spandex. From the perspective of spandex products, cotton / spandex interwoven knitted fabrics, viscose / spandex fabrics and other products account for a large part of the application, and the unsatisfactory dyeing effect is more prominent. Since the composite textiles of spandex and cellulose ...

AI Technical Summary

Problems solved by technology

Since the composite textiles of spandex and cellulose fibers generally require reactive dyes to be dyed at 100°C, and spandex molecules lack groups that react with reactive dyes, it is difficult for reactive dyes to form covalent bonds with it. Low reactivity, so the dyeing rate is very low, resulting in uneven dyeing of the cloth surface

At the same time, some of the dyes dyed on the spandex fiber will fall off again when adding alkali to fix the color, and the spandex fiber will also be damaged in the alkaline environment.

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