Preparation And Properties Of Polyamide Parallel Composite Fibers

Parallel composite fibers are a type of bicomponent fiber prepared by arranging two polymers with different structures and properties in a parallel manner.Due to the difference in thermal shrinkage performance between the two components,the parallel composite fibers have a three-dimensional spiral winding structure similar to a spring,which gives the fibers excellent elasticity after processing.Therefore,parallel composite fibers are widely used in elastic fabric related products.Due to the cost and processing advantages of polyester,the components used in the research on parallel composite fibers are mainly concentrated on polyester materials such as PET(Polyethylene Terephthalate)and PTT(Polytrimethylene Terephtalate).In recent years,with the localization of raw materials for polyamide production,the production cost of polyamide has gradually decreased,and polyamide fibers have developed rapidly.Compared to polyester fibers,polyamide fibers have better skin friendly comfort.The preparation of parallel composite fibers using polyamide materials not only utilizes the advantages of the material itself,but also utilizes the elasticity brought by the fiber curl structure,which has broad application prospects and provides more choices for the development of elastic fibers.This article selects several different viscosities of polyamide 6(PA6),polyamide 66(PA66),and polyamide elastomer as parallel composite spinning raw materials,and designs polyamide based parallel composite fibers.Firstly,the thermal properties,crystallization properties,and rheological properties of several polyamide based raw materials were tested,and the spinnability of the raw materials was explored to clarify the suitable range of spinning processes for different raw materials.A series of polyamide based parallel composite fibers were prepared by screening the raw material system and optimizing the spinning process parameters.The mechanical,moisture absorption,curling,and elastic properties of the prepared parallel composite fibers was systematically compared with commercial polyester based parallel composite fibers(represented by Du Pont’s T400).The results show that polyamide based parallel composite fibers have better moisture absorption and thermal stability properties than T400 fibers,Parallel fibers spun from polyamide elastomer and PA6 do not require heat treatment to form a curl structure,and their curl and elastic recovery properties are also better than T400 fibers.Finally,the fabric properties of polyester based and polyamide based composite fibers were tested.The results indicate that polyamide based fiber fabrics exhibit better breathability and moisture permeability.