The Effect Of Supercritical CO₂ Anhydrous Dyeing On The Structure And Wearability Of Polyester Filament And Its Fabric

In the textile industry,the dyeing medium of traditional polyester fiber dyeing technology is mostly water.In the dyeing and finishing process,a large amount of dispersant and other dyeing aids are used.The process is long and requires a lot of water resources and energy.At present,China's annual output of polyester fiber accounts for more than 70% of the world's total output of polyester fiber,reaching an annual output of 40 million tons.Therefore,solving the problem of polyester fiber printing and dyeing wastewater plays an important role in solving the wastewater discharge of the entire printing and dyeing industry.Therefore,it is the development direction of the entire printing and dyeing industry to develop clean and environmentally friendly dyeing and finishing processing technologies and explore anhydrous or less water dyeing processes.Supercritical carbon dioxide fluid dyeing waterless technology is a new type of anhydrous dyeing technology that uses supercritical carbon dioxide fluid instead of water as the dyeing medium.The dyeing time of supercritical carbon dioxide fluid anhydrous dyeing technology is 3-6 times faster than traditional water dyeing,and the entire processing time can be shortened by 1-2 hours.After the dyeing is completed,the supercritical carbon dioxide fluid is cooled and depressurized,and the dye dissolved in the supercritical carbon dioxide fluid in the undyed fabric is precipitated in powder form,and the recovered dye and CO₂ gas can be used again.Supercritical CO₂ fluid anhydrous dyeing technology fully embodies the concept of green environmental protection,meets the needs of national ecological civilization construction,and is a promising dyeing technology.Carrying out research in this field is of great significance for the dyeing and finishing industry to say goodbye to its dependence on water and to maintain the sustainable development of the industry.However,the effect of supercritical CO₂ anhydrous dyeing on the physical and chemical mechanical properties of polyester fibers is not clear.There are questions about the performance of fabrics woven with supercritical CO₂ anhydrous dyed polyester fibers,which greatly limits the technology.Promotion and its application.In order to clarify the effect of supercritical CO₂ anhydrous dyeing on the physical and chemical mechanical properties of polyester filament,in order to provide a basis for the development of polyester supercritical CO₂ anhydrous dyeing products,this article uses DSC,SEM,X-ray diffraction,infrared spectrometer,sound velocity orientation measurement Instrument,electronic single yarn strength machine,capillary effect tester and other methods,the surface morphology,molecular structure,crystallinity,orientation and wicking performance of supercritical CO₂ fluid anhydrous dyed polyester package yarn and traditional water-dyed polyester yarn And tensile properties were compared.DSC and X-ray diffraction test results show that when dyeing with the same dye,the polyester filament dyed and processed with supercritical CO₂ anhydrous cheese yarn has no change in crystal structure and that of the traditional water-dyed polyester filament;anhydrous dyeing The polyester filaments and thermodynamic properties are basically the same as the traditionalwater-dyed polyester filaments,but the crystallinity is slightly reduced.The crystallinity of the filament sample is decreased by about 2.39%,and the crystallinity of the fabric sample is decreased by about 1.5%.Fourier infrared spectroscopy tests showed that the main functional groups of each style did not change,and the microstructure of the style did not change.The SEM image shows that the supercritical CO₂ anhydrous dyeing further causes the oligomers in the polyester filament to migrate to the surface,but the fiber surface does not show wrinkles and no obvious scratches.The test results of electronic single yarn strength machine and capillary effect tester show that when the same dye is used for dyeing,the breaking strength and breaking elongation of polyester filament yarn dyed with supercritical CO₂ anhydrous package yarn are basically the same as traditional water-dyed polyester filament yarn.Consistent,but the CV value of polyester filaments dyed and processed with supercritical CO₂ anhydrous package yarn is reduced by 8.7%,and the wicking performance is reduced by about 80% compared with traditional water-dyed polyester filaments.Supercritical CO₂ anhydrous dyeing The oligomers in the polyester filaments further migrated to the surface,but no creases appeared on the fiber surface and no obvious scars.In general,although the supercritical CO₂ anhydrous package yarn dyed polyester filament is different from the traditional water-dyed polyester filament,it can fully meet the requirements of consumption.This article also discusses the effect of supercritical carbon dioxide fluid anhydrous dyeing technology on the wearability of polyester filament fabrics.Use traditional water-dyed polyester filaments and supercritical carbon dioxide fluid anhydrous dyed polyester filaments to make knitted fabrics of the same specifications,using digital air permeability meter,digital fabric thickness meter,electronic fabric strength meter,flat-type insulation meter,etc.Means,comparatively studied the air permeability,thickness and weight,burst strength and heat retention of the two fabrics,and tested the fabric style of the two fabrics using the KES style evaluation system.The analysis shows that under the same weaving conditions,the performance of supercritical CO₂ anhydrous dyeing polyester filament fabrics is basically the same as the wet perspiration ability of traditional water-dyed polyester filament fabrics,and the breathability is slightly better than traditional water-dyed polyester fabrics;The thickness of polyester filament fabrics processed by supercritical CO₂ anhydrous dyeing is reduced by 1.57% and the weight is reduced by 1.68%;the heat transfer coefficient is reduced by about 22.13%,the insulation rate is increased by about23.96%,and the Kro value is increased by about 28.87%;The polyester filament fabric processed by anhydrous dyeing has a more stiff style,a slightly rough feel,and a surface roughness increase of 5%.Knitted fabrics of polyester filaments dyed with supercritical carbon dioxide fluid without water have reached the national level 4standard in light fastness,soap fastness,perspiration fastness and rubbing fastness,reaching the national textile basic The safety technical specifications for the traditional water-dyed polyester fabric can fully meet the requirements for use and can be used in the clothing industry.