Study On The Testing Method Of The Component Content Of Cotton/Spandex Blended Fabrics

Cotton/Spandex fabrics as one kind of common textiles, account for a large proportion in thecomponent content testing work of textiles.The current national standard has provided threetesting methods, including artificial hand split method, dimethylformamide dissolving method anddimethylacetamide dissolving method, but they all have some limitations, the detection efficiencyis too low or the result is not accurate. It’s immediately to get a new testing method which will befast, accurate and scientific in the component content analysis work of cotton/spandex fabrics.This project used hydrochloride acid to testing cotton/spandex fabrics, studied the factors and lawsaffect the testing result by using hydrochloric acid and also optimized the experimental conditions,according to the characteristics of the practical application. The results of this study aimed toprovide a reference method during the quantitative analysis work of textiles.In order to measure each fiber quality percentage of cotton/spandex fabrics, the study tried todissolve cotton completely under appropriate concentration of hydrochloric acid, but left spandexunaffected. So, firstly, the project studied the dissolved law of cotton and spandex when they weresoaked in hydrochloride acid. By orthogonal experiment and single factor test, the study screenedout the experimental conditions that would dissolving cotton totally but has no effect on spandex，including the concentration of hydrochloric acid, reaction temperature and reaction time.Secondly, on the basis of the above research, the study conducted the actual testing fordifferent cotton/spandex fabrics by hydrochloric acid under certain conditions.Testing resultsshowed that the quantitative analysis of cotton hydrochloric acid is feasible and the accuracy ofthe results is qualified. To seek a better testing condition, the project made a further study about the concentration of hydrochloric acid and got the suitable conditions lastly, and also developed areference standard about the quantitative analysis work of cotton/spandex fabrics by using thismethod.To save time in testing heavy-type of cotton/spandex fabrics, the study introduced ultrasonictreatment and sodium hypochlorite pretreatment methods during the process of hydrochloric acidtesting method, and has researched the effects of processing time and reagent concentration to thetesting results. Fortunately, these two methods got accuracy testing data while greatly reducing thewhole testing time, also made a reference to the analysis work of heavy-type cotton/spandexfabrics.Finally, the study assessed the uncertainty evaluation for cotton/spandex fabrics and analyzedthe main sources of uncertainty by hydrochloric acid testing method, offered proposal forlaboratory testing work.