Study On Extraction,Dyeing And Light Fastness Of Eupatorium Adenophorum Natural Dyes

Natural dyes are environmentally friendly and have great development prospects in textile ecological dyeing and finishing technology.Eupatorium adenophorum,as one of the major ecological disaster species,posed a serious threat to the ecological environment,economic development and people's life security in China.In this paper,the resource utilization of eupatorium adenophorum was combined with natural dyes.By extracting flavonoids from eupatorium adenophorum,it was used for dyeing wool fabrics,and the feasibility of its use as natural dyes was discussed.Firstly,the extraction and purification methods of flavonoids from eupatorium adenophorum were studied.Ethanol aqueous solution was used to extract flavonoids from eupatorium adenophorum.The effects of ethanol volume fraction,solid-liquid ratio,extraction pH value,extraction time,extraction temperature and extraction times on the extraction effect of flavonoids were investigated.The results showed that the optimal extraction conditions were as follows:ethanol volume fraction 50%,solid-liquid ratio 1:50,extraction pH=8,extraction time 1.5h,extraction temperature 80?,extraction times 1.The flavonoids from eupatorium adenophorum were separated and purified by macroporous resin column chromatography.The macroporous resin was screened and the effects of pH value of sample solution,pH value of eluent,volume fraction of eluent(ethanol),flow rate of sample solution and flow rate of eluent on the separation and purification effect were investigated.The results showed that DM301 macroporous resin was the best for the separation and purification of eupatorium adenophorum natural dyes.The optimal conditions were as follows:pH=6,volume fraction of ethanol of eluent 60%,pH=6,flow rate of loading solution 2BV/h,flow rate of eluent 2BV/h.Then,the structure and properties of the dyes were characterized by fourier transform infrared spectroscopy(FTIR),high performance liquid chromatography(HPLC),liquid-mass spectrometry(LC-MS),and the effects of metal ions,oxidation reductants,acid-base agents,temperature and light on the stability of eupatorium adenophorum natural dyes were investigated.The experimental results show that there are two main flavonoids in the extracted dyes,namely,marigold(C₁₆H₁₂O₈)and quercitrin(C₁₅H₁₀O₈).Eupatorium adenophorum natural dyes could easily react with metal ions to show different colors or precipitate.Eupatorium adenophorum natural dyes had certain stability under weak acid,weak alkali or neutral conditions,but their stability was poor under strong acid and strong alkali conditions.Eupatorium adenophorum natural dyes could not resist oxidation,but they had certain stability against reduction.Light and heat have great influence on the stability of eupatorium adenophorum natural dyes.Further,eupatorium adenophorum natural dyes were used for wool fabrics dyeing,and the effects of dyeing method and mordant type,mordant time,mordant temperature,dyeing pH value,dyeing time,dyeing temperature and dyeing bath ratio on wool fabrics dyeing effect were explored.The experimental results show that the best dyeing method for wool fabrics with eupatorium adenophorum natural dyes was pre-medium method,and aluminum potassium sulfate was used as mordant.The process conditions were as follows:pre-medium time 20min,pre-medium temperature 60?,dyeing pH=5,dyeing time 60min,dyeing temperature 100?,dyeing bath ratio 1:20.The dyeing mechanism of eupatorium adenophorum natural dyes was analyzed.The results showed that the fitting results of dyeing kinetics were in line with the quasi-second-order model and the fitting results of dyeing thermodynamics were in line with the Langmuir model.Finally,the light fastness of wool dyed fabrics with eupatorium adenophorum natural dyes was studied,and the effects of the amount of mordant,the acidity and alkalinity of the fabric surface,the relative humidity of the air,and the liquid rate of the fabric on the fabrics light fastness were investigated.The sun-fading mechanism of eupatorium adenophorum natural dyes wool dyed fabrics was analyzed.The experimental results show that the amount of mordant,the acidity and alkalinity of the fabric surface,the relative humidity of the air and the rate of liquid carry have different degrees of influence on the light fastness of the natural dyed fabrics of eupatorium adenophorum natural dyes.The dyed fabrics of eupatorium adenophorum natural dyes were sun-treated.Under the participation of oxygen and water,the photodegradation products of the dyes were mainly molecular weights of 154(C₇H₆O₄),170(C₇H₆O₅),184(C₈H₈O₅),186(C₇H₆O₆),198(C₈H₆O₆),200(C₈H₈O₆)and other colorless small molecular substances.