| Smart textile is a kind of fiber or fabric which can regulate temperature due to the temperature variation of environment automatically. This kind of fiber or fabric aim at enhancing the comfort of garment, whose principle is that the state of phase change material adhered in fiber or on the surface of fabric makes converse change to release or absorb heat when it is cold or hot, in other words, this textile will release energy to raise temperature inside garment when it is cold, while it will absorb energy to reduce temperature inside garment when it is hot, so it helps the body inside garment to feel good always.At present, the fiber of Outlast is a kind of typical temperature-regulating fiber, the enthalpy of Outlast fiber made of viscose is 10J/g.The fabric of Outlast/silk composed of silk and some Outlast fiber has good property of regulating temperature, but the property will be influenced by pH value and temperature in the process of degumming and dyeing. So, the fabric of Outlast/silk was degummed by protein enzyme in this paper, the optimum process was gotten through some experiments, then the fabric was dyed with reactive dye, moreover, the temperature-regulating property of Outlast/silk was tested before and after the process of degumming and dyeing. It was found that, enzyme degumming was suitable to the fabric of Outlast/silk, the degumming loss percentage got 6.6% after degumming(the degumming loss percentage of silk got 22.8% after the same degumming),the optimum parameters of degumming process were alkali protein enzyme of 4g/L,pH value of 9.5,temperature of 55℃,time of 50min.When the fabric of Outlast/silk was dyed by reactive dyes with one bath dyeing, the dyes of dark red CA, Red A-3G and Blue FN-R had good union color to the fabric. The enthalpy of the fabric of Outlast/silk fell from 5.41J/g down to 5.17J/g after degumming, then it reduced 1.23J/g after dyeing.To solve the above problems, the polyurethane microcapsule was prepared with phase change paraffin as core, the phase change temperature of which is 23.80℃and the enthalpy is 70.31J/g.We studied about the process of core emulsifying, pre-polymer preparation and core microencapsulation, besides, we studied about various properties of the phase change microcapsule, then the phase change microcapsule was applied on the fabric of Outlast/silk by post-treatment. Finally, the fabric of Outlast/silk with the temperature-regulating area of 20～32℃and the enthalpy of 7.71J/g was prepared.It was found in the emulsifying of core that the best emulsifier to paraffin was the composite emulsifier including Peregal O and SDS, the content was 1% and mass ratio was 4:1.In the pre-polymerization, the reaction monomer of PEG had great influence on the property of microcapsule, the phase change microcapsule had smaller particle size and better dispersion when PEG400 was chose as monomer, higher temperature would help the negative reaction in the pre-polymerization, the optimum temperature was 40℃and the reaction time was 3 hours.When the paraffin was wrapped by polyurethane, the kind of chain-extender had great effect on the effective load of microcapsule, the effective load of microcapsule got the biggest value of 45% when 1,4-Butanediol was chose as chain-extender. The ratio between core and shell had great influence on the particle size and productivity of microcapsule, the optimum ratio was 1.5:1,the prepared phase change microcapsule had the particle size of 3.2μm and the productivity of 82% with the above condition. Temperature also had great influence on the productivity, the optimum temperature was 60℃.Reaction time which was confirmed by variation of the content of -NCO was 2 hours. The catalyst of Triethylenediamine helped to enhance the reaction efficiency, the optimum dosage is 1.5%.The particle size of microcapsule got smaller gradually with the increase of stirring rate, the optimum stirring rate was 3500r/min.The polyurethane microcapsule prepared through the above process had the average particle size of 2.78μm, the distribution of which was normal. The structure was proved by FTIR. Both OM and SEM pictures showed that the microcapsule dispersed well in emulsion, and the microcapsule had the structure of core and shell, the surface of which was smooth. The results of DSC showed that the phase change temperature of microcapsule was 23.80℃and the enthalpy of which was 70.31J/g.The result of TG indicated that the phase change microcapsule had good thermal stability, which could resist high temperature of 200℃with no thermal break. The result of cool-heating circulation demonstrated that the shell of microcapsule had good density, the enthalpy of microcapsule had no change after 10 times of cool-heating circulation.When the fabric of Outlast/silk was post-treated by polyurethane microcapsule, the fixing content of finishing agent was related to the enthalpy positively while was related to permeability negatively, taking both the two factors above into account, the fixing content was chose at 13g/m~2.The curing temperature and time had great influence on the washing durability of fabric, the optimum curing temperature was 120℃and the optimum curing time was 100 seconds. After post-treatment, the phase change temperature of the fabric of Outlast/silk rised from 21.39℃to 24.05℃, and the enthalpy of which rises from 3.94 J/g to 7.71J/g.SEM pictures of the fabrics before and after treatment showed that the phase change microcapsule had been fixed on the surface of fabric evenly. The prepared fabric of Outlast/silk has good property of temperature regulation which was confirmed through temperature-rising curves.
|
PDF Full Text Request