Effect Of Peppermint Oil Microcapsule Finishing On The Comfortable And Cool Functionalization Of Polyester Fabric

Polyester fiber has become the most widely used synthetic fiber because of its low production cost,good mechanical properties and anti-insect,however lack of hydrophilic groups in the polyester macromolecules deteriorates the hygroscopicity of polyester fabric and tends to make the human body feel stuffy.So this article mainly aims at the comfort and cool functionalization of polyester fabric.With the increasing application of microcapsule technology in the textile,microcapsule finishing can be applied to modification of polyester fabrics.Peppermint oil which is often used in food and hygiene products for its excellent cooling and health properties can be made as microcapsules to improve the comfortability and coolness of polyester fabric by padding process.Effects of peppermint oil microcapsule finishing can be studied through researches of changes between the polyester fabric before and after finishing.The microcapsules were prepared by complex coacervation method which wall-materials were gelatin and sodium alginate and core material was peppermint oil.The preparation process of microcapsules was optimized by single factor test and the best preparation technology was as follows:pH value was 4.3,wall material ratio GE:SA=4:1（m:m）,concentration of emulsifier was 0.5%（v/v）,emulsification time was 9 min,core wall ratio 1:1(v_{peppermint oil}:m_{wall material}=1:1),wall-material concentration was 1.75%（m/v）,stirring speed was 600 rpm.The results of polarized light microscopy,SEM and FTIR showed that morphology of the microcapsules were regular and completely spherical which diameter was20⁵0μm.The microcapsule yield,payload and wall-material utilization rate were 85.64%,50.00%and 78.75%,respectively.Thermogravimetric tests showed that the microcapsules could maintain certain thermal stability below 250℃and controlled the slow release of peppermint oil.Polyacrylic acid was blended with a suspension of peppermint oil microcapsules as finishing agent for the modification of polyester fabric by padding finishing.The optimum process parameters was as follows:the binder（polyacrylic acid）concentration is 0.5%,the microcapsule concentration was 50%,the prebaking process was 80℃,3 min,and the baking process was 120℃,3 min.The finished polyester fabric had a weight gain rate of 1.34%and it could be increased to 1.50%and 1.53%if the alkali pretreatment and plasma pretreatment were added before microcapsule finishing.The results of SEM and FTIR on the fabric showed that microcapsules had been successfully finished into the fabric and made polar groups connected to the fabric.Through testing the relevant properties of fabrics before and after finishing,the results showed that peppermint oil microcapsule could significantly improve the comfortability and coolness of polyester fabric,and pretreatmenst could further improve the modification effect.Plasma pretreatment could further increase the moisture permeability,warp and weft wicking height,evaporation rate and cool feeling coefficient of the fabric to 4.66%,52.7%,42.9%,48.15.%and 8.63%respectively,the drip diffusion time was reduced from 121.6 s to less than1 s,while alkali pretreatment was more conducive to the improvement of air permeability and water absorption rate which were increased by 49.25%and 17.1%respectively.Besides,overall moisture management capability was increased from 0.5418 to above 0.72,and the pretreatments could further improve the the moisture management ability.The results of whiteness showed that the microcapsule finishing would reduce the whiteness by 17.50%and alkali pretreatment and plasma pretreatment made the whiteness further reduced by 24.82%and 30.15%.The results of breaking strength showed that microcapsule finishing had little effect on the wearability of the fabric and the strength loss rate was within 13%.As for laundering durability,the two pretreatments could significantly improve laundering durability of finished polyester fabric,especially the plasma pretreatment could reduce the weight loss rate of the fabric after washing 5 times from 60.61%to 38.41%,the weight loss rate after washing 25 times from 90.15%to 55.62%.In addition,the results of the comprehensive handle indicated that microcapsule finishing would deteriorate the fabric’s hand feeling,and the plasma pretreatment would aggravate the deterioration,while the alkali pretreatment had a positive effect on hand feeling by improving the softness and smoothness of fabric.Microcapsule finishing had little effect on the physical and mechanical properties of polyester fabric,which breaking strength loss rate was within 4%and whiteness loss rate was within 20%.The hand feeling was reduced by microcapsule finishing,but alkali pretreatment was good for improving the softness and smoothness of the fabric.The polyester fabric would be adhered the microcapsule finishing agent after finishing,and the loss rate of the finishing agent was 60.61%after washing 5 times,and when washing 25 times it would reach 90.15%.Plasma pretreatment could obviously improve the laundering durability,which made the loss rate reduce to 38.41%after washing 5 times and to 55.62%after washing 25 times.