Preparation Of Jasmine Microcapsules And Research Of Its Application On Cotton Fabrics

Nowadays, developing new products with high added-value properties is very imperative for the textile industry. Encapsulation techniques allow an opportunity for the application of some functional agents on fabrics, such as insect repellents, anti-cellulite treatments, long-lasting fragrances, skin softeners and some medical applications such as antibiotics, hormones and other drugs. This innovative technology makes use of microcapsules which act as small containers of liquids to be released from the inner core under controlled conditions to address a specific purpose. The microcapsules can be applied on textiles by printing, exhaustion dyeing, impregnation and coating. A binder agent is required for the combination of microcapsules in the fabrics, its function is to fix the microcapsules in the fabric to improve the durability.According to some researches released recently, jasmine scent, like tranquilizer is helpful to the alleviation of insomnia, anxiety and fidget. The traditional medicines can give rise to addicting and even lead to some side-effects despite of its effectiveness in curing, however jasmine scent doesn't have such drawbacks.In this paper, a control-release jasmine microcapsules were synthesized using melamine resin and jasmine essential oils by in-situ polymeriztion. Fragrant fabrics with good durabilities were prepared using thermal curable binders and UV curable binders respectively. The whole study was composed of three parts:(1) In the preparation of jasmine microcapsules, effect of ratio of core and shell ratio and droping rate of melamine resin prepolymers on the microcapsules morphology and thermal stabilities, methods of reducing the remnant free formaldehyde were carried out. An appropriate preparation method of preparation of jasmine microcapsules was established. (2) using polyurethane binder and acrylic binder to prepare fragrant cotton fabrics. The effect of different kinds of binders and different thermal curing conditions on the washing durability were discussed. A fit finishing method was established and physical properties and abrasion test were conducted. (3) using water-based UV curable binder to fix microcapsules on cotton fabrics. Effects of finishing method, photoinitiators, UV light lamps, curing time on the washing durability of fragrant fabrics were investigated. A premium finishing method was also established and physical properties were tested. The structure of the microcapsules and fragrant fabrics were characterized by the FTIR and ATR-FTIR, the morphology characteristics of the microcapsules and fragrant fabrics were observed by means of optical microscopy and SEM,the particle size and size distribution of the microcapsules were measured by the laser particle analyzer. Odor evaluation was carried out by human olfactory sensations and ultraviolet absorption spectrophotometry. The main results were summarized as follows:(1) FTIR spectra of jasmine oil, melamine resin, jasmine microcapsules showed that jasmine oil had been microencapsulated by melamine resin. Under certain dropping rates of melamine resin prepolymer, reducing the ratio of core and shell helps to increase the thermal stability of microcapsules, however worsen the morphology the microcapsules. Slowing down the ratio of core and shell can help to improve the morphology while maintaining good thermal stability. After the reaction, hydrogen peroxide, urea, ammonium persulfate can be used to eliminate the remnant free formaldehyde, and urea seems to be the most suitable one. The optimum conditions for jasmine microcapsule preparation were defined as 1:1 ratio of core and shell, dropping rate of melamine resin prepolymer 0.6mL/min, and urea as anti-formaldehyde agent.(2) By using thermal curable binders, the jasmine microcapsules were fixed onto the cotton fabric by dipping padding method. The results showed that polyurethane binder can make fragrant fabric endure 5 washing cycles, acrylic binder can make fragrant fabric bear 15 washing cycles. The stronger the curing condition, the higher the washing durability of finished samples. The optimum curing condition for polyurethane and acrylic binder were 150℃for 2min and 160℃for 2min respectively. The finished fabrics could bear over 6,000 abrasion cycles and the physical properties didn't change significantly. Acrylic binder treated fragrant fabric had higher breaking strength and stiffness than polyurethane binder, while polyurethane binder treated fragrant fabric had a higher white index than acrylic binder. The free formaldehyde content could reach the underwear standard.(3) By using UV curable binder, jasmine microcapsules were novelly applied on the cotton fabric. The results showed that finishing method, photoinitiator and UV light lamp can have great influence on the washing durability of the fragrant fabric. When using coating method,20g/kg Runtecure1265 as photoinitiator,1000W electrode high pressure mercury arc continuous UV light as UV light source, curing for 4min, the fragrant fabric could bear 30 washing cycles. The breaking strength and stiffness of the finished fabric increased about 3.7% and 40.7% respectively, white index reduced to 42. Free formaldehyde content met the underwear standard.