Research Of Hydrophilic Modification By UV/Nano-TiO₂ And Graft Milk Protein On PET Fabric

Polyester is widely used for textile fabric and fiber product of other industry because of its good crease elasticity and crispness. Because PET macromolecular only has two hydroxyls at both ends, so its fabric is hydrophobic, on-hygroscopic, no moisture conductivity, poor wearing comfort and poor biocompatibility. It is always a hot task about hydrophilic modification of PET fabric. At present, surface hydrophilic modification methods of Polyester fiber mainly include plasma method, alkali peeling method, graft copolymerization method, ultraviolet irradiation method, etc. Moreover, protein is good close to skin and water absorption. If grafting protein to PET fabric, which could improve the PET fabric to good close skin and enhance its wearing comfort and biocompatibility.In this dissertation, in order to improve the efficiency and lower the energy consumption of ultraviolet irradiation modified PET fabric, so take nano-TiO2 into the process of ultraviolet irradiation modified PET fabric; take H2O2 into the process of UV-nano-TiO2 modified PET fabric to realize one step to obtain super-hydrophilic modification and colored PET fabric; graft milk protein to PET fabric with good cross linking and soft function of sucrose glyecidyl ether, view to obtain good wearing comfort and biocompatibility of high functioning PET fabric; Dye PET fabric modified by UV-nano-TiO2 with disperse dye, and research the effect of UV-nano-TiO2 modification to leveling, dyeing property and color fastness of PET fabric. SEM confirmed PET Fiber surface morphology; FTIR and XPS analyzed the generation of functional group on fiber surface; XRD analyzed the crystallinity of modified PET fabric; DSC and TG analyzed thermal stability of modified PET fabric; hydrophilic, whiteness, crease elasticity, break strength, stiffness and color fastness had been tested. Results of research show:(1) Taking nano-TiO2 into the process of ultraviolet irradiation modified PET fabric, which sharply improved the efficiency, shortened the time, and lowered the energy consumption; Super-hydrophilic PET fabric were modified 60min by UV- nano-TiO2, water contact angle was 0°, water drop disappeared time was 5.6s, water absorption was 123.55%, capillary rise height was 109.9mm, spray rating was level one. SEM showed a layer of material covering on fiber surface; FTIR indicated fiber surface was oxidized to generate a new kind oxide which containing -OH and -COOH. Also, degree of crystallinity decreased a little; thermal stability and crease elasticity increased a little; meanwhile whiteness, break strength and stiffness kept well.(2) Taking H2O2 into the process of UV-nano-TiO2 modified PET fabric, which made the integration process of super-hydrophilic modification and fabric colored by itself come true and obtained the super-hydrophilic and colored yellow-green of PET fabric. Range analysis of K/S value in three factors and four levels orthogonal experiment showed that the order of affect factors on colored was UV irradiating time, concentration of H2O2, concentration of nano-TiO2. Best process parameters were as follows:UV irradiating time 80min,4.0% H2O2,3.0% nano-TiO2. The maximum K/S value reached 2.7179, and hue angle was 107.00°. SEM, XPS and FTIR showed that modified PET fiber had generated a new kind oxide which concluding -NO,-NO2,-OH, >C=O, and aromas of conjugate structure. Degree of crystallinity and thermal stability increased a little. PET fabric modified by UV- nano-TiO2/H2O2 had a good coloration leveling property. Crocking fastness and soaping fastness all kept at level of 4-5. Break strength decreased a little and crease elasticity increased.(3) Grafting milk protein to PET fabric modified 60min by UV- nano-Ti02 at high temperature with sucrose-glyecidyl-ether, which helped the PET fabric obtain good wearing comfort and biocompatibility of high functioning. Grafted milk protein of modified PET fabric had a good washing fastness, and its residual percentage after hot-water washing was 97.60%. SEM and FTIR showed milk protein had been grafted on fiber surface. Degree of crystallinity, water vapour transmission rate and air penetrability decreased a little. Thermal stability, water absorption and moisture regain increased a little. Crease elasticity kept well. Stiffness increased.(4) Comparative analysis of Dyeing PET fabric and PET fabric modified 60min by UV- nano-TiO2 with disperse red 3B, disperse blue 2BLNG-L, disperse yellow SE/RGFL, disperse grass green GL. Leveling property of Modified PET fabric kept well, and dyeing property improved a little. Crocking fastness and soaping fastness of PET fabric and modified PET fabric all kept above level 4.