Synthesis And Application Of Waterborne Polyurethane Fixing Agent

Reactive dyes are widely used to various fabrics for its properties such as beautiful color,wild chromatogram and low production cost.The dyed fabric showed good fastness when dyeing light-colored fabrics,but various reactive dyes have poor wet rubbing fastness when dyeing dark fabrics.One way to solve this problem is to use fixing agent.Although the conventional fixing agent Y can effectively improve the fastness of the fabric,it is harmful to the human body with formaldehyde.At present,the types of aldehyde-free fixing agents commonly used mainly include polyamine polymers and cationic polymers.Polyamine polymer fixing agents have good effects,but it is easy to cause color change;the fixation effect of polycation fixing agents are good,but the diallylamine of raw material is difficult to purchase due to environmental regulations.Based on this,two kinds of waterborne polyurethane fixing agents were studied,one was reactive waterborne polyurethane fixing agent,another was silicone modified waterborne polyurethane fixing agent,and they were prepared and used for fixing to reactive dyes.The research contents and result are as follows:(1)The cationic chain extender(EGDEA)was firstly synthesized using ethylene glycol diglycidyl ether(GDE)and diethylamine(DEA)as raw materials.Then,the reactive waterborne polyurethane fixing agent(ACPU)was successfully synthesized via step-by-step polymerization with isophorone diisocyanate(IPDI)and polypropylene glycol(PPG-1000)as the monomers,EGDEA as the hydrophilic monomer,Methyl ethyl ketone oxime(MEKO)as the blocking agent,acetic acid as the neutralizer.The chemical structure of the material and the product were characterized by Fourier transform infrared spectroscopy(FTIR)and canbon-13 nuclear magnetic resonance spectroscopy(13C NMR).The main physical properties of the emulsion were determined and the synthesis process was optimized.The optimal synthetic conditions of ACPU were as follows:R value(molar ratio of NCO to OH)is 2.0,the weight of EGDEA was 6%(as a percentage of the total mass of the reaction monomer),neutralization degree was 100%,the blocking temperature was 45 C,the blocking time was 100 min.The ACPU was applied to the fixation of cotton fabrics with reactive dyes.Finally,compared with the dyed cotton fabric without fixation,the dry rubbing fastness of the dyed cotton fabric treated by ACPU can be improved by 0 or 0.5 grades,the wet rubbing fastness can be improved by 0.5 or 1 grades,and the soaping fastness can be improved by 0 or 0.5 grades,which has less influence on the fabric shade.However,it has a certain influence on the softness of the fabric,when the concentration of ACPU was 4%(owf),the baking temperature and time were 160 C and 120 s,respectively.(2)The polyether silicone oil(HS)was synthesized using octamethylcyclotetrasiloxane(D4),1,1,3,3-Tetramethyldisiloxane and allyl polyether as raw materials.Then,the silicone modified waterborne polyurethane fixing agent(HSPU)was successfully synthesized via step-by-step polymerization with isophorone diisocyanate(IPDI)and polypropylene glycol(PPG-1000)used as monomers,EGDEA as the hydrophilic monomer,Methyl ethyl ketone oxime as the blocking agent.The chemical structure of the material and the product was characterized by Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS).The main physical properties of the HSPU emulsion were determined and the synthesis process was optimized.The optimal synthetic conditions of HSPU were as follows:R value(molar ratio of NCO to OH)is 2.2,the weight of EGDEA was 8%,the weight of HS was 16%(all as a percentage of the total mass of the reaction monomer).The HSPU was applied to the fixation of cotton fabrics with reactive dyes.Finally,compared with the dyed cotton fabric without fixation,the dry rubbing fastness of the dyed cotton fabric treated by HSPU can reach 4-level,the wet rubbing fastness can reach 3～4-level,and the soaping fastness can reach 4-level,the average coefficient of dynamic friction(MIU)and the bending stiffness(G)were 0.197 and 0.309 mN·cm,respectively,which has little effect on the softness of the fabric,when the concentration of ACPU was 5%(owf),the baking temperature and time were 150℃ and 150 s,respectively.