Study On The Synthesis And Durability Of Fluorined Water And Oil Repellent Finishing Agent

The fluorine-containing finishing agent is an important part of multi-function textile finishing agent. Because of its very low surface free energy and surface friction coefficient, which has excellent " triple-proofing " characteristics. They have been widely used for the apparel fabrics, home furnishing fabrics and industrial fabrics field. The finished fabric with water and oil repellency, antifouling performance can keep the original color, fabrics handle, permeability and wettability. But after being washed, the water and oil repellent effect was reduced obviously, the function of durability was not ideal, which caused a large number of consumption waste. In order to reduce costs, save energy and protect the environment, it is of great importance to make deeper research of the improvement of water and oil repellent the ascension of the durability. So that the textile won’t be thrown away with the loss of function early in use process, reduce the waste of resources, make the function of the finished products more ecological security, and to promote the harmonious development of humanity and resources.In this paper, fluorinated acrylic polymer emulsion was synthesised by the method of emulsion polymerization. The micro-jet pre-emulsification technology was used in experiment. The application of different quantity containing fluorine monomer and the non-fluorine monomer, different emulsion system made water and oil repellent agent. The synthetic technological conditions were studied in details. The performance test and structure characterization of fluorinated acrylic polymer emulsion was studied. Application of different kinds of water and oil repellent agents added different types of crosslinking agents on the polyester fabrics and cotton fabrics for water and oil repellent finishing, the durability of the fabrics was studied.The experiment results show that the optimum synthesis process was that pre-emulsification technology pressure was15000psi, the pre-emulsification times were2, the fraction of containing fluorine monomer was15%, the fraction of non-fluorine monomer was10%, the fraction of cationic and nonionic type-specific emulsifier was5%,2,2’-azobis (2-methylpropionamidine) dihydrochloride was used as initiator, two steps addition method was used, the time of polymerization was10h, the temperature of polymerization70℃, the stirring speed of polymerization was100r/min. The finishing agent of fluorinated acrylic polymer emulsion was characterised by infrared spectrum (IR). The analysis showed that the C-F bond was existed in the fluorinated acrylic polymer emulsion finishing agent, the containing fluorine monomer involved in the polymerization reaction. The particle size of finishing agent was uniform distribution in50to58nm. The range of finishing agent was narrow. The Average Zeta potential of finishing agent was13.06mV and the stability was good. The finishing agent positively charged, the average moved conductivity of finishing agent was1.018e-004cm2/Vs. The contact angle to water and oil of polyester fabrics after treated could be reached149.04°and137.53°respectively. The contact angle to water and oil of cotton fabrics after treated could be reached142.28°and128.79°respectively.The optimum processes for polyester fabrics were that the dosage of water and oil repellent finishing agent was50g/L, the dosage of cross-linking (six hydroxymethyl three hydroxy methyl melamine methyl etherification initial shrinkage body) was4g/L or crosslinking agent (UN125F)20g/L, curing temperature was160℃, and curing time was90s. The contact angle of fabrics after treated were more than140°and130°. After10times’being washed, the rate of descent of contact angel of the fabrics finished with the cross-linking agent was less than10%. The optimum processes for cotton fabrics were that the dosage of water and oil repellent finishing agent was50g/L, the dosage of crosslinking agent (UN125F)15g/L, curing temperature was150℃, and curing time was210s. Add crosslinking agent, the contact angle to water and oil of fabrics after10times’ washed was more than130°and110°. The durability of finished cotton fabrics was good.After20times’ being washed, the rate of descent of contact angel to water and oil of the cotton fabrics finished with the cross-linking agent (modified isocyanate) was13.39%and11.15%respectively less than that without cross-linking agent. In addition, the fabrics were after being finished, cold and warm temperature was not greatly changed. The fabrics also take good performance indicators.