聚氨酯-含氟丙烯酸酯防水防油性复合乳液的制备及性能

Synthesis and properties of polyurethane-fluorinated acrylate hybrid emulsion as water and oil-repellency agent

以自乳化自交联的阳离子水性聚氨酯乳液(PU)为种子乳液进行含氟丙烯酸酯(FA)、苯乙烯(St)和丙烯酸丁酯(BA)等乙烯基单体的自由基共聚合,制得阳离子聚氨酯-含氟丙烯酸酯(FPUA)复合乳液。通过红外光谱分析、接触角测试、表面自由能计算、粒径及粒径分布测试及透射电镜测试对聚合物乳液及其膜结构与性能进行了表征。结果表明w(FA)达到20%左右,FPUA才兼具良好防水防油性;水和二碘甲烷在FPUA(w(FA)=20%)乳胶膜上所成接触角分别为110和86°;计算得30℃时FPUA(w(FA)=20%)乳胶膜表面自由能为14.64mJ/m2,比改性前PU膜表面自由能下降78.65%;120℃热处理后FPUA(w(FA)=20%)表面自由能可进一步降低17.69%;FPUA乳液粒径较PU明显增大且分布变宽;推测FPUA复合粒子既有胶束成核又有水相成核机理。

Novel cationic polyurethane-fluorinated acrylate（FPUA） hybrid emulsion was prepared with the copolymerization of fluorinated acrylate（FA）,styrene（St） and butyl acrylate（BA） in the medium of cationic polyurethane（PU） emulsion.The structure and properties of the emulsion and latex of FPUA were characterized by FT-IR,contact angle measurements,submicron particle size analyzer and TEM respectively.The results show that only the FA content is beyond 20%,FPUA can have good water and oil-repellency at the same time.The contact angle of water and CH2I2 on the FPUA（w（FA）=20%） film can achieved 110 and 86° respectively.The surface free energy of the FPUA（w（FA）=20%） film annealed at 30℃ is 14.64mJ/m2 which decreased 78.65% in contrast with PU film.Moreover,the treatment of the films with high temperature can decrease the surface free energy by more than 17.69%.The results of submicron particle size analyzer and TEM indicate the particle size of FPUA is bigger than PU emulsion and wider in particle size distribution.Mechanism of core-forming of FPUA hybrid emulsion is discussed at last.