摘要： 以聚氨酯乳液为种子乳液,引入功能性单体十六烷基烯丙基琥珀酸双酯磺酸钠(SCASD)和环氧树脂(E-44)制备了双重改性聚氨酯丙烯酸酯复合乳液(SEPUA)。采用X-光电子能谱、粒径分析仪、热重分析仪等探讨了不同SCASD及E-44用量对乳液及胶膜性能的影响。结果表明:SEPUA胶膜中含有C、O、N、S和Na元素;随着SCASD用量的增加,乳液的Zeta电位绝对值从38.9 mV增加到48.4 mV;当SCASD用量为4%时,乳液稳定性最佳,乳液粒径呈现单峰分布,SEPUA胶膜的热分解温度逐步提高。当E-44用量为6%时,胶膜的拉伸强度为10.58 MPa,吸水率降低至8.23%,而交联度升高到81.6%。将SEPUA乳液配制成水性清漆,漆膜柔韧性优良、附着力好,随着SCASD用量的增大,漆膜光泽逐渐增大。

关键词: 双重改性, 聚氨酯丙烯酸酯, 稳定性, 耐热性, 水性清漆

Abstract:

Double modified polyurethanepolyacrylate (SEPUA)composite emulsions were synthesized by adding functional monomer sodium cetyl allyl succinic diester sulfonate(SCASD) and epoxy resin( E-44) as modified materials at the presence of polyurethane as seed emulsion. The effects of content of SCASD and E-44 on the properties of the SEPUA emulsions and films thereof were characterized by X-ray photoelectron spectroscopy (XPS),dynamic light scattering (DLS) and thermo gravimetric analysis(TGA). The results showed that the SEPUA film contained C,O,N,S and Na elements. With the increase of the content of SCASD, the absolute value of Zeta potential increased from 38.9 mV to 48.4mV.When the dosage of SCASD was 4%, the emulsion exhibited the optimal stability,meanwhile,its particle size showed unimodal distributions and the decomposition temperature of the film increased gradually. With the content of E-44 increased to 6%, the tensile strength was 10.58 MPa, the water absorption decreased to 8.23%, and the gel content increased to 81. 6%. The waterborne varnish was then prepared by using the SE PUA emulsions, and its film gave excellent flexibility and adhesion. In addition, an increasing addition of SVASD could allow the film to show an increase of gloss.

Key words: double modified, polyurethane/polyacrylate, stability, heat resistance, waterborne coating