【作者】 黄新丽；

【导师】 陈明凤；

【作者基本信息】 重庆大学 ， 材料科学与工程， 2007， 硕士

【摘要】 近年来,外墙乳胶涂料作为一种方兴未艾的外墙装饰材料,以其色彩丰富、施工简便、维护更新容易、饰面灵活多样、自重轻、安全可靠、环保等特点,能满足保护和装饰要求,正在成为主导的建筑物饰面材料。虽然外墙乳胶涂料有其独特的优势和巨大的发展空间,但外墙乳胶漆要在外墙装饰中唱主角,还面临着巨大的性能考验,尤其是耐沾污性差制约了外墙乳胶涂料的大面积推广应用,因此提高外墙乳胶涂料的耐沾污性势在必行。本论文采用两条技术途径提高外墙乳胶涂料的耐沾污性:①从粒子设计观点出发,控制核壳乳胶粒结构、形态,研究核壳乳液对涂料性能的影响。核壳乳液核、壳层合成均采用软硬单体复配的方法以调节核壳层的玻璃化温度,改善乳液的成膜性能和耐沾污性。通过对比市售乳液、自制常规乳液、内软外硬及内硬外软核壳乳液性能,数据表明内软外硬核壳乳液耐沾污性最优异,并明确了内软外硬核壳乳液合成所用的核壳比及核、壳层中的软硬单体比。②采用化学改性方法,在内软外硬核壳乳液壳层中引入交联单体、硅系单体、氟系单体等,改善核壳乳液外墙涂料的耐沾污性。在乳液壳层聚合时掺加交联单体甲基丙烯酸羟乙酯(HEMA)、甲基丙烯酸(MAA),含氟单体甲基丙烯酸六氟丁酯、甲基丙烯酸十二氟庚酯,硅烷偶联剂单体乙烯基三乙氧基硅烷(WD-21)、ν-(甲基丙烯酰氧)丙基三甲氧基硅烷(KH570),八甲基环四硅氧烷(D4)与乙烯基三乙氧基硅烷(WD-21)配合使用及壳层聚合时含氟乳化剂与非离子乳化剂、阴离子乳化剂配合使用等诸多化学改性方法对核壳乳液壳层进行改性。经大量实验反复验证,HEMA的引入对漆膜的耐沾污性提高效果显著,HEMA在壳层单体中的掺量以壳层单体总量的1.5%为宜;掺加六氟丁酯能够提高涂料的耐沾污性,其适宜掺量为壳层单体总量的6% ;WD-21掺量在2%时,对改善涂料的耐沾污性有效;将有机硅D4与硅烷偶联剂WD-21配合使用,有机硅D4的掺量为壳层单体总量的3%,硅烷偶联剂WD-21的掺量为有机硅单体的5%时为宜;含氟乳化剂与阴离子、非离子乳化剂配合使用,含氟乳化剂用量为乳化剂总量的10%时,能够达到改善涂料耐沾污性的目的。更多还原

【Abstract】 Recently, exterior emulsion coating has been more and more used in the decoration of walls. It has been also a sort of dominantly decorative material depending on its variety of colors, convenience of painting, easiness of maintenance, lightness of deadweight, non-pollution of environment. Although having been extensive applied, exterior emulsion coating also is facing with huge challenges, especially its stain resistance. So it is imperative to enhance the stain resistance of coating under the situation.In this paper, two technical methods are introduced to enhance the stain resistance. One is, on the basis of“the latex particle design”, controlling the structure and form of latex particles to do research on the influence of properties of coating by the core-shell emulsion. To adjust the Tg of the emulsion and improve its film quality and the stain resistance, soft monomers and hard monomers are mixed in the polymerization of core and shell of latex particles. Comparing soft-core/hard-shell, hard-core/soft-shell and common latex with latex sold in the market, it proves that soft-core/hard-shell latex is the best in view of the stain resistance, and makes certain the ratios of core to shell and soft monomers to hard monomers in the polymerization. The other is adopting chemical methods to improve the stain resistance of coating by mixing cross-linking monomers, silicon, fluorid monomers in the shell-polymerization of soft-core/hard-shell latex. The mixed monomers in the shell include HEMA, MAA, HFMA, WD-21, KH570, D4. Moreover, fluorid emulsifier, used with common emulsifiers, will take effect in the polymerization.After a great deal of experiments, conclusions have reached: the stain resistance of coating is enhanced effectively after mixing HEMA, its dosage is 1.5 percent of shell-polymerization monomers; HFMA, WD-21 also have partly improved the stain resistance, their dosages are separately 6 percent and 2 percent of monomers; When fluorid emulsifier, compounded with common emulsifiers, is 10 percent of gross of emulsifiers, it has an effect on polishing up the stain resistance.更多还原