【作者】 熊婷；

【导师】 钟安永；

【作者基本信息】 四川大学 ， 高分子化学与物理， 2007， 硕士

【摘要】 本文通过种子乳液聚合方法,合成了含有双丙酮丙烯酰胺(DAAM)功能单体的乳液,添加己二酰肼(ADH),制成核壳结构的单组分室温可固化聚丙烯酸酯乳液。把纳米硅溶胶与制得的室温自交联聚丙烯酸酯乳液不同比例共混,并对这些乳液及其乳胶膜的性能进行了测试。对乳液粘度测试的结果表明:室温自交联聚丙烯酸酯乳液及共混乳液都是假塑性流体。随着纳米硅溶胶含量的增加,共混乳液的表观粘度(ηa)、稠度系数(K)、零剪切粘度(η0)均增加,而流动指数(n)减小;且放置两天的共混乳液比未放置的ηa、K、η0变大,n变小。应用红外光谱分析(FT-IR),证明了乳液固化时酮羰基和酰肼基的交联反应以及共混乳胶膜中硅氧键的存在;测试了乳胶膜的耐水性、耐溶剂性、热粘温度、硬度、抗冲击强度等性能,结果表明:加入DAAM可以提高乳胶膜的上述性能;纳米硅溶胶的加入进一步优化了这些性能。对乳液进行钙离子稳定性测试及冻融稳定性测试,结果表明:室温自交联聚丙烯酸酯乳液及其共混乳液均通过测试。用扫描电镜(SEM)对乳胶膜的形貌表征,结果表明:纳米硅溶胶的加入改变了聚丙烯酸酯乳胶膜的形貌,并随着纳米硅溶胶含量的增加,由形貌均匀性变为微观不均匀性的变化越大。用激光散射的方法测定了乳液的粒径大小及分布,结果表明:纳米硅溶胶的加入并未改变乳液的粒径大小及分布。用差热分析(DSC)对乳胶膜进行测试,室温自交联聚丙烯酸酯乳液乳胶膜的玻璃化转变温度(Tg)比传统乳液有较大幅度提高,而纳米硅溶胶的加入更进一步提高了共混乳液乳胶膜的玻璃化转变温度。可见,本论文中合成的水性室温自交联聚丙烯酸酯乳液在保留了其优越的环保性能,节省能耗的基础上,有效地提高了传统聚丙烯酸酯乳液的性能和乳胶膜性能;而纳米硅溶胶的加入使得室温自交联聚丙烯酸酯乳液及共混乳液乳胶膜的一系列性能得到进一步改进,有望在塑料、木器表面涂装。更多还原

【Abstract】 An aqueous ambient crosslinkable polymer acrylic emulsion was abtained by adding adipic acid dihydrazide(ADH) to the polyacrylate emulsion incorporating diacetone acrylamide(DAAM), and this emulsion was synthesized by seeded-emulsion polymerization.As a consequence, a kind of white fluid polyacrylate emulsion was obtained. Then, blending nano-silica sol with this aqueous ambient self-crosslinkable polyacrylate emulsion in different ration.The emulsions and its latex films were characterized with rheologica measurements, Laser Light Scattering, Fourier transform infrated (FTIR), Scanning electron microscopy(SEM), Differential Scanning Calorimetry(DSC) and so on.The viscosities of the emulsion were measured with a NXS-ⅡA rotational viscometer. The results showed that the aqeous ambient self-crosslinkable polyacrylate emulsion and the emulsions blending with nano-silica sol are pseudoplastic fluid. The apparent viscosity (ηa), consistency factor(K), zero shear viscosity(η0) increased with increasing the silica sol content, but the emulsion flow index(n) is decreased. The apparent viscosity, consistency coefficient, zero shear viscosity of the emulsion after being laid two days increased but the flow index is decreased compared with the emulsion with the same silica sol content without laying.Fourier-transform infrared (FTIR) spectrometer was used for examining the room-temperature curing process of the crosslinkinkable acrylate resin, and for verifying reaction of carbonyl groups and hyrazide groups, also the presence of nano-silica sol. In this paper the tests for the latex it was shown that the hardness, impact strength, thermo-tacky temperature, water resistance and degree of cross-linking of the film rose with the copolymerization of DAAM, and blending emulsion increased with the nano-silica sol content.The aqueous ambient self-crosslinkable polyacrylate emulsion obtained by ADH to the polyacrylate emulsion incorporating DAAM, and blending with nano-silica sol passed the stability of calcium ion and gelation-thaw.SEM was employed to characterize the forms of the films. And the results indicated that the nano-silica sol could change the form of latex film with the content increasing the change increasing.The particle size and particle size distribution (PSD) of the emulsions were measured using a laser scattering. The results showed the presence of nano-silica sol did not change the particle sizes and PSD of aqueous ambient self-crosslinkable polyacrylate emulsion.DSC test method was used for investigation of the glass transition temperature (Tg) of the latex films. The results showed that the aqueous ambient self-crosslinkable polyacrylate emulsion was enhanced considerably the glass transition temperature of traditional polyacrylate emulsion. And the glass transition temperature of the emulsions enhanced more by bleding nano-silica sol with ambient self-crosslinkable polyacrylate emulsion.Therefore, the aqueous ambient crosslinkable polyacrylate emulsion containing DAAM with carbonyl groups and ADH with hydrazide groups have not only friendly environment property, minimization of the energy, but also good performance property than traditional polyacrylate emulsion. These properties were modified further by blending nano-silicasol with aqueous ambient crosslinkable polyacrylate emulsion.更多还原