生物胶—黄土复合材料的制备及保水固沙性能研究

发布时间：2018-12-16 14:48

【摘要】：土地沙漠化是当今世界最为严峻的生态问题,干燥少雨的沙漠化环境对我国人民生产生活造成了严重影响,对生态脆弱的沙区进行生态环境修复是我国可持续发展战略急需解决的问题之一。目前,普遍采用的固沙方式有工程固沙、生物固沙和化学固沙。化学固沙适用于环境恶劣,不易进行工程固沙和生物固沙的地区,因其具有可机械施工、简单快速、固沙效果立竿见影的特点,近年来得到了很大的发展。保水材料能够吸附其自身成百甚至上千倍的水,具有较强的耐酸碱性及耐高温性能,特别适合高温少雨的沙漠环境。本论文应用环境友好的生物质高分子材料瓜儿胶、黄原胶,以及自然界广泛分布、储量丰富的天然黄土为主要原料,复配环境友好型高分子,制备了两种有机-无机复合高分子材料,并应用于保水和固沙研究。主要内容如下:1.以瓜尔胶(GG)、丙烯酸(AA)和黄土(loess)为原料,过硫酸铵(APS)为引发剂,N,N'-亚甲基双丙烯酰胺(MBA)为交联剂,采用水溶液聚合法制备了瓜尔胶接枝聚丙烯酸/黄土(GG-g-PAA/loess)复合高吸水性树脂。采用FTIR和SEM对其结构进行了表征,研究了黄土的添加量对复合高吸水性树脂的溶胀能力和溶胀动力学的影响,考察了复合高吸水性树脂的保水性能、反复溶胀性以及在不同pH溶液中的吸水性能。结果表明:瓜尔胶、丙烯酸和黄土发生了接枝共聚,体系中引入黄土能够显著提高复合高吸水性树脂的吸水性能。当黄土的含量为2%时,该树脂最高吸水倍率可达602 g/g,室温下6 d后,其保水率仍达28%,5次反复溶胀,吸水倍率仍能保持初始时的49%。此外,该复合高吸水性树脂还表现出优异的pH稳定性。2.以黄原胶(XG)、丙烯酸(AA)和黄土(loess)为原料,过硫酸铵(APS)为引发剂,N,N'-亚甲基双丙烯酰胺(MBA)为交联剂,采用水溶液聚合法制备了黄原胶接枝聚丙烯酸/黄土(XG-PAA/loess)复合高吸水性树脂。采用FTIR和SEM对其结构进行了表征,考察了黄土的含量、pH值、表面活性剂、盐以及温度对复合高吸水性树脂的溶胀能力和保水性能的影响。结果表明:该复合高吸水性树脂表现出了优异的吸水性能(610 g/g在蒸馏水中)、pH稳定性(pH 5-10)以及在阴离子表面活性剂溶液中更高的溶胀性能。此外,该复合高吸水性树脂还可用于对溶液中多价金属离子的去除。3.以瓜尔胶(GG)、丙烯酸(AA)和黄土(loess)为原料,应用与第一部分类似的制备方法,制备了新型的有机-无机复合化学固沙剂(GG-g-PAA/loess)。考察了固沙剂的用量对固沙性能的影响,并对固沙试样的耐紫外老化性、热老化、抗冻融性、保水性进行测试。结果表明,这种化学固沙剂能够显著提高固沙试样的抗压强度,固沙试样具有良好的耐热性、抗冷冻-融性和抗紫外老化性。除此之外,用固沙剂处理的沙洋还表现出了优异的保水性能。
[Abstract]:Desertification is the most serious ecological problem in the world today. The dry and rainy desertification environment has a serious impact on the production and life of the people in our country. The restoration of ecological environment is one of the urgent problems in sustainable development strategy of our country. At present, the commonly used sand fixation methods are engineering sand fixation, biological sand fixation and chemical sand fixation. Chemical sand fixation is suitable for the areas where the environment is bad and it is not easy to carry out engineering and biological sand fixation. Because of its characteristics of mechanical construction, simplicity and rapidity, the effect of sand fixation has been greatly developed in recent years. The water-retaining material can adsorb hundreds or even thousands times of its own water, and has strong acid and alkali resistance and high temperature resistance, especially suitable for desert environment with high temperature and little rain. In this paper, environment-friendly biomaterials such as guar gum, xanthan gum and natural loess, which are widely distributed in nature, are used as main raw materials. Two organic-inorganic composite polymer materials were prepared and applied to water conservation and sand fixation. The main contents are as follows: 1. Guar gum (GG), acrylic (AA) and loess (loess) were used as raw materials, ammonium persulfate (APS) as initiator, NN- N- methylene bisacrylamide (MBA) as crosslinking agent. Guar grafted polyacrylic acid / loess (GG-g-PAA/loess) superabsorbent resin was prepared by aqueous solution polymerization. The structure of the composite superabsorbent resin was characterized by FTIR and SEM. The influence of the content of loess on the swelling ability and swelling kinetics of the composite superabsorbent resin was studied, and the water retention property of the composite superabsorbent resin was investigated. Repeated swelling and water absorption in different pH solutions. The results showed that the graft copolymerization of guar gum, acrylic acid and loess took place, and the water absorbency of composite superabsorbent resin could be improved by introducing loess into the system. When the content of loess is 2, the maximum absorbency of the resin can reach 602 g / g. After 6 days at room temperature, the water retention rate of the resin is still up to 28% and 5 times of repeated swelling, and the absorbency of the resin can still keep the 49g / g ratio of the initial stage. In addition, the composite superabsorbent resin also showed excellent pH stability. Xanthan gum (XG), acrylic (AA) and loess (loess) were used as raw materials, ammonium persulfate (APS) as initiator, NN- N- methylene bisacrylamide (MBA) as crosslinking agent. Xanthan gum graft polyacrylic acid / loess (XG-PAA/loess) superabsorbent resin was prepared by aqueous solution polymerization. The structure of the composite superabsorbent resin was characterized by FTIR and SEM. The effects of content of loess, pH value, surfactant, salt and temperature on the swelling and water retention properties of the composite superabsorbent resin were investigated. The results show that the composite superabsorbent resin exhibits excellent water absorbency (610g / g), pH stability in distilled water (pH 5-10) and higher swelling property in anionic surfactant solution. In addition, the composite superabsorbent resin can also be used to remove polyvalent metal ions in solution. A novel organic-inorganic compound chemical sand fixation agent (GG-g-PAA/loess) was prepared by using guar gum (GG), acrylic (AA) and loess (loess) as raw materials. The effects of the amount of sand fixing agent on the properties of sand fixation were investigated, and the UV aging resistance, thermal aging, freezing and thawing resistance and water retention of sand fixation samples were tested. The results show that the chemical sand fixation agent can significantly improve the compressive strength of the sand fixation sample, and the sand fixation sample has good heat resistance, freeze-melting resistance and UV aging resistance. In addition, the sand with sand fixation agent also showed excellent water retention performance.
【学位授予单位】：西北师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB332

【相似文献】