淀粉基保水剂的选择设计及其保水固沙性能

Synthesis and Design of Starch Based Superabsorbent Polymer and Its Water-Retaining and Sand-Fixing Properties in Sandy Soil

为开发一种适宜于沙土中应用的保水剂,以淀粉、丙烯酸为基材,碳酸钾为中和剂,采用辐射法合成了一种淀粉/聚丙烯酸钾保水剂材料,研究了原料配比、中和度、辐照剂量对吸水性能的影响;利用离心法分析了保水剂的保水性能;采用沙土应用探讨了保水剂的持水性能、固沙性能.结果表明,得到良好吸水性能淀粉/聚丙烯酸钾保水剂的配方为淀粉与丙烯酸配比1∶3、中和度80%、辐照剂量7kGy.淀粉与丙烯酸配比、中和度、辐照剂量对保水剂的保水性能有显著影响,3次离心保水率均随淀粉与丙烯酸配比的减小而增大,随中和度以及辐照剂量的增大呈先增大后减小的趋势,离心次数对离心保水率的影响不明显.施用保水剂对沙土的持水性能有显著影响,累计水分蒸发率随着保水剂用量的增大而减小,用量1g、2g、3g间有显著差异,3g、4g、5g间差异不显著.保水剂对沙土的固沙性能有显著影响,风蚀模数随着保水剂用量的增大显著降低.综上,该试验中适宜的工艺条件下制备的淀粉基保水剂具有良好的吸水、保水、持水性能和固沙性能.该研究为保水剂在荒漠化治理方面的应用提供理论参考和科学依据.

The superabsorbent polymer(SAP)for water retaining in agriculture and forest is gradually applied to agricultural and forestry production,which has bright application prospects of improving soil,soil and water conservation,improving fertilizer use efficiency,increasing the survival rate of afforestation,increasing crop yield,preventing wind and fixing sand.In order to develop a kind of superabsorbent polymer suitable for application in sand soil,a starch-polyacrylate potassium superabsorbent polymer was synthesized by irradiation method with starch and acrylic acid as the base material and potassium carbonate as the neutralizer.The effects of raw material ratio,neutralization degree and irradiation dose on water-absorbing property of superabsorbent polymer were considered.The centrifugal method is used to analyze the water-retaining property of the superabsorbent polymer and the sand-soil application is used to discuss the water-holding and sand-fixing properties of the superabsorbent polymer.The results showed that the formulation of starch based superabsorbent polymer with good water absorption performance was that the ratio of starch to acrylic acid was 1∶3,the neutralization degree was 80%,the irradiation dose was 7 kGy.The ratio of starch to acrylic acid,neutralization degree and irradiation dose have significant effects on the water-retaining property of the superabsorbent polymer.The three repeated centrifugal water retention rates of superabsorbent polymer were increased with the decrease of the ratio of starch to acrylic acid,and were increased first and then decreased with the increase of degree of neutralization and irradiation dose.The influence of centrifugation times on the centrifugal water retention rate was not obvious.In addition,the influence of superabsorbent polymer on the water-holding capacity of sand soil was significant.The cumulative moisture evaporation rate was decreased with the increase of the amount of superabsorbent polymer,and there were significant difference between the amounts of 1 g,2 g,and 3 g,and there was no significant difference between 3 g,4 g,and 5 g dosage.However,the superabsorbent polymer has a significant impact on the sand-fixing capacity of sandy soil.The wind erosion modulus of sandy soil was decreased significantly with the amount of superabsorbent polymer increased.In summary,the starch-polyacrylate potassium superabsorbent polymer prepared under suitable technological conditions had good water-absorbing,water-retaining,water-holding,and sand-fixing properties.In this study,the results were intended for providing theoretical reference and scientific basis for the application of superabsorbent polymers in desertification control.