聚氨酯的生态固沙性能及其与聚醋酸乙烯酯乳液的对比

Ecological Sand-Fixing Properties of Polyurethane Along Comparison with Polyvinyl Acetate Emulsion

研究聚氨酯用于漠化治理的技术依据,从固沙性能和生态效应两方面,详细探讨了聚氨酯用于生态固沙的综合效果,并与聚醋酸乙烯酯乳液的对应性能进行了对比。研究结果表明,在使用浓度为2%时,2种材料的固沙强度均能满足固沙的基本要求,而且均有良好的耐热稳定性与抗冻融稳定性,从而能够经受沙漠环境温差的大幅度变化;另外,2种固沙材料都可提高沙土的保水性能,有利于沙土微生物的生长以及植物发芽率的提高。对比2种固沙材料可知,聚醋酸乙烯酯对提高植物的发芽率以及沙土微生物的生长有更明显的促进作用;聚氨酯与沙粒可形成韧性固结层,能进一步提高其抗风沙侵蚀的能力,同时聚氨酯有更好的保水性,能促进沙土中细菌的生长及延长植物的存活时间,但对种子的前期发芽有一定的延缓作用。

This paper mainly focused on the potential use of polyurethane（PU） in ecological sand-fixation. A detailed investigation was conducted for illuminating both the sand-fixing properties and ecological effect of polyurethane, and for knowing PU better, the comparison between PU and polyvinyl acetate emulsion （PVAc） was also made in the related properties. The experimental results show that when the using concentration of PU and PVAc is above 2%, both the PU and PVAc present not only the sand stabilization strength to meet the requirement of sand-fixation, but also good thermal and freeze-thaw stability to withstand the big changes in temperature of Sandy Land. Moreover, PU and PVAc can both improve the water-holding capacity of sandy soil to benefit the growth of microorganisms and the improvement of seed germination rate. By comparison between PU and PVAc, it is found that PVAc is more helpful than PU for the growth of sandy soil microorganisms and the improvement of seed germination rate. However, the consolidated layer of PU with sand has more flexibility for further improving the resistance to wind erosion. And, PU has better water-holding capacity to promote the growth of sandy soil bacteria and prolong the survival of plants, but it delays seed germination to a certain extent.