农业工程学报2017，Vol.33Issue(8)：112-118,7.DOI:10.11975/j.issn.1002-6819.2017.08.015
助剂对聚乙烯醇缩甲醛机械性能及负压渗水性能的影响
Effects of auxiliaries on mechanical properties and negative pressure water permeability of polyvinyl formal
摘要
Abstract
In order to improve the mechanical property of negative pressure water seepage material polyvinyl formal (PVFM), 5 auxiliaries including silica, kaolin, silicone oil, silicone oil + silica, and silicone oil + kaolin, were added into PVFM, which were then moulded to water seepage tube using the mechanical foaming method. Their basic physical properties, mechanical properties, negative pressure water permeability and pore structure were characterized under negative pressure irrigation, and then, the results were compared with that of PVFM without adding auxiliaries (CK). The results showed that besides SiO2 powder, the 4 auxiliaries could improve the appearance quality of PVFM, and make the surface smooth and delicate. Adding auxiliaries could reduce the water absorbency of PVFM and increase the apparent density, true density and porosity, and the auxiliary of kaolin could significantly (P<0.05) improve the porosity and ensure a high water absorption at the same time. Compound auxiliaries could improve the mechanical properties of PVFM; the most great improvement of the hardness was 62.5% and that of tensile strength was 51.9%, which were caused by silicone oil + SiO2, and that of the elongation at break was 33.5%, which was caused by silicone oil + kaolin. Adding auxiliaries could significantly (P<0.05) improve the bubble point value of PVFM, and silicone oil + kaolin could make an increase of 70.7%. But adding these auxiliaries could not improve PVFM cumulative infiltration and infiltration rate. Only in lower negative pressure (-10 kPa), adding SiO2 into PVFM could maintain a slightly higher cumulative infiltration and infiltration rate. Adding auxiliaries could make the pore structure more uniform. Silicone oil + kaolin was the most obvious one to make pores uniform and small, and the bubbles few. In general, the 2 treatments with mixed auxiliaries simultaneously improved the appearance quality and bubble point value. The increase range was higher than that of single promoter in varying degree. SiO2 powder could improve PVFM cumulative infiltration and seepage rate under-10 kPa. This study provides a promising direction for the improvement of polymer negative pressure water seepage material.关键词
材料/机械性能/物理性能/助剂/聚乙烯醇缩甲醛/负压渗水性能Key words
materials/mechanical properties/physical properties/auxiliary/poly vinyl formal (PVFM)/negative pressure water permeability分类
化学化工引用本文复制引用
丛萍,龙怀玉,张认连..助剂对聚乙烯醇缩甲醛机械性能及负压渗水性能的影响[J].农业工程学报,2017,33(8):112-118,7.基金项目
国家高技术研究发展计划(863计划)(2013AA102901) （863计划）
