高强度双组分聚氨酯堵水加固灌浆料研究

Study on the high-strength two-component polyurethane grouting mateials for water plugging and reinforcement

以三种分子质量(375、500及700)的三官能度聚醚多元醇与异氰酸酯按照不同的—NCO与—OH基团的物质的量比(R_(x))制备了双组分聚氨酯灌浆料,研究了多元醇分子质量及R_(x)对灌浆料初始粘度、凝固时间及力学性能的影响,并通过动态机械分析对固结体的阻尼性能进行了测试。结果表明:多元醇分子质量对灌浆料固结体性能的影响比R_(x)显著,适当增加分子链长度可明显改善灌浆料固结体的韧性。灌浆料的凝固时间对粘接强度有重要影响,随着凝固时间延长,粘接强度急剧降低。多元醇分子质量为500,R_(x)为1.4时,灌浆料综合性能最佳,其初始粘度为264 mPa·s,固结体压缩强度52.4 MPa,拉伸强度41.3 MPa,断裂伸长率6.3%,且固结体阻尼性能良好。通过调整凝固时间,灌浆料的粘接强度可达3.58 MPa。

The two-component polyurethane grouting materials were prepared with three molecular weights(375,500 and 700)of trifunctional polyether polyols and isocyanates according to different molar ratios of —NCO and —OH groups(R_(x)). The effects of the molecular weight of polyols and R_(x)on the initial viscosity,gel time and mechanical properties of the grouting materials were investigated,and the damping properties of the solidified materials were tested by dynamic mechanical analysis. The results showed that the molecular weight of polyols had a more significant effect on the properties of the solidified materials than R_(x),and appropriately increasing the molecular chain length could significantly improve the toughness of the grouting materials. The gel time of the grouting material had an important influence on the bonding strength. With the increasing of the gel time,the bond ing strength was decreased sharply. When the molecular weight of the polyol was 500 and the R_(x)was 1.4,the comprehensive performance of the grouting material was the best and the initial viscosity was 264 mPa·s. The compressive strength,tensile strength and elongation at break of the solidified materials was 52.4 MPa,41.3 MPa and 6.3%,respectively and the damping performance was good. By adjusting the gel time,the bonding strength of the grouting material could reach 3.58 MPa.