聚氨酯弹性灌浆材料的制备与性能研究

Study on preparation and properties of elastic polyurethane grouting material

以聚醚二元醇(N-220)、聚醚三元醇(N-330)和甲苯二异氰酸酯(TDI)为主要原料,合成了端-NCO基PU(聚氨酯)预聚体;然后将PU预聚体与固化剂(EP330N)、N-220、丙三醇、增塑剂、催化剂(辛酸亚锡)和填料(轻质碳酸钙)等按比例混合均匀后,制得PU弹性灌浆材料。以拉伸性能和胶接强度为考核指标,采用单因素试验法优选出制备该灌浆材料的最佳工艺条件。研究结果表明:当R=n(-NCO):n(-OH)=1.05:1、n(N-220):n(N-330)=5:1、w(增塑剂)=40%(相对于预聚体质量而言)、w(辛酸亚锡)=2%(相对于总物质的质量而言)和w(轻质碳酸钙)=30%(相对于总物质的质量而言)时,PU弹性灌浆材料既具有较大的断裂伸长率,又具有较高的拉伸强度和胶接强度,并且可用于大变形、高位移量的水泥伸缩缝、裂缝等修补。

With polyether diols(N-220),polyether triols(N-330) and toluene diisocyanate(TDI) as main raw materials,a PU(polyurethane) prepolymer with-NCO-end was synthesized.Then,an elastic PU grouting material was prepared when some materials[such as PU prepolymer,curing agent(EP330N),N-220,glycerol,plasticizer,catalys(stannous octoate),filler(light calcium carbonate) and other materials]were evenly mixed by proportion.With tensile properties and bonding strength as evaluation indices,the optimal process conditions of preparing grouting material were preferred by single-factor experiment method.The research results showed that the elastic PU grouting material had the relatively larger elongation at break,tensile strength and bonding strength,and it could be used for repairing expansion joint and crack with larger deformation or higher displacement of cement when R value or molar ratio of n(-NCO):n(-OH) was 1.05:1,molar ratio of n(N-220):n(N-330) was 5=1,mass fraction of plasticizer was 40%in prepolymer,mass fractions of stannous octoate and light calcium carbonate were2%and 30%respectively in total materials.