建筑用改性双酚A型环氧树脂结构胶的制备及性能研究

Preparation and properties of modified bisphenol A epoxy resin structural adhesive for prefabricated construction

针对目前装配式建筑采用的环氧树脂粘结剂其弹性模量低、脆性大的缺点,通过在环氧树脂结构胶中添加纳米碳酸钙和硅微粉,并对改性后环氧树脂结构胶抗拉、抗压、流淌性能进行了试验研究。试验结果表明,低掺量的纳米碳酸钙可以显著地改善其抗拉性能,而高掺量的纳米碳酸钙对结构胶拉伸强度改善作用不大;硅微粉能够提升建筑用改性环氧树脂结构胶抗压强度,当结构胶位移小于3 mm时,5%的硅微粉掺量比3%的硅微粉掺量的结构胶抗压强度高。当结构胶位移大于3 mm时,5%的硅微粉掺量比3%的硅微粉掺量的结构胶抗压强度低;当水泥∶纳米碳酸钙∶硅微粉=17∶10∶3.2时,改性后环氧树脂结构胶无流淌;改性后的环氧树脂结构胶具有良好力学性能,适用于建筑结构植筋、砼孔洞、裂缝、蜂窝露筋等损坏修补修复。

In view of the shortcomings of low elastic modulus and high brittleness of the epoxy resin adhesives commonly used in the process of prefabricated construction,nano-sized calcium carbonate and silicon powder were added to the epoxy resin structural adhesives to study the tensile,compressive and flow properties of the modified epoxy resin structural adhesive.The experimental results show that the low content of nano-calcium carbonate can significantly improve the tensile property of structural adhesive,while the high content of nano-calcium carbonate has little effect on the improvement of tensile strength of structural adhesive.The silicon powder can improve the compressive strength of the modified epoxy resin structural adhesive used in building.When the displacement of structural adhesive is less than 3 mm,the compressive strength of structural adhesive with 5% silica powder content is higher than that with 3% silica powder content.When the displacement of structural adhesive is greater than 3mm,the compressive strength of structural adhesive with 5% silica powder content is lower than that with 3% silica powder content.When the cement∶nano calcium carbonate∶silicon powder=17∶10∶3.2,the modified epoxy resin structural adhesive does not flow;it can be concluded that the modified epoxy resin structural adhesive has good mechanical properties and is suitable for repairing damage such as steel bars,concrete holes,cracks,honeycomb exposed steel bars,etc.in building structures.