Preparation And Performance Of Epoxy Resin Slow Adhesive

Retarded bonded prestressed technology is a new emerging type of prestressed technology in China.By comparing with the traditional prestressed concrete technology,retarded bonded prestressed technology is the cohesion of the convenient construction of the unbonded prestressed system and the excellent mechanical behavior of the bonded prestressed system.It's a breakthrough in the area of the prestressed concrete technology.The most important part of the retarded bonded prestressed technology is the creation of the specific retarded bonded material and with the fuse of the unique creating method and the mechanical measures,the new operating method different from the lubricant grease of the unbonded prestressed bars and the post filling method of the bonded prestressed bars.In recent years,the investigation of the retarded bonded prestressed technology is still in the exploring process,the bonded agent formula is not completely mature,the types are rare and the massive producing line has not been founded.The lack in the investigation in the retarded bonded prestressed technology restricts the development of the new technology.In this project,epoxide resin is the main studied material,dibutylphthalate is the plasticizer.The polyamid,the cardanol and the dicyandiamide are adopted as the solidifying agent.Moderate cement,gypsum powder and talc powder are adopted as the fillers.The creation of the epoxide resin retarded bonded agent is studied by changing the volume and type of the solidifying agent,the volume of the plasticizer and the volume of the fillers,then the solidification behavior and the mechanical behavior of the created specimen are investigated,at the sametime,the curing process and the stability are studied.It can be concluded from the research that the epoxide resin solidifying velocity with the low molecule weight polyamid is faster than the cardanol and the solidified compound of the polyamid is harder than that of the cardanol,dicyandiamide as latent type curing agent,under this experimental condition appear layered phenomenon,a month has not been cured..Two kinds of polyamide and cardanol mixed curing agent can increase the toughness of the compound.As the volume of the polyamid increases,the bending strength of the compound increases at first and then the strength decreases,the compressive strength doesn't change a lot and the shear strength decreases.When the mix ratios of the two agents are 2:3 and 3:2,the comprehensive behaviors of the compound are the best.The law of the impact of the plasticizer on different kinds of polyamids is identical and it has no influence on the rigidity of the epoxide resin solidified compound.For the same polyamid,being with or without the plasticizer has little impact on the surface drying time,compressive strength and the shear strength,but it has significant influence on the solidifying time.The type of the filler has no influence on the rigidity of the epoxide resin,the surface drying time and the hardness of the solidified compound,however it has great impact on the solidifying time,the bending strength and the shear strength of the solidified compound.The initial rigidity of the retarded bonded agent is 0 and as the solidification reaction proceeds,the rigidity increases.In the initial period of the reaction,the retarded bonded agent presents in the sticky condition.After the reaction,the viscosity of the retarded bonded agent is 0,the rigidity of the retarded bonded agent reaches its maximum value and the mechanical behavior becomes the best.The retarded bonded agent has better stability and environmental tolerance.The advantage can maintain the using performance of the retarded bonded prestressed bars in different environments and the durability,the safety and the reliability of the structure.Through the experiment,the best mix proportion of the epoxide resin retarded bonded agent is proposed as follows,epoxide resin 25%,solidifying agent 12%,dibutylphthalate 2%,solvent 5%,filler 56%.