| Due to high adhesion strength and extensive usage, the room curing epoxy adhesives have been widely used in construction area. The room temperature curing epoxy adhesives are easy to fierce polymerize when the temperature is higher or the amount of mixture adhesive is huge. However, the adhesion properties would decrease when it is cured in the water. All of the shortages would make the adhesives not be suit for the requirement of operation technology and also limit the usage of the room curing adhesive. The synthesis of different kinds of epoxy room temperature curing agents and the combine of main materials, curing agents and other auxiliary agents could be used to produce the new kinds of adhesives of different characters. The study of producing new curing agents using the methods of modification is very popular these days. The different reaction stuff and condition would have a deep effect on the properties of curing agents. The development of new modification method and new materials would be the research hot topics in the modification of epoxy adhesive curing velocity. We bring out the methods of mannich reaction on amines to produce the room temperature curing agents and it had been used in the combination with other agents to produce the curing controlling adhesive and under-water adhesive. The study content is described as follows:The first step is the Mannich modification of amines as curing agent: after the analysis of mannich reaction and influencing factor, The synthesize of different molecule structures curing agents based on the aliphatic amines, alicyclic amines and aromatic amines, mix amine, has been done by the mannich reaction. The physical properties of derived amine curing agent had been researched and so did the curing technological and strength properties when the curing agent had been mixed with the epoxy main material and other auxiliary agents. The results shows that the shear strength of the aliphatic amines cured epoxy adhesive could reach at the level which is higher than 20MPa, while the alicyclic amines is less than 7MPa, while the epoxy could not be cured by derived aromatic amines if the amines is linked to the aromatic ring directly. The phenols also have certain effect on the curing velocity. The curing velocity would become slower when the carbon chain numbers of phenols increased.Then we developed the study of controlling cured adhesive: The orthogonal test and solo-factor analysis method had been used to test the effect of every component on the adhesive curing properties and find out the condition of accelerating epoxy curing reaction: when we use biphenyl F instead of biphenyl A, NBR as roughing agents, and the material containing active hydrogen atomic, such as water and DMP—30 would accelerate the solidifying rate, while the kerosene could be used to slow the curing agents. Combining the alicyclic amine and polyether amines with the quick curing agents would regulate the surface curing time at 1 to 20 hours while the solid time could at the range of 3 to 36 hours. The properties of produced cured construction adhesive could meet the standard of China national request of I kind of construction adhesive.The last step is the manufacture of under-water curing adhesive: The PF and acrylonitrile methods have been used to modificate the liquid long chain aliphatic amine in the producing of under-water curing agents. The better reaction time is about 3.5 to 4hours, while the shear strength could reach a value when the ratio of acrylonitrile and amines is 1.5. The curing agents had been mixed with different epoxy resin and roughing agents to produce the under-water adhesive. Compared with the under-water adhesive in the market, the out coming shows that these adhesives have higher strength at about 17.9MPa or 9.9MPa, which is higher or closer to the adhesive in market.
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