Method for preparing liquid alkali-free accelerator through esterification and compounding of polycarboxylic acid

Abstract

The invention relates to a method for preparing a liquid alkali-free accelerator by esterification and compounding of polycarboxylic acid, which comprises the following steps: carrying out ring-opening polymerization on a cyclic amide monomer, carrying out esterification reaction on the cyclic amide monomer and polycarboxylic acid to synthesize a carboxyl-ammonia organic complexing agent, and compounding other components to prepare the liquid alkali-free accelerator, namely, carrying out ring-opening polymerization on the cyclic amide monomer to obtain a polymer main chain; then carrying out esterification reaction with polycarboxylic acid to obtain a carboxyl-ammonia organic complexing agent, and compounding the carboxyl-ammonia organic complexing agent with components such as aluminum sulfate and montmorillonite powder to obtain the liquid alkali-free accelerator. The carboxyl-ammonia organic complexing agent component prepared based on molecular structure innovative design combines the performance advantages of cyclic amide polymer and polycarboxylic acid, and the composite polyfunctional group has excellent ion complexing ability, so that the problems of poor stability, low energy efficiency, insufficient aluminum ion capacity and the like of the accelerator can be obviously improved; the prepared liquid alkali-free accelerator can greatly shorten the setting time of a cement-based material and improve the early strength, and has excellent application potential and development prospect.

Description

technical field [0001] The invention relates to the technical field of a liquid alkali-free quick-setting agent for cement concrete, in particular to a ring-opening polymerization of a cyclic amide monomer, which is then combined with a polycarboxylate to form a carboxyamine organic complexing agent, and then compounded with multiple components to obtain The specific preparation method of the liquid non-alkali quick-setting agent. Background technique [0002] With the progress of building materials and construction engineering technology and the continuous increase of market demand, shotcrete has shown strong vitality in the field of construction engineering with its simple process, unique effect, economical cost and wide use, and is widely used It is used in road and railway, water conservancy and hydropower, underground mining, slope support and tunnel construction. Accelerator, as one of the most important admixtures in shotcrete, can promote the rapid setting and harde...

AI Technical Summary

Problems solved by technology

Therefore, the innovative use of molecular design synthesis routes to independently prepare carboxyammonia organic complexing agents containing a large number of amino groups and carboxyl groups can not only complex a large number of aluminum ions to achieve long-term stable existence of high aluminum ion concentration solutions, but its special molecular structure It can also promote higher early strength growth of cement-based materials, and is conducive to industrialization and production applications. There are no reports on this aspect at home and abroad.

Images