Preparation method of a temperature-sensitive chelating gel concrete internal curing agent

Abstract

The invention discloses a method for preparing a temperature-sensitive chelating gel concrete internal curing agent. The method steps are as follows: raw materials are selected: 10-25 parts of temperature-sensitive macromolecular monomers, 5-15 parts of chelating functional monomers, 20~45 parts of nonionic monomer, 25~40 parts of anionic monomer, 1~10 parts of crosslinking agent, 1~10 parts of initiator, 10~25 parts of sodium hydroxide; stir and dissolve the anionic monomer and add hydrogen to oxidize Adjust the sodium to neutral, add the chelating functional monomer and non-ionic monomer in sequence and stir to dissolve, add the temperature-sensitive macromer while stirring, add the initiator and cross-linking agent in sequence after passing nitrogen for 30 minutes, and continue to pass nitrogen for 30‑ 60min, sealed, kept at 20-50°C for 8-24h; dried, pulverized, and sieved. The internal curing agent of the invention can adjust and control the release rate of water according to the temperature change in the cement hydration process, has moderate water absorption rate and low water absorption multiple, and can effectively improve the strength of concrete.

Description

technical field [0001] The invention belongs to the technical field of building material admixtures, and in particular relates to a preparation method of a temperature-sensitive chelating gel concrete internal curing agent. Background technique [0002] In recent years, with the continuous expansion of the scale of civil engineering and the continuous improvement of the level of science and technology, some important buildings with high-rise and long-span and special functional requirements have emerged continuously. The main trend, the use of low water-binder ratio, mineral admixtures, chemical admixtures, etc. are the main means to achieve the above properties. The rapid growth of lower water bands from shrinkage is the main cause of early cracking in high-strength concrete. In addition, due to the dense structure and low permeability of high-strength concrete and self-compacting concrete, conventional external water curing, continuous spraying, spraying curing agents, et...

AI Technical Summary

Problems solved by technology

At present, the water-absorbing resins on the market are generally synthesized from acrylic acid. This type of product has strong water absorption capacity, too fast water absorption rate, and poor water release performance. When used as an internal curing agent, it absorbs too much mixing water in the early stage, which significantly reduces the work of concrete. Performance, can not meet the actual construction requirements, thereby limiting the application of superabsorbent resin in the field of concrete admixture

Images