Preparation method of cellulose ether with high suspension, strong rheology and bleeding prevention

Abstract

The invention belongs to the technical field of modified synthesis of cellulose ether, and particularly discloses a preparation method of high-suspension, strong-rheology and anti-bleeding cellulose ether. The method comprises the following steps: synthesizing and preparing cellulose ether by a universal process flow; during subsequent synthesis, adding a water-soluble rheological polymerization modification monomer with a proper concentration ratio; and carrying out substitution treatment under the conditions of a proper catalyst and a water bath temperature to finally obtain the modified cellulose ether. According to the invention, the cellulose ether has the advantages of high water-retaining property, low viscosity, high suspension, strong rheology, sedimentation resistance and the like, is used in self-leveling mortar, grouting materials, grouting agents, high-performance concrete and other mortars, can ensure high fluidity and pumpability, avoid the phenomena of sand setting, bleeding, layering, segregation and the like during construction, maintain the cohesive viscosity of pouring self-leveling, grouting materials and concrete and ensure the uniformity and the stability ofhardened mortar, and avoids the quality problem.

Description

technical field [0001] The invention belongs to the technical field of modification and synthesis of cellulose ether, and in particular relates to a preparation method of cellulose ether with high suspension, strong rheology and anti-bleeding. Background technique [0002] In mortar and concrete, cellulose ether, as an essential additive, is widely used in mortar and concrete due to its excellent water retention and thickening properties. In mortar and concrete, cellulose ether can not only play a role in water retention The thickening effect can also prevent the mortar from segregating, settling, and bleeding, and improve the construction and workability of the mortar. For products with relatively high fluidity requirements, such as self-leveling, grouting materials, grouting agents, and high-performance concrete, etc., Cellulose ether with low viscosity is used, but self-leveling, grouting material, grouting agent, and high-performance concrete products are often used duri...

AI Technical Summary

Problems solved by technology

[0002] In mortar and concrete, cellulose ether, as an essential additive, is widely used in mortar and concrete due to its excellent water retention and thickening properties. In mortar and concrete, cellulose ether can not only play a role in water retention The thickening effect can also prevent the mortar from segregating, settling, and bleeding, and improve the construction and workability of the mortar. For products with relatively high fluidity requirements, such as self-leveling, grouting materials, grouting agents, and high-performance concrete, etc., Cellulose ether with low viscosity is used, but self-leveling, grouting material, grouting agent, and high-performance concrete products are often used during construction due to the use of coarse aggregate and high fluidity requirements. The coarse aggregate sinks, the fine aggregate floats up, the slurry segregates and bleeds, and the upper and lower layers are separated. After the cement is hardened, the surface strength is pulverized, and the surface and internal strength are inconsistent, which seriously reduces the product performance and affects the performance of mortar, especially concrete. Strength, stability and durability will cause great safety hazards to engineering quality; currently, low-viscosity cellulose ether has limited thickening effect due to its low viscosity, and cannot effectively improve this problem, while high-viscosity cellulose ether has obvious However, due to excessive viscosity, self-leveling, grouting material, grouting agent and high-performance concrete will not flow, which will affect its pumpability and leveling performance. Therefore, low-viscosity cellulose ethers should be flowed Modified to improve self-leveling, grouting, bleeding, delamination and other problems, so that these high-flow dynamic mortar and concrete can have excellent flow performance, and will not segregate, sink, Avoiding quality problems during use needs to be resolved urgently

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