Method for synthesizing polyethylene glycol monomethyl ethermethacrylic acid esters by nitrogen with water

Abstract

The present invention relates to a method of synthesizing methoxypolyethylene glycols methacrylate with water-carrying nitrogen; and belongs to the technical field of ester compound synthesis in organic chemistry, taking methyl poly glycol and methacrylate as raw materials, toluenesulfonic acid or concentrate sulfuric acid as catalysts, phenothiazine and hydroquinone as polymerization inhibitor to carry esterification reaction in which water-carrying nitrogen is communicated to produce methoxypolyethylene glycols methacrylate; the mole ratio of methoxypolyethylene glycols to methacrylate can be 1.0:1.5-8.0. The present invention adopts the pattern of water-carrying communication to yield methoxypolyethylene glycols methacrylate, which can effectively reducing the cost; at the same time, catalyst and polymerization inhibitor are reasonably selected for the reaction of esterification, the reacting conditions are moderate, without toxic solvent as water-carrying agent; thereby being friendly to the environment.

Description

technical field [0001] The invention relates to a method for synthesizing polyethylene glycol monomethyl ether methacrylate with nitrogen gas and hydration, and belongs to the technical field of synthesis of ester compounds in organic chemistry. Background technique [0002] Polyethylene glycol monomethyl ether methacrylate is the active macromonomer of polycarboxylate water reducers, and polycarboxylate water reducers are ordinary water reducers represented by wood calcium and naphthalene series. The third generation of high-performance water reducer developed after the representative high-efficiency water reducer. This kind of water reducing agent has low dosage, high water reducing rate, no segregation, no bleeding, good concrete slump performance, good compatibility with cement, admixtures and other admixtures; it can effectively reduce the early thermal insulation of concrete Temperature rise and temperature cracks of mass concrete; the degree of freedom in molecular s...

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Problems solved by technology

The synthesis method of polycarboxylate water reducer is mainly prepared by polymerization of polyethylene glycol monomethyl ether methacrylate and other active monomers, but the synthesis method of polyethylene glycol monomethyl ether methacrylate is reported Fewer, and the method of report mostly also is to adopt and add poisonous solvent such as benzene, toluene, hexanaphthene etc. in esterification reaction process as water solvent, as Japanese patent JP2003327689 proposes to use polyethylene glycol monomethyl ether (EO= 25) and methacrylic acid as the reaction raw material, take cyclohexane as the solvent with water, carry out esterification reaction, and finally cyclohexane is removed by distillation to obtain polyethylene glycol monomethyl ether methacrylate, not only The production process is cumbersome, the cost is high, and it is harmful to the environment

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