Copolymerization Preparation Of Lignosulfonate Superplasticizer

The raw materials of lignosulfonate superplasticizer were paper pulp waste liquid and the production process is simple, so it was an environmentally friendly products. Because of the limitations of the basic properties of lignosulfonate superplasticizer, the applications were limited in high performance concrete. In order to search for superplasticizer, we have synthesized a series of superplasticizer by condensation reaction of lignin sulfonate, phenol, sulfanilic acid, formaldehyde, sodium sulfite and acetone.Single factor experiments and orthogonal experimental results show that the optimum experimental conditions of synthesizing amino acid superplasticizer:phenol and sulfanilic acid molar ratio of 1.5:1, the initial reaction system pH of 8.5, condensation time of 5h, (phenol+on amino acid) and formaldehyde molar ratio of 1.25, formaldehyde dropping time of 60min, the temperature of dropping formaldehyde was 70℃, condensation temperature of 95℃. using the above conditions we Synthesized a series of superplasticizer with different contents of lignin sulfonate. Byζpotential, the net fluidity, fluidity and plastic sand bleeding rate superplasticizers analysis, the best modified products when the content of the lignin sodium was 30wt%.Single factor experiments and orthogonal experimental results show that aliphatic superplasticizer optimum experimental conditions:sulfonation rate of 0.55, formaldehyde and acetone molar ratio of 2.0, sulfonation time of 10min, sulfonation temperature of 55℃, formaldehyde dropping time of 45min, the condensation temperature of 90℃, the condensation time was 2.5h.Single factor experiments and orthogonal experimental results show that the copolymerization of aliphatic lignin sulfonate superplasticizer optimum experimental conditions: sodium and aliphatic wood mass ratio 1:9, the quality ratio of formaldehyde and aliphatic was 0.4:1, the condensation temperature of 95℃, and the condensation reaction time was 2h.The synthesis of lignin sulfonate and aliphatic compound superplasticizer physical samples and aliphatic lignin sulfonate superplasticizer copolymerization performance comparison analysis, through adsorption, fluidity of cement paste and by the time the loss Determination ofζpotential obtained, lignin sulfonate superplasticizer copolymerization of aliphatic performance is significantly better than the former.