Synthetic Naphthalene Superplasticizer And Performance Study

Naphthalene superplasticizer is the earliest use of superplasticizer,with a high water reducing agent rate,the appropriate air volume,and will not affect the concrete setting time,can significantly improve the mechanical properties of concrete,still occupy the larger part of the market.Naphthalene superplasticizer low cost optimization can produce a comprehensive utilization of limited resources,the maximum utilization of raw materials also meet the concept of green chemistry,but also reduce the cost of production effective way.In this paper,the synthesis of naphthalene superplasticizer was studied and using recycle naphthalene instead of industrial naphthalene.The performance of naphthalene series water reducing agent and cement adaptability were studied.The results are divided into the following aspects:(1)Based on the modern production process synthesis and optimization of naphthalene superplasticizer technology,result of the ratio of naphthalene to sulfuric acid is 1:1.4,the sulfonation temperature is 160~165 ?,the ratio of naphthalene to formaldehyde is 1:1.1,acidity of condensation is 29.5 %,the condensation reaction time is 4 h.(2)Based on the optimized synthesis of naphthalene superplasticizer,use of partial recycle naphthalene instead of industrial naphthalene synthesis of naphthalene superplasticizer,and to analyze the effect of partial addition of recycle naphthalene on product performanc.Explored the optimum process of adding recycle naphthalene superplasticizer,result when added 5 % recycle naphthalene,the ratio of naphthalene to sulfuric acid is 1:1.4,the ratio of naphthalene to formaldehyde is 1:1,and the condensation time is 4 h.The performance of the new product is tested by testing the fluidity of the cement paste,result of fluidity of cement paste and mortaris is between240 cm and 250 cm.Measured the maximum adsorption capacity of the naphthalene superplasticizer on the surface of cement particles by ultraviolet spectrophotometry,Optimal amount corresponding to 1 % by mass of the cement.Test the value of the Zeta potential applied to the product slurry were-45.7,-47.8,-47.7,-48.3 mV,applied to verify the product slurry dispersibility strong.(3)A new idea to improved performancenaphthalene superplasticizer disadvantage of poor retention,the results of the fluidity of cement paste is 256 cm and 30 min after maintaining paste fluidity value 200 cm,have improved significantly Compared with the alkaloid neutralizer,the fluidity of the cement paste was 246 cm and the retention rate of the slurry was 185 cm.In summary the add recycle naphthalene and the addition of control within 5 %will not affect the performance of the product,and reached the comprehensive utilization of resources.The use of concentrated sodium hydroxide solution and urea neutralized water reducing agent mother liquor can significantly enhance the cement paste fluidity and mobility retention.