Sulfonated alkyl naphthalene formaldehyd

There are three main uses for naphthalene sulfonic acid derivatives (75—79) as naphthalenic tanning material alkyl naphthalene sulfonates for industrial appHcations as nondetergent wetting agents and as dye intermediates. Consumption of naphthalene sulfonates as surfactants accounts for a large portion of usage. Naphthalene sulfonate—formaldehyde condensates are also used as concrete additives to enhance flow properties. Demand for naphthalene sulfonates in surfactants and dispersent appHcations, particularly in concrete, was expected to increase into the twenty-first century. Consumption as of 1995 was 16 x 10 kg/yr. 

Manufacturing procedures for producing dye dispersions are generally not disclosed. The principal dispersants in use include long-chain alkyl sulfates, alkaryl sulfonates, fatty amine—ethylene oxide condensates, fatty alcohol—ethylene oxide condensates, naphthalene—formaldehyde—sulfuric acid condensates, and the lignin sulfonic acids. 

Melamine formaldehyde sulfonate and naphthalene sulfonates are added to concrete to plasticize the mix. A plasticizer in concrete technology is a cement-dispersing agent. Other polymers can be added to cement mortars/concretes to improve flexibility and reduce permeability to water, e.g., styrene butadiene rubber (SBR) emulsions to give air entrainment for freeze-thaw resistance, e.g., alkyl sulfonates or to thixotropize a mix, e.g., polyacrylamide. 

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