Sodium naphthalene sulfonate formaldehyde or SNF is widely used in the construction industry. The chemical does have other applications. This article will help you understand the SNFs various applications, the benefits of using it, and the technical specifications of using it.
The Asia-Pacific region uses about 50% of the global supply of the compound. This trend is likely to continue until the end of 2023. Its wide applications make it necessary to understand the applications of SNF.
What Are Its Primary Uses?
SNF is most commonly used in construction as anionic surfactant and accelerator. Apart from this, it is used in agrochemicals to manufacture uniform dispersed suspension. In the rubber industry, the chemical is used as a dispersing agent for pigments and fillers and an anti-coagulating agent in synthetic rubber polymerisation.
SNF is mixed with gypsum to make a water-reducing Stucco mix. It is highly soluble in ethylene and diethylene glycol, glycerol, water, and to a certain level in alcohol. It does not dissolve in organic solvents.
What Are the Benefits of Using?
Mixing sodium naphthalene sulfonate formaldehyde in cement gives it a higher dispersibility, lowers foaming, reduced water usage, and strength. It also helps accelerate the construction process, thus saving cost and time. SNF has non-eroding qualities that make it compatible with reinforcement bars.
These qualities place it in a prime position for construction, especially public projects like bridges, highways, and tunnels. SNF, depending on the chemical used, can either accelerate or retard the hardening of concrete.
Retarding Agent
The retarding qualities of the SNF admixture help keep concrete in its freshly mixed form longer. The delayed hardening allows mixing large batches, resulting in saving time of mixing small batches of concrete. This property allows a delay of at least one hour in hardening, thus allowing for specialized architectural surface finish.
Superplasticizers
Zhang et al. (2007) studied the dispersing mechanism of SS and concluded that this water reducer is even better than the traditional naphthalene-sulfonated formaldehyde condensates (FDN). This would be because of its better dispersing capacity and stability. The dispersion capacity of SS is obtained from steric hindrance effects. The dispersions stabilized by steric hindrance, in this case by SS, have a good fluidity at low adsorption amounts (5 mg/g) and a high stability.
Adding SNF to the concrete mix can reduce the use of water by 12% to 30%. It also results in higher strength, heavy reinforcement, and accelerated setting time. The savings in time for drying can be up to one hour earlier. Using SNF is known to enhance concrete strength by 50% to 75%.
Antifreeze
SNF antifreeze is made with ethylene glycol. It gives the mixture robust protection against frost, over-heating, and corrosion.
Free-Flow Concrete
This light brown powder helps create a free-flowing concrete mixture that is easily pumpable, pourable, movable, and malleable. Because hardening can be delayed, this process allows for crafting surface shapes of varying finish.
Technical Specifications
By mixing 0.5% to 1% of the SNF can result in a 20% to 30% reduction rate. It helps save on cement by up to 20%. Using 0.7% SNF in solid form can help elevate the slump constant above 10 cm.
Sodium naphthalene sulfonate formaldehyde offers antifreeze, accelerant, and retarder properties for many industries. As an admixture in the construction process, it can help reduce cost, time, and allows a degree of flexibility. The compound’s many properties make it equally ideal for large public construction projects to small houses. SNF can form a good base for other cement admixes.
