Surfactants for Emulsion Polymers

The terminology, surfactant is a connected word, appropriately derived from surface-active agent.  While used in an extensive range of industries, this blog post will focus on the use of surfactants in the CASE industry segment, where our products are applied in emulsion polymerizations and as stabilizers, dispersants, wetting agents and foam modifiers.  The main functions of surfactants in water-based CASE applications are to emulsify water-insoluble, hydrophobic monomers to facilitate polymerizations in an emulsion state, and to stabilized suspensions of the resulting synthetic polymers so they can be stored, formulated and subjected to shear forces.

The process for creating micelles for monomer polymerizations is depicted below.

When used at low levels, our surfactant types have a profound effect on the properties and performance of the resulting emulsion polymer system.  The optimization of surfactant selection in CASE applications is therefore critically important.   Gantrade and Tiarco offer a diverse range of surfactant compositions and expertise to assist in meeting the requirements of most emulsion polymer applications.   

Types of Surfactants

Surfactants are classified into ionic and non-ionic surfactant types.  Ionic surfactants are classified by the charge on their polar head-groups and include both anionic (negative charge) and cationic (positive charge) surfactants.  The non-polar hydrophobic tail is typically a long-chain hydrocarbon, often derived from natural products such as fatty acids and alcohols.  The largest category is anionic surfactants, which dissociate in water into negatively charged head-groups.  Examples of anionic surfactants include sulfates (-SO₄-), sulfonates (-SO₃-) and carboxylates (-CO₂-). The counter ions are usually ammonium, sodium, or potassium cations.  Conversely, cationic surfactants dissociate in water to positively charges head-groups such as quarternary ammonium salts (-R’N⁺R₃-).  Cationic surfactants are higher in cost than the anionic families. Amphoteric surfactants have a dual charge, both positive and negative, on the head position of a hydrophobic molecule end, such as sulfo-betaines (-N⁺R₂-R’SO₃-). The positive and negative charges neutralize each other creating a net zero charge.

In emulsion polymerization, selection of the correct surfactant type is critical. The surfactant must enable a fast rate of polymerization, minimize coagulum in the process, control viscosity during polymerization and contribute to the performance of the final polymer including stability, gloss, physical properties and water resistance. Anionic surfactants are the preferred type of surfactant, with lauryl (dodecyl) sulfates and alpha-olefin sulfonates being among the common and economical.

The Gantrade-Tiarco Value Proposition for Surfactants

Gantrade and Tiarco-RST have teamed up to offer the emulsion polymer industry a broad portfolio of monomers, surfactants, dispersants, rheology modifiers, specialty chemicals, and industry-leading expertise.  With over four decades of supplying the CASE industry segment, Gantrade and Tiarco offer a wealth of experience and expertise to create real business value to our customers. Our combined resources and product lines allow us to rapidly respond to needs and to help position customers in future markets.

Tiarco’s surfactants’ portfolio has a product for a wide range of applications in the emulsion polymerization, paint & coatings, adhesives & sealants, inks and related applications. The emulsion polymer experts and chemists at Tiarco are always available to assist customers with any formulation challenges and new product developments. Combining technologies from across their leading-edge chemistry portfolios can offer products with distinctive performance properties.

Tiarco employs a unique sulfation technology based on chlorosulfonic acid (CSA).  CSA is reacted with mid-cut fatty alcohols from palm and natural oils to produce a wide variety of surfactant types.  This environmentally friendly advanced manufacturing technology yields higher quality sulfated surfactants, with excellent consistency and minimal waste and clean-up requirements.  The CSA sulfation technology enables short turn-around times and greater flexibility in manufacturing.  Accordingly, Tiarco can custom synthesize or blend a wide variety of unique formulations to meet your special requirements, within strict quality limits.  Production capacities span small and large quantities.

Products are supplied as either “neat” compositions or specialty blends for performance enhancing applications, as follows:

• Anionic Surfactants  Ammonium and sodium lauryl/laureth sulfates, derived from fatty alcohols using the CSA method.  Alkyl Sulfates, Alkyl Ether Sulfates and Alpha Olefin Sulfates.
• Amine Oxides  Lauramine oxides derived from natural feedstocks.
• Alkanolamides  Coco/lauramide diethanol amines typically used in specialty blends.
• Amphoteric Surfactants  Alkyl betaines and alkyl sultanes.  Charge is dependent on the pH.
• Specialty Blends  Anionic surfactants blended with other surfactant types.

Amphoteric Surfactants

Amphoteric surfactants contain both a positive and a negative charge on their polar head-groups. The positive and negative charges neutralize each other creating a net-zero charge.  The pH of the emulsion will control the functional charge of the head position. In acidic solutions, amphoteric surfactants will exhibit a positive charge, similar to cationic surfactants. In basic solutions, amphoterics develop a negative charge, similar to anionic surfactants.  Amphoterics exhibit excellent compatibility with other surfactants.

The range of amphoteric surfactants we offer are summarized below.

• Alkyl Betaines
• Alkyl Sultanes
• Alkanolamides
• Concentrates

Specialty Blends

Surfactant blends, specially formulated to meet the diverse coating needs of a broad range of latex applications, are effective with SBR, VAE, EVA, Acrylics, Vinyl Acrylics, SBR-X (carboxylated), and many other aqueous emulsion dispersions. These blends are compatible with most fillers, thickeners, and auxiliaries. Designed to be both cost-effective and efficient at low usage levels, these products provide the formulator with a full range of coating capabilities.

The table below lists some of the specialty blends available from Gantrade and our partner, Tiarco.

With these offerings, you can see that Gantrade-Tarco specialize in the synthesis and manufacturing of both anionic and amphoteric surfactants. In addition, we can sulfate most organic alcohols to meet specific needs. 

Partner for Your Success

Together, Gantrade and Tiarco offer a broad portfolio of monomers, intermediates, polymers, crosslinking chemistries, surfactants, rheology modifiers, dispersants, and related products that help to advance performance dimensions in emulsion-based paints and coatings, adhesives and sealants, inks and more.  Our combined teams and capabilities are always available to assist customers with formulation challenges and to tailor new products that can offer distinctive performance advantages. Whatever your specialty requirements, we welcome the opportunity to work jointly to enhance the performance of your products. Contact Gantrade today to get started.