Styrene/Acrylates Copolymer is a polymer of styrene and a monomer,  a polymer formed from the copolymerization of styrene and acrylate monomers. It's commonly used in cosmetics and personal care products as a thickening agent, opacifying agent, emulsifying agent, and emulsion stabilizer.

The name describes the structure of the molecule

• "Styrene" refers to the styrene monomer, a colorless liquid used in the production of various polymers. 
• "Acrylates" refers to monomers derived from acrylic acid. 
• "Copolymer" indicates that the material is formed from the polymerization of two different monomers.

Description of raw materials used in production

The primary raw materials are styrene and acrylate monomers. These monomers are then polymerized together to form the copolymer.

Synthesis process

• Preparation - Styrene and acrylate monomers are mixed in controlled proportions.
• Initiation - An initiator is added to start the polymerization reaction.
• Chain addition - The ingredients react at a specific temperature for a certain period, allowing the monomers to bond together and form polymer chains.
• Termination - The reaction is stopped once the desired degree of polymerization is reached.
• Purification - The copolymer is purified from any impurities.
• Packaging - The copolymer is then packaged for sale or used as an ingredient in various products.

It appears as a white liquid.

Substances used in production:

Styrene, acrylic acid, methacrylic acid or their simple esters.

What it is used for and where

Cosmetics

Film-forming agent. It produces a continuous ultra-thin film with an optimal balance of cohesion, adhesion and stickiness on the skin or hair to counteract or limit damage from external phenomena such as chemicals, UV rays and pollution.

Opacifying agent. It is useful into formulations that may be translucent or transparent to make them opaque and less permeable to light.

Applications

• Cosmetics and Skin Care Products - Used as a film-forming agent and thickener in cosmetics, such as nail polishes, creams, and lotions.
• Hair Care Products - Used in shampoos and conditioners to enhance consistency and viscosity.
• Cleaning Products - Added to detergents and cleaning products to enhance their consistency and cleaning properties.
• Construction and Industrial Materials - Used as a component in mortars, adhesives, and other construction materials.
• Paints and Coatings - Employed to enhance the adhesion properties, durability, and appearance of paints and coatings.

CAS      27306-39-4   25034-86-0   25085-34-1   9010-92-8 

Safety

Styrene is a fat-soluble organic molecule obtained from the Friedel-Crafts reaction between benzene and ethylene. It is a residual monomer that can be absorbed through the skin. It can cause neurotoxic effects.

Trade name:

• OPULYN™ 302B Opacifier
• ACUDYNE™ Shine Polymer
• ACUDYNE™ Bold Polymer
• Sunspheres™
• Syntran® 5903
• Syntran® 5905

References_____________________________________________________________________

Kraeling, M. E., & Bronaugh, R. L. (2005). In vitro percutaneous absorption of acrylamide and styrene from cosmetic vehicles through fuzzy rat and human skin. Cutaneous and Ocular Toxicology, 24(1), 65-79.

Abstract. Acrylamide (ACR) and styrene (STY) are residual monomers that remain as impurities in polymers used in hair, nail, and skin care products. These residual monomers may be substantially absorbed through skin. Acrylamide is known to be a neurotoxin in humans and a carcinogen in animals, while styrene has been reported to cause neurotoxic effects in humans and animals and carcinogenic effects in rodents. Therefore, studies were conducted to measure the extent of ACR and STY absorption in fuzzy rat and human skin relevant to exposures from personal care products using in vitro diffusion cell techniques. [14C]-ACR was applied to skin in flow through diffusion cells for 24 h using an oil-in-water (O/W) emulsion at doses of 2.2 and 13.3 μg/cm2 (fuzzy rat skin) and 0.2, 2.2, and 13.3 μg/cm2 (human skin). [14C]-ACR was also applied to human skin using a 2% polyacrylamide gel cream at a dose of 0.3 μg/cm2. [14C]-STY was applied to fuzzy rat and human skin using the O/W emulsion at a dose of 4.1 μg/cm2. The total amount of ACR or STY that penetrated into skin layers and receptor fluid at the end of the 24 h experiment was measured and expressed as the percent of applied dose penetrated. Absorption was defined as the amount of ACR or STY absorbed into the receptor fluid. At the both the 2.2 and 13.3 μg/cm2 dose levels using the O/W emulsion, ACR was rapidly absorbed through both fuzzy rat and human skin, with peak absorption occurring at 6 h. For fuzzy rat skin, total ACR penetrated was 52.9±1.3% at the lower dose level and 49.7±2.4% at the higher dose level. For human skin, total ACR penetrated was very similar with and 48.9±1.4% (0.2 μg/cm2 dose level), 49.5±4.4% (2.2 μg/cm2 dose level), and 60.6±12.1% (13.3 μg/cm2 dose level). The total ACR penetrated was reduced to 38.7±11.9% when ACR was applied using the 2% polyacrylamide gel cream (0.3 μg/cm2 dose level). The amounts of total STY that penetrated into fuzzy rat and human skin using the O/W emulsion vehicle were identical at 1.3% (4.1 μg/cm2 dose level). Although absorption of STY was relatively low, it was nevertheless rapid with peak absorption occurring at 6 h. Approximately 84–92% of the total ACR or STY penetrated was absorbed into the receptor fluid while only 8–16% of the total ACR or STY penetrated remained in the skin at 24 h. For these monomers, rodent skin satisfactorily simulated the barrier properties of human skin; there was no significant difference in ACR and STY absorption between fuzzy rat and human skin.

Bernauer, U., Bodin, L., Chaudry, Q., Coenraads, P. J., Dusinka, M., Gaffet, E., ... & Wijnhoven, S. (2019). Opinion on Styrene/Acrylates copolymer (nano) and Sodium styrene/Acrylates copolymer (nano) SCCS/1595/18–Final (Publications Office of the European Union, Luxembourg, Luxembourg (23 pages)(2019)-ISSN: 1831-4767-ISBN: 978-92-76-00235-2.