What are Silicones Emulsions?
Silicone emulsions are silicone oils dispersed in an aqueous system. Emulsions are ideal for surface treatments, being easy to apply, and are simple to prepare.
The high viscosity of certain silicone oils can be effectively reduced by their emulsification. The aim of silicone emulsion formulation is to improve & facilitate the product's presentation, processing and efficiency. The various components in emulsions (the carrier, typically water, the silicone, and its emulsifiers) do not react with one another, nor do they react with the surfaces that they are applied to. Emulsions are therefore ideal for surface treatment applications since they are less viscous than the oils they are delivering. Their other advantage is that preparation is simple: Polydimethylsiloxane (PDMS) oils are dispersed (emulsified) in an aqueous system (and they are particularly practical since they are easy and safe for the end user to handle, apply and dilute.
Silicone emulsions properties
Silicone emulsions are insoluble silicones evenly dispersed in water with the aid of an emulsifying surfactant. They can be divided into three groups, depending on the type of emulsifier system used, i.e. they can be anionic, cationic and non-ionic. Most emulsions are non-ionic, making them compatible with either of the other two systems but, depending on the application, cationic or anionic emulsions may be preferable.
The physical characteristics of these emulsions can be altered by using different polymers to modify their viscosity if needed. High percentage solid versions supplied as concentrates, for dilution with water prior to use, reduce transport costs and the space required for their storage.
Silicone fluids are commonly used in the form of aqueous emulsions, which may be further diluted with water. A distinction is made between opaque (i.e. milky) macro-emulsions with particle sizes from 100 nm to several µm and clear or opalescent micro-emulsions, with particle sizes below 100 nm.
Silicone emulsions are easy to use and apply, are more environmentally friendly than solvent-based systems and, being water-based do not generate additional health hazards in the workplace. For example, baking and cooking paper manufacturers use emulsion silicones for coatings to replace other coating types including solvent containing formulations. The uniform distribution of a thin layer of silicone onto substrates gives efficient non-stick performance improving hygiene, reducing food waste and aiding efficiency in both industrial and home cooking applications. Silicone emulsion-based food papers can be used in all types of cooking, including baking, pan-frying and steaming
Emulsion silicones are used in:
- Rubber and plastics as release agents and lubricants
- Food trays and plastic serving dishes as release agents
- Car polishes and household cleaners to improve protection, resistance, gloss and spreadability
- Textile finishing to enhance feel, water repellency and reduce the need for ironing
- Perlite, vermiculite and clay and other building materials to improve water repellency and protect against dampness
- Printing and papermaking for lubrication and as an antistatic agent.
Emulsion is a category of product form. Emulsion is a formulation of silicones in aqueous form.
Emulsions are dispersions of one liquid in another liquid, generally stabilized by an emulsifier, both liquids being non-miscible. In the specific case of silicone emulsions, silicones are dispersed as droplets in a water continuous medium.
Water-based, water-dilutable, stable, easy to use, environmentally-friendly, safe in storage, transportation and application. Enable small and uniform quantity of coating on the substrate. Sensitive to chemical, thermal & mechanical environment, cannot be applied in a system which is not compatible with water.
Silicone, Emulsifier / surfactant, Water + other additives (rheological agents, preservatives, …)
Dispersion of the silicone phase into the aqueous phase under shear, either by direct process or by phase-inversion process
Release coating, textile & tissue softener, antifoams, water repellents & paints, lubrication & demoulding, personal care
Beyond the use of silicone emulsions as process facilitators in the industries cited in our summary table above, they are also used as formulation ingredients in cosmetics and body care products, in particular in shampoos, where silicone emulsions give hair a silky softness, making it easier to comb and untangle after washing.
Five places you did not expect to find silicone as a product-enhancing material
Most of us like to use shampoo in the shower and sunscreen on the beach, and for many consumers daily use of deodorants is a must. Sounds familiar? Then the probability is high that you surround yourself with silicone on a regular basis
Every year, hundreds of thousands of personal care and cosmetic products are launched worldwide. A high percentage of these use silicones in their formulations to enhance their efficacy in a wide variety of applications.
Elkem has a long history in delivering sustainable silicone products to the personal care and cosmetic products industries, leveraging on more than 70 years of the proven performance of silicones to help our customers delivering their potential.
What are silicones?
Silicones are inert synthetic compounds that come in a variety of forms (including oil, rubber and resin). Typically, heat-resistant and rubber-like, they are present in sealants, adhesives, lubricants, medical applications, personal care products, cookware and insulation. Silicones are polymers that contain silicon, combined with carbon, hydrogen and oxygen and, in some cases, other elements.
Here are five places where you perhaps did not expect to find silicone as a product-enhancing material:
- In hair care products (shampoo and conditioners, shine sprays and frizz serums, etc.) they provide superior conditioning, add shine, control frizz, and provide easy detangling and protection from further damage.
- In skin care products (creams, lotions, and anti-aging serums, acne treatments, etc.) they add a silky-smooth feel to the skin and mask fine lines to deliver the attributes of a healthier and more youthful appearance.
- In sunscreen products (skin creams, lotions and foundations with sun protection factor, SPF) they reduce the tackiness of organic sunscreens, boost the SPF and increase the water repellency
- In color cosmetics (lipsticks and lip colors, foundations, eye shadows, primers, powders, etc.) they impart color intensity, uniformity, non-transfer, luminosity and comfort with long lasting performance
- In APDEO products (anti-perspirant and deodorant gels, sticks, roll-ons and aerosols) they reduce the whiteness and the tack of the antiperspirant salt, improve skin feel and provide easy glide.
Elkem has developed several product brands focusing on innovation and technologies to help customers innovate and differentiate.