AEROSIL 200

AEROSIL 200

Cas no: 7631-86-9; 112945-52-5
EC no: 231-545-4

Synonyms:

Silicon dioxide; silicium dioxide; colloidal anhydrous silica; celite; Aerosil 200; Quartz; Silica; Silicic oxide; Silicon(IV) oxide; Crystalline silica; Pure Silica; Silicea; Silica sand; Silica; SILICON DIOXIDE; Quartz; 7631-86-9; Cristobalite; Dioxosilane; Diatomaceous earth; Tridymite; Sand; Infusorial earth; Silicic anhydride; Diatomaceous silica; Dicalite; Crystalline silica; Silica, amorphous; Christensenite; Crystoballite; Siliceous earth; Silicon oxide; Amorphous silica; QUARTZ (SIO2); Silica, colloidal;61790-53-2; Silicon(IV) oxide; Amethyst; Aquafil; Carplex; Cataloid; Chalcedony; Crysvarl; Diatomite; Metacristobalite; alpha-Quartz; Cristobalite (SiO2); Fossil flour; Fused silica; hydrophilic fumed silica; hydrophobic fumed silica; Quartz dust; Quartz glass; Quartz sand; Quartz silica; Rock crystal;
Rose quartz; Silica dust; White carbon; Silica particles; Silicone dioxide; Cristobalite dust; SILICA, VITREOUS; alpha-Cristobalite; alpha-Crystobalite; Calcined diatomite; Colloidal silicon dioxide; Siliceous earth, purified; Pigment White 27; Amorphous silica gel; Silicon dioxide (amorphous); Aerosil 200; Amorphous silica dust; silanedione; Silicon dioxide, fumed; Silica, amorphous fused; Silica slurry; Tridymite dust; Silica, amorphous, fumed; Pyrogenic colloidal silica; Synthetic amorphous silica; Hydrophobic silica; Calcined diatomaceous earth;
Crystallized silicon dioxide; Diatomaceous earth, calcined; Silicon oxide, di- (sand); Cristobalite asbestos; Silica, amorphous, fumed; Fumed silica, crystalline-free;  Dimethyl siloxanes and silicones; Aerosil 200; Fumed synthetic amorphous silica; Silica, crystalline - tridymite; Synthetic amorphous silica, fumed; Silicon dioxide, chemically prepared; EINECS 231-545-4; Silica, crystalline quartz; Silicon dioxide, colloidal; Silica, crystalline, quartz; Silica, crystalline: quartz; [SiO2]; Silica, crystalline - fused;  Silica, crystalline tridymite; Silica, crystalline - quartz; Quartz [Silica, crystalline]; Silica flour (powdered crystalline silica); Silica, crystalline: tridymite; Silicondioxide;
Tridymite [Silica, crystalline]; Celite; Silica, crystalline: cristobalite; Silica, crystalline - cristobalite; Cristobalite [Silica, crystalline]; Sand, Sea; Amorphous silica: Pyrogenic (fumed); silica gel desiccant; Silica vitreous; Aerosil 200; Chromosorb P; Tridymite (SiO2); beta-Quartz; Fumed silica; Fused quartz; Quartz-beta; Silica glass; Amorphous quartz;Silica gel, spherical; Silica, fused; Microcrystalline quartz; Cryptocrystalline quartz; Silicon dioxide, 99.998%; Silica, amorphous, fused; quartz-glass; Silicom dioxide; silica-gel; Silicon dioxide, amorphous gel; Fused-silica; Silica,fumed; silicium dioxide; silica-; Silicon di-oxide; Silica, tridymite; Diatomaceous earth, flux-calcined; Silica, fumed, hydrophobic; Silica, hydrate(8CI,9CI); Silicon(IV) oxide (SiO2); Silica, mesoporous

AEROSIL 200

Fumed silica has a very strong thickening effect. Primary particle size is 5–50 nm. The particles are non-porous and have a surface area of 50–600 m2/g. The density is 160–190 kg/m3.

AEROSIL 200 is a hydrophilic fumed silica with a specific surface area of 200 m2/g. 

Fumed silica is the superfine micro-nano fine chemical product, which is divided into hydrophilic type and hydrophobic type in accordance with their different surface treatments. Its appearance is white powder. Native particle size ranges from 5nm to 40nm, with significant functions of thixotropy, reinforcing, thickening and filling.

Fumed silica is an non-toxic non-harmful material. It is not combustible nor explosive. In fact fumed silica has been applied in cosmetic, food and drugs for years.

Silica is the dioxide form of silicon, SiO2, and occurs mostly as quartz sand, flint, and agate. Silica's powder form is used to manufacture glass, ceramics, etc. SiO2 is the chemical compound silicon dioxide. It is formed when silicon is exposed to oxygen.

Amorphous silica (SiO2) is an inorganic material commonly used in semiconductor circuits to isolate different conducting regions. Due to its mechanical resistance, high dielectric strength, and selectivity for chemical modification, amorphous silica has also become a key material in microelectronics and chromatography.

Silica is mainly soluble under three conditions: highly alkaline such NaOH or KOH; in presence of free fluoride ions; or by complexation with molybdate ions.

Fumed silica serves as a universal thickening agent and an anticaking agent (free-flow agent) in powders. Like silica gel, it serves as a desiccant. It is used in cosmetics for its light-diffusing properties. It is used as a light abrasive, in products like toothpaste.

Chemically, silica is an oxide of silicon, viz., silicon dioxide, and is generally colorless to white and insoluble in water.

Fumed silica is made from flame pyrolysis of silicon tetrachloride or from quartz sand vaporized in a 3000 °C electric arc.

Fumed silica, also known as pyrogenic silica because it is produced in a flame, consists of microscopic droplets of amorphous silica fused into branched, chainlike, three-dimensional secondary particles which then agglomerate into tertiary particles. The resulting powder has an extremely low bulk density and high surface area. Its three-dimensional structure results in viscosity-increasing, thixotropic behavior when used as a thickener or reinforcing filler.

-AEROSIL 200 is an anti-caking, free flowing, gelling, suspending, dispersing and thickening agent.
-AEROSIL 200 hydrophilic fumed silica (a hydrophilic fumed silica with a specific surface) used to convert cosmetic oils into gels with high viscosity. Like silica gel, it has a desiccant feature. It is used in cosmetics for its light reflective properties.
-AEROSIL 200 is used as a mild abrasive in products such as toothpaste. Other uses include silicone elastomer filler and viscosity adjustment in paints, coatings, printing inks, adhesives and unsaturated polyester resins.
-AEROSIL 200 is also used as the core material in the production of vacuum insulated panels.
-AEROSIL 200prevents agglomeration of active ingredients (usually aluminum and zirconium salts (AP salts)) to ensure that they are evenly distributed in a homogeneous structure and have an intense, long-lasting effect.
-It also prevents white residue. 
-AEROSIL 200 is recommended for use in skin care, oral care, hair care (dyes, hair conditioners), make-up (powder, nail polish, lipstick, lip gloss) and antiperspirant deodorants (roll-on) applications.
-AEROSIL 200 has the ability to absorb moisture up to 120% of its own weight. It has a usage rate of 0.2% to 2%. 
-AEROSIL 200 is used as an anti-precipitation of rheology and dixortropy such as liquid systems, binders, polymers. In other words, it has a thickening effect. It is used to reinforce silicone rubber, to correct the free flowability of the powder and the anti-caking characteristics.

While many of the studies on silica have been done on animals, researchers have found no link between the food additive silicon dioxide and increased risk of cancer, organ damage, or death.

Due to Aerosil 200's fineness and thinness, fumed silica can easily become airborne, making it an inhalation risk, capable of causing irritation.

Applications of Aerosil 200

-Paints and coatings
-Unsaturated polyester resins, laminating resins and gel coats
-HTV- and RTV-2K-silicone rubber
-Adhesives and sealants
-Printing inks
-Cable compounds and cable gels
-Plant protection
-Plastics
-Papermaking
-Medicine
-Cosmetics

Fumed silica serves as a universal thickening agent and an anticaking agent (free-flow agent) in powders. Like silica gel, it serves as a desiccant. It is used in cosmetics for its light-diffusing properties. It is used as a light abrasive, in products like toothpaste. Other uses include filler in silicone elastomer and viscosity adjustment in paints, coatings, printing inks, adhesives and unsaturated polyester resins.

It is also used in the production of cat litter box filler and as a core material in the production of vacuum insulated panels. Moreover, Fumed silica nanoparticles can potentially be used as efficient anti-ageing coatings in asphalt pavements.

Properties of Aerosil 200

Rheology and thixotropy control of liquid systems, binders, polymers, etc.
Used as anti-settling, thickening and anti-sagging agent
Reinforcement of HTV- and RTV-2K silicone rubber
Improvement of free flow and anticaking characteristics of powders

Coating formulators can incorporate both hydrophilic and hydrophobic AEROSIL® without difficulty into water-based coatings by using the appropriate dispersion equipment (e.g. a bead or ball mill). The degree of dispersion is a crucial determinant of the efficiency of AEROSIL 200. For AEROSIL 200 to work as effectively as possible, good dispersion is essential.
In pigmented systems, AEROSIL 200 should be dispersed along with the pigments. If AEROSIL® is used in clear coatings, dispersion by the masterbatch process is recommended. For example, an AEROSIL® concentration of 4–8% (relative to the solid binder) has proven satisfactory for dispersion in a bead mill; this allows efficient processing and an optimal degree of dispersion. The masterbatch can then be let down to the final concentration desired.
As a multifunctional additive, AEROSIL 200 can be used in all layers of a coating structure due to its versatile product capabilities:

• Primers
• Fillers
• Base Coats
• Clear Coats
• Top Coats

Extensive testing has shown that adding 0.5 – 1.0 % AEROSIL®, relative to the total coating formulation, is appropriate. These concentrations should be regarded as reference values only, and must be amended if required. The following examples illustrate how AEROSIL 200 can be used in various water-based coating systems.

The rheological properties of paints and coatings can be regulated according to the needs with either hydrophilic or hydrophobic AEROSIL 200 grades. Added amounts of 0.3 - 2.0 %, based on the total formulation, are typical in nearly all solvent and water-based systems, as well as in high-solids coatings. The incorporation of AEROSIL 200 particles into a coating generally produces a pseudoplasticity that is often linked to a thixotropic effect, i.e. a dependence on time. The dependence of the flow behavior of pseudoplastic coating systems on the shear rate guarantees high level application due to the low viscosity at high shear rates.

Especially with spray application, where very high shear forces occur, this low viscosity at application conditions results in the formation of very fine paint droplets, which can be distributed onto a substrate for optimal leveling. The high viscosity of a coating at low shear forces or at rest ensures an increased maximum wet-film thickness by using AEROSIL 200 fumed silica. It also serves to counteract the sedimentation of pigments and fillers. AEROSIL 200 grades are also used successfully to regulate the rheology of special-effect coatings. The fixing of the special effect in metallic base coats and in structural or hammer-finish paints, deserves a special mention here.

One of the most traditional applications of AEROSIL 200 fumed silica in the coatings industry is its use as an anti-settling or suspension agent for fillers and pigments. This important performance enhancement results from two mechanisms. First, the AEROSIL® particles envelop the pigment particles, preventing reagglomeration. Second, the pseudoplasticity of the coating as a result of using AEROSIL® products reduces the sedimentation of the pigments and fillers. The most effective AEROSIL® grade for this application depends on a number of factors, such as the binder used, the kind and concentration of pigments or fillers requiring stabilization, and the presence of other additives. 

AEROSIL® fumed silica is used very successfully as an anti-settling or suspension additive in applications such as zinc dust paints and anti-corrosion paints, the latter being based on black micaceous iron oxide, zinc phosphate or calcium silicate. AEROSIL 200 products have also proven themselves in electrically conductive coatings containing metallic powders or flakes. In particular it is relatively easy to prevent products with a low specific density from settling, for example, silica-based matting agents or various pigment blacks. 

Specification

specific surface area (BET): 175-225 m2/g

pH value (in 4% dispersion) 3.7-4.5

Loss on drying (2 hours at 105 C): <1,5%

Tamped density: appr. 50 g/L

SiO2 content (based on ignited material): >99,8%