Description

Fumed Silica CAS NO 112945-52-5 is a high-purity, amorphous silicon dioxide produced via flame hydrolysis of silicon tetrachloride, resulting in an ultra-fine powder with an extremely high surface area. This material is a critical performance additive, valued for its exceptional rheological control, thickening, and reinforcing properties. It is essential for manufacturers in the adhesives & sealants, coatings, composites, pharmaceuticals, and food industries seeking to modify viscosity, prevent settling, and enhance mechanical strength.

Application

• Rheology Modifier & Thickener: Provides thixotropic behavior and sag resistance in adhesives, sealants, silicone rubber, and gel coats.
• Anti-caking & Free-flow Agent: Prevents caking and ensures free flow in powdered food products, spices, and industrial powders.
• Reinforcing Filler: Enhances tensile strength, tear resistance, and modulus in silicone elastomers and polymer composites.
• Viscosity Control in Coatings: Imparts anti-settling properties and controls flow in paints, inks, and industrial coatings.
• Pharmaceutical & Cosmetic Applications: Acts as a viscosity-increasing agent, stabilizer, and carrier in creams, ointments, and tablets.
• Thermal Insulation: Used as a key component in high-temperature insulation blankets and boards.
• Defoamer Carrier: Serves as an inert carrier for liquid defoamers in various process industries.

Basic Information

Product Name	Fumed Silica
CAS No.	112945-52-5
Molecular Formula	SiO₂
Molecular Weight	60.08 g/mol
Synonyms	Pyrogenic Silica; Colloidal Silicon Dioxide; Amorphous Silica; Silica, Fumed; Aerosil® (common trade name); Cab-O-Sil® (common trade name); Hydrophilic Fumed Silica; Synthetic Amorphous Silica (SAS)
EINECS	Contact for details

Quality Control

Our Fumed Silica is manufactured under strict quality management systems. Each batch undergoes rigorous testing for critical parameters including surface area, particle size, pH, and loss on drying to ensure batch-to-batch consistency and performance. Certificates of Analysis (COA) are provided and the product can be supplied to meet relevant industry standards such as USP/NF for colloidal silicon dioxide, food grade (FCC), and REACH compliance.

Storage

Preserve in a tightly closed container, protected from light. This material is hygroscopic (moisture-sensitive). Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). Keep the container tightly sealed when not in use to minimize moisture absorption, which can affect product performance.

Specification

Item	Specification
Appearance	White, fluffy powder
Assay (SiO₂)	≥ 99.8%
Surface Area (BET)	50 - 400 m²/g (grade dependent)
Loss on Drying (105°C)	≤ 1.5%
pH (in 4% suspension)	3.7 - 4.5
Tamped Density	30 - 100 g/L (grade dependent)
Sieve Residue (45μm)	≤ 0.05%
Heavy Metals (as Pb)	≤ 10 ppm

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.