EXPANDED
VERMICULITE
Expanded vermiculite synthetic aggregate is a lightweight, porous material produced by heating natural vermiculite, a hydrous phyllosilicate mineral, to high temperatures. During this process, the water trapped within the vermiculite structure turns to steam, causing the material to expand up to 30 times its original size. This expansion results in a lightweight aggregate with excellent insulation, fire resistance, and moisture retention properties, making it highly suitable for a variety of construction, industrial, and horticultural applications.
KEY COMPONENTS
1. Expanded Vermiculite:
- Composition: Vermiculite is a naturally occurring mineral, primarily composed of magnesium-aluminum-iron silicate. When heated to around 800–1000°C, the moisture in the vermiculite evaporates, causing it to expand and form lightweight, porous particles.
- Structure: The expansion process creates a flaky, accordion-like structure in the vermiculite particles, giving them a high degree of porosity. This structure contributes to the material’s low density, thermal insulation, and fire resistance.
2. Synthetic Binders or Matrix (Optional):
- Expanded vermiculite is often combined with synthetic binders, such as polymers, resins, or cement, to create composite aggregates for specific applications. These binders improve the aggregate's mechanical properties, such as compressive strength and durability, allowing for greater versatility in construction and industrial uses.
Properties and Benefits
​
1. Lightweight: Expanded vermiculite is a highly lightweight material, with a bulk density ranging from 60 to 150 kg/m³, depending on the particle size. Its low density makes it ideal for applications that require weight reduction, such as lightweight concrete, fireproofing materials, and insulation boards.
​
2. Thermal Insulation: Expanded vermiculite has excellent thermal insulation properties due to its porous structure, which traps air and reduces heat transfer. This makes it highly effective in applications such as insulating concrete, roof insulation, and thermal panels.
​
3. Fire Resistance: Vermiculite is non-combustible and has a high melting point, making it an excellent fire-resistant material. It is often used in fireproofing applications, such as sprayed fireproof coatings, fire-rated plaster, and fire-resistant boards, where it helps protect structures from fire damage.
​
4. Moisture Retention: Expanded vermiculite is highly porous and can absorb and retain large amounts of water. This property is beneficial in applications that require moisture management, such as horticulture, soil conditioning, and water retention systems. It also helps control humidity in building materials like plaster and mortar.
​
5. Chemical Resistance: Vermiculite is chemically inert and resistant to most acids, alkalis, and chemicals. This makes it suitable for use in environments exposed to corrosive substances, such as chemical processing plants and industrial insulation systems.
​
6. Acoustic Insulation: The porous nature of expanded vermiculite also provides excellent sound absorption properties, making it useful in acoustic panels, partition walls, and soundproofing materials in buildings where noise reduction is important.
​
7. Eco-Friendly and Sustainable: Vermiculite is a naturally occurring mineral and, when expanded, is a sustainable and environmentally friendly material. Its use in construction and industrial applications reduces the reliance on more resource-intensive materials and contributes to green building practices.
Applications
​
1. Lightweight Concrete: Expanded vermiculite is commonly used as a lightweight aggregate in lightweight concrete mixes. Its low density reduces the overall weight of the concrete, making it suitable for applications such as roof slabs, partition walls, and precast concrete elements, where weight reduction is a priority.
2. Fireproofing: Due to its excellent fire-resistant properties, expanded vermiculite is used in fireproofing materials, such as sprayed fireproof coatings, fire-resistant boards, and insulating plasters. These materials are applied to structural steel, walls, and ceilings in buildings to prevent or delay fire spread.
3. Thermal Insulation: Vermiculite's high thermal insulation properties make it ideal for use in insulating concrete, roofing systems, and thermal insulation boards. It is often used in high-temperature insulation for furnaces, chimneys, and kilns, as well as in energy-efficient building designs.
4. Horticulture and Soil Conditioning: Expanded vermiculite is widely used in horticulture as a soil amendment and growing medium. Its ability to retain moisture and improve aeration makes it suitable for seed starting, plant propagation, and soil conditioning. It helps retain moisture and nutrients while improving drainage in potting mixes and garden soils.
5. Acoustic Insulation: Vermiculite's sound-absorbing properties make it useful in acoustic panels, soundproof walls, and ceiling tiles. It helps reduce noise transmission in buildings, making it suitable for use in offices, residential spaces, and industrial environments where noise control is essential.
6. Industrial Applications: Expanded vermiculite is used in a variety of industrial applications, such as high-temperature insulation, refractory linings, and foundry applications. Its fire-resistant and chemical-resistant properties make it suitable for use in high-temperature environments, furnaces, and kilns, as well as in industrial plants that handle corrosive chemicals.
7. Loose-Fill Insulation: Expanded vermiculite is often used as loose-fill insulation in attics, walls, and cavities. Its lightweight and insulating properties help improve the thermal efficiency of buildings, while its fire-resistant nature enhances overall safety.
8. Plaster and Mortar: Expanded vermiculite is added to plaster and mortar mixtures to improve workability, reduce weight, and enhance insulation properties. It is commonly used in lightweight plaster for walls and ceilings, as well as in fire-resistant mortars for industrial applications.
Expanded vermiculite synthetic aggregate is a versatile, lightweight, and highly insulating material with a wide range of applications in construction, horticulture, and industry. Its properties, including fire resistance, thermal insulation, moisture retention, and sound absorption, make it an ideal choice for lightweight concrete, fireproofing, and insulating materials. Additionally, its eco-friendly nature and chemical inertness contribute to sustainable building practices and durable, high-performance structures.