Vermiculite board is a panel primarily made from expanded vermiculite, bonded with adhesives and other modifiers through compression molding. It possesses non-combustible, fire-resistant, and thermal insulation properties, also known as expanded vermiculite fireproof board. This relatively new insulation and fireproof material is primarily used in construction, furniture, firewalls, and ceilings. It can also be applied in fire escape routes, steel beam cladding, pipe insulation, fireplace linings, wall partitions, and in vehicles and ships.
Vermiculite boards exhibit non-combustibility, thermal insulation, sound absorption, moisture resistance, and freedom from harmful substances. When heated to 1200°C, they emit no hazardous gases detrimental to human health, producing no smoke, toxins, or odors. Their fire rating typically meets Class A standards. With a melting point of 1370–1400°C and a service temperature of 1200°C, it offers excellent flame retardancy and thermal insulation. Its thermal conductivity at 200°C is 0.13 W/(m·K), providing superior insulation performance suitable for a wide range of applications, including high-grade fireproof insulation scenarios. The primary functions of vermiculite boards are fireproofing and thermal insulation, with fire resistance directly impacting user safety as a critical metric. According to the Expanded Vermiculite Fireproof Board Standard (JC/T 2341-2015), boards with a thickness of 25mm must achieve a fire resistance rating of no less than 90 minutes. Combustion performance must meet Class A standards, with formaldehyde release not exceeding 9mg/100g.
The excellent fire resistance of vermiculite boards is closely related to their primary raw materials, material density, and structural design. The standard “Expanded Vermiculite Fireproof Board” (JC/T 2341-2015) also specifies requirements for the raw material expanded vermiculite. Expanded vermiculite must comply with JC/T 441, which imposes mandatory quality standards on parameters such as sieve residue and physical properties. Expanded vermiculite possesses an average bulk density of 100–130 kg/m³, featuring numerous void separation layers that provide excellent thermal insulation, sound absorption, and freeze resistance. Beyond its high-temperature insulation properties, expanded vermiculite can withstand temperatures up to 1200°C without melting. Therefore, vermiculite boards primarily manufactured from expanded vermiculite exhibit outstanding fire-resistant properties and are widely utilized. The density and structural design of vermiculite boards also influence their fire resistance. Lower density vermiculite boards offer reduced strength but superior thermal insulation. Conversely, higher density boards provide greater strength, requiring balanced consideration during production and application.
Although vermiculite boards offer good fire resistance, proper usage and adherence to safety precautions are essential to ensure safety during application. Additionally, vermiculite boards from different manufacturers may vary. It is advisable to review the product's technical specifications and certification standards before purchase to select compliant products.
