What are the building roof insulation materials? EPS and XPS, polyurethane, phenolic resin
EPS and XPS: EPS (polystyrene foam board, abbreviated as polystyrene board) is a kind of fine closed-cell structure obtained by heating and pre-expanding expandable polystyrene beads in a mold. Styrene foam sheet. It is currently the most commonly used insulation material. The skin layer has no pores, while the center layer contains a large number of fine closed pores, usually with a porosity of more than 90%. It has the advantages of light weight (weight density below 20kg/m3), good thermal insulation performance (thermal conductivity of 0.044W (mK)), good sound absorption performance, low price, easy processing, easy construction and operation, etc. A long history of use. At the same time, the EPS board has excellent moisture-proof performance and can be used for direct contact with moisture or water. In particular, it can be used for inverted insulation roofing, and has high application value on energy-saving roofing. XPS (extruded polystyrene foam board, abbreviated as extruded board) is made by using polystyrene resin as raw material and other raw materials and poly-storage materials, mixing and injecting catalyst by heating and then extruding and extruding. Rigid foam board. XPS has better thermal insulation performance than EPS. Under the same insulation requirements, its thickness can be smaller than other types of insulation materials, but XPS has almost no gas permeability. In areas with large indoor and outdoor temperature difference, water and gas are easy to cause. Condensation on both sides of the board. If the water gas stays for a long time and cannot be discharged, it will affect the bonding strength of the XPS board to some extent. According to the current requirements of building fire protection regulations, flame-retardant EPS and XPS are used, that is, by adding a flame retardant such as an organic halide to the raw material to change its combustion performance, thereby achieving the use requirement of the B1 grade.
Polyurethane foam: Polyurethane is a mixture of binary or polybasic organic isocyanates and polyols and other additives. It is divided into soft, semi-rigid and hard materials. It is used for thermal insulation materials. It is a rigid polyurethane (PUR) foam that can replace traditional perlite and vermiculite insulation materials and three felt four oil waterproof layers. Rigid polyurethane foam is easy to construct and is usually sprayed on the spot. It can be used on any complex structure roof. It can also be poured into a sheet and used as a roof insulation material. The molecular structure of the rigid polyurethane foam is a fully closed cell structure with a closed cell ratio of not less than 90%. When the density is 35~40kg/m3, the thermal conductivity is generally between 0018~0.024W/(m·K). Continuous dense skin and high-strength interconnected wall closed pores, ideal for impermeability, tensile strength requirements ≥100kpa, self-adhesive properties (no intermediate bonding material required), bonding to roofing and exterior walls Strong, wind-resistant and anti-negative wind pressure performance. The polyurethane rigid foam with good temperature difference resistance does not change significantly in the temperature of -20~80 °C, and it is resistant to erosion and aging, and the service life can reach more than 50 years. Single rigid polyurethane foam roofing investment is higher, so reducing costs is the future development direction of rigid polyurethane foam. And because it is an organic polymer material, the highest fire safety rating can only reach the B1 flame retardant level after the addition of flame retardant.
Phenolic resin foam: phenolic resin foam has the advantages of low thermal conductivity, good mechanical properties, excellent dimensional stability, low water absorption, good heat resistance, excellent electrical insulation and flame retardancy, especially suitable for some special roofing. As insulation material or other functional materials. Phenolic resin can work at a high temperature of 130 ° for a long time, and the instantaneous working temperature can reach 200~300°C. The insulation effect of phenolic foam is 2~3 times higher than that of ordinary roofing materials. As a kind of material that is difficult to burn, low smoke, low toxicity and heat insulation, phenolic foam can be used as roof insulation material for flammable warehouses. After the phenolic foam insulation board is installed on the roof, the insulation performance of the house is greatly enhanced, which can save more than 60% energy than the building without insulation layer.
Phenolic resin foam