Polyurethane insulation because of the following properties, in the field of building energy-saving materials occupy an important position:
Low density, low thermal conductivity and a wide range of application temperature
Typically, rigid polyurethane foam density of 30-50kg / m3. This and other foam insulation materials, such as EPS board, XPS board and phenolic resin foam board. However, in achieving the same insulation properties, rigid polyurethane foam It is obviously lighter than other foam materials, which means that it is easier to transport and install, and the rigid polyurethane foam has a very excellent thermal insulation performance compared with other insulation materials, that is to say, in order to achieve the same Insulation properties, rigid polyurethane foam thinner than other materials: Can be compared, 3cm thick polyurethane insulation board roughly the same thermal performance as 4cm thick XPS board and 5cm thick EPS board can be said that the application of rigid polyurethane foam saving A considerable amount of space is a good deal for those areas where the thermal insulation board is included in the floor area ratio, and there is a wide range of temperature applications for rigid polyurethane foams: from -200 ° C to 100 ° C.
(2) high strength
Rigid polyurethane foam with high compressive strength, adhesion and shear strength, that is, it can withstand rolling and wind, and other materials, such as glass wool material can not do this. Rockwool insulation material settlement and Thinning causes a 10% to 20% reduction in U. Therefore, materials such as glass wool can not be applied directly to thin plaster walls, but rock wool, EPS panels, etc. can not be applied directly to underpressure Roof and floor insulation. The inherent strength of polyurethane materials can also be further strengthened by the use of metal cladding to form a composite structure.
(3) low moisture absorption, air tightness
Hard foam polyurethane foam also has low moisture absorption, which means that it has longer life than other insulation materials (such as glass wool), which can play more effective in its excellent thermal insulation properties.Research shows that glass wool insulation material At 1% water, its U value (a measure of the insulation effect) is reduced by 86%. Foam Polyurethanes also have airtightness due to their high closed cell ratio, which is characteristic of other insulation materials such as glass wool Do not have
(4) good fire performance
By adjusting the formula, rigid foam polyurethane material can meet the requirements of domestic and international standards.It does not like the EPS or XPS material has the phenomenon of melting and dripping, and rigid foam polyurethane material in the combustion process, will form a Coking protective layer to suppress the spread of burning.In addition, the metal veneer can further enhance the flame retardant properties of polystyrene foam can not be compared in the performance of fire, it will soften at 74 ℃, melting around 96 ℃ Using polystyrene foam as a thermal insulation, the thermal insulation of a foam decays over time due to its softening point and melting point being very close to the temperature of the wall and roof.
Many foreign countries have adopted the metal surface of the polyurethane composite board.I believe many people will ask a question: polyurethane insulation board surface covered with a smooth metal foil, but also how to apply plastering mortar? In fact, we see these cases, these are Not thin plaster insulation system, but the dry curtain wall system and sandwich insulation system.Many domestic are mortar coated polyurethane, why foreigners will use metal surface? This layer of metal surface is the role of heat reflection, the truth Very simple, polyurethane board itself can play a good role in insulation, but we hope insulation board can play in the summer heat insulation, then this layer of metal film can play a role.