零能耗房屋,酚醛保温板:
Low Energy House - What is Phenolic Insulation?
A low thermal conductivity allows specified thermal performance targets to be achieved with minimal thickness of insulation. This is particularly significant where space saving is important
Phenolic Insulation Manufacturing Process
Phenolic insulation board is manufactured by a process in which a plastic foam forms an insulating core between two flexible facing layers. It has a high closed cell content and fine cell structure.
Rigid phenolic insulation is produced by mixing high solids and phenolic resin with a surface acting agent. The heat created by the reaction evaporates a volatile liquid blowing agent in the mixture which produces a network of small bubbles in the material. The foam can be cured to create one of two forms of the product. It can be manufactured by a continuous process to create thin sheet material which is laminated with various facings and cut into boards. Alternatively, it can be made into blocks to be cut into pre-determined shapes.
Phenolic Insulation - Blowing Agent
In order to comply with EC regulations, blowing gases should be CFC and HCFC free (zero ozone depletion potential) and have low global warming impact. The most common blowing agent used in this type of insulation production is pentane. Pentane is a hydrocarbon which has similar properties to those of butane and hexane. It is the most volatile hydrocarbon that is a liquid at room temperature. There is a slight risk that over time the blowing agent may escape and be replaced by air. In order to help eliminate this risk, as part of the manufacturing process, the rigid boards are faced with, gas tight, aluminium foil or glass tissue.
Main Uses of Phenolic Insulation
Rigid phenolic insulation can be used for partial fill cavity wall insulation, pitched roof insulation and insulated dry lining.
Phenolic Insulation - Thermal Performance
Rigid phenolic insulation products offer very good thermal insulating properties due to the very low thermal conductivity of phenolic foam, compared with rigid polyurethane or extruded polystyrene. Its low thermal conductivity allows specified thermal performance targets to be achieved with minimal thickness of insulation. This is particularly significant where space saving is important.
Foil Facings on Rigid Phenolic Insulation
If installed correctly, the reflective foil can also act as a radiant barrier that adds greater resistance to the insulating assembly. The low emissivity facings improve the thermal performance when positioned next to an un-ventilateded airspace. This makes the material particularly effective when it is used to partially fill cavities in external walls.
Physical Qualities of Phenolic Insulation
Thermal Performance of Phenolic Insulation
The thermal conductivity of phenolic foam in the density range 35-60 kg.m³ is typically 0.020 W/m K.
In the UK, when comparing the thermal values of insulation materials, it is important to remember that the best performing material is the one with the lowest thermal conductivity value