Projected polyurethane is a plastic material with a cellular composition used as a thermal and acoustic insulator and as a waterproofing agent in both buildings and industry.[1] It is also known by the name polyurethane foam.
History
The discovery of polyurethane dates back to 1937, thanks to the research carried out by Otto Bayer. It began to be used in the 1950s, since until then there were no machines capable of processing it.
Description
The mixture of the two components polyol and isocyanate, liquid at room temperature, produces an exothermic chemical reaction. This chemical reaction is characterized by the formation of bonds between the polyol and the isocyanate, achieving a solid, uniform and very resistant structure. If the heat given off by the reaction is used to evaporate a swelling agent, a rigid product is obtained that has a cellular structure, with a volume much larger than that occupied by the liquid products. This is what we call rigid polyurethane foam, or PUR.
Rigid polyurethane foam is a duroplastic synthetic material, highly spatially cross-linked and non-fusible. At the usual densities, for thermal insulation, the foam contains only a small part of solid matter (with a density of 35 kg/m³, only 3% of the volume is solid matter).
Rigid polyurethane foam applied in situ by spraying, or sprayed polyurethane, is obtained by simultaneous spraying of the two components on a surface called substrate.
Properties
Thermal insulation.
• - Sprayed polyurethane has a low conductivity value, around 0.028 W/m•K, but it depends on the density and proper installation.
• - The insulation capacity of the sprayed polyurethane is very robust against the aging effects to which thermal insulation is usually exposed.
• - With sprayed polyurethane it is easier to control thermal bridges since the thickness of the insulation can be maintained and the geometries considered appropriate for the solution can be created.
• - Sprayed polyurethane achieves a high level of insulation with little thickness, but there are regulatory minimums.
Waterproofing pathology
Introduction
Projected polyurethane is a plastic material with a cellular composition used as a thermal and acoustic insulator and as a waterproofing agent in both buildings and industry.[1] It is also known by the name polyurethane foam.
History
The discovery of polyurethane dates back to 1937, thanks to the research carried out by Otto Bayer. It began to be used in the 1950s, since until then there were no machines capable of processing it.
Description
The mixture of the two components polyol and isocyanate, liquid at room temperature, produces an exothermic chemical reaction. This chemical reaction is characterized by the formation of bonds between the polyol and the isocyanate, achieving a solid, uniform and very resistant structure. If the heat given off by the reaction is used to evaporate a swelling agent, a rigid product is obtained that has a cellular structure, with a volume much larger than that occupied by the liquid products. This is what we call rigid polyurethane foam, or PUR.
Rigid polyurethane foam is a duroplastic synthetic material, highly spatially cross-linked and non-fusible. At the usual densities, for thermal insulation, the foam contains only a small part of solid matter (with a density of 35 kg/m³, only 3% of the volume is solid matter).
Rigid polyurethane foam applied in situ by spraying, or sprayed polyurethane, is obtained by simultaneous spraying of the two components on a surface called substrate.
Properties
Thermal insulation.
• - Sprayed polyurethane has a low conductivity value, around 0.028 W/m•K, but it depends on the density and proper installation.
• - The insulation capacity of the sprayed polyurethane is very robust against the aging effects to which thermal insulation is usually exposed.
Acoustic conditioner.
• - The use of open cell foams also has a positive acoustic absorption effect. It can suffer wear and aging, increasing its deterioration if it is left visible.
Waterproofing of facades.
• - The sprayed polyurethane, being an intermediate continuous system, without prior plastering, meets the maximum degree of impermeability of the facades in the simplest and most economical way.
Humidity control.
• - The sprayed polyurethane, being impermeable to water, allows the enclosure to breathe.
• - In those construction solutions in which there is a risk of condensation, it will be necessary to interpose a vapor barrier in situ to avoid pathologies.
Fire safety.
• - The fire reaction classification of bare sprayed polyurethane ranges from C,s3-d0 to E.
• - The classification in final use application ranges from B-s1,d0 to F.
• - The CTE allows the use of polyurethane in most applications.
• - In ventilated facades of more than 18 m it is necessary to protect the foam.
Healthiness.
• - Polyurethane is a completely harmless and healthy material for humans, if it is properly protected and applied on site with sufficient ventilation guarantees. It contains HCN (hydrogen cyanide) which is harmful to health in case of fire.
Sustainability.
• - Sprayed polyurethane helps reduce thermal losses, economically, and guaranteeing people's comfort. Its production is not ecological.
Mechanical resistance.
• - The compression resistance varies linearly with the density, thus we have a compression resistance greater than 200 kPa, valid for roofs and floors, in foams of more than 40 kg/m³.
Chemical stability.
• - The sprayed polyurethane can be painted, varnished, glued, coated, or can be used as a coating for premises with aggressive atmospheres, as long as it is guaranteed that it will not have contact with fire.
Adherence.
• - It has great adhesion on consistent, clean and dry substrates.
• - Its adhesion compared to other materials can be improved by scratching the surface to be covered or by using a primer.
• - Does not adhere well to plastics such as polyethylene.
• - Does not adhere to materials such as PTFE or Teflon, or polypropylene.
Putting into work.
• - Being a material sprayed in situ, sprayed polyurethane has great versatility and countless advantages during construction.
Standardization.
• - Sprayed polyurethane is a construction product with AENOR UNE Standard for both the manufacturing of systems and the application, since 1998.
Certification.
• - The sprayed polyurethane can certify its properties before installation and once installed on site.
Applications
Façade with interior insulation and wet partitions.
Facade with interior insulation and dry partitions.
Façade with exterior insulation and continuous coating.
Ventilated facade.
Façade with injection chamber.
Passable flat roof.
Flat roof not passable.
Inclined roof.
Insulated cover between pigeon walls.
Lightweight cover insulated on the inside.
Lightweight cover insulated on the outside.
Ceiling.
Floor.
• - White Paper on Projected Polyurethane.
• - ATEPA, Technical Association of Applied Polyurethane.
• - IPUR, Rigid Polyurethane Industry Association.
• - With sprayed polyurethane it is easier to control thermal bridges since the thickness of the insulation can be maintained and the geometries considered appropriate for the solution can be created.
• - Sprayed polyurethane achieves a high level of insulation with little thickness, but there are regulatory minimums.
Acoustic conditioner.
• - The use of open cell foams also has a positive acoustic absorption effect. It can suffer wear and aging, increasing its deterioration if it is left visible.
Waterproofing of facades.
• - The sprayed polyurethane, being an intermediate continuous system, without prior plastering, meets the maximum degree of impermeability of the facades in the simplest and most economical way.
Humidity control.
• - The sprayed polyurethane, being impermeable to water, allows the enclosure to breathe.
• - In those construction solutions in which there is a risk of condensation, it will be necessary to interpose a vapor barrier in situ to avoid pathologies.
Fire safety.
• - The fire reaction classification of bare sprayed polyurethane ranges from C,s3-d0 to E.
• - The classification in final use application ranges from B-s1,d0 to F.
• - The CTE allows the use of polyurethane in most applications.
• - In ventilated facades of more than 18 m it is necessary to protect the foam.
Healthiness.
• - Polyurethane is a completely harmless and healthy material for humans, if it is properly protected and applied on site with sufficient ventilation guarantees. It contains HCN (hydrogen cyanide) which is harmful to health in case of fire.
Sustainability.
• - Sprayed polyurethane helps reduce thermal losses, economically, and guaranteeing people's comfort. Its production is not ecological.
Mechanical resistance.
• - The compression resistance varies linearly with the density, thus we have a compression resistance greater than 200 kPa, valid for roofs and floors, in foams of more than 40 kg/m³.
Chemical stability.
• - The sprayed polyurethane can be painted, varnished, glued, coated, or can be used as a coating for premises with aggressive atmospheres, as long as it is guaranteed that it will not have contact with fire.
Adherence.
• - It has great adhesion on consistent, clean and dry substrates.
• - Its adhesion compared to other materials can be improved by scratching the surface to be covered or by using a primer.
• - Does not adhere well to plastics such as polyethylene.
• - Does not adhere to materials such as PTFE or Teflon, or polypropylene.
Putting into work.
• - Being a material sprayed in situ, sprayed polyurethane has great versatility and countless advantages during construction.
Standardization.
• - Sprayed polyurethane is a construction product with AENOR UNE Standard for both the manufacturing of systems and the application, since 1998.
Certification.
• - The sprayed polyurethane can certify its properties before installation and once installed on site.
Applications
Façade with interior insulation and wet partitions.
Facade with interior insulation and dry partitions.
Façade with exterior insulation and continuous coating.
Ventilated facade.
Façade with injection chamber.
Passable flat roof.
Flat roof not passable.
Inclined roof.
Insulated cover between pigeon walls.
Lightweight cover insulated on the inside.
Lightweight cover insulated on the outside.
Ceiling.
Floor.
• - White Paper on Projected Polyurethane.
• - ATEPA, Technical Association of Applied Polyurethane.
• - IPUR, Rigid Polyurethane Industry Association.