Polyurethane foam made with an aromatic isocyanate, which has been exposed to UV light. Readily apparent is the discoloration that occurs over time.Custom-cast polyurethane objects
Polyurethane products have many uses. Over three quarters of the global consumption of polyurethane products is in the form of foams, with flexible and rigid types being roughly equal in market size. In both cases, the foam is usually behind other materials: flexible foams are behind upholstery fabrics in commercial and domestic furniture; rigid foams are between metal, or plastic walls/sheets of most refrigerators and freezers, or other surface materials in the case of thermal insulation panels in the construction sector. Its use in garments is growing: for example, in lining the cups of brassieres. Polyurethane is also used for moldings which include door frames, columns, balusters, window headers, pediments, medallions and rosettes.
Hard solid plastics used as electronic instrument bezels and structural parts
Flexible plastics used as straps and bands
Cast and injection molded components for various markets – i.e., agriculture, military, automotive, industrial, etc.
Polyurethane foam is widely used in high resiliency flexible foam seating, rigid foam insulation panels, microcellular foam seals and gaskets, durable elastomeric wheels and tires, automotive suspension bushings, electrical potting compounds, seals, gaskets, carpet underlay, and hard plastic parts (such as for electronic instruments).
Applications of polyurethane materials, plotted by density and stiffness.This repaired shoe is probably, like many shoes, soled with polyurethane. PU soles may crumble due to hydrolysis.
Usage per application
The following table shows an example how polyurethanes were used in one country over a dozen years ago (US data from 2004):
Application
Usage (millions of pounds)
Proportion of total
Building & construction
1,459
26.8%
Transportation
1,298
23.9%
Furniture & bedding
1,127
20.6%
Appliances
278
5.1%
Packaging
251
4.6%
Textiles, fibers & apparel
181
3.3%
Machinery & foundry
178
3.3%
Electronics
75
1.4%
Footwear
39
0.7%
Other uses
558
10.2%
Total
5,444
100.0%
Cleaning products
Polyurethane foam sponge
Open-cell flexible polyurethane foam is used to make many kitchen and bathroom sponges. The combination of low cost, high flexibility and high abrasion and tear resistance make polyurethanes excellent materials for scrubbing applications. [3] Polyurethane sponges have been shown to reduce the risk of spreading certain bacteria. [4]
Industrial Insulation
Industrial Insulation
Rigid polyurethane foam is used in various industries to provide thermal insulation to installations and pipes. In particular, the piping for district heating systems in Europe is primarily insulated using a pre-insulated pipes sandwich assembly composed of a steel heat service pipe, an insulating layer (polyurethane foam) and a polyethylene (PE) casing, which are bonded by the insulating material. One of the main advantages of rigid polyurethane foam is that it offers a very low thermal conductivity (with values as low as 23mW/m⋅K) while offering enough structural strength to withstand the loads that buried pipe systems are subjected to. [5][6]
Due to the closed-cell nature of rigid polyurethane foams, PUR insulation has minimal water absorption, which coupled with an appropriate cover, makes it a particularly suitable in applications where bacterial growth is a concern. Polyurethane insulation is suitable for insulating pipes with surface temperatures ranging from -196°C to 148°C. [7]
Open cell flexible polyurethane foam (FPF) is made by mixing polyols, diisocyanates, catalysts, auxiliary blowing agents and other additives and allowing the resulting foam to rise freely. Most FPF is manufactured using continuous processing technology and also can be produced in batches where relatively small blocks of foam are made in open-topped molds, boxes, or other suitable enclosurers. The foam is then cut to the desired shape and size for use in a variety of furniture and furnishings applications.
Applications for flexible polyurethane foam include upholsteredfurniture cushions, automotive seat cushions and interior trim, carpet cushion, and mattress padding and solid-core mattress cores.
Flexible polyurethane foam is a recyclable product. [8]
Automobile seats
Flexible and semi-flexible polyurethane foams are used extensively for interior components of automobiles, in seats, headrests, armrests, roof liners, dashboards and instrument panels.
Polyurethane foam in the lower half of the mold in which it was made. When assembled into a car seat, this foam makes up the seat back. The forward-facing part of the seat back is the surface of the foam which is face-down in the mold. The two holes in the foam at the top of the picture are for the headrest posts.
Foam seat back after removal from the mould
Polyurethanes are used to make automobile seats in a remarkable manner. The seat manufacturer has a mold for each seat model. The mold is a closeable "clamshell" sort of structure that will allow quick casting of the seat cushion, so-called molded flexible foam, which is then upholstered after removal from the mold.
It is possible to combine these two steps, so-called in-situ, foam-in-fabric or direct moulding. A complete, fully assembled seat cover is placed in the mold and held in place by vacuum drawn through small holes in the mold. Sometimes a thin pliable plastic film backing on the fabric is used to help the vacuum work more effectively. The metal seat frame is placed into the mold and the mold closed. At this point the mold contains what could be visualized as a "hollow seat", a seat fabric held in the correct position by the vacuum and containing a space with the metal frame in place.
Polyurethane chemicals are injected by a mixing head into the mold cavity. Then the mold is held at a preset reaction temperature until the chemical mixture has foamed, filled the mold, and formed a stable soft foam. The time required is two to three minutes, depending on the size of the seat and the precise formulation and operating conditions. Then the mold is usually opened slightly for a minute or two for an additional cure time, before the fully upholstered seat is removed.
Houses, sculptures, and decorations
The walls and ceiling (not just the insulation) of the futuristic Xanadu House in Florida, USA, were built out of polyurethane foam. Domed ceilings and other odd shapes are easier to make with foam than with wood. Foam was used to build oddly shaped buildings, statues, and decorations in the Seuss Landing section of the Islands of Adventure (USA) theme park. Rigid foam manufacturers sell foam that replace wood in carved sign and 3D-topography industries. PU foam is also used as a thermal insulator in many houses.
Polyurethane resin is used as an aesthetic flooring material. Being seamless and water resistant, it is gaining interest for use in (modern) interiors, especially in Western Europe.
Polyurethane being used as an insulator in house construction (yellow layer).
Polyurethane foam as a wall insulation
Xanadu House with polyurethane foam walls and ceiling
Polyurethane foam used as joist cavity insulation at a restaurant near Philadelphia, not in direct sunlight, exhibiting shrinkage at the bond interface.
Two binary liquids, one of which is a polyurethane (either T6 or 16), when mixed and aerated, expand into a hard, space-filling aerosolid.
Construction sealants and firestopping
Polyurethane foam, misapplied as firestop.
Approved polyurethane sealants (which is different from foam) are available in one, two and three part systems, and in cartridges, buckets or drums. Polyurethane sealants (such as EZ-Poly) are used to fill gaps thereby preventing air and water leakage. They are also used in conjunction with inorganic insulation, such as rockwool or ceramic fibres, for firestopping. Firestops can thwart smoke and hose-stream passage. The Browns Ferry Nuclear Power Plant used flammable polyurethane foam as a firestop, which was accidentally ignited and caused a major fire.
Water vessels
Polyurethane foam is widely used in the marine world in many applications:[9]
Inflatable boats
Some raft manufacturers use urethane for the construction of inflatable boats. AIRE uses urethane membrane material as an air-retentive bladder inside a PVC shell, whereas SOTAR uses urethane membrane materials as a coating on some boats. Maravia uses a liquid urethane material which is spray-coated over PVC to enhance air retention and increase abrasion resistance.
Surfboards
Some surfboards are made with a rigid polyurethane core. A rigid foam blank is molded, shaped to specification, then covered with fiberglass cloth and polyester resin.
Rigid-hulled boats
Some boat hulls have a rigid polyurethane foam core sandwiched between fiberglass skins. The foam provides strength, buoyancy, and sound deadening. Foam Supplies Inc. produces a wide range of eco-friendly polyurethane products used in flotation materials including: Ecomarine®, Spritzer™ Marine, and Kit Foam as well as boat seating and accessories.[10]
Boat decks and outdoor marine surface areas
Some boat decks including U.S Navy and Pakistani fishing vessels use specialized polyurethane sealants to protect from constant moisture and harsh oceanic elements. As an example, Durabak-M26 uses a custom single-part polyurethane to prevent water seepage to unwanted areas.
Water tanks
Some water tanks are insulated with polyurethane chemicals (polyol and isocyanates) to maintain water temperature for long periods of time.
Flexible plastics
Tennis grips
Polyurethane has been used to make several Tennis Overgrips such as Yonex Super Grap, Wilson Pro Overgrip and many other grips. These grips are highly stretchable to ensure the grip wraps neatly around the racquet's handle.
Watch-band wrapping
Polyurethane watch strap
Polyurethane is used as a black wrapping for timepiece bracelets over the main material which is generally stainless steel. It is used for comfort, style, and durability.
Textiles
Polyurethane fiber (spandex) clothing
A thin film of polyurethane finish is added to a polyester weave to create polyurethane laminate (PUL), which is used for its waterproof and windproof properties in outerwear, diapers, shower curtains, and so forth. PU is used in some cutting-edge swimsuits to provide buoyancy for competitive swimmers. There are restrictions as the buoyancy enhances swimming performance.[citation needed]
A still more popular use of polyurethane in textiles is in the form of spandex, also known as elastane or by DuPont's brand name Lycra. Polyurethane fibers in the form of spandex can stretch up to 600% and still return to their original shape. Spandex is spun with other fibers, such as cotton, nylon, or polyester, to create stretchable fibers essential for clothing for both sports and fashion.[11]
Polyurethane materials are commonly formulated as paints and varnishes for finishing coats to protect or seal wood. This use results in a hard, abrasion-resistant, and durable coating that is popular for hardwood floors, but considered by some to be difficult or unsuitable for finishing furniture or other detailed pieces. Relative to oil or shellac varnishes, polyurethane varnish forms a harder film which tends to de-laminate if subjected to heat or shock, fracturing the film and leaving white patches. This tendency increases when it is applied over softer woods like pine. This is also in part due to polyurethane's lesser penetration into the wood. Various priming techniques are employed to overcome this problem, including the use of certain oil varnishes, specified "dewaxed" shellac, clear penetrating epoxy, or "oil-modified" polyurethane designed for the purpose. Polyurethane varnish may also lack the "hand-rubbed" lustre of drying oils such as linseed or tung oil; in contrast, however, it is capable of a much faster and higher "build" of film, accomplishing in two coats what may require many applications of oil. Polyurethane may also be applied over a straight oil finish, but because of the relatively slow curing time of oils, the presence of volatile byproducts of curing, and the need for extended exposure of the oil to oxygen, care must be taken that the oils are sufficiently cured to accept the polyurethane.
Unlike drying oils and alkyds which cure, after evaporation of the solvent, upon reaction with oxygen from the air, polyurethane coatings cure after evaporation of the solvent by a variety of reactions of chemicals within the original mix, or by reaction with moisture from the air. Certain products are "hybrids" and combine different aspects of their parent components. "Oil-modified" polyurethanes, whether water-borne or solvent-borne, are currently the most widely used wood floor finishes.
Exterior use of polyurethane varnish may be problematic due to its susceptibility to deterioration through ultra-violet (UV) light exposure. All clear or translucent varnishes, and indeed all film-polymer coatings (i.e., paint, stain, epoxy, synthetic plastic, etc.) are susceptible to this damage in varying degrees. Pigments in paints and stains protect against UV damage, while UV-absorbers are added to polyurethane and other varnishes (in particular "spar" varnish) to work against UV damage. Polyurethanes are typically the most resistant to water exposure, high humidity, temperature extremes, and fungus or mildew, which also adversely affect varnish and paint performance.
Wheels
Polyurethane wheels in inline skates
Polyurethane is also used in making solid tires and wheels. Industrial applications include forklift drive and load wheels, grocery and industrial carts,[12] and roller coaster wheels. Modern roller blading and skateboarding became economical only with the introduction of tough, abrasion-resistant polyurethane parts, helping to usher in the popularity of what had once been an obscure 1960s craze. The durability of polyurethane wheels allowed the range of tricks and stunts performed on skateboards to expand considerably. Polyurethane is also used to make small equipment tires in the lawn and garden industry for wheelbarrows, hand trucks, lawn mowers, carts, etc. They provide the bounce and feel of an air-filled tire with the benefit of no punctures. They weigh about the same as air-filled tires as well, even though they are solid polyurethane all the way through. Other constructions have been developed for pneumatic tires, and microcellular foam variants are widely used in tires on wheelchairs, bicycles and other uses. These latter foam types are also widely encountered in car steering wheels and other interior and exterior automotive parts, including bumpers and fenders.
Automotive parts
Polyurethane usage has increased over the past twenty years in the automotive industry. It is being used to replace traditional rubber bushings which are known to fail or wear out on road surfaces prone to large amounts of salt and chemical debris.
Using polyurethane bushings can have many benefits like maintaining the right alignment of caster, camber and toe and thereby increasing the overall control and handling. It also increases the lifespan, provides more resistance to wear out and is less pervious to oil and similar road contaminants.[13]
Polyurethane (PU) is popularized in the manufacturing of some of the highest quality aerodynamic components /body kits (body kits) for varying automobiles (car, truck, and SUV) on the market. These components include bumpers, side skirts, roll pans, and wiper cowls. Polyurethane allows production of durable components unlike the conventional fiberglass (FRP) that can easily break upon impact. Polyurethane is highly flexible therefore more resistant to damage. Including durability, these body kits when produced by a reputable manufacturer, exhibits less imperfections, are easy to install and maintain, and are affordable.[14]
When fiberglass body kits begin to show cracks, chips from usual wear and tear, a well manufactured polyurethane components have similar durability to a factory installed bumper. As mentioned above, when produced by a reputable manufacturer, tend to have less pinholes and casting imperfections. Flexibility of polyurethane makes them easy to work with. Installation can be completed individually as a "do-it-yourself" project. Maintenance is extremely simple. Concerning pricing, it may vary depending on the manufacturer but are kept between an affordable range. As good as it sounds, polyurethane body kits too have its downfalls. Fiberglass or carbon fiber components are lighter in weight than most polyurethane kits. Polyurethane, again is flexible but more material and thickness is most often needed to keep adequate stiffness for road use. For drivers seeking speed for their higher performance vehicle,[15] this can become a problem. Also, unlike fiberglass, polyurethane cannot be patched or repaired. Though it is much harder to damage, if damage did occur, the entire component must be removed and replaced.[14] There are varying options when purchasing polyurethane kits.
Electronic components
Often electronic circuit components and wires are protected from environmental influence and mechanical shock by enclosing them in polyurethane. Typically polyurethanes are selected for the excellent abrasion resistances, good electrical properties, excellent adhesion, impact strength, and low-temperature flexibility. The disadvantage of polyurethanes is the limited upper service temperature (typically 250°F (121°C)).
The production the electronic circuit-board manufacture would use a two-part urethane (resin and catalyst) that would be mixed and poured onto the circuit assembly (see resin dispensing). In most cases, after the urethane cures, the completed circuit board would not be repairable. Because of its physical properties and low cost, polyurethane encapsulation (potting) is a popular option in the automotive manufacturing sector for automotive circuits and sensors.
Adhesives
Polyurethane can be used as an adhesive, especially as a woodworking glue. Its main advantage over more traditional wood glues is its water resistance. It was introduced to the general North American market in the 1990s as Gorilla Glue and Excel, but had been available in Europe much earlier. Polyurethane is the basis for some construction adhesives in a caulking tube format.[16]
On the way to a new and better glue for bookbinders, a new adhesive system was introduced for the first time in 1985. The base for this system is polyether or polyester, whereas polyurethane (PUR) is used as prepolymer. Its special features are coagulation at room temperature and resistance to moisture.[citation needed]
First generation (1988)
Low starting solidity
High viscosity
Cure time >3 days
Second generation (1996)
Low starting solidity
High viscosity
Cure time <3 days
Third generation (2000)
Good starting solidity
Low viscosity
Cure time between 6 and 16 hours
Fourth generation (present)
Good starting solidity
Very low viscosity
Cure reached within a few seconds due to dual-core systems
Advantages of polyurethane glue in the bookbinding industry:
PUR is better than hotmelt or cold glue for most applications. Because of the lack of moisture in the glue, paper with contrary grain direction can be glued without problems. Even printed and supercalendered paper can be bound without problems. It is the most economical glue, with a theoretical application thickness of 0.01mm. However, in actual use, it is not practical to apply less than 0.03mm.
PUR glue is weather-proof, and stable at temperatures from −40°C (−40°F) to 100°C (212°F).[17]
Abrasion resistance
Thermoset polyurethanes are also used as a protective coating against abrasion. Cast polyurethane over materials such as steel will absorb particle impact more efficiently. Polyurethanes have been proven to last in excess of 25 years in abrasive environments where non-coated steel would erode in less than 8 years. Polyurethanes are used in industries such as:
Mining and mineral processing
Aggregate
Transportation
Concrete
Paper processing
Power
Inflatable boat manufacture
Polyurethane is also used in the concrete construction industry to create formliners. Polyurethane formliners serves as a mold for concrete, creating a variety of textures and art.
Sheet and flaked semi-open cell hydrophilic polyurethane foams have found application in roof gardens and vertical green walls with commercial products now emerging on the market.[20] Semi-open cell polyurethane foams substrates have much lower density and far greater water holding capacities than soil substrates. The semi-open cell structure facilitate the required plant root attachment for vertical wall gardens. Reductions in weight reduce building/wall supporting structure requirements, whilst increased water holding capacity reduces plant watering requirements.
Concrete raising
PU-containing sea defenses being installed on Hallig Gröde, an island off the German coast
Closed cell polymers have been used to raise and support concrete roadways and bridge approaches since 1989. Originally developed in Europe and patented by Uretek, this method of concrete leveling is now widely used in residential, commercial and municipal applications. Common applications include repairing settled sidewalks, driveways, patios and garage floors.[21] In the US it is sometimes known as Slabjacking. Foam Supplies Incorporated have developed the eco-friendly FoamJack™ system.
Concrete substitute
Polyurethane foam as backfill
Closed cell polyurethane foam can be used as backfill in applications where the high density and compression strength of concrete are not necessary.[22] In addition to being considerably lighter than concrete, the closed cell nature of the material prevents the transfer of moisture to the structure being supported which can reduce the risk or rot or corrosion.[23]
Seawall Repair
Environmental variables, natural wear and tear, and weather conditions, can all cause damage to concrete seawalls. These problems can erode the structure over time, rendering it more susceptible to further harm. Traditionally repair has required an in depth process using concrete, however geofoam is a lightweight and long-lasting substance that has become increasingly popular to repair damaged seawalls.
Related Research Articles
Polyurethane refers to a class of polymers composed of organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane is produced from a wide range of starting materials. This chemical variety produces polyurethanes with different chemical structures leading to many different applications. These include rigid and flexible foams, and coatings, adhesives, electrical potting compounds, and fibers such as spandex and polyurethane laminate (PUL). Foams are the largest application accounting for 67% of all polyurethane produced in 2016.
Flooring is the general term for a permanent covering of a floor, or for the work of installing such a floor covering. Floor covering is a term to generically describe any finish material applied over a floor structure to provide a walking surface. Both terms are used interchangeably but floor covering refers more to loose-laid materials.
In materials science, a thermosetting polymer, often called a thermoset, is a polymer that is obtained by irreversibly hardening ("curing") a soft solid or viscous liquid prepolymer (resin). Curing is induced by heat or suitable radiation and may be promoted by high pressure or mixing with a catalyst. Heat is not necessarily applied externally, and is often generated by the reaction of the resin with a curing agent. Curing results in chemical reactions that create extensive cross-linking between polymer chains to produce an infusible and insoluble polymer network.
Lamination is the technique/process of manufacturing a material in multiple layers, so that the composite material achieves improved strength, stability, sound insulation, appearance, or other properties from the use of the differing materials, such as plastic. A laminate is a permanently assembled object created using heat, pressure, welding, or adhesives. Various coating machines, machine presses and calendering equipment are used.
A structural insulated panel, or structural insulating panel, (SIP), is a form of sandwich panel used in the construction industry.
Hydroxyl-terminated polybutadiene (HTPB) is an oligomer of butadiene terminated at each end with a hydroxyl functional group. It reacts with isocyanates to form polyurethane polymers.
Memory foam consists mainly of polyurethane with additional chemicals that increase its viscosity and density. It is often referred to as "viscoelastic" polyurethane foam, or low-resilience polyurethane foam (LRPu). The foam bubbles or ‘cells’ are open, effectively creating a matrix through which air can move. Higher-density memory foam softens in reaction to body heat, allowing it to mold to a warm body in a few minutes. Newer foams may recover their original shape more quickly.
Insulating concrete form or insulated concrete form (ICF) is a system of formwork for reinforced concrete usually made with a rigid thermal insulation that stays in place as a permanent interior and exterior substrate for walls, floors, and roofs. The forms are interlocking modular units that are dry-stacked and filled with concrete. The units lock together somewhat like Lego bricks and create a form for the structural walls or floors of a building. ICF construction has become commonplace for both low rise commercial and high performance residential construction as more stringent energy efficiency and natural disaster resistant building codes are adopted.
Foam rubber refers to rubber that has been manufactured with a foaming agent to create an air-filled matrix structure. Commercial foam rubbers are generally made of synthetic rubber, natural latex or polyurethane. Latex foam rubber, used in mattresses, is well known for its endurance. Polyurethane is a thermosetting polymer that comes from combination of Methyl di-isocyanate and polyethylene and some other chemical additives.
Polyisocyanurate, also referred to as PIR, polyiso, or ISO, is a thermoset plastic typically produced as a foam and used as rigid thermal insulation. The starting materials are similar to those used in polyurethane (PUR) except that the proportion of methylene diphenyl diisocyanate (MDI) is higher and a polyester-derived polyol is used in the reaction instead of a polyether polyol. The resulting chemical structure is significantly different, with the isocyanate groups on the MDI trimerising to form isocyanurate groups which the polyols link together, giving a complex polymeric structure.
Hot-melt adhesive (HMA), also known as hot glue, is a form of thermoplastic adhesive that is commonly sold as solid cylindrical sticks of various diameters designed to be applied using a hot glue gun. The gun uses a continuous-duty heating element to melt the plastic glue, which the user pushes through the gun either with a mechanical trigger mechanism on the gun, or with direct finger pressure. The glue squeezed out of the heated nozzle is initially hot enough to burn and even blister skin. The glue is sticky when hot, and solidifies in a few seconds to one minute. Hot-melt adhesives can also be applied by dipping or spraying, and are popular with hobbyists and crafters both for affixing and as an inexpensive alternative to resin casting.
Wood glue is an adhesive used to tightly bond pieces of wood together. Many substances have been used as glues. Traditionally animal proteins like casein from milk or collagen from animal hides and bones were boiled down to make early glues. They worked by solidifying as they dried. Later, glues were made from plant starches like flour or potato starch. When combined with water and heated, the starch gelatinizes and forms a sticky paste as it dries. Plant-based glues were common for books and paper products, though they can break down more easily over time compared to animal-based glues. Examples of modern wood glues include polyvinyl acetate (PVA) and epoxy resins. Some resins used in producing composite wood products may contain formaldehyde. As of 2021, “the wood panel industry uses almost 95% of synthetic petroleum-derived thermosetting adhesives, mainly based on urea, phenol, and melamine, among others”.
Conformal coating is a protective, breathable coating of thin polymeric film applied to printed circuit boards (PCBs). Conformal coatings are typically applied at 25–250 μm to the electronic circuitry and provide protection against moisture and other harsher conditions.
Sealant is a substance used to block the passage of fluids through openings in materials, a type of mechanical seal. In building construction sealant is sometimes synonymous with caulk and also serve the purposes of blocking dust, sound and heat transmission. Sealants may be weak or strong, flexible or rigid, permanent or temporary. Sealants are not adhesives but some have adhesive qualities and are called adhesive-sealants or structural sealants.
Ducts are conduits or passages used in heating, ventilation, and air conditioning (HVAC) to deliver and remove air. The needed airflows include, for example, supply air, return air, and exhaust air. Ducts commonly also deliver ventilation air as part of the supply air. As such, air ducts are one method of ensuring acceptable indoor air quality as well as thermal comfort.
Building insulation materials are the building materials that form the thermal envelope of a building or otherwise reduce heat transfer.
Spray foam is a chemical product created by two materials, isocyanate and polyol resin, which react when mixed with each other and expand up to 30-60 times its liquid volume after it is sprayed in place. This expansion makes it useful as a specialty packing material which forms to the shape of the product being packaged and produces a high thermal insulating value with virtually no air infiltration.
Rigid panel insulation, also referred to as continuous insulation, can be made from foam plastics such as polyurethane (PUR), polyisocyanurate (PIR), and polystyrene, or from fibrous materials such as fiberglass, rock and slag wool. Rigid panel continuous insulation is often used to provide a thermal break in the building envelope, thus reducing thermal bridging.
Cementitious foam insulation is a cement-based thermal and acoustic insulation, with an R-value similar to that of fiberglass. It is installed as a foam with a consistency like shaving cream, or as pre-cast slabs. The current cost is similar to that of polyurethane foams.
Hydrogenated MDI (H12MDI or 4,4′-diisocyanato dicyclohexylmethane) is an organic compound in the class known as isocyanates. More specifically, it is an aliphatic diisocyanate. It is a water white liquid at room temperature and is manufactured in relatively small quantities. It is also known as 4,4'-methylenedi(cyclohexyl isocyanate) or methylene bis(4-cyclohexylisocyanate) and has the formula CH2[(C6H10)NCO]2.
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