Poly Urethene Coatings
Polyurethane is a unique material that offers the elasticity of rubber combined with the toughness and durability of metal. Because urethane is available in a very broad hardness range (eraser-soft to bowling-ball-hard), it allows the engineer to replace rubber, plastic and metal with the ultimate in abrasion resistance and physical properties. Polyurethane can reduce plant maintenance and OEM product cost. Many applications using this ultra-tough material have cut down-time, maintenance time and cost of parts to a fraction of the previous figures.
Urethanes have better abrasion and tear resistance than rubbers, while offering higher load bearing capacity.
Compared to plastics, urethanes offer superior impact resistance, while offering excellent wear properties and elastic memory
Urethanes have replaced metals in sleeve bearings, wear plates, sprockets, rollers and various other parts, with benefits such as weight reduction, noise abatement and wear improvements being realized.
How Is Polyurethane Made?
Polyurethanes are formed by reacting a polyol (an alcohol with more than two reactive hydroxyl groups per molecule) with a diisocyanate or a polymeric isocyanate in the presence of suitable catalysts and additives.
Because a variety of diisocyanates and a wide range of polyols can be used to produce polyurethane, a broad spectrum of materials can be produced to meet the needs of specific applications.
Most polyurethanes are thermoset materials; they cannot be melted and reshaped as thermoplastic materials can be.
Polyurethanes exist in a variety of forms including flexible foams, rigid foams, chemical-resistant coatings, specialty adhesives and sealants, and elastomers.
Rigid polyurethane foams are used as insulation for buildings, water heaters, refrigerated transport, and commercial and residential refrigeration. These foams are also used for flotation and for energy management.
Polyurethane is an incredibly resilient, flexible, and durable manufactured material that can take the place of paint, cotton, rubber, metal, and wood in thousands of applications across all fields. Polyurethane might be hard, like fiberglass, squishy like upholstery foam, protective like varnish, bouncy like rubber wheels, or sticky like glue.
Polyurethane is a substance categorized as a polymer based on its chemical structure. One manufacturers polyurethane by combining a diisocyanate and a diol, two monomers, through a chemical reaction. This makes a basic material whose variations can be stretched, smashed, or scratched, and remain fairly indestructible. Depending on the different diisocyanates and diol or polyol constituents, the resulting polyurethane might take a liquid, foam, or solid form, each with advantages and limitations.
ex:Belts, Metal forming pads, Wear strips, Bumpers, Gears, Bellows, Machinery mounts, Cutting Surfaces, Sound-dampening pads, Chute and hopper liners, Prototype machined parts, Gaskets, Seals, Rollers, Roller covers, Sandblast curtains, Diaphragms
Polyurethane Coatings, Adhesives, Sealants and Elastomers (CASE)
Polyurethane coatings are applied to products to improve their appearance and lifespan. On cars, polyurethane coatings give the exterior a high gloss and improved color retention, while offering improved scratch- and corrosion-resistance.
Other types of polyurethane coatings are used in construction, where building floors, steel trusses and concrete supports are spray-coated to make them more durable and less costly to maintain. This coating, for example, makes a suspension bridge easier to clean, helps to keep its support beams from rusting, and improves its appearance even from a great distance.
Polyurethane Adhesives and Sealants
Polyurethane adhesives and sealants provide strong bonding and tight seals in a variety of applications. Polyurethane adhesives provide the advantage of a rapid development of "green strength," where the adhesive provides an initial bond before fully curing. This reduces the need for clamping and holding materials, thereby cutting costs and increasing manufacturing and construction flexibility.
Polyurethane adhesives are used in the assembly of shoes, automotive interiors, windshield bonding and as textile laminates. Conveyor belts are usually closed using polyurethane adhesives, and polyurethane binders are mixed with wood chips or saw dust to form fiberboard. Polyurethane sealants are used in road repair, plumbing, construction and anywhere else a high-strength, water-resistant seal is needed.
Polyurethane elastomers are rubber-like materials that can be created with a wide variety of properties and molded into almost any shape. Depending on the intended use, polyurethane elastomers can provide resistance to:
- impact and shock,
- cuts and tears,
- oil and solvents,
- mold, mildew and fungus, and
- most types of chemicals.
Characteristics of Poymers
The majority of manufactured polymers are thermoplastic, meaning that once the polymer is formed it can be heated and reformed over and over again. This property allows for easy processing and facilitates recycling. The other group, the thermosets, cannot be remelted. Once these polymers are formed, reheating will cause the material to ultimately degrade, but not melt.
Polymers can be very resistant to chemicals. Consider all the cleaning fluids in your home that are packaged in plastic. Reading the warning labels that describe what happens when the chemical comes in contact with skin or eyes or is ingested will emphasize the need for chemical resistance in the plastic packaging. While solvents easily dissolve some plastics, other plastics provide safe, non-breakable packages for aggressive solvents
Polymers can be both thermal and electrical insulators. A walk through your house will reinforce this concept, as you consider all the appliances, cords, electrical outlets and wiring that are made or covered with polymeric materials. Thermal resistance is evident in the kitchen with pot and pan handles made of polymers, the coffee pot handles, the foam core of refrigerators and freezers, insulated cups, coolers, and microwave cookware. The thermal underwear that many skiers wear is made of polypropylene and the fiberfill in winter jackets is acrylic and polyester.