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.
Polyurethane formulations cover an extremely wide range of stiffness, hardness, and densities. These materials include:
Crown Rubber Works is Leading Premium Quality Polyurethane Products Manufacturer and Exporter from India.
The classification of hardness for polyurethane relies on the prepolymer's molecular structure and can be manufactured from 20 SHORE A to 85 SHORE D
Polyurethane has a high load capacity in both tension and compression. Polyurethane may undergo a change in shape under a heavy load, but will return to its original shape once the load is removed with little compression set in the material when designed properly for a given application.
Polyurethanes perform very well when used in high flex fatigue applications. Flexural properties can be isolated allowing for very good elongation and recovery properties.
For applications where severe wear prove challenging, polyurethanes are an ideal solution even at low temperatures.
Polyurethanes possess high tear resistance along with high tensile properties.
Polyurethane's material properties will remain stable (with minimal swelling) in water, oil and grease. Polyether compounds have the potential to last many years in subsea applications.
Polyurethanes exhibit good electrical insulating properties.
Resilience is generally a function of hardness. For shock-absorbing elastomer applications, low rebound compounds are usually used (i.e. resilience range of 10-40%). For high frequency vibrations or where quick recovery is required, compounds in the 40-65% resilience are used. In general, toughness is enhanced by high resilience.
Polyurethane bonds to a wide range of materials during the manufacturing process. These materials include other plastics, metals and wood. This property makes polyurethane an ideal material for wheels, rollers and inserts.
Polyurethane is very resistant to extreme temperature, meaning harsh environmental conditions and many chemicals rarely cause material degradation.
Most polyether based polyurethanes do not support fungal, mold and mildew growth and are therefore highly suitable for tropical environments. Special additives can also be added to reduce this in polyester materials as well.
Varying color pigments can be added to polyurethane in the manufacturing process. Ultraviolet shielding can be incorporated into the pigment to provide better color stability in outdoor applications.
Polyurethane is often used to manufacture one-off parts, prototypes or high volume, repeat production runs. Size ranges vary from a couple grams to 2000lb parts.
Compared to conventional thermoplastic materials polyurethane has a relatively short lead time with significantly more economical tooling costs.
Advantages of Polyurethane Material
|Polyurethane vs. Rubber||Polyurethane vs. Metal||Polyurethane vs. Plastic|
|High abrasion resistance||Lightweight||High impact resistance|
|High cut & tear resistance||Noise reduction||Elastic memory|
|Superior load bearing||Abrasion resistance||Abrasion resistance|
|Thick section molding||Less expensive fabrication||Noise reduction|
|Colorability||Corrosion resistance||Variable coefficient of friction|
|Ozone resistance||Impact resistance||Thick section molding|
|Radiation resistance||Flexibility||Lower cost tooling|
|Broader hardness range||Easily moldable||Low temperature resistance|
|Castable nature||Non-conductive||Cold flow resistance|
|Low pressure tooling||Non-sparking||Radiation resistance|