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An assortment of polyurethane foam products for cushioning and insulation. Polyurethane foam is a solid polymeric foam based on polyurethane chemistry. As a specialist synthetic material with highly diverse applications, polyurethane foams are primarily used for thermal insulation and as a cushioning material in mattresses, upholstered furniture or as seating in vehicles.
The methods of manufacturing polyurethane finished goods range from small, hand pour piece-part operations to large, high-volume bunstock and boardstock production lines. Regardless of the end-product, the manufacturing principle is the same: to meter the liquid isocyanate and resin blend at a specified stoichiometric ratio, mix them together ...
Spray foam insulation or spray polyurethane foam (SPF) is an alternative to traditional building insulation such as fiberglass. A two-component mixture composed of isocyanate and polyol resin comes together at the tip of a gun, and forms an expanding foam that is sprayed onto roof tiles, concrete slabs, into wall cavities, or through holes ...
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.
The effects are temperature-dependent, so the temperature range at which memory foam retains its properties is limited. If it is too cold, it hardens. If it is too hot, it acts like conventional foams, quickly springing back to its original shape. The underlying physics of this process can be described by polymeric creep. [2] [3]
Thermoplastic polyurethane (TPU) is any of a class of polyurethane plastics with many properties, including elasticity, transparency, and resistance to oil, grease, and abrasion. Technically, they are thermoplastic elastomers consisting of linear segmented block copolymers composed of hard and soft segments.
A range of NCO/OH eq. ratios from 1.2 - 1.6 was used. Thermal and mechanical properties of moisture cured polyurethane-urea /clay nanocomposite coatings have been studied in relationship to clay dispersion and intercalation of clay platelets in the urethane-urea matrix. [ 4 ]
In dogs, the thermoneutral zone ranges from 20–30 °C (68–86 °F). [9] Domestic cats have a considerably higher thermoneutral zone, ranging between 30 and 38 °C. [10] In horses, the lower critical temperature is 5 °C while the upper critical temperature depends on the definition used. [11]