Integral skin molding

Semiflexible molded polyurethane foams are used in other automotive appHcations, such as instmment panels, dashboards, arm rests, head rests, door liners, and vibrational control devices. An important property of semiflexible foam is low resiHency and low elasticity, which results in a slow rate of recovery after deflection. The isocyanate used in the manufacture of semiflexible foams is PMDI, sometimes used in combination with TDI or TDI prepolymers. Both polyester as well as polyether polyols are used in the production of these water-blown foams. Sometimes integral skin molded foams are produced. 

See also one-shot molding, isocyanate, polyol, polyether foam, reticulated polyurethane foam, and integral-skin molding. 

Integral-Skin Molding n A method of producing urethane-foam articles with substantially nonporous... 

The sandwich-type stmcture of polyurethanes with a smooth integral skin produced by the reaction injection molding process provides a high degree of stiffness as weU as exceUent thermal and acoustical properties necessary for its use in housing and load-bearing stmctural components for the automotive, business machine, electrical, furniture, and materials-handling industry. 

The rigid urethane foam concept with integral skins has also found considerable interest in the automotive industry for exterior body parts, such as engine or trunk compartment lids, fenders and even full roofs. These parts can be reinforced with metal inserts where necessary or hinges and fasteners can be molded in for ready mounting. 

Here, the case of free rise in an open mold is analyzed. Because of the very low thermal conductivity of a plastic foam, an adiabatic process will be considered. The nonadiabatic case in a closed mold leads to integral-skin foams. These foams exhibit a mass density gradient, with unfoamed skins in contact with the mold walls (Marciano et al., 1986). 

Aqualease. [Gemge Mann] Silicone emulsions release scents for casting molds, cast urediane elastomer and integral skin urethane foams, epoxies, filled polyester, vinyl ester resins. 

Flenpol . [Flexible Prods.] Rigid or flexible polyurethane systems for decorative molding, flotation, furniture, walk-in refrigeration, water heater, acoustic, pkg toys, seats and cushioning, integral skin applies. 

Structural foam is the term usually used for foam produced in an injection molding press and made of almost many thermoplastic resin. Structural foam is always produced with a hard integral skin on the outer surfaces and a cellular core in the interior, and is used almost exclusively for production of molded parts. The process is thus ideally suited for fabrication of parts such as business machine housings (commonly for ABS), and similar parts or components in which lightweight and stiffness are required. 

High-density rigid foam, 5—15 Ib/ft (0.08-0.24 g/cm ), is used for furniture items such as TV and stereo cabinets, chair shells, frames, arms, and legs, cabinet drawer fronts and doors, and mirror and picture frames. RIM-molded, integral-skin, high-density foams with core densities of 10—20 Ib/ft (0.16—0.32 g/cm ) and skin densities of 55-65 Ib/ft (0.88—1.04 g/cm are used in electronic, instrument, and computer cabinets. 

Replacement of upper mold half — PP integral skin foam still a long way from satisfying current standards... 

Integral skin PUR foams are made by injecting the reactants into a closed (vented) or open mold. Reaction under fliese conditions produces a foam with a high-density outside skin layer and a soft foam interior. Common products such as steering wheels, footwear components, and computer housings generally employ integral skin PUR foams. 

In flexible slabstock and molded polyurethane foam production, methylene chloride, CO2 (liquid or gas injection), and water are used as ABAs. In rigid insulation foams CFCs have been replaced with HFC-134a (sometimes blended with HFC 152a) or liquid CO2. In integral skin polyurethane products, CO2, water, and hydrocarbons are used for the purpose. 

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