Insulating foams

Monofunctional, cyclohexylamine is used as a polyamide polymerization chain terminator to control polymer molecular weight. 3,3,5-Trimethylcyclohexylamines ate usehil fuel additives, corrosion inhibitors, and biocides (50). Dicyclohexylamine has direct uses as a solvent for cephalosporin antibiotic production, as a corrosion inhibitor, and as a fuel oil additive, in addition to serving as an organic intermediate. Cycloahphatic tertiary amines are used as urethane catalysts (72). Dimethylcyclohexylarnine (DMCHA) is marketed by Air Products as POLYCAT 8 for pour-in-place rigid insulating foam. Methyldicyclohexylamine is POLYCAT 12 used for flexible slabstock and molded foam. DM CHA is also sold as a fuel oil additive, which acts as an antioxidant. StericaHy hindered secondary cycloahphatic amines, specifically dicyclohexylamine, effectively catalyze polycarbonate polymerization (73). 

Extruded Rigid Foa.m. In addition to low temperature thermal insulation, foamed PSs are used for insulation against ambient temperatures in the form of perimeter insulation and insulation under floors and in walls and roofs. The upside-down roof system has been patented (256), in which foamed plastic such as Styrofoam (Dow) plastic foam is appHed above the tar-paper vapor seal, thereby protecting the tar paper from extreme thermal stresses that cause cracking. The foam is covered with gravel or some other wear-resistant topping (see Roofing materials). 

The avadabihty of PMDI also led to the development of polyurethane-modified isocyanurate (PUIR) foams by 1967. The PUIR foams have superior thermal stabiUty and combustibiUty characteristics, which extend the use temperature of insulation foams well above 150°C. The PUIR foams are used in pipe, vessel, and solar panel insulation glass-fiber-reinforced PUIR roofing panels having superior dimensional stabiUty have also been developed. More recently, inexpensive polyester polyols based on residues obtained in the production of dimethyl terephthalate (DMT) have been used in the formulation of rigid polyurethane and PUIR foams. 

Thermal Insulation. Foamed plastics (qv) are used as thermal insulation for aU types of constmction because of their low heat- and moisture-transmission values. Polystyrene is used either as foamed board or expandable beads. The foam may be faced with a stmctural surfacing material, eg, a kraft liner-board, to form a panel for insulating mobile homes. These foams can dupHcate the appearance of wood and be used as trim. Foams can also be used as backing, for example, on aluminum siding, to provide heat and sound insulation. Foamed beads can be incorporated in concrete to reduce its density and provide some thermal insulation. 

Formaldehyde Outgassing of pressed wood, insulation foam... 

The law requires nonessential products releasing Class 1 chemicals to be banned within 2 years of enactment. In 1994 a ban wiU go into effect for aerosols and non-insulating foam using Class II chemicals, with exemptions for flammability and safety. Regulations for this purpose will be required within one year of enactment, to become effective tv o vears afterwards. 

Cryogenic Polyurethane Insulative foam for cryogenic tankage... 

These coatings bubble and foam to form a thermal insulation when subjected to a fire. They have been used for many decades. Such coatings cannot be differentiated from conventional coatings prior to the occurrence of a fire situation. Thereupon, however, they decompose to form a thick, nonflammable, multicellular, insulative barrier over the surface on which they are applied. This insulative foam is a very effective insulation that maintains the temperature of a flammable or heat distortable substrate below its ignition or distortion point. It also restricts the flow of air (oxygen) to fuel the substrate. 

Rigid insulation foam, 206 Rigid isocyanurate foams, 226 RIM. See Reaction injection molding (RIM)... 

Methylenedianiline is used to make an intermediate in the manufacture of polyurethane rubber used for making automobile parts, shoe soles, rubber wheels, and insulation foam. 

Phenol-formaldehyde (PF) resins were synthesized to manufacture non-flammable insulating foam. When alkali catalyst, for example, barium hydroxide (Ba(OH)2), was present, lesol resins are produced[l]. In the analj s of molecular species of resol, capillary GC-MS had been used to separate hemiformal-type compoimds(acetylated hydroxybenzylhaniformals)... 

When used purely as an insulator, foam densities can be as low as 0.02 to 0.08 g/cm3. In structural applications the foam s density can rise to 0.4 to 0.7 g/cm3. The use of fluorocarbons as blowing agents has largely given way to more environmentally friendly agents, such as low molecular weight hydrocarbons. We can impart flame retardancy by incorporating chlorine-or phosphorus-based compounds. 

CFC-based blowing agents used to date in the production of PE insulating foam must be replaced by alternative... 

HCFC-141b replaced CFC-11 as the blowing agent in insulating foams. 

In recent years, blown oils have found their way into the polyurethane industry. The additional hydroxyl content introduced through the oxidation process makes the oils more reactive toward isocyanates [82]. The oils can usually be incorporated at low levels into conventional formulations with little compromise to the mechanical properties of the finished polyurethanes. Blown oils have since found utility in carpet backing, insulation foams, and other polyurethane products [83]. At least a... 

Solid foam—expanded (polystyrene) Insulating foam... 

Packaging and insulation foams, lighting panels, appliance and furniture components, egg cartons... 

---