Applications flexible urethane

The largest volume use of phosphorus-based flame retardants may be in plasticized vinyl. Other use areas for phosphorus flame retardants are flexible urethane foants. polyester resins and other thermoset resins, adhesives. textiles. polycarbonate-ABS blends, and some Other thermoplastics. Development efforts are well advanced lo find applications for phosphorus flame retardants, especially ammonium polyphosphate combinations, in polyolefins, and red phosphorus in nylons, Interest is strong in finding phosphorus-bused alternatives to those halogen-containing systems which have encountered environmental opposition, especially in Europe. 

Aryl phosphates were introduced into commercial use early in the twentieth century for flammable plastics such as cellulose nitrate and later for cellulose acetate.26 In vinyls (plasticized), arylphos-phates are frequently used with phthalate plasticizers. Their principal applications are in wire and cable insulation, connectors, automotive interiors, vinyl moisture barriers, plastic greenhouses, furniture upholstery, and vinyl forms. Triarylphosphates are also used, on a large scale, as flame-retardant hydraulic fluids, lubricants, and lubricant additives. Smaller amounts are used as nonflammable dispersing media for peroxide catalysts. Blends of triarylphosphates and pentabromodiphenyl oxide are extensively used as flame-retardant additives for flexible urethane foams. It has been also... 

Use is made of integral skin foams. They are flexible urethane foams with a high density skin. They are used in applications such as steering wheels, arm rests, and protective covers that must combine a tough surface and a soft feel. 

Uses ANTIBLAZE 78 flame retardant is highly effective for rigid and flexible urethanes, bonded foam, semi-durable textile applications and phenolic-based laminates. 

Classification. Flexibie urethane foams have the largest market of all polyurethane products. The production properties and applications of various flexible urethane foams are described in the following sections. Flexible urethane foams are defined as open-cell urethane foams having the property of complete recovery immediately after compression. They can be classified into two kinds, i.e., polyether foams and polyester foams. Polyether foams are further classified as follows conventional flexible foams, high-resilience flexible foams (HR foams), cold-molded foams, super-soft foams, and viscoelastic foams. 

Applications of Fiexible Urethane Foams. Cushioning materials are the major applicatioii of flexible urethane foams. In 1980, the worldwide consumption of urethane foams was as follows (48) furniture and mattress applications, 37% and automotive applications, 18%. In addition to these applications, a wide variety of additional applications have been reported, including transportation, textiles, packaging, appliances, household materials, medical supplies, sound absorbents, sporting goods, cosmetics, agricultural applications such as artificial soil, and toys. 

BS 3379 1975 Specification iot Flexible Urethane Foam for Loadbearing Applications (incorporates Amendment 1, April 1978), 16 pp... 

Flexible urethane foam for furniture applications is the largest single end use accounting for an estimated 37% last year. Consumption of foam in furniture vas estimated to be flat last year and is expected to decline in 1980. This should be followed by strong growth years in 1981-83 which we are estimating at 1-9% per year (see below). 

This forecast assumes that the furniture segment is fully penetrated by flexible urethane foam. Style changes may impact cushion dimensions somewhat, but are considered an insignificant factor in the forecast. Flammability issues remain unsettled however, this forecast assumes technology development will continue to keep urethane foam in the forefront as the best choice for cushioning applications. 

The growth in vaterbed production has had a positive impact on urethane foam demand. Boarder or dam components made from a firm, high density flexible urethane foam has bouyed foam consumption in bedding despite foams lack of growth in other bedding applications, i.e. foam cores and topper pads. 

The topper pad application for urethane receives strong competition from garneted cotton felt pads. The mattress industry continuously evaluates the relative cost and consumer acceptance of the two alternative padding materials. Utilization of flexible urethane foam and the relative share of the available topper pad volume appears to cycle with the competitive price pressures perceived to exist in the retail mattress market. When mattress prices weaken due to slack demand, mattress manufacturers appear willing to cut costs at the expense of consumer comfort and consequently shift a higher ratio of production to cotton felt. 

As a model system, a conventional flexible urethane foam formulation developed by Union Carbide for automotive seat applications has been used. It consists of ... 

Methylene chloride is a widely used chemical solvent with a diverse number of applications. It was introduced as a replacement for more flammable solvents over 60 years ago. Methylene chloride is commonly used in paint removers and industrial adhesive formulations. It also is employed in the production of flexible urethane foams, pharmaceutical products, and plastics, as a cleaning agent for fabricated metal parts, and as an extraction solvent. 

Moisture-curable urethane systems (one-pack) can be considered as two-component systems which use atmospheric moisture as the second component. One-pack urethane coatings can be produced that are similar in physical properties to the two-pack systems for almost all applications. These highly complex systems can have a great deal of flexibility. Claimed advantages are a one-pack system, rapid cure, even at low temperatures, excellent chemical and abrasion resistance and good flexibility. Although these systems have been available for some time in other countries of Europe, they are only recently beginning to be of interest in the UK. 

Flexible foams are used in applications where a high degree of resiliency is required with moderate load-bearing capacity. Essentially all foam seating is urethane based, including the furniture and automotive markets. Other examples are packaging, textiles, filters, sports equipment, and recreational items. 

Hydrosilation reactions have been one of the earlier techniques utilized in the preparation of siloxane containing block copolymers 22,23). A major application of this method has been in the synthesis of polysiloxane-poly(alkylene oxide) block copolymers 23), which find extensive applications as emulsifiers and stabilizers, especially in the urethane foam formulations 23-43). These types of reactions are conducted between silane (Si H) terminated siloxane oligomers and olefinically terminated poly-(alkylene oxide) oligomers. Consequently the resulting system contains (Si—C) linkages between different segments. Earlier developments in the field have been reviewed 22, 23,43> Recently hydrosilation reactions have been used effectively by Ringsdorf 255) and Finkelmann 256) for the synthesis of various novel thermoplastic liquid crystalline copolymers where siloxanes have been utilized as flexible spacers. Introduction of flexible siloxanes also improved the processibility of these materials. 

In addition to its use in PTT, 1,3-propanediol can replace traditional glycols in urethane-based polymer systems, improving thermal and hydrolytic stability. As a partial substitute for traditional glycols in polyester systems, 1,3-propanediol can improve coating flexibility without affecting other key properties. Other applications include engine coolants and water-based inks (33). 

In the manufacture of highly resilient flexible foams and thermoset RIM elastomers, graft or polymer polyols are used. Graft polyols are dispersions of free-radical-polymerized mixtures of acrylonitrile and styrene partially grafted to a polyol. Polymer polyols are available from BASF, Dow, and Union Carbide. In situ polyaddition reaction of isocyanates with amines in a polyol substrate produces PHD (polyhamstoff dispersion) polyols, which are marketed by Bayer (21). In addition, blending of polyether polyols with diethanolamine, followed by reaction with TDI, also affords a urethane/urea dispersion. The polymer or PHD-type polyols increase the load bearing properties and stiffness of flexible foams. Interreactive dispersion polyols are also used in RIM applications where elastomers of high modulus, low thermal coefficient of expansion, and improved paintability are needed. 

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