Polyurethane foam rollers

The low hardness has led to uses in printers rollers and stereos. It is, however, to be noted that when the material has been used to replace cellular rubbers or flexible polyurethane foams in sealing applications, problems have arisen where it has not been appreciated that although the rubber is very soft it is for practical purposes incompressible. 

The PUF roller technique consists of placing a cylinder of polyurethane foam (PUF) onto a weighted, stainless steel roller and then rolling it over a defined area of treated turf. The turf is typically rolled over three times. The PUF is then pulled off the weighted, stainless steel roller, extracted, and analyzed for residues. 

Toluene is a primary feedstock used to produce various organic compounds. It is used to produce diisocyanates. Isocyanates contain the functional group —N = C = O, and diisocyanates contain two of these. The two main diisocyanates are toluene 2,4-diisocyanate and toluene 2,6-diisocyanate. The production of diisocyanates in North America is close to a billion pounds annually. More than 90% of toluene diisocyanate production is used for making polyurethanes foams. The latter are used as flexible fill in furniture, bedding, and cushions. In rigid form it is used for insulation, hard shell coatings, building materials, auto parts, and roller skate wheels. 

FIGURE 2.16 Nip rollers for forcing prepolymer emulsion into reticulated polyurethane foam web. 

Polyurethane elastomer Roller skate wheels, sport arena floors, ski boots, automotive seats (foamed), shoe soles (foamed), etc. 

Consider the procedure for immobilizing an enzyme using polyurethane technology. A solution of the enzyme is produced in water. The solution is then emulsified with a hydrophilic polyurethane prepolymer. The emulsion is applied to the structural members of a reticulated foam by means of nip rollers. After curing... 

Polyurethanes are part of a very versatile group of materials that find uses in a wide range of applications, both domestic and industrial. Polyurethanes are widely used in many applications such as paints and lacquers, foam mattresses, medical implants, and industrial applications such as rollers, electrical encapsulation, engineering components, shoe soles, seals, and in the mining industry. 

In the absence of foaming, we can produce a material hard enough for roller blade wheels or soft and pliable enough to mimic leather. In fact, at the New York World s Fair of 1964, DuPont proudly introduced shoes made of Corfam, a polyurethane-based synthetic leather. The shoes were durable and waterproof, and they could be cleaned with a moist cloth. Best of all, Corfam was porous, so the shoes breathed like leather. Within a year, seventy-five million pairs of Corfam shoes had been sold, and the leather industry stopped breathing. But the Corfam fad didn t last. Despite the material s porosity, many complained of hot, sweaty feet, and furthermore, women didn t like the idea of shoes that lasted forever — they wanted new styles every year. So, Corfam became DuPont s Edsel. 

Liquid rubber technology has largely stemmed from the development of the polyurethanes. These materials were first produced in the 1930s in fibre form in an attempt to circumvent the Du Pont patents on the nylons. During World War II this led on to the solid Vulkollan rubbers and subsequently to the rigid and flexible foams. Modern processes can be adapted for such disparate products as car tyres, car body parts and soft, printers rollers. Such technology owes little to the traditional methods of the rubber industry. 

Almost all types of products currently made with polyurethanes can be made in rubber particle/polyurethane composites. Examples include molded wheels and rollers, adhesives, sealants, coatings and flexible foam. 

A number of different types of end-products, molded in treated rubber/ polyurethane, have been developed and commercialized. These include rollers, wheels, flexible foams, molded goods, coatings, adhesives and sealants. It is obvious that this is just the beginning and that a large number of additional uses will be developed in the future. 

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