Dunlop

For reviews on furan chemistry see References 1, 4—7. The monograph by Dunlop and Peters (1), pubHshed in 1953 remains as the most comprehensive review of furan chemistry available. Unfortunately, it has never been revised, has been out of print for many years, and is not readily available. An excellent, review by Dean (7) covers advances in furan chemistry up through about 1982. 

A. P. Dunlop and F. N. Peters, TheEurans, ACS Monograph 119, Reinhold PubUshing Corp., New York, 1953. 

The earhest frothing process developed was the Dunlop process, which made use of chemical gelling agents, eg, sodium fluorosiUcate, to coagulate the mbber particles and deactivate the soaps. The Talalay process, developed later, employs freeze-coagulation of the mbber followed by deactivation of the soaps with carbon dioxide. The basic processes and a multitude of improvements are discussed extensively in Reference 3. A discussion more oriented to current use of these processes is given in Reference 115. 

Many different processes are patented for preparing latex foam but only two are of commercial interest for preparing molded cushioning stock the Dunlop, which is most widely used, and the Talalay processes. Some producers have developed variations, which are combinations of the two processes. 

The latex may consist entirely of natural latex or synthetic SBR latex or maybe a mixture of both. In the Dunlop process, natural mbber foams shrink more than SBR foams duriag washing and dryiag. The load-beariag capacity of the foams at a given density falls significantly as SBR is used ia place of natural mbber. 

In the Talalay process, the froth is produced by chemical rather than mechanical means. Hydrogen peroxide and an enzyme decomposition catalyst are mixed iato the latex and the mixture placed ia the mold. Decomposition of the peroxide by the added enzyme results ia the Hberation of oxygen which causes the latex mix to foam and fill the mold. The foam is then rapidly chilled and CO2 is iatroduced to gel the latex. The gelled foam is then handled ia a manner similar to that used ia the Dunlop process. 

P. Dunlop and co-workers, "Aqueous Surfactant Solutions Which Exhibit Ultra-Low Tensions at the Oil-Water Interface," Paper presented at the... 

Scottish inventor ]chn Boyd Dunlop, displays an invention he patented in 1888—the bicycle with pneumatic tires. (Corbis-Betlmann)... 

The first commercially successful pneumatic tire was developed in 1888 in Belfast by the Scottish veterinarian John Boyd Dunlop primarily to improve the riding comfort of bicycles. Dunlop also showed, albeit qualitatively, that his air-inflated pneumatic took less effort to rotate than did the solid rubber tires in use at that time. His qualitative tests were the first known rolling resistance experiments on pneumatic tires. Due to this significant reduction in rolling loss, many professional cyclists in Britain and Ireland adopted air-inflated tires for their bicycles by the early 1890s. Pneumatics for the nascent automobile industry soon followed. 

Tires, like everything that rolls, encounter resistance. The resistance encountered by the tire rolling across a surface is a major factor in determining the amount of energy needed to move vehicles. Since Dunlop s original efforts, a considerable number of tire design improvements have been made that have tended to cause a decrease in tire power consumption. For example separate plies of cotton cord were intro-... 

Scottish inventor John Boyd Dunlop creates an air-inflated rubber tire. 

Most theoretical studies have concentrated on the analysis of the combustion zone of nonaluminized propellant systems. In actual practice, propellants containing aluminum are used in many applications. One study in which aluminum has been included has recently been published by Dunlop and Crowe (D2). In this study, the combustion zone is idealized to consist of four regions, as shown in Fig. 21. The results of these simplified one-dimensional analyses suggest that the combustion of aluminum particles in the gas... 

D2. Dunlop, R., and Crowe, C. T., Third Quart. Progr. Rept., Contract NOw 65-0222f, United Technology Center, Sunnyvale, California (September 1965). 

Dunlop EH, Namdev PK, Rosenberg MZ (1994) Chemical Engineering Science 49 2263... 

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