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The Early History of Polymers

Synthetic polymer materials are so ubiquitous in modem life that we now take them for granted. But, the first commercially significant, completely synthetic plastic was only introduced at the beginning of the 20th century. This was Bakelite, invented by Leo Baekeland and a short account of his contributions will form the subject of one of our Polymer Milestones in the next chapter. The introduction of this new material was preceded by roughly 40 years of the development of what can be called semi-synthetics based on chemically modified forms of cellulose. [Pg.5]

I- I CURE 1-4 Articles made of Parkesine (Courtesy London Science Museum). [Pg.5]

Deutsches Museum) was gunpowder, but this produced so much smoke [Pg.6]


In tracing the origins of Imipolex G, Pynchon takes us deep into the early history of polymer science. The material is, he says,... [Pg.119]

Bom as a multi-disciplinary subject of chemistry and physics, polymer physics is also a bridge coimecting materials sciences and life sciences. At the early history of polymer science, many fundamental cmicepts of polymer physics were actually... [Pg.9]

The territory of an expanded single coil is much larger than the volume the monomers actually occupy. Therefore, in comparison to the collisions of small molecules, the probability of mutual collisions between two coils is significantly enhanced. When such fluffy coils diffuse, the mutual friction yields a solution with a high viscosity. In the early history of polymer science, the high viscous polymer solution was misimderstood as a colloidal gel. However, polymer solutions are actually the molecular dispersions of long chains in the solvent molecules. With the increase of the polymer concentration, the coils start to interpenetrate into each other. We can define an illusive critical overlap concentration C, as illustrated in Fig. 4.2. Then, polymer solutions with the concentrations beyraid C are called concentrated solutions. [Pg.45]

The early history of polymers is really the conversion of natural polymers into useful materials. Examples include the vulcanization of rubber (Goodyear, 1839), celluloid (which is plasticized cellulose nitrate—Hyatt, 1868), and cellulose-derived fibres, e.g. cuprammonia rayon (Despeisses, 1890) and viscose rayon (Cross, Bevan and Beadle, 1892). The first truly synthetic polymer, that is, one made from laboratory chemicals, was Bakelite (Bakeland, 1907). This was made from phenol and formaldehyde. Bakeland probably did not know the chemical structure of the Bakelite, but he did realize that organic chemicals containing multiple functionality yielded insoluble materials. The various phenol-formaldehyde resins (PF), e.g. Bakelite and novolacs, were thus obtained in an empirical manner. [Pg.3]

Many other parepistemes were stimulated by the new habits of precision in theory. Two important ones are the entropic theory of rubberlike elasticity in polymers, which again reached a degree of maturity in the middle of the century (Treloar 1951), and the calculation of phase diagrams (CALPHAD) on the basis of measurements of thermochemical quantities (heats of reaction, activity coefficients, etc.) here the first serious attempt, for the Ni-Cr Cu system, was done in the Netherlands by Meijering (1957). The early history of CALPHAD has recently been... [Pg.197]

In the early history of PVC, application was confined almost entirely to highly plasticized and flexible compositions, and the thermal processing liability of such formulations was practically the only question. Minimal mechanical shear work was applied to the polymer itself. Concomitant with the growth of the industry was the discovery that certain metal soaps... [Pg.53]

There is much to learn and admire in the hindered amine story. Chemists can take pride in how effectively they have worked together across national boundaries to make hindered amine stabilizers an important product group for the stabilization of polymers. This introduction is a modest effort to review some of the early history of stable-free radicals including triacetoneamine-N-oxyl. This chapter was intended to serve primarily as an introduction to the hindered amine review which took place at the symposium and intentionally avoids covering material which other participants were expected to present. It is a "light-touch" overview. [Pg.1]

Some polymers are easier to foam than others. Indeed, it was not until methods were found to circumvent the inclusion of cells in the early history of the phenol formaldehyde polymer that it gained any commercial significance. The development of foamed phenolic resins only became important much later when a specific need arose to produce rigid foam with reduced flammability. This consideration also led to the development of polyisocya-nurate foams and carbodiimide foams. On the other hand, the polypropylene family of polymers, although having a tonnage far exceeding that of phenol formaldehyde resins, is... [Pg.376]

John Millar was kind enough to amplify the early history of IPNs. He wrote that the original term for IPNs was reswollen polymer networks, ... [Pg.7]

During the past two decades, the alkene metathesis reaction has developed from its early appUcations in large-scale processes with heterogeneous and ill-defined catalyst systems to a standard technique in synthetic chemistry and polymer laboratories. The development of well-defined and often bench-stable precatalysts " has been key to the widespread use of alkene metathesis in modem target synthesis projects. The impact of this useful reaction was recognized in 2005 by the award of the Nobel Prize in Chemistry to Yves Chauvin, Robert Gmbbs, and Richard Schrock. Astmc has published an excellent article on the early history of the alkene metathesis reaction, which covers the determination of the mechanism and the rejection of alternative hypotheses, so this early history will not be discussed here. [Pg.82]

The use of fillers in pol3uners has been going on for years. In the early history of filled pol5oners, fillers were added to the polymers rather empirically. Woodflour was one of the first fillers used in thermosetting phenol-formaldehyde resins because the combination was found to be valuable in enhancing certain properties whereas the addition of some other finely divided material to such resins conferred no benefit at all and hence was never done. The presence of the woodflour increased... [Pg.23]

In the early history of polypropylene technology, blends with ethylene propylene copolymer were introduced for toughening polypropylene. Subsequently block copolymers of polypropylene with random ethylene propylene copolymer rubber were produced in the polymerization reaction. Dynamic vulcanization of ethylene propylene terpolymer in blends with polypropylene together with hydrocarbon oils was a third technology. The first TPO was elastomer (ethylene)-modified propylene (EP polymer) marketed to overcome polypropylene s weakness that cold temperature negatively impacts resistance. [Pg.225]

The history of polymer fire retardance is reviewed from its inception with the early Egyptians to the most recent developments in intumescent fire retardants and inherently fire retardant polymers. [Pg.87]

Armand (1994) has briefly summarised the history of polymer electrolytes. A more extensive account can be found in Gray (1991). Wakihara and Yamamoto (1998) describe the development of lithium ion batteries. Sahimi (1994) discusses applications of percolation theory. Early work on conductive composites has been covered by Norman (1970). Subsequent edited volumes by Sichel (1982) and Bhattacharya (1986) deal with carbon- and metal-filled materials respectively. Donnet et al. (1993) cover the science and technology of carbon blacks including their use in composites. GuF (1996) presents a detailed account of conductive polymer composites up to the mid-1990s. Borsenberger and Weiss (1998) discuss semiconductive polymers with non-conjugated backbones in the context of xerography. Bassler (1983) reviews transport in these materials. [Pg.305]


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