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The word "polymer" (first proposed by Berzelius in 1833) is made of "poly" from the ancient Greek word "mlvq" meaning "many" and "pepot " meaning "part". Polymers are molecules built up from numerous identical chemical "units" spatially repeated to form a chain. From the early times and still nowadays, a distinction is often made between "natural" and "synthetic" polymers, but it is somewhat artificial as natural polymers can now sometimes be synthesized (e.g., synthetic "natural rubber") and some synthetic polymers, which are never found in nature, can be synthesized by natural ways (enzymatic syntheses). 

They are called didepsides, tridepsides, poly-depsides, etc., depending on the number of phenol residues they contain. Obtained from lichens, present in tea. 

CHR) , formed, e g. from the reaction of diazomethane and alcohols or hydroxylamine derivatives in the presence of boron compounds or with metal compounds. Poly-methylene is formally the same as polyethene and the properties of the various polymers depend upon the degree of polymerization and the stereochemistry. 

Resins formed from the reaction of poly(vinyl alcohol) with aldehydes. The formal derivative (from methanal) is used in wire coatings and adhesives and the bulyral (from butanal) is used in metal paints, wood-sealers, adhesives and in safety glass interlayers. 

Prepared generally by ester interchange from polyvinylacelate (ethanoate) using methanol and base also formed by hydrolysis of the acetate by NaOH and water. The properties of the poly(vinyl alcohol) depend upon the structure of the original polyvinyl acetate. Forms copolymers. Used as a size in the textile industry, in aqueous adhesives, in the production of polyvinyl acetates (e.g. butynal) for safety glasses. U.S. production 1980... 

Organic polyesters, obtained either from a diacid and a mono-alcohoi, or from poly-alcohols and a monoacid, or from di-alcohols and a diacid. This class represented 29% of the synthetic base market in France in 1992. 

The reports were that water condensed from the vapor phase into 10-100-/im quartz or pyrex capillaries had physical properties distinctly different from those of bulk liquid water. Confirmations came from a variety of laboratories around the world (see the August 1971 issue of Journal of Colloid Interface Science), and it was proposed that a new phase of water had been found many called this water polywater rather than the original Deijaguin term, anomalous water. There were confirming theoretical calculations (see Refs. 121, 122) Eventually, however, it was determined that the micro-amoimts of water that could be isolated from small capillaries was always contaminated by salts and other impurities leached from the walls. The nonexistence of anomalous or poly water as a new, pure phase of water was acknowledged in 1974 by Deijaguin and co-workers [123]. There is a mass of fascinating anecdotal history omitted here for lack of space but told very well by Frank [124]. 

Fig. XI-7. Volume fraction profile of 280,000-molecular-weight poly(ethylene oxide) adsorbed onto deuterated polystyrene latex at a surface density of 1.21 mg/m and suspended in D2O, from Ref. 70.

Fig. XV-1. Plots of t/CRT vs. C for a fractionated poly(methyl acrylate) polymer at the indicated temperatures in degrees Celsius. [From A. Takahashi, A. Yoshida, and M. Kawaguchi, Macromolecules, 15, 1196 (1982) (Ref. 1). Copyright 1982, American Chemical Society.]...

As discussed in section A 1.2.17. the existence of the approximate poly ad numbers, corresponding to short-time bottlenecks to energy flow, could be very important in efforts for laser control, apart from the separate question of bifiircation phenomena. 

A graphical method, proposed by Zimm (thus tenned the Zinnn plot), can be used to perfomi this double extrapolation to detemiine the molecular weight, the radius of gyration and the second virial coefficient. An example of a Zinnn plot is shown in figure Bl.9.6 where the light scattering data from a solution of poly... 

Figure Bl.9.6. A typical Zinnn plot data obtained from a solution of poly (tetrafliioroethylene) (PTFE) M =...

Figure Bl.19.30. Height and friction images of a spin-cast polystyrene-poly(methyl methacrylate) blend obtained with (a) gold and (b) silica probes under perfluorodecalin. Note the reversal of frictional contrast and the high spatial resolution. (Taken from [142], figure 7.)...

Several studies have demonstrated the successful incoriDoration of [60]fullerene into polymeric stmctures by following two general concepts (i) in-chain addition, so called pearl necklace type polymers or (ii) on-chain addition pendant polymers. Pendant copolymers emerge predominantly from the controlled mono- and multiple functionalization of the fullerene core with different amine-, azide-, ethylene propylene terjDolymer, polystyrene, poly(oxyethylene) and poly(oxypropylene) precursors [63,64,65,66,62 and 66]. On the other hand, (-CggPd-) polymers of the pearl necklace type were fonned via the periodic linkage of [60]fullerene and Pd monomer units after their initial reaction with thep-xy y ene diradical [69,70 and 71]. 

Silicon is used in many fonns, from high-purity tliin films to bulk material, which may be crystalline, multi- or poly crystalline and amorjDhous (usually hydrogenated). Silicon is the material discussed tire most in tliis article. Substitutional B and P are tire most common (of many) shallow acceptors and donors, respectively. 

N-Benzylamides are recommended when the corresponding acid is liquid and/or water-soluble so that it cannot itself serve as a derivative. Phe benzylamides derived from the simple fatty acids or their esters are not altogether satisfactory (see Table below) those derived from most hydroxy-acids and from poly basic acids or their esters are formed in good yield and are easily purified. The esters of aromatic acids yield satisfactory derivatives but the method must compete with the equally simple process of hydrolysis and precipitation of the free acid, an obvious derivative when the acid is a solid. The procedure fails with esters of keto, sul phonic, inorganic and some halogenated aliphatic esters. 

These may be produced from a great variety of poly-functional compounds to obtain satisfactory products, the reactants must be pure. A few examples follow. 

When dealing with esters of water-soluble, non steam-volatile, poly-hydric alcohols e.g., ethylene glycol or glycerol), the distillate consists of water only (density 1 00). The water soluble, non-volatile alcohol may be isolated by evaporation of the alkahne solution to a thick syrup on a water bath and extraction of the polyhydric alcohol from the salt with cold ethyl alcohol. 

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