Polyphosphonate

Polyphosphonates are well-known flame-retardant materials [110] and are generally prepared by melt [111,112], interfacial [113-115] and solution polycondensation methods [116]. A typical example of synthesis is the polycondensation of bifunctional organophosphorus compounds, such as dichlorophenylphosphine oxide, with bisphenols [117,118]. 

Polyphosphonic acids are conveniently esterified by treatment with orthoformate esters with distillation of the lower-boiling alcohol. This procedure worked well for the acid (74), which readily dimerizes, and was also used to establish the structure of the dimer (75). ... 

Polyelectrolytes are polymers having a multiplicity of ionizable groups. In solution, they dissociate into polyions (or macroions) and small ions of the opposite charge, known as counterions. The polyelectrolytes of interest in this book are those where the polyion is an anion and the counterions are cations. Some typical anionic polyelectrolytes are depicted in Figure 4.1. Of principal interest are the homopolymers of acrylic acid and its copolymers with e.g. itaconic and maleic adds. These are used in the zinc polycarboxylate cement of Smith (1968) and the glass-ionomer cement of Wilson Kent (1971). More recently, Wilson Ellis (1989) and Ellis Wilson (1990) have described cements based on polyphosphonic adds. 

Ellis, J. Wilson, A. D. (1990). Polyphosphonate cements a new class of dental materials. Jourrml of Materials Science Letters, 9, 1058-60. 

Ellis and Wilson studied cements formed from concentrated solutions of poly(vinylphosphonic acid) (PVPA) and oxides and silicate glasses, which they termed metal oxide and glass polyphosphonate cements (Wilson ... 

Figure 8.3 Possible structures of metal-polyphosphonate complexes.

Miscellaneous aqueous cements 8.4.2 Glass polyphosphonate cements... 

Figure 8.4 The effect of Si/Al ratio in the glass on the setting time of glass polyphosphonate and glass polyalkenoate cements (Ellis, 1989).

Ellis, J., Anstice, M. Wilson, A. D. (1991). The glass polyphosphonate cement a novel glass-ionomer cement based on poly(vinylphosphonic acid). Clinical Materials, 7, 341-6. 

Many compositions involve environmentally dangerous products, such as chromates, fatty amines of high molecular weights, imidazolines, etc. The use of some of the alternatives, for instance, polyphosphate or polyphosphonate, is limited because they precipitate in the presence of the salts of alkaline earth metals or because of their high costs. 

Aliphatic iodine derivatives, 14 376 Aliphatic ketones, 14 563, 571, 581-585 reactions of, 16 331-332 Aliphatic monothiopolyesters, 23 739 Aliphatic nitration, 12 187 Aliphatic peroxyacids, 13 464 Aliphatic peroxycarboxylic acids, 18 463 Aliphatic phosphines, 19 60 Aliphatic polyamides (PA), 10 207-210 19 713, 739. See also Aromatic polyamides PA entries producers of, 10 210 properties of, 10 208, 209t Aliphatic polycarbonates, 24 703 preparation of, 19 798 Aliphatic polyketones (PK), 10 197 costs of, 10 222 properties of, 10 198t Aliphatic poly(monosulfide)s, 23 702-704 Aliphatic polyphosphonate dyes, 9 480 Aliphatic poly(polysulfide)s, 23 711 Aliphatic polysulfides, 23 734 Aliphatic polysulfoxides, 23 733 miscibility of, 23 735 Aliphatic polyurea preparation, carbonyl sulfide in, 23 625... 

Low molecular compounds Glucose, Sucrose, ATP, CH3CH2S03Na, Ct-Amino Acid, Polyphosphonic Acid, etc. 

Aromatic polyphosphonates have been found to be especially effective flame retardant additives for polyester compositions (j), 1, 8), especially for polyethylene terephthalate. 

In view of the utility of the aromatic polyesters and the demonstrated effectiveness of the aromatic polyphosphonates as flame retardants, the combination of these two polymers was chosen for this study. In addition, this system provided a composition in which both copolymers and polymer blends could be prepared with identical chemical compositions. The polyesters were prepared from resorcinol with an 80/20 m/m ratio of iso-phthaloyl and terephaloyl chlorides while the polyphosphonates were resorcinol phenylphosphonate polymers. Copolymerized phosphorus was incorporated by replacement of a portion of the acid chloride mixture with phenylphosphonic dichloride. 

Two series of aromatic polyester compositions, containing varying levels of phosphorus, were prepared by different methods (a) blending with an aromatic polyphosphonate and (b) copolymerization by incorporation of a phosphonate unit into the polyester backbone. 

Only a few systematic studies have been carried out on the mechanism of interaction of organic surfactants and macromolecules. Mishra et al. (12) studied the effect of sulfonates (dodecyl), carboxylic acids (oleic and tridecanoic), and amines (dodecyl and dodecyltrimethyl) on the electrophoretic mobility of hydroxyapatite. Vogel et al. (13) studied the release of phosphate and calcium ions during the adsorption of benzene polycarboxylic acids onto apatite. Jurlaanse et al.(14) also observed a similar release of calcium and phosphate ions during the adsorption of polypeptides on dental enamel. Adsorption of polyphosphonate on hydroxyapatite and the associated release of phosphate ions was investigated by Rawls et al. (15). They found that phosphate ions were released into solution in amounts exceeding the quantity of phosphonate adsorbed. 

F]-fluoride has a long history as a tracer for bone imaging. In 1962, this tracer was first introduced by Blau et al. [188]. [ F]-fluoride-PET imaging combines the superior pharmacokinetic properties of F-fluoride (compared with those of [99mTc]-polyphosphonates) and the improved spatial resolution and lesion... 

Another rule of thumb concerns the oxidation tendency of polymers. Carbonates and phosphates with the C02 and 0P03 moieties are already largely oxidized. Thus portions of polymers that contain the carbonate and phosphate molecules do not contribute to combustion. In fact, polyphosphate and polyphosphonate esters... 

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