Polyarylates synthesis

Polyarylate synthesis CRNl + SSE Devolatilization using 3 vents ... 

The relationships, similar to the Eq. (34) were adduced in paper [62] for each diphenol and the average values c, and c were determined for the calculations according to these data simplification. In this case for polyarylates synthesis the Eq. (34) assumes the following form [67] ... 

Mikitaev, A. K. Musaev, Yu. L Korshak, V. V. Kinetics and mechanics of high-tem-perature polycondensation reaction in solution at polyarylates synthesis. In collection Poly condensation processes and polymers. Ed. Mikitaev, A. Nal chik, KBSU, 1976,180-211. 

Diphenols are scarcely reactive towards aromatic diacids (2) and only low molecnlar weight polymers can be achieved through their direct reaction. To increase the reactivity and promote the polycondensation, at least one of the monomers has to be properly activated. Thus, two processes have been conceived for polyarylate synthesis interfacial polycondensation (preferred over the solution process) between diacyl chlorides and alkali metal diphenate, and the high temperature metal-catalyzed melt polycondensation between either diphenol acetates and aromatic diacids, or diphenols and diacid diphenyl esters. 

Solvent for Displacement Reactions. As the most polar of the common aprotic solvents, DMSO is a favored solvent for displacement reactions because of its high dielectric constant and because anions are less solvated in it (87). Rates for these reactions are sometimes a thousand times faster in DMSO than in alcohols. Suitable nucleophiles include acetyUde ion, alkoxide ion, hydroxide ion, azide ion, carbanions, carboxylate ions, cyanide ion, hahde ions, mercaptide ions, phenoxide ions, nitrite ions, and thiocyanate ions (31). Rates of displacement by amides or amines are also greater in DMSO than in alcohol or aqueous solutions. Dimethyl sulfoxide is used as the reaction solvent in the manufacture of high performance, polyaryl ether polymers by reaction of bis(4,4 -chlorophenyl) sulfone with the disodium salts of dihydroxyphenols, eg, bisphenol A or 4,4 -sulfonylbisphenol (88). These and related reactions are made more economical by efficient recycling of DMSO (89). Nucleophilic displacement of activated aromatic nitro groups with aryloxy anion in DMSO is a versatile and useful reaction for the synthesis of aromatic ethers and polyethers (90). 

Bisphenol-A benzoxazine reaction, under acidic conditions, 416-417 Bisphenol-A polyarylates, 77 synthesis of, 109-113 Bisphenol-A polysulfone, 327 nucleophilic synthesis of, 337 Bisphenolic monomer, 354 Biurets, 227... 

In their efforts to construct stimuli-responsive, supramolecular amphiphiles, Frechet et al. [126-129] reported the synthesis of a novel series of AB and ABA block copolymers via the Williamson ether synthesis (e.g., 47, Fig. 21). Polyethylene glycols (PEGs) of different lengths were used as the linear hydrophilic B block while polyaryl ether dendrons of different sizes were used as the hydro-phobic A block. These copolymers were characterized by optical microscopy,... 

Early and prescient work to develop correlations between biological observables and the physico-chemical properties of polymers were reported by Brocchini and Kohn [3, 32, 166]. Prior to the development of the models, the authors had been engaged in the combinatorial synthesis of a 112-member library of polyarylates, prepared through the condensation of diphenols with diacids (Fig. 12). 

Dendritic analogues of engineering plastics-A general one-step synthesis of dendritic polyaryl ethers [T. M. Miller, T. X. Neenan, E. W. Kwock, S. M. Stein, Macromol. Symp. 1994, 77, 35-49]. 

Coordination carbonylation polycondensation has been extended from the synthesis of polyamides [scheme (15)] and polyarylates [scheme (16)] to reactions using other nucleophilic monomers that, with dihaloarenes and carbon monoxide, yield poly(imide-amide)s, poly(acylhydrazide)s, and poly(benzoxa-zole)s [165,170,171],... 

Aryl-aryl cross-coupling reactions have been exploited extensively, particularly by Snieckus and coworkers, in the synthesis of polyaryls and other aromatic nuclei243. 

Stepwise double coupling of two different arylboronic acids with a dihaloarene afforded one-pot, two-step method for synthesizing unsymmetrical teraryls, quateraryls, and other higher order polyaryls.882 The first total synthesis of dragmacidin D involved a sequential double coupling of two different pinacol 3-indoleboronic esters (ArBpin Equation (207)).882... 

Synthesis. Five different polyaryl ethers were made from the condensation product, resulting from the reaction of phenol and levulinic acid, commonly referred to as diphenolic acid, and one or more of the following monomers bisphenol A, dichlorodiphenyl sulfone, 2,6-dichloro-benzonitrile, and 4,4 -difluorobenzophenone. The resulting polymers were subsequently methylated such that the common monomer becomes (1) ... 

The synthesis of teraryls, quateraryls, and further higher-order polyaryls, and the ever-increasing complexity in the more functionalized materials requires simple and practical methods for synthesizing building blocks (Scheme 33). The transmetalation between an aryllithium, -magnesium, or other metal (Al, Si,Zn)... 

Shen, L., Shi, M., Li, F.Y., et al. (2006) Polyaryl ether dendrimer with a 4-phenylacetyl-5-pyrazolone-based terbium(III) complex as core synthesis and photophysical properties. Inorganic Chemistry, 45, 6188-6197. 

In an extensive series of papers beginning in 1985, Hart and co-workers [32] developed and elaborated a one-pot reaction for the synthesis of polyaryl benzenes, using aryl Grignard... 

For phosphorescence, lanthanide metal ions can be used in a similar manner. Lanthanide ions have very interesting photophysical properties, but often exhibit weak absorption bands, and aggregate to form clusters, which limit their applications. Thus, a dendrimer that can provide a protective shell to isolate a cation and at the same time enhance the emission by transfer from the periphery to the lanthanide ion at the core could be of great interest. Self-assembled lanthanide-cored dendrimers have been prepared to prove such an assumption synthesis was carried out by mixing three equivalents of polyaryl ether dendrons bearing carboxylic acid entity at the focal point with Ln(III) cations [Er(III), Tb(III), and Eu(III)] (Fig. 5.4) [34]. The authors demonstrated that the enhancement of the lanthanide cation emission associated with the dendritic core shell was observed, and an antenna effect from the periphery to the core was shown to promote this process. 

Hydrazine derivatives also open the ring of pyrylium salts (18) to form open-chain products (19) which undergo recyclization. The applicability of this method of synthesis is strictly limited as only polyaryl pyrylium salts react smoothly. Of possible hydrazine derivatives, only alkyl or aryl hydrazines were used.33-41... 

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