Fluorinated poly monomer

High-molecular-weight fluorine-containing aromatic poly(benzoxazole)s have not been obtained either by the direct solution polycondensation in PPA at 200°C or by the low-temperature solution polycondensation in DMAc at 0 to 5°C from 2,2-bis(3-amino-4-hydroxyphenyl)-l,l,l,3,3,3-hexafluoropropane and aromatic diacid derivatives because the fluorine-containing monomer has low nucleophilicity owing to the presence of the electron-withdrawing hexafluoroiso-propylidene unit. 

Using a fluorinated benzocyclobutene-based monomer (Figure 18.4) should provide at least one advantage over the already promising properties of fluorinated poly(j9-xylylene). All the desirable properties such as low dielectric constant and low affinity for water should remain but the thermal stability should be enhanced because of the cross-linking that would accompany the generation of these films. The synthesis and polymerization paths for poly(octafluorobisbenzocyclobutene) are depicted in Scheme 5. 

A series of water-dispersible, surface-active poly(fluorinated oxetane)s was prept sd by ring-opening polymerization of fluorinated oxetane monomers using Lewis acid catalysis <02L5993>. 

Pareek K, Ghosh A, Sen SK, Banerjee S. Synthesis, characterization and properties of new fluorinated poly(imide siloxane) copolymers from 4,4 -(hexafluoro-isopropylid-ene)diphthalic anhydride. Des Monomers Polym 2010 13(3) 221-36. 

Zhang et al. [151] used Ni(0)-catalyzed coupling copolymerization to synthesize a series of sulfonated fluorinated poly(p-phenylene-co-aryl ether ketone)s (SPP-co-PAEKs). Copolymerization with the sulfonated monomer 2,5-dichloro-3 -sulfobenzophenone (DCSB) and 2,2 - w[4-(4-chlorobenzoyl)]phenoxyl perfluoropropane (BCPPF) was carried out by varying the molar ratio of DCSBrBCPPF. The structure of SPP-co-PAEKs is shown in Scheme 2.35. 

Furthermore, Banerjee and group prepared sulfonated fluorinated poly(arylene ether sulfone) (IBQSH-XX) copolymers (where XX=20, 30, 40, 50, and 60 and DS=0.16, 0.26, 0.39, 0.47, 0.56, respectively) based on imidoaryl biphenol, namely, 3,8-few(4-hydroxyphenyl)-A -phenyl-l,2-naph-thaUmide (IB), by direct copolymerization with SDCDPS as the sulfonated monomer and QBF as the fluorinated monomer [160]. Sulfonated copolymers were obtained with M values in the range 41,200-60,200g/mol with D values in the range 0.96-1.89 the trend increased with an increase in the DS (0.16-0.56 as per H-NMR spectra). Scheme 2.36 shows a representative structure of sulfonated fluorinated poly(arylene ether sulfone) containing IB... 

A. Ghosh, S. Chatterjee, S. Banerjee, H. Komber, B. Voit, Linear and hyperbranched poly(arylene ether)s from a new semi fluorinated ah monomer, J. Macromol. Sci., Part A Pure Appl. Chem. 48 (7) (2011) 509-517. 

A new aromatic diamine monomer with four pendant -CF3 groups was successfully synthesized by a three-step reaction using w(4-fluorophenyl)sulfone and A-bromosuccinimide as starting materials. Then, a series of fluorinated poly(ether sulfone imide)s was conveniently prepared from the diamine and three aromatic dianhydrides (BPDA, BTDA, and ODPA) via one-step solution polycondensation. 

Hilborn et al. demonstrated the synthesis of PBOs (Figure 5.29) by polymerization of bis(fluorophenyl benzoxazoles) with bisphenols. This polymerization was based on the activation of the fluoro group toward nucleophilic aromatic substitution by the oxazole component of the benzoxazole heterocyclic [51]. The TgS of the poly(arylene ether benzoxazoles) ranged from 213 to 303 °C, depending on the bisphenol and activated dihalide used in the synthesis. Generally, the TgS increased with the bulkiness of the bisphenol used. The polymers containing the >C(CF3)2 unit in both the benzoxazole and the bisphenol moiety in the monomers showed higher solubility (NMP) compared to the other PBOs. The physical properties of fluorinated poly(arylene ether benzoxazole) s are presented in Table 5.3. 

It is obvious that this reaction easily lends itself to higher functionality aromatic species and, therefore, to the creation of aromatic poly(ether ketone) and poly(thioether ketone) networks. Amorphous poly(ether ketones) were recently prepared [483-485] by the complex reaction of the abstraction of fluorine atoms from aromatic kernels and their partial substitution by oxygen using the reaction of potassium carbonate with fluorine-containing monomers ... 

A monomer for a fluorinated poly(arylene ether-phosphine oxide) polymer was prepared by the P-C coupling of a dioxoalkojg aiyl iodide with bis(3,4,5-trifluorophenyl)phosphine oxide under the classical conditions of the Hirao reaction (Scheme 36). ... 

Vinyl Fluoride. Vinyl fluoride [75-02-5] C2H2F, the monomer for poly(vinyl fluoride), is manufactured by addition of hydrogen fluoride to acetylene (see Fluorine COMPOUNDS, ORGANIC, POLY(viNYL FLUORIDE)). 

The fraction of head-to-head linkages in the poly(fluoro-olefms) increases in the series PVF2 < PVF PVF3 (Tabic 4.2). This can be rationalized in terms of the propensity of electrophilic radicals to add preferentially to the more electron rich end of monomers (i.e, that with the lowest number of fluorines). This trend is also seen in the reactions of trifluoromethyl radicals wilh the fluoro-olefins (see 2.3). 

A preferable system is poly(p-fluorostyrene) doped into poly(styrene). Since rotations about the 1,4 phenyl axis do not alter the position of the fluorine, the F spin may be regarded as being at the end of a long "bond" to the backbone carbon. In standard RIS theory, this polymer would be treated with dyad statistical weights to automatically take into account conformations of the vinyl monomer unit which are excluded on steric grounds. We have found it more convenient to retain the monad statistical weight structure employed for the poly(methylene) calculations. The calculations reproduce the experimental unperturbed dimensions quite well when a reasonable set of hard sphere exclusion distances is employed. 

Stereoselective ROMP has been reported with monomer (213). Initiator (211) affords highly stereoregular polymer with >98% trans C=C bonds in the polymer backbone.534 However, when (210) is used, >98% cis-poly-(213) is obtained.535 A similar situation occurs for the diester monomer (214). Furthermore, a rapidly equilibrating mixture of (210) and (211) can be used to allow intermediate cis/trans contents to be manipulated by the stoichiometry of the initiator mixture. 13C NMR536 and dielectric analyses537 suggested that trans-poly-(213) is highly syndio-tactic (92% r dyad content). The ROMP of other fluorinated olefins has been recently reviewed.538... 

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