Fluorinated poly structures

Synthesis and Structure-Property Relationships of Lo w-Dielectric-C onstant Fluorinated Poly acrylates ... 

Before fluorination, the dielectric constant ofpoly(bisbenzocyclobutene) was 2.8, and this value was reduced to 2.1 after plasma treatment. No data were reported in the paper on characterization of structure or properties, except for the dielectric constant of the modified poly(bisbenzocyclobutene). The authors did report that the thermal stability offluorinatedpoly(vinylidenefluoride) was inferior to the original poly(vinylidenefluoride) when treated in a similar way. One of the probable reasons for the low thermal stability is that the NF3 plasma degraded the polymer. According to their results, the thickness of fluorinated poly(bisbenzo-cyclobutene) was reduced by 30%. The same phenomenon was observed for other hydrocarbon polymers subjected to the NF3 plasma process. A remaining question is whether plasma treatment can modify more than a thin surface layer of the cured polymer Additionally, one of the side products generated was hydrogen fluoride, which is a serious drawback to this approach. 

Fig. 8 Chemical structures of fluorinated poly(aryl ether ketone)s...

Scheme 2.12 Structure of fluorinated poly(aryl ether ketone)s containing both hexafluoroisopropylidene and 1,4-naphthalene moieties. Taken from Ref. [62].

Scheme 2.14 Representative structure of the fluorinated poly(arylene ether sulfide). Taken from Ref. [71],...

Scheme 2.16 Structure of fluorinated poly(phthalazinone ether)s containing allyl-terminated cross-linteible...

Scheme 2.23 Structure of fluorinated poly(arylene ether ketone) with sulfone moiety containing 1,4 naphthalene...

Scheme 2.24 Structure of fluorinated poly(arylene ether sulfone) containing an ethynyl end group as thermal cross-linkable groups. Taken from Ref [88],...

Scheme 2.31 Structure of sulfonated fluorinated poly(aryl ether ketone) with cross-linking alkyne moiety. Taken from Ref. [145],...

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. 

Scheme 2.36 Structures of sulfonated fluorinated poly(arylene ether)s using different bisphenol units in the polymer main chain.

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... 

Densely sulfonated fluorinated poly(arylene ether ketone) copolymers (SPAEK-xx, where xx=15, 20, 25, 30, and 35) was prepared by Pang et al. [172] and evaluated for proton conductivity. The Tg of the copolymers was in the range 193-231 °C and the T s% was in the range 364—390 °C, with a decreasing trend with an increase in the DS. The structure of the tetra-sulfonated fluorinated poly(arylene ether ketone) copolymer is shown in Fig. 2.11(a). 

Figure 2.11 (a) Structure of tetra-sulfonated fluorinated poly(arylene ether ketone) copolymer (taken from Ref. [172]) (b) TEM image of SPAEK-35. Reproduced with permission from Ref [172],... 

Scheme 2.46 Structure of comb-shaped densely sulfonated fluorinated poly(arylene ether)s with four sulfonic...

Figure 5.29 Reaction scheme and chemical structures of poly(arylene ether benzoxazole)s [51]. Table 5.3 Physical Properties of Fluorinated Poly(Arylene Ether Benzoxazole)s [51]...

A. Ghosh, S. Banerjee, Structure-property co-relationship of fluorinated poly(imide-siloxane)s, Polym. Adv. Technol. 19 (11) (2008) 1486-1494. 

Amphiphilic block copolymers that are soluble in CO2 comprise a C02-philic block and a CO2-phobic one and are thus prone to form complex structures in solution such as micelle-like aggregates and polymersomes. As a result of their high solubility, fluorinated poly(acrylates) and polysiloxanes mainly constitute the C02-philic building blocks of choice to design C02-soluble amphiphilic copolymers. 

Fluorinated poly(methacrylates) or poly(acrylates), rich in trifluoromethyl groups, exhibit superior performance of chemical inertness, excellent weatherability, low refractive index, lower dielectric constant, and special surface properties [14,61]. Poly(2,2,2-trifluoroethyl methacrylate), poly(MATRIF), is an important class of such materials. It has been extensively used in high performance coatings [17], photoelectric communications, and microelectronics [62]. Poly(MATRIF) is easily produced by free radical polymerization using bulk, solution, and emulsion polymerization methods [63]. Structural characterization of NMR of poly(MATRIF) prepared by radical and anionic polymerization has been studied. Syndiotactic structure was obtained by radical initiator in contrast to an isotactic structure achieved by anionic polymerization [64]. 

Scheme 7.4 Chemical structure of fluorinated poly(arylene ether) sDF-F...

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. 

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