Poly charge-transfer complexes

Charge-transfer complexes Dioxane, pyridine, polyvinyl, pyrrolid one, poly-2-vinvyl pyridine, polyethyleneoxide [4]... 

Interaction of PCSs with electron acceptors and donors results in molecular complexes with partial or complete charge transfer. In particular, detailed investigations involved charge transfer complexes (CTC) of poly (schiff base), polyazines, products of thermal transformations of PAN and a number of other PCSs129, 238, 241 243, 267. ... 

WD Gill, Drift mobilities in amorphous charge-transfer complexes of trinitrofluorenone and poly-n-vinylcarbazole, J. Appl. Phys., 43 5033-5040, 1972. 

When two polymeric systems are mixed together in a solvent and are spin-coated onto a substrate, phase separation sometimes occurs, as described for the application of poly (2-methyl-1-pentene sulfone) as a dissolution inhibitor for a Novolak resin (4). There are two ways to improve the compatibility of polymer mixtures in addition to using a proper solvent modification of one or both components. The miscibility of poly(olefin sulfones) with Novolak resins is reported to be marginal. To improve miscibility, Fahrenholtz and Kwei prepared several alkyl-substituted phenol-formaldehyde Novolak resins (including 2-n-propylphenol, 2-r-butylphenol, 2-sec-butylphenol, and 2-phenylphenol). They discussed the compatibility in terms of increased specific interactions such as formation of hydrogen bonds between unlike polymers and decreased specific interactions by a bulky substituent, and also in terms of "polarity matches" (18). In these studies, 2-ethoxyethyl acetate was used as a solvent (4,18). Formation of charge transfer complexes between the Novolak resins and the poly (olefin sulfones) is also reported (6). 

Fig. 4. Contact charge transfer complexes of nitrobenzene with VCZ and poly VCZ measurements of optical density at 437 mp. at room temperature Optical length 1 cm VCZ, -o- Poly VCZ in nitrobenzene, [NB] + [VCZ] = 0.3 M in benzene...

The charge transfer complexes of linear polymers of polystyrene, poly(acenaphthalene) and poly(vi-nyl naphthalene) with tetracyano-ethylene and other electron acceptors have been studied (99). 

Fig. 8. Dependence of conductivity of polymeric charge transfer complexes on the excess neutral tetracyanoqumonodimethane. 0 poly(methyI-2-vinylpyridiniura TCNQ), 0 styrene/(I -n-butyl-2-vinylpyridinium TCNQ) [from Lupinski and Koppel (HHH, x poly(vinylpyridlmum TCNQ) [from Hatano, Nomori and Kambara [102)]...

Polymeric charge transfer complexes of poly(N-vinyl carbazole) and TCNQ have also been investigated 104). These contained relatively little TCNQ <3 mole %). Consequently little enhancement of conductivity was observed. 

Since semiconductor materials appear to be general candidates for third order effects, it is not surprising that photoconductive charge transfer complexes such as poly(vinyl carbazole)-trinitrofluorenone (PVK-TNF) would exhibit modest DFWM.(142) The observed nonlinearity at 602 nm, a wavelength absorbed by the CT complex, ranges from 0.2 - 2 x 10"11 esu, increasing as the molar fraction of TNF in the complex, PVK TNF, increased. Charge... 

In the first part of this chapter we review some basic concepts of photoconductivity which are followed by a renew of some experimental techniques and how these have been applied to characterize some of the well known polymeric systems such as poly(N-vinyl carbazole) (PVK) and the charge transfer complex of PVK and 2,4,7,trinitro-9-fluorenone (TNF). The second part of this chapter is a review of the extensive original and patent literature on a variety of photoconducting polymers. 

Recently, Tanikawa et all94) discussed the photoconductivity of poly[i-( i-N-carbazolyethyl)-L-glutamate] and its charge transfer complex with 2,4,7, -trinitro-9-fluorenone. The photocurrents in this polymer are about one order of magnitude smaller than those of PVK at all measured wavelengths. The complex with TNF has a peak photocurrent at 600 nm while the absorption spectrum of the polymer... 

Chloromethylated polystyrene and chloromethylated poly(a-methyIstyrene) are negative type resists having high sensitivity and high resolution. In the pulse radiolysis of solid films of this polymer, the absorption spectra of substituted benzyl-type polymer-radical and the charge transfer complex between phenyl rings and chlorine atoms were observed (Fig. 17) [59], The benzyl-type radical may be produced by the dissociative electron attachment to the benzyl part of chloromethylated polystyrene (CMS). 

The poly-TV-vinylcarbarzole trinitrofluorenone (PVK TNF) charge-transfer complex [21-23] was the first commercial organic photoreceptor used in electrophotography by IBM. The photoconductivity of this material is comparable to that of amorphous selenium, but its utilization in practical devices was limited, owing to its toxicity and long transit-time value, comparable, as for most single-layer photoreceptors, to the development process time. 

DiMarco et al. (1986) investigated photogeneration of charge-transfer complexes formed between poly[bis-(2-naphthoxy)phosphazene] and 2,4,7-... 

Bassler (1984) reexamined Pfister s (1977) data for TPA doped PC. Bassler suggested that the field and temperature dependencies of the mobility could be explained by arguments based on energetic disorder. Bassler extended the same argument to a series of arylalkane derivatives doped into a PC and PS (Pai et al., 1983), and charge-transfer complexes formed between 2,4,7-trinitro-9-fluorenone and poly(N-vinylcarbazole) (Gill, 1972,1976). 

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