N-Chloranil and N-Xylene Containing Polycations. Preparation and Solvation Characteristics

Abstract

ABSTRACT:Partial molar volume studies on four new types of cationic polyelectrolytes (mo! wt 1167 to 6432), where quaternized centres in oligomeric chain are essentially N-chloranil or N-xylylene ammonium/imminium moieties interspersed with ethylene, phenothiazin-5-ium and bipyridyl (viologen) links, have been undertaken in two dipolar aprotic solvents (dimethylformamide and dimethyl sulfoxide) over small temperature range (25 ± 5°C). A cumulative effect of competing electrostrictional and solvophobic interactions with the dipolar nonaqueous media was examined to explore the conformational alternations of these polymers at varying temperatures and concentrations.

Electrolytic Conductivity of the N-Chloranil- and N-Xylylene-Based Polyelectrolytes in Dimethylformamide and Dimethyl Sulfoxide

“…The System A possesses lower mobility in DMF as compared to B, in spite of its smaller size (n ) 3) (Table 3). This behavior could be explained on the basis of the structural background of the system, where quaternized nitrogen centers exert Coulombic interactions from both sides with carbonyl groups of chloranil moieties and immobilize themselves to curtail intercationic repulsions amidst massive solvation by DMF as reported earlier (Prasad et al, 1995). The high charge density of A in DMF and higher counterion condensation attenuate the movement of poly- Journal of Chemical and Engineering Data, Vol.…”

“…System B shows the highest mobility in DMF despite being made up of a long chain (n ) 8) (Table 3). This is attributed to the cumulative effects of two factors: (i) the lower charge density per unit cation reduces the magnitude of counterion condensation and thereby augments the mobility of the polyionic chain and (ii) the structural conformation allows a typical curling of the relatively large polycationic chain along the gN + -chloranil polar linkages, giving rise to an approximation of a "pearl necklace" model which offers permeability toward the solvent transport as suggested elsewhere (Singh et al, 1995).…”

“…Solvents DMF and DMSO (99% pure, Sarabhai-Merck, stated purity 99 mol % (CO 2 , <0.02 mol %; H 2 O, <0.03 mol %), conductivities 1.6 × 10 -8 S cm -1 (25 °C) (DMF) and 1.1 × 10 -8 S cm -1 (25 °C) (DMSO)) were purified and stored as described elsewhere (Prasad et al, 1995). All other chemicals either were high-purity materials or were purified before use.…”

“…Materials which fulfill the desired structural distinctions as stated above are A, poly[N-chloranil-N,N,N′,N′-tetramethylethylenediamine dichloride]; B, poly-[N-chloranil-methylene blue dichloride]; C, poly[N-xylylene-methylene blue dibromide]; and D, poly[N-chloranilviologen dichloride]. Details of the syntheses and characterizations of these polycations (structures in Figure 1) have been reported elsewhere (Prasad et al, 1995).…”

“…In the continuation of our earlier work concerning polyelectrolyte solvation through density (Prasad et al, 1995) and viscosity studies (Singh et al, 1995), the present paper describes conductance behavior of a few typical nitrogen-based polyelectrolytes in dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) having dielectric constants 36 and 45 at 25 °C, respectively. The systems studied have structural distinctions with the introduction of N-chloranil or N-xylylene free ammonium charge centers in their molecular backbone, where two proximate mN + -charge centers are either directly joined by the aliphatic chain or interceded with the polyaromatic charged heteroatombased system.…”