Poly-4-vinylbiphenyl

Two batches of PVN, prepared by emulsion polymerization, had molecular weights of 510,000 and 720,000 and were used for the blends and grafts, respectively. Both polystyrene (PS, Mw = 150,000) and poly-4-vinylbiphenyl (PVB, Mw = 450,000) were prepared by anionic polymerization. A low molecular weight (Polyglycol E4000, Dow Chemical Co.) and a high molecular weight PEO (WSR-35, Union Carbide Chemicals Co.) were used as received. 

Figure 4 shows the modulus curves for two blends of PEO E4000 (75 and 50%) with poly-4-vinylbiphenyl and one blend of 50% PEO E4000 with polystyrene. None of these blends exhibited a well, and at high temperatures the samples became friable and broke. 

Primary processes induced by ionizing radiation in the solution are excitation and ionization of the solvent molecules. Subsequent electron attachment to solute polymers leads to the formation of polymer anions. So far the radical anions of poly(methyl methacrylate) (PMMA) [46, 47], substituted PMMA [46, 47], poly(4-vinylbiphenyl) (PVB) [47-50], poly(l-vinylpyrene) (PVP) [50], organopolysilane [51] and substituted polyacetylene [52] have been studied. 

Fig. 9. Transient absorption spectra observed at ambient temperature on pulse radiolysis of MTHF solution containing 5 base-m mol dm " 3 poly(4-vinylbiphenyl-co-l-vinylpyrene). The content of pyrenyl group is 0.15% against the total number of the side groups. (O) pulse end ( ) 0.2 ps after a pulse (T1) 1.4 ps after a pulse [60]...

The absence of low energy excimer in solid solutions of PVCA and other aromatic polymers can easily be explained by the need of thermal activation to form a sandwich-pair (excimer-forming site) of two neighboring bulky aromatic groups. This has been shown by Frank for P2VN and Poly(4-vinylbiphenyl) (21,39). 

Frank CW (1974) Excimer formation in vinyl-polymers. 3. Fluid and rigid solutions of poly (4-vinylbiphenyl). J Chem Phys 61(5) 2015-2022. doi 10.1063/1.1682204... 

Table 1. Partial specific volume of poly(4-vinylbiphenyl).

Dissociation/Assodation Equilibria.—Further spectroscopic evidence has been forthcoming concerning the ion-pair equilibria of propagating species, in this instance poly(vinylbiphenyl) carboanions. As with caibocation systems the conductance technique also has been widely employed and continues to be so. ... 

High Refractive Index. Poly-vinylbiphenyl derivatives, Polym. Prepr. Jpn. 36 1163 (1987)... 

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