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A butadiene-styrene copolymer of low styrene eontent (5% Wt.) has been characterizedby ~1H NMR to have only isolated styrene units on the chain. The fluorescence spectra of thesample in dilute solutions of a good solvent (dichlorethane) at 25--26℃ show monomerfluorescence only. Changes of the fluorescence spectra from a good solvent to poor solvents(dichloroethanemethanol mixture), and form dilute to concentrated solutions up to the solidfilm confirm that excimer formation exists between nonadjacent chromophores in the ehainand between interchain chromophores. Comparison of the spectra obtained from a diluteθ-solution and solid film gives us an estimation of the relative importance of the intrachainexcimer interaction and interchain excimer interaction in the solid sample studied. Theseresults may help us visualize the interpenetration and entanglement of polymer coils duringtransition from a dilute solution to a concentrated one and to a solid polymer.
1H NMR to have only only styrene units on the chain. The fluorescence spectra of the samples in dilute solutions of a good solvent (dichlorethane) at 25-- 26 ° C show monomerfluorescence only. Changes of the fluorescence spectra from a good solvent to poor solvents (dichloroethanemethanol mixture), and form dilute to concentrated solutions up to solidfilm confirm that excimer formation exists between nonadjacent chromophores in the ehain and between interchain chromophores. Comparison of the spectra obtained from a dilute θ-solution and solid film gives us an estimation of the relative importance of the intrachainexcimer interaction and interchain excimer interaction in the solid sample studied. These results may help us visualize the interpenetration and entanglement of polymer coils during transition from a dilute solution to a concentrated one and to a solid polymer.