In this study, metallo‐supramolecular polyesters with multiple coordination bonds along the chains are prepared, to demonstrate a simple strategy to control both the thermal property and crystallizability. Firstly, polyesters with multiple pyridine‐ligands are synthesized through melt polycondensation and subsequent Michael addition reaction. By adding a metal salt (ZnCl2), the fraction of metal‐coordinated pyridine‐ligands is systematically increased with increasing the Zn2+/pyridine‐ligands mole ratio according to Fourier transform infrared spectroscopy (FT‐IR) measurements, which is found to play a role in tuning the glass transition temperature. The metal‐ligand coordination simultaneously causes the disappearance of crystallization/melting peaks in differential scanning calorimetry (DSC) thermograms, and scattering measurements also indicate the disappearance of crystalline domains. A transparent film is thus obtained after blending small amounts of ZnCl2 (≪10 wt%), although the neat crystalline sample is highly opaque. This non‐crystallization phenomenon is induced by inhibition of the chain arrangement due to the existence of metal salts dispersed via coordination with pyridine‐ligands. By changing the fraction of pyridine‐ligands in the chain, it is found that the wider temperature range Tg tuning can be achieved for samples with higher ligand fractions.

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Coordinative polymers have gained great attention over the last two decades because of the potential versatile modification and functionalization of their physical properties. The pyridine isomer effects on metallo-supramolecular materials, where metal salts are blended with the polymers bearing pyridine coordinative ligands, have been frequently argued based only on steric effects. Here the pyridine isomer effects are investigated by both experimental and computational approaches. In the experimental approach, ZnCl 2 was blended with amorphous polyesters uniformly bearing either 4-vinylpyridine (4VP)-or 2vinylpyridine (2VP)-type ligands at the side groups. In addition, a polyester bearing both ligand types was also used to prepare blends with ZnCl 2 , which enabled deeper understanding of the pyridine isomer effects on the pyridine−metal coordination. Experimental characterizations by Fourier transform infrared spectroscropy, differential scanning calorimetry, and rheological measurements first revealed that the coordination of ZnCl 2 occurs more predominantly on 4VP ligands. Such pyridine isomer effects on the coordination are further investigated by density functional theory computation for complexes of ZnCl 2 with side chain models of 4VP or 2VP. On the basis of the obtained complex structures and stabilities, ZnCl 2 -complexation with two 4VP units was energetically more favored than for those with two 2VP units or 4VP/2VP mixtures. The coordination preference of the 4VP to ZnCl 2 was also confirmed by the stabilization of the interaction between the natural bond orbitals of the Zn-pyridyl N pair. Therefore, the theoretical approach can be applied to demonstrate the experimentally found unique isomeric effects of pyridine on metallo-supramolecular matrix, which will bring important insights into the practical application of coordinative polymers.

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Upon immersing into water, the chlorophyll a(chl a)/poly vinyl acetate) film cast from dioxane or dimethyl sulfoxide (DMSO) showed a transformation from chl a-dioxane aggregate (692 nm) to monomeric(668 nm) or from chl a-DMSO aggregate (695 nm) to (chl a·2H2O)n(746 nm), respectively. The platinum electrodes coated By the two types of transformed films showed the opposite direction of photo-induced potential shift.