Journal ArticleDOI
Spectroscopic and light scattering studies of the conformational (rod‐to‐coil) transition of poly(diacetylene) in solution
K. C. Lim,A. J. Heeger +1 more
TLDR
A rod-to-coil conformational transition has been demonstrated for polydiacetylene, 4-butoxy-carbonyl-methylurethane (4BCMU) in solution as mentioned in this paper.Abstract:
A rod‐to‐coil conformational transition has been demonstrated for polydiacetylene, 4‐butoxy‐carbonyl‐methylurethane (4BCMU) in solution. The transition can be induced by changing either the temperature or the quality of the solvent. The light scattering and spectroscopic data as a function of polymer concentration have shown that the transition is a single chain (intramolecular) phenomenon. However, because of the large end‐to‐end length (L≂1.2 μm) of the fully extended polymer, the dilute limit is not reached until concentrations below 10−5 g/cm3. At higher concentrations evidence of cluster growth and aggregation are observed prior to gelation which occurs above a critical concentration c0≂5×10−4 g/cm3. This cluster growth occurs as a result of the rod‐like conformation of the individual molecules, but it is not the cause of the transition. The large increase in scattering intensity (at fixed polymer concentration) on going from coil to rod follows directly from the change in dielectric constant due to ...read more
Citations
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Thermochromic and solvatochromic effects in poly(3-hexylthiophene)
TL;DR: In this paper, the authors report thermochromic and solvatochromatic effects in the soluble conductive polymer poly(3-hexylthiophene) and discuss these effects with reference to the existence of a hitherto disregarded type of conformational defect, conformons.
Journal ArticleDOI
Room-Temperature Synthesis and Characterization of Nanocrystalline CdS, ZnS, and CdxZn1-xS
TL;DR: In this paper, a simple chemical reduction route at room temperature is described to synthesize nanocrystalline CdS, ZnS, and CdxZn1-xS.
Journal ArticleDOI
Synthesis, characterization and applications of thiophene-based functional polymers
TL;DR: A review on some recent developments in thiopene-based functional polymers concentrates on (i) the synthetic trends for low bandgap and regioregular materials which occupy a central place in the recent advances in polythiopene, (ii) the interesting physics and chemistry of special properties such as chromism and luminescence, (iii) the effect of C60 on the polymer and (iv) the formation and property of polythio-LB films.
Journal ArticleDOI
Relaxation dynamics of photoexcitations in polydiacetylenes and polythiophene
TL;DR: In this paper, the authors investigated the relaxation dynamics of photoexcitations in cast films of polydiacetylenes, poly[4,6-decadiyne-1,10-diol bis([(n-butoxycarbonyl)methyl]urethane)] (PDA-3BCMU) and poly[5,7-dodecadiyn- 1,12-diox bis([n- butoxycarbonyl)methyl)urethANE)] (pDA-4BCMU), and in electrochemically prepared
Journal ArticleDOI
Titration Behavior and Spectral Transitions of Water-Soluble Polythiophene Carboxylic Acids
Kim,Li Chen,Gong,Yoshihito Osada +3 more
TL;DR: Water-soluble poly(3-thiophene acetic acid) (P3TAA) and its copolymers with 3-n-methylthiopane or with 3n-octadecylthiophenes were synthesized in this paper.
References
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Journal ArticleDOI
A planar–nonplanar conformational transition in conjugated polymer solutions
TL;DR: In this paper, the color changes are due to a planar-nonplanar conformational transition of the polymer backbone, which is stabilized by intramolecular hydrogen bonding between urethane functionalities on adjacent substituent groups.
Journal ArticleDOI
Polyacetylene, (CH)x: The Prototype Conducting Polymer
and S Etemad,A J Heeger +1 more
Journal ArticleDOI
Rod-to-coil transition of a conjugated polymer in solution
TL;DR: In this paper, a rod-to-coil conformational transition for polydiacetylene, 4-butoxycarbonylmethylurethane, in solution is demonstrated.
Journal ArticleDOI
Raman photoselection and conjugation-length dispersion in conjugated polymer solutions
TL;DR: In this article, a model for the conjugation-length dispersion was presented and found to be in good agreement with absorption profiles, frequency shifts, and resonance Raman scattering intensities.