Enhancement of the Physical Properties of Poly((2-terthiophenyl)norbornene) through Cross-Linking Pendant Terthiophenes

Abstract

The synthesis of norbornene polymers containing 2-terthiophenyl side chains, poly((2-terthiophenyl)norbornene), by ring-opening metathesis polymerization (ROMP) and the cross-linking of pendant terthiophene units to form conductive polymers is reported. Physical characteristics including conductivity, thermal stability, electrochromic activity, fluorescence, and surface topography are evaluated for the resulting cross-linked ROMP polymers and compared to those of poly(terthiophene). The in-situ conductivity of cross-linked ROMP polymer films doped with PF6 - was approximately half that of poly(terthiophene) films. However, thermal stability was substantially higher for powders formed from chemically cross-linked ROMP polymers, which retained 60% of their total mass at 800 °C compared to a total decomposition of non-cross-linked ROMP polymers at 500 °C. Electrochemically deposited films of cross-linked ROMP polymers proved to have considerably higher thermal stability and smoother, more uniform surfaces than films of poly(terthiophene). The root-mean-square value of electrochemically cross-linked ROMP polymer films, derived from atomic force microscopy images (AFM), was approximately 6 nm while that of poly(terthiophene) films prepared in the same manner was 118 nm. These cross-linked films display a reversible electrochromic color change when oxidatively doped.

Synthesis, characterization, and thermal properties of ring‐opening metathesis polynorbornenes and their hydrogenated derivatives bearing various ester and cyano groups

“…[37][38][39][40][41][42][43][44][45] Among polycycloolefins, polynorbornenes synthesized by ROMP [46][47][48][49][50][51] are applicable for organic synthesis, 52,53 recognition arrays rele-vant to cell signaling, 54 DNA diagnostics, 55 drug delivery, 56 antibacterial materials, 57 and photoand electrochromic devices and transistors. [58][59][60][61] Based on these research backgrounds, increasing interest in ROMP of norbornene derivatives containing functional groups has developed over the recent years, aiming to obtain polymer structures directed towards attractive properties. 62,63 Functionalized polynorbornenes would be more optically homogeneous and have high glass-transition temperatures (T g s) because the bulky and unsymmetrical polycyclic structure in the main chain should prevent crystallization.…”

Synthesis, Characterization, and Properties of Homopolymers Functionalized with Oligothiophene Derivatives in the Side Chain

“…0.32 V, which can be attributed to the reduction of cross-linked polymer resulting from electrochemical polymerization of the sexithiophene side chain present in 12. 14,15 Upon a second scan cycle, a new oxidation process occurred at ∼0.55 V (E pa ), which can be attributed to the oxidation of a newly in-situ formed cross-linked conjugated polythiophene backbone within polymer 12. Scanning in the reverse direction led to a cathodic process with a response identical to that observed in the initial scan.…”

Facile potentiostatic preparation of functionalized polyterthiophene-anchored graphene oxide as a metal-free electrocatalyst for the oxygen reduction reaction

“…This is mainly because the APT monomer consists of a thermally stable terthiophene backbone, resulting in excellent thermal properties. 36 For a comparative study, the thermal stabilities of the TCA-GO and TBA-GO complexes were also investigated. Although they exhibited better thermal properties than pure GO, they showed severe weight loss; a 45% weight loss was observed for TBA-GO and a 57% weight loss for TCA-GO.…”