Liquid crystalline supramolecular crosslinked polymer complexes of ditopic rylenebisimides and P4VP

Abstract

Perylenebisimide and naphthalenebisimide (PBI-PDP and NBI-PDP) end functionalized with pentadecyl phenol is designed as ditopic hydrogen bonding acceptors to form supramolecular crosslinked network with poly(4-vinyl pyridine) (P4VP). The pristine PBI-PDP has been grown as single crystals from DCM-MeOH (dichloromethane-methanol) mixture at room temperature, which revealed a P21 space group. Noticeably, the pentadecyl alkyl chain shields the aromatic perylene core on both sides resulting in the absence of p-p interaction in single-crystal assembly. The naphthalenebisimide derivative exhibits thermotropic liquid crystalline behavior, while both the molecules exhibits lyotropic liquid crystalline phases in tetrahydrofuran (THF), which were characterized using a combination of differential scanning calorimeter, X-ray diffraction, and polarized light microscopy. The hydrogen-bonded complex of both the rylenebisimides with P4VP preserves the mesomorphic properties in THF. The electron transport mobility measured by space charge limited current measurements reveals a two orders of magnitude increase in the charge transport in the P4VP complex compared to that of the pristine molecule. The average electron mobility obtained is l e,avg : 10 23 cm 2 /Vs for P4VP-PBI compared to l e,avg : 10 25 cm 2 /Vs for pristine PBI derivative. V C 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 951-959

Self-Assembly of Bispentadecylphenol Substituted Perylenediimide with PS-b-P4VP for Structure–Property Insight into the Core of Core–Shell Micelles

“…In the case of complexes of PS- b -P4VP­(PDP) explored extensively in literature, the T g of the P4VP block is known to reduce due to the complex formation, but even the T g of the PS block is reduced due to the increased miscibility of the small molecule PDP (pentadecyl phenol) in styrene at higher temperature . PBI–PDP does not melt even until 400 °C and also does not exhibit any transition in the temperature range explored here . However, its presence near P4VP affects the glass transition temperature of the block copolymers.…”

“…The compositions of the three block copolymers as calculated from NMR were PS 20800 - b -P4VP 5200 , PS 20800 - b -P4VP 9350 , and PS 20800 - b -P4VP 15700 with volume fractions of P4VP ( f 4VP ) for each of the three blocks determined to be 0.20, 0.31, and 0.43, which are referred to as P-1, P-2, and P-3 respectively. The synthesis of the ditopic H-bondable perylenediimide (PBI–PDP) is detailed in our earlier reports . The complexes between the block copolymers and the PBI derivative were prepared by mixing the two components dissolved separately in dry DMF, heating at 60 °C for 24 h, followed by evaporating off the solvent in a Petri dish (details of procedure are given in Section S2).…”

“…The synthesis of the ditopic Hbondable perylenediimide (PBI−PDP) is detailed in our earlier reports. 36 The complexes between the block copolymers and the PBI derivative were prepared by mixing the two components dissolved separately in dry DMF, heating at 60 °C for 24 h, followed by evaporating off the solvent in a Petri dish (details of procedure are given in Section S2). The schematic representation of the supramolecular polymer complex formed between the block copolymer and the small molecule PBI− PDP via monotopic/ditopic H-bonding is given in Scheme 1.…”

“…41 PBI−PDP does not melt even until 400 °C and also does not exhibit any transition in the temperature range explored here. 36 However, its presence near P4VP affects the glass transition temperature of the block copolymers. The effect of complex formation of PBI−PDP with the P4VP block is more clearly observed in C-3, where the T g of the P4VP block almost disappeared.…”

“…We demonstrated that this comb-like self-assembly helped in improving the electron transport ability of the n-type perylenediimide molecule by several fold. 35,36 The aim of the current study is to make use of the ditopic PBI−PDP as a molecular probe to explore the self-assembled structures of PS-b-P4VP in solution using NMR spectroscopy. There is still a lot of gray area in our understanding of the dynamics of block copolymer micelles in block selective solvents.…”