The effects of polymer molecular weight on the performance of single-layer polymer light emitting diodes

Rewritable resistive memory effect in poly[N-(3-(9H-carbazol-9-yl)propyl)-methacrylamide] memristor

“…From these measurements, the energy position of the HOMO level of PCaPMA was determined as E HOMO = −5.23 eV, slightly higher than PVCa, where the value E HOMO = −5.34 eV was obtained, consistent with previous literature reports. 29,45,46…”

“…From these measurements, the energy position of the HOMO level of PCaPMA was determined as E HOMO = À5.23 eV, slightly higher than PVCa, where the value E HOMO = À5.34 eV was obtained, consistent with previous literature reports. 29,45,46 Both polymers displayed CV curves that were not fully reversible and exhibited only weak reduction peaks. The bandgap, E g , was therefore determined from the Tauc plot of the optical absorption spectra.…”

Reducing the Efficiency Roll-Off in Organic Light-Emitting Diodes at High Currents under External Magnetic Fields

“…As one can see, in addition to the main emission centered at 612 nm (corresponding to the 5 D 0 → 7 F 2 transition in Eu 3+ ) and the other less-intense emission peaks from Eu 3+ , a small and broad EL emission in the 470-550 nm spectral region is also observed, which is most likely due to the exciplexes formed at the interface between PBD in the EML and PVK HTL. 27 No exciplex emission in the PL spectrum of the SimCP2:PBD blend is observed. Further, the PL spectrum of the blend looks very similar to that of PBD because of the higher weight ratio of PBD in the SimCP2:PBD blend (30:70 wt.%).…”

Relating Structure to Properties in Non‐Conjugated Pendant Electroactive Polymers

“…However, in addition to effects of the spacer length on charge carrier mobilities potential superimposed effect of molecular weight have to be considered given that M n of the two carbon spacer polymer is higher by an order of magnitude compared to both the three and the five carbon spacer polymers especially in light of established molecular weight effects in other NCPEPs such as higher hole mobility in PCzETPMA with higher M n and M n -dependent PL emission of OLEDs containing PVK. [122,123] A more in depth study on spacer length effects for a family of similar poly(N-carbazolylalkyl acrylates) that excluded potentially superimposing molecular weight effects of the varied spacer length was conducted by Thompson et al in 2021. [121] Two poly(methyl acrylate) parent polymers were synthesized by anionic polymerization in toluene with a n-BuLi and a PhMgBr initiator respectively affording dyad tacticities of 74% and 87% with molecular weights of 33.4 and 13.5 kg mol −1 and Ð ≤ 2.0.…”

“…However, in addition to effects of the spacer length on charge carrier mobilities potential superimposed effect of molecular weight have to be considered given that M n of the two carbon spacer polymer is higher by an order of magnitude compared to both the three and the five carbon spacer polymers especially in light of established molecular weight effects in other NCPEPs such as higher hole mobility in PCzETPMA with higher M n and M n ‐dependent PL emission of OLEDs containing PVK. [ 122,123 ]…”