TY - JOUR
T1 - Thermally cross-linkable hyperbranched polymers containing triphenylamine moieties
T2 - Synthesis, curing and application in light-emitting diodes
AU - Yu, Juin Meng
AU - Chen, Yun
N1 - Funding Information:
The authors thank the National Science Council of Taiwan for financial aid through project NSC 98-2221-E-006-003 MY3.
PY - 2010/9
Y1 - 2010/9
N2 - This paper demonstrates synthesis of hyperbranched polymers (HTP and HTPOCH3), containing triphenylamine moieties in main chain and thermally cross-linkable periphery or terminal vinyl groups, and application as hole-transporting layer (HTL) in multilayer light-emitting diodes. Absorption and photoluminescence (PL) spectroscopy, cyclic voltammetry (CV) and differential scanning calorimetry (DSC) were employed to investigate their photophysical, electrochemical properties and thermal curing behaviors, respectively. The hyperbranched HTP and HTPOCH3 were readily cross-linked by heating scan, with the exothermic peaks being at 221 and 210 °C respectively. The glass-transition temperatures (Tg) of the hyperbranched polymers were higher than 140 °C after thermal cross-linking at 210 °C for 30 min. Multilayer light-emitting diodes (ITO/PEDOT:PSS/HTL/MEH-PPV/Ca/Al), using HTP and HTPOCH3 as HTL, were readily fabricated by successive spin-coating. The performance of MEH-PPV device (maximum luminance: 9310 cd/m2, luminance efficiency: 0.26 cd/A) was effectively enhanced by inserting the thermally cross-linked HTP or HTPOCH3 as HTL (HTP: 12610 cd/m2, 0.32 cd/A; HTPOCH3: 14060 cd/m2, 0.33 cd/A). This indicates that these thermally cross-linkable hyperbranched HTP and HTPOCH3 are very suitable for the fabrication of multilayer PLEDs using solution processes.
AB - This paper demonstrates synthesis of hyperbranched polymers (HTP and HTPOCH3), containing triphenylamine moieties in main chain and thermally cross-linkable periphery or terminal vinyl groups, and application as hole-transporting layer (HTL) in multilayer light-emitting diodes. Absorption and photoluminescence (PL) spectroscopy, cyclic voltammetry (CV) and differential scanning calorimetry (DSC) were employed to investigate their photophysical, electrochemical properties and thermal curing behaviors, respectively. The hyperbranched HTP and HTPOCH3 were readily cross-linked by heating scan, with the exothermic peaks being at 221 and 210 °C respectively. The glass-transition temperatures (Tg) of the hyperbranched polymers were higher than 140 °C after thermal cross-linking at 210 °C for 30 min. Multilayer light-emitting diodes (ITO/PEDOT:PSS/HTL/MEH-PPV/Ca/Al), using HTP and HTPOCH3 as HTL, were readily fabricated by successive spin-coating. The performance of MEH-PPV device (maximum luminance: 9310 cd/m2, luminance efficiency: 0.26 cd/A) was effectively enhanced by inserting the thermally cross-linked HTP or HTPOCH3 as HTL (HTP: 12610 cd/m2, 0.32 cd/A; HTPOCH3: 14060 cd/m2, 0.33 cd/A). This indicates that these thermally cross-linkable hyperbranched HTP and HTPOCH3 are very suitable for the fabrication of multilayer PLEDs using solution processes.
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U2 - 10.1016/j.polymer.2010.08.001
DO - 10.1016/j.polymer.2010.08.001
M3 - Article
AN - SCOPUS:77956610747
SN - 0032-3861
VL - 51
SP - 4484
EP - 4492
JO - Polymer
JF - Polymer
IS - 20
ER -