Controlling photo-oxidation processes of a polyfluorene derivative: The effect of additives and mechanism

Abstract

h i g h l i g h t sPhoto degradation control of a fluoreneevinyleneephenylene based polymer was achieved. A radical scavenger enhanced photo resistance and radical initiator decreased it. Color change rate with irradiation dose provided a basis for dosimeter construction. The control of the photo degradation of a fluoreneevinyleneephenylene based-polymer, poly(9,9-dihexylfluorenediylvinylene-alt-1,4-phenylenevinylene) (LaPPS16) was achieved by addition of a radical scavenger (RS) (enhancing photo resistance) or a radical initiator (RI) (reducing photo resistance). Photoluminescence, UVeVis absorption, 1 H NMR spectroscopies and gel permeation chromatography (GPC) revealed that the incorporating small amounts of RS or RI is an efficient way to control the rates of the photo-oxidation reactions, and thus to obtain the conjugated polymer with foreseeable degradation rates for applications in blue-light sensitive detectors for neonatal phototherapy.

X-rays sensing properties of MEH-PPV, Alq3 and additive components: A new organic dosimeter as a candidate for minimizing the risk of accidents of patients undergoing radiation oncology

“…MEH-PPV/Alq 3 was also dissolved in chloroform containing benzoyl peroxide (from Aldrich Sigma) and hindered phenolic stabilizers (Irganox 1010 @ , from Ciba Specialty Chemical Corporation), an accelerator and an inhibitor of radical formations, respectively. The additives were used to enhance the stability of MEH-PPV by a hindered phenol as well to reduce it by peroxides [16,17], and no significant differences in the line shape of ABS and PL curves of MEH-PPV/Alq 3 solutions were observed with the presence of these additives. These solutions will be described as MEH-PPV/Alq 3 :accelerator and MEH-PPV/Alq 3 :inhibitor.…”

“…Consequently, the slowdown of the photo degradation by the presence of the free radical scavenger indicates that free radicals act as an accelerator of the photo-oxidation process. However, despite this effort, there are still uncertainties associated with role of these compounds on the degradation process of PPV-type polymers, thus becoming a significant subject of study for future publications [17].…”

Assembly of transition metal ion on cellulose surface anchored with azo-Schiff base and its catalytic activity for H2O2 decomposition

“…(2015) [1][2][3][4][5][6][7][8][9] www.deswater.com doi: 10.1080/19443994.2015.1099474 complexes from water. This can result in the second water contamination.…”

“…In the last years, polymer-supported catalysts for wastewater treatment have received considerable interest among the academia and industries due to their unique structures and excellent properties [1][2][3]. The polymer-supported catalysts enhance their thermal stability, selectivity, recyclability, and easy separation from wastewater or reaction products [4].…”

Crystalization-enhanced Stability by Effectively Suppressing Pho-tooxidation Defect for Lasing Emission and Electroluminescent Device

“…23,24 In uorene-based OWBGS systems, defects are generally originated from the presence of ketone sites and aggregation behaviors, where the former has been demonstrated but is rather di cult to be overcome. 25,26 In order to stabilize the uorene-based semiconductors, various strategies have been explored, including rational molecular design, 27 aggregate modulation, 28 device packaging 29 and so on. For example, in terms of electronic structures, the highest occupied molecular orbital (HOMO) energy level should not be high to defend H 2 O/O 2 attacking.…”