Scholarlink

<p>In this study, the Schiff base 3-((2-phenylhydrazono)methyl)benzene-1,2-diol (3-PHMB) was synthesized through a condensation reaction between 2,3-dihydroxybenzaldehyde (2,3-DHBA) and phenylhydrazine (PH). The obtained Schiff base was subsequently subjected to oxidative polymerization in a 10% KOH (w/v) aqueous medium using hydrogen peroxide (35% H₂O₂), sodium hypochlorite (6–14% NaOCl), and oxygen (O₂) as oxidants, yielding the oligomers o-(3-PHMB)-P, o-(3-PHMB)-H, and o-(3-PHMB)-O. The structural, morphological, thermal, optical, and electrochemical characteristics of the synthesized compounds were comprehensively investigated using FT-IR, NMR, SEM, TG-DTA, UV-Vis, CV, and GPC techniques. UV-Vis and CV analyses revealed that the optical band gaps (<i>E</i><sub><i>g</i></sub>) were 2.33&#xa0;eV for 3-PHMB, 2.06&#xa0;eV for o-(3-PHMB)-P, 2.16&#xa0;eV for o-(3-PHMB)-H, and 2.02&#xa0;eV for o-(3-PHMB)-O, while the electrochemical band gaps (<i>E</i><sub><i>g</i></sub><i>′</i>) were calculated as 2.03&#xa0;eV, 1.65&#xa0;eV, 1.63&#xa0;eV, and 1.50&#xa0;eV, respectively. Thermal analysis showed that the char yields at 1000&#xa0;°C were 41.43% for o-(3-PHMB)-P, 38.72% for o-(3-PHMB)-H, and 44.35% for o-(3-PHMB)-O. Dielectric measurements indicated that o-(3-PHMB)-O exhibited higher polarization capacity and energy storage ability compared to the other oligomers. Moreover, the electrical conductivity values increased steadily with frequency; at 100&#xa0;kHz, the conductivity was recorded as 1.74 × 10⁻⁵ S cm⁻¹ for o-(3-PHMB)-O and 1.64 × 10⁻⁵ S cm⁻¹ for o-(3-PHMB)-P. These findings demonstrate that the synthesized Schiff base oligomers are promising candidates for dielectric and optoelectronic applications due to their high thermal stability, controlled molecular weight distribution, and semiconducting properties.</p> Graphical Abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Oxidative polycondensation of phenylhydrazine-based Schiff base: structural, thermal, optical and dielectric investigations

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年4月24日

查看全文
  • İsmet Kaya,
  • Erdal Bayır,
  • Adnan Solmaz

摘要

In this study, the Schiff base 3-((2-phenylhydrazono)methyl)benzene-1,2-diol (3-PHMB) was synthesized through a condensation reaction between 2,3-dihydroxybenzaldehyde (2,3-DHBA) and phenylhydrazine (PH). The obtained Schiff base was subsequently subjected to oxidative polymerization in a 10% KOH (w/v) aqueous medium using hydrogen peroxide (35% H₂O₂), sodium hypochlorite (6–14% NaOCl), and oxygen (O₂) as oxidants, yielding the oligomers o-(3-PHMB)-P, o-(3-PHMB)-H, and o-(3-PHMB)-O. The structural, morphological, thermal, optical, and electrochemical characteristics of the synthesized compounds were comprehensively investigated using FT-IR, NMR, SEM, TG-DTA, UV-Vis, CV, and GPC techniques. UV-Vis and CV analyses revealed that the optical band gaps (Eg) were 2.33 eV for 3-PHMB, 2.06 eV for o-(3-PHMB)-P, 2.16 eV for o-(3-PHMB)-H, and 2.02 eV for o-(3-PHMB)-O, while the electrochemical band gaps (Eg′) were calculated as 2.03 eV, 1.65 eV, 1.63 eV, and 1.50 eV, respectively. Thermal analysis showed that the char yields at 1000 °C were 41.43% for o-(3-PHMB)-P, 38.72% for o-(3-PHMB)-H, and 44.35% for o-(3-PHMB)-O. Dielectric measurements indicated that o-(3-PHMB)-O exhibited higher polarization capacity and energy storage ability compared to the other oligomers. Moreover, the electrical conductivity values increased steadily with frequency; at 100 kHz, the conductivity was recorded as 1.74 × 10⁻⁵ S cm⁻¹ for o-(3-PHMB)-O and 1.64 × 10⁻⁵ S cm⁻¹ for o-(3-PHMB)-P. These findings demonstrate that the synthesized Schiff base oligomers are promising candidates for dielectric and optoelectronic applications due to their high thermal stability, controlled molecular weight distribution, and semiconducting properties.

Graphical Abstract