Chemically oxidative polymerization of aromatic diamines: The first use of aluminium-triflate as a co-catalyst

Polymer ◽  
2013 ◽  
Vol 54 (2) ◽  
pp. 505-512 ◽  
Author(s):  
Ismael Amer ◽  
Desmond Austin Young
Keyword(s):  
Oxidative Polymerization ◽  
Aromatic Diamines ◽  
Co Catalyst

scholarly journals Chemical Oxidative Condensation of Benzidine in Non-Aqueous Medium: Synthesis and Investigation of Oligomers and Polymer with Benzidine Diimine Units

Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 34
Author(s):  
Ranush Durgaryan ◽  
Narine Durgaryan
Keyword(s):  
Oxidative Polymerization ◽  
Matrix Decomposition ◽  
Oxidative Condensation ◽  
Aromatic Diamines ◽  
Acid Media ◽  
Molar Ratios ◽  
Potassium Peroxydisulfate ◽  
Type Change ◽  
First Time ◽  
Semiconductor Type

The oxidative condensation of benzidine has been carried out in acetic acid media using potassium peroxydisulfate as the oxidizing agent. Using different monomer–oxidant molar ratios, benzidine dimer, trimer, and polymer have been synthesized for the first time. It was established that the polybenzidine structure is composed from a sequence of benzidinediimine and diphenylene units with amino/amino end groups and thus proves the possibility of ammonia elimination during the oxidative polymerization of aromatic diamines. The method seems to be common for the synthesis of polymers with the sequence of aromatic diimine and arylene units. TGA analysis of the obtained trimer and polymer was investigated, and the high thermostability of both the polymer and trimer was revealed. According to the obtained data, both polymer and trimer matrix decomposition started at 300 °C, and at 600 °C, 75.94% and of 69.40% of the initial weight remained, correspondingly. Conductivities of the polymer and trimer show a semiconductor-type change from temperature and after doping show an increase in conductivity up to 10−4 Sm/cm.

Relation Between Local Structure, Electric Dipole and Charge Carrier Dynamics in DHICA Melanin, a Model for Biocompatible Semiconductors

2019 ◽  
Author(s):  
Micaela Matta ◽  
Alessandro Pezzella ◽  
Alessandro Troisi
Keyword(s):  
Electronic Structure ◽  
Degrees Of Freedom ◽  
Structural Model ◽  
Computational Study ◽  
Oxidative Polymerization ◽  
Radical Scavenging ◽  
Charge Carriers ◽  
Electronic Charge ◽  
Polymer Semiconductors ◽  
Synthetic Pigments

<div><div><div><p>Eumelanins are a family of natural and synthetic pigments obtained by oxidative polymerization of their natural precursors: 5,6 dihydroxyindole and its 2-carboxy derivative (DHICA). The simultaneous presence of ionic and electronic charge carriers makes these pigments promising materials for applications in bioelectronics. In this computational study we build a structural model of DHICA melanin considering the interplay between its many degrees of freedom, then we examine the electronic structure of representative oligomers. We find that a non-vanishing dipole along the polymer chain sets this system apart from conventional polymer semiconductors, determining its electronic structure, reactivity toward oxidation and localization of the charge carriers. Our work sheds light on previously unnoticed features of DHICA melanin that not only fit well with its radical scavenging and photoprotective properties, but open new perspectives towards understanding and tuning charge transport in this class of materials.<br></p></div></div></div>

Fabrication of Conductive Textile via Chemical Oxidative Polymerization of Aniline on Polyester Cloth

2018 ◽  
Author(s):  
alireza razaghi
Keyword(s):  
Acidic Solution ◽  
Oxidative Polymerization ◽  
Morphological Structure ◽  
Infrared Spectrometry ◽  
Aniline Monomer ◽  
Polyester Textile ◽  
Conductive Polyaniline ◽  
Conductive Textile ◽  
Polymerization Conditions ◽  
Aniline Polymerization

In this research aniline polymerization conditions were optimized in presence of pre-treated polyester textile to achieve as high electrical conductivity as 100 S/Cm. Alkaline activation of the polyester textile was followed by immersion in to aqueous acidic solution of aniline monomer. Then the oxidant solution was used to initiate the polymerization. Finally, the prepared product was washed and dried prior to ant test. Functional groups were studied by Fourie-transformed infrared spectrometry (FTIR) from the surface of the polyaniline coated textile. Also, morphological structure of synthesized conductive polyaniline was studied by scanning electron microscopy (SEM). The synthesized cloth was used in a closed circuit in order to light up alight emitting diode to emphasis the conductivity of the textile and fibres that synthesised by this method.

Fabrication of Conductive Textile via Chemical Oxidative Polymerization of Aniline on Polyester Cloth

2018 ◽  
Author(s):  
alireza razaghi
Keyword(s):  
Acidic Solution ◽  
Oxidative Polymerization ◽  
Morphological Structure ◽  
Infrared Spectrometry ◽  
Aniline Monomer ◽  
Polyester Textile ◽  
Conductive Polyaniline ◽  
Conductive Textile ◽  
Polymerization Conditions ◽  
Aniline Polymerization

In this research aniline polymerization conditions were optimized in presence of pre-treated polyester textile to achieve as high electrical conductivity as 100 S/Cm. Alkaline activation of the polyester textile was followed by immersion in to aqueous acidic solution of aniline monomer. Then the oxidant solution was used to initiate the polymerization. Finally, the prepared product was washed and dried prior to ant test. Functional groups were studied by Fourie-transformed infrared spectrometry (FTIR) from the surface of the polyaniline coated textile. Also, morphological structure of synthesized conductive polyaniline was studied by scanning electron microscopy (SEM). The synthesized cloth was used in a closed circuit in order to light up alight emitting diode to emphasis the conductivity of the textile and fibres that synthesised by this method.

Benzoxazine monomers based on aromatic diamines and investigation of their polymerization by rheological and thermal methods

2020 ◽  
Vol 138 (10) ◽  
pp. 49974
Author(s):  
Igor A. Sarychev ◽  
Vyacheslav V. Kireev ◽  
Vladimir V. Khmelnitskiy ◽  
Viktoria V. Vorobyeva ◽  
Anton S. Tupikov ◽  
...  
Keyword(s):  
Aromatic Diamines ◽  
Thermal Methods

scholarly journals Preparation and Gas Sensing Properties of PANI/SnO2 Hybrid Material

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1360
Author(s):  
Qiaohua Feng ◽  
Huanhuan Zhang ◽  
Yunbo Shi ◽  
Xiaoyu Yu ◽  
Guangdong Lan
Keyword(s):  
Hybrid Material ◽  
Room Temperature ◽  
Tin Dioxide ◽  
Gas Adsorption ◽  
Gas Sensing ◽  
Oxidative Polymerization ◽  
Environmental Pollutants ◽  
Decomposition Temperature ◽  
Benzene Vapor ◽  
Thermo Gravimetric Analyzer

A sensor operating at room temperature has low power consumption and is beneficial for the detection of environmental pollutants such as ammonia and benzene vapor. In this study, polyaniline (PANI) is made from aniline under acidic conditions by chemical oxidative polymerization and doped with tin dioxide (SnO2) at a specific percentage. The PANI/SnO2 hybrid material obtained is then ground at room temperature. The results of scanning electron microscopy show that the prepared powder comprises nanoscale particles and has good dispersibility, which is conducive to gas adsorption. The thermal decomposition temperature of the powder and its stability are measured using a differential thermo gravimetric analyzer. At 20 °C, the ammonia gas and benzene vapor gas sensing of the PANI/SnO2 hybrid material was tested at concentrations of between 1 and 7 ppm of ammonia and between 0.4 and 90 ppm of benzene vapor. The tests show that the response sensitivities to ammonia and benzene vapor are essentially linear. The sensing mechanisms of the PANI/SnO2 hybrid material to ammonia and benzene vapors were analyzed. The results demonstrate that doped SnO2 significantly affects the sensitivity, response time, and recovery time of the PANI material.

scholarly journals NIR responsive tumor vaccine in situ for photothermal ablation and chemotherapy to trigger robust antitumor immune responses

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Lirong Zhang ◽  
Jingjing Zhang ◽  
Lixia Xu ◽  
Zijian Zhuang ◽  
Jingjin Liu ◽  
...  
Keyword(s):  
Immune Responses ◽  
Tumor Vaccine ◽  
Oxidative Polymerization ◽  
Delivery Mode ◽  
Tumor Treatment ◽  
One Pot ◽  
Photothermal Ablation ◽  
Prolonged Retention ◽  
The One

Abstract Background Therapeutic tumor vaccine (TTV) that induces tumor-specific immunity has enormous potentials in tumor treatment, but high heterogeneity and poor immunogenicity of tumor seriously impair its clinical efficacy. Herein, a novel NIR responsive tumor vaccine in situ (HA-PDA@IQ/DOX HG) was prepared by integrating hyaluronic acid functionalized polydopamine nanoparticles (HA-PDA NPs) with immune adjuvants (Imiquimod, IQ) and doxorubicin (DOX) into thermal-sensitive hydrogel. Results HA-PDA@IQ NPs with high photothermal conversion efficiency (41.2%) and T1-relaxation efficiency were using HA as stabilizer by the one-pot oxidative polymerization. Then, HA-PDA@IQ loaded DOX via π-π stacking and mixed with thermal-sensitive hydrogel to form the HA-PDA@IQ/DOX HG. The hydrogel-confined delivery mode endowed HA-PDA@IQ/DOX NPs with multiple photothermal ablation performance once injection upon NIR irradiation due to the prolonged retention in tumor site. More importantly, this mode enabled HA-PDA@IQ/DOX NPs to promote the DC maturation, memory T cells in lymphatic node as well as cytotoxic T lymphocytes in spleen. Conclusion Taken together, the HA-PDA@IQ/DOX HG could be served as a theranostic tumor vaccine for complete photothermal ablation to trigger robust antitumor immune responses.

Bifunctional citrate-Ni0.9Co0.1(OH)x layer coated fluorine-doped hematite for simultaneous hole extraction and injection towards efficient photoelectrochemical water oxidation

Nanoscale ◽  
2021 ◽  
Author(s):  
Peng Wang ◽  
Feng Li ◽  
Xuefeng Long ◽  
Tong Wang ◽  
Huan Chai ◽  
...  
Keyword(s):  
Surface Modification ◽  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
Water Oxidation ◽  
Surface Oxygen ◽  
Co Catalyst ◽  
Photoelectrochemical Water Oxidation

Surface modification by loading a water oxidation co-catalyst (WOC) is generally considered to be an efficient means to optimize the sluggish surface oxygen evolution reaction (OER) of hematite photoanode for...

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