Studies on N-methylene phosphonic chitosan/poly(vinyl alcohol) composite proton-exchange membrane

Microwave assisted rapid synthesis of N-methylene phosphonic chitosan via Mannich-type reaction

“…This intermediate, N-methyl and N, N′-dimethyl chitosan reacted with phosphorus acid in 1:1 stoichiometric ratio to form respective methylphosphonic amine.Different research groups also evidenced the formation of NMPC in accordance to the scheme proposed byLebouc et al (2005) via refluxing(Lebouc, Dez & Madec, 2005;Rodrìguez, Albertengo, Etcheverry & Schulz, 2005;Ramos et al, 2006;Binsu, Nagarale, Shahi & Ghosh, 2006;Saxena, Kumar & Shahi, 2006;Datta, Dhara & Chatterjee, 2012).Recently, Illy et al (2014) reported formation of only side products as N-methyl and N,N-dimethyl chitosan. Here, in present study, Kabachnik-Fields reaction modified with MW irradiation (figure 1), where it provide rapid and uniform energy to the reaction system along with removal of water as reaction carried out in an open system.…”

“…NMPC has been reported as an isoniazide prodrug against Mycobacterium tuberculosis availing its immune stimulating macrophage activity and enhanced humoral response towards infected cells (Rando, Brandt & Ferreira, 2004). Further, the improved ionogenic property of NMPC is employed as a proton exchange membrane for fuel cell applications (Binsu, Nagarale, Shahi & Ghosh, 2006).…”

Thermal Stability and Degradation of Chitosan Modified by Cinnamic Acid

“…To increase water solubility, the chemical modifications of chitosan have been applied [1]. The free amino groups of chitosan enable a veriety of chemical modifications and substitution process like carboxyalkylation, acylation, sulfation, cyanoethylation, nitration, phosphorylation, enzymatic substitution, metal chelation, Schiff's base, etc [2][3][4][5]. Furthermore, various properties of the modified chitosan have been used in many applications such as absorption enhancement in caco-2-merbane model [6], gene [7], drug or protein delivery [8,9], waste-water treatment [10], food industry [11], gel implants [12], scaffolding material [13] and in medicine as wound dressing and drug delivery [14,15].…”

Chitosan Based Membranes for Separation, Pervaporation and Fuel Cell Applications: Recent Developments

“…Polymer electrolyte complexes of CS and poly vinyl phosphonic acid (PVPA) were prepared by in situ polymerization of vinyl phosphonic acid (VPA) in CS matrix [123]. Polybenzamidazole (PBI) and sulfuric acid (H 2 SO4) composite membranes were prepared and the exclusion problem was observed especially in PBI/H 3 PO 4 composite membranes [124]. Sulfonated polysulphone (SPSF) /CS exhibited high IEC and proton conductivity higher than Nafion 117 at temperature above 100°C.…”