Mimosa and chestnut tannin extracts reacted with hexamine in solution

• Published in: Journal of thermal analysis and calorimetry 2009-05, Vol.96 (2), p.515-521
• Main Authors: Peña, C., de la Caba, K., Retegi, A., Ocando, C., Labidi, J., Echeverria, J. M., Mondragon, I.
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Application fields; Applied sciences; Chemistry; Chemistry and Materials Science; Chestnut; Differential scanning calorimetry; Ethers; Exact sciences and technology; Hexamine; Infrared spectroscopy; Inorganic Chemistry; Measurement Science and Instrumentation; Organic polymers; Physical Chemistry; Physicochemistry of polymers; Polycondensation; Polymer industry, paints, wood; Polymer Sciences; Preparation, kinetics, thermodynamics, mechanism and catalysts; Tannins; Technology of polymers; Thermal analysis
• ISSN: 1388-6150; 1588-2926; 1572-8943
• DOI: 10.1007/s10973-007-8352-9

Autocondensation reactions of mimosa and chestnut tannin extracts solutions have been analysed at several pH by differential scanning calorimetry (DSC). Alkaline pH promotes autocondensation reaction of these tannins. Curing reactions between these tannins and hexamine at acid and not strongly alkaline pH have been proved by DSC. Thermal analysis gives insights not only on reactions between tannin and hexamine, but also about water presence on solutions and degradation reactions of tannins. Products obtained from reactions between tannins and hexamine have been analysed by Fourier transform infrared spectroscopy (FTIR). The obtained chemical structures are influenced by both chemical structure of tannin and pH of solution. For mimosa tannin amine and ether groups are obtained while for hydrolysable chestnut tannin amide groups have been detected.