STRUCTURE AND THERMAL BEHAVIOR OF TANNINS FROM Acacia dealbata BARK AND THEIR REACTIVITY TOWARD FORMALDEHYDE
The objective of this study was to evaluate the tannin extraction potential taken from the bark of Acacia dealbata. This tannins were extracted with water at 90°C. An extraction yield of 17.2% solids with a Stiasny number of 82% was obtained from the bark extract of Acacia dealbata. The structure was studied by Fourier transform infrared spectroscopy (FTIR). The thermal behavior of tannins was studied by DSC and a glass-transition temperature (Tg) of 116,77°C was determined. The thermal stability of tannins was studied by TGA. At 196.91°C the decomposition is 3.7% and the maximum of the weight loss rate (DTG) of the degradation was 257.77°C. The curing with formaldehyde showed an exotherm reaction in the range of 100-120°C, which is similar to tannins of other species.
Main Authors: | , , |
---|---|
Format: | Digital revista |
Language: | English |
Published: |
Sociedad Chilena de Química
2016
|
Online Access: | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072016000400007 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|