Analisa Sifat Fisikokimia Tanin Kulit Akasia Mangium Untuk Bahan Baku Perekat

Abstract

Tannin is a  derivative from organic compound from glycosides found in various plants, the most important commercial condensed tannin oblained from gymnosperms species for example Acacia mangium. Tannin is one of the  adhesive  materials  that  can have  a  dimensional stability  of  wood. Tannin contains flavonoid compounds that have hydroxyl groups that are reactive to condense against   other materials   as a cross-link agent, like formaldehyde, which may increase the number of polymer units of tannins, thus increasing the bonding strength of tannin based adhesives. Based on the results of physicochemical analysis of extracts (tannins) from the bark of A. mangium  as a raw material for adhesives, it can be concluded  that the A.  mangium tannin   had a higher reactivity toward formaldehyde of 96%,  reactivity  of  tannin  toward  hexamefhylene  tetramine  of  46.18%, tannins toward ethylene glycol of 3.07% and tannins toward dimethylol urea of   183.59%.    Meanwhile,   the   value  of   reactive   polyphenol   content determined by UV-Method showed in tannin with formaldehyde of 97.65%, tannins with hexamethylene tetramine of 46%,  tannins with ethylene glycol of 2%,  and tannins with dimelhylolurea of 56.26%.   The resuits of gelation time   (gel time) measurements fullfilled the requirements of JIS K 6833-1980 by the treatment of hexamelhylenen tetramine for variable II and III, and  the treatment of ethylene glycol (variable VI). The viscosity values by the  Ireatment of hexamethylenen  tetramine (variable II, III, and  IV), for ethylene glycol (variable II  -  VI)  met the requirement conditions  by JIS K 6833-1980.