Improving the thermal stability of different types of xylan by acetylation

• The impact of various degrees of acetylation on improving the thermal stability of xylan isolated from different botanical source has been studied; methylglucuronoxylan from birch and eucalyptus, arabinoglucuronoxylan from spruce and glucuronoarabinoxylan from sugarcane bagasse and straw. The lower molecular weight of nonacetylated methylglucuronoxylan (17.7-23.7 kDa) and arabinoglucuronoxylan (16.8 kDa) meant that they were more soluble in water than glucuronoarabinoxylan (43.0-47.0 kDa). The temperature at the onset of degradation increased by 17-61 degrees C and by 75-145 degrees C for low and high acetylated xylans respectively, as a result of acetylation. A glass transition temperature in the range of 121-132 degrees C was observed for the samples non-acetylated and acetylated at low degree of acetylation (0.0-0.6). The acetylation to higher degrees (1.4-1.8) increased the glass transition temperature of the samples to 189-206 degrees C. Acetylation proved to be an efficient method for functionalization of the xylan to increase the thermal stability.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Kemiteknik -- Polymerteknologi (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Chemical Engineering -- Polymer Technologies (hsv//eng)

Nyckelord

Acetylation

Hardwood

Molecular weight

Softwood

Sugarcane residues

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)