Rapeseed straw as a renewable source of hemicelluloses: Extraction, characterization and film formation.
Polymeric hemicelluloses were extracted by autohydrolysis and alkali from a biomass feed consisting of the stems of rapeseed straw according to a full statistical factorial screening design. Water extraction yielded fractions rich in galactoglucomannan, while alkaline extraction yielded primarily xylan. The extracted galactoglucomannan and xylans had similar molecular weights, while the yield of xylan was higher than the yield of galactoglucomannan. The extracted hemicellulose fractions also contained some lignin (7-15%) and traces of Ca, K, Na, and Si. Free-standing films were prepared from the hemicellulose fractions with different xylan:galactoglucomannan ratios. The rapeseed xylan films showed strain-to-break values >60% without any added plasticizers.
Fiber and Polymer Technology, Royal Institute of Technology (KTH), Teknikringen 56, SE-100 44 Stockholm, Sweden.
Antonia
A
Svärd
Fiber and Polymer Technology, Royal Institute of Technology (KTH), Teknikringen 56, SE-100 44 Stockholm, Sweden.
Elisabet
E
Brännvall
Fiber and Polymer Technology, Royal Institute of Technology (KTH), Teknikringen 56, SE-100 44 Stockholm, Sweden. Electronic address: edlund@kth.se.
Ulrica
U
Edlund
D029741:Brassica rapa / Q000737:chemistry*; D005591:Chemical Fractionation / Q000379:methods*; D055595:Mechanical Phenomena; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification*
D011134:Polysaccharides; C007916:hemicellulose
Alkaline extraction; Autohydrolysis; Extraction; Film; Glucomannan; Rapeseed/canola straw; Xylan