U. Funke et al., PROCESSING AND CHARACTERIZATION OF BIODEGRADABLE PRODUCTS BASED ON STARCH, Polymer degradation and stability, 59(1-3), 1998, pp. 293-296
Different types of starch were processed in blend systems with natural
plasticizers and commercial fibres by conventional extrusion and inje
ction moulding techniques. Processing conditions and product qualities
differed widely according to the kind of starches and additives used.
Starch polymer characteristics, i.e. amylose/amylopectin ratio and mo
lecular mass distribution, were studied in native and extruded samples
in order to reveal structural effects on product quality. As a result
it could be shown that thermomechanical treatments of starch caused s
ignificant depolymerization, especially of the amylopectin fraction, w
hile the amylose fraction remained stable. Considerable improvements i
n product properties were achieved by adding small amounts of fibres t
o the starch samples. Blend systems with 2-7% fibres resulted in an in
crease of tensile strength and water resistance of these products. (C)
1998 Elsevier Science Limited. All rights reserved.