STARCH ALKANOATES AS MODELS FOR THERMOPLASTIC POLYSACCHARIDES

The low degree of internal molecular mobility of stiff polysaccharide chains prevent any thermal transition in the temperature range of thei r chemical stability. Substituted starches were synthesised to find th e structural range, i.e. the necessary amount and length of mobile sid e chains which support the molecule with high enough level of internal degrees of freedom. Esterification and transesterification with hydro xy alkanoates, their polymers and lactones were used. The reaction was best catalysed with strong delocalised bases. The thermal properties of these model substances were characterised.