One of the general ways to study thermal properties of materials is differential scanning calorimetry (DSC). Analysis of DSC thermograms allows to evaluate numerous parameters - glass transition temperature, moisture loss temperature, thermal degradation of material, melting temperature etc. However, there is a lack of materials on the analysis of thermograms of cellulose-containing samples and artifacts, that may occur on it (doubled maximums, changes of maximums according to type of sample or additives etc). To open the discussion, the first artifact in maximum interpretation is provided on Fig.1.1. On thermogram of bacterial cellulose sample with hemicellulose additive (Fig.1.1.) two maximums occur at the region of cellulose degradation. However, it is not clear, whether the observed maximums are dedicated both to cellulose degradation or not. This two maximums appear for some probes, but for some probes we may see only one maximum. What may be the reason?
The other point in the analysis of thermograms of polysaccharide samples is the zone on Fig.1.2. It is non-alalyzed zone. However, the endothermicity is clear that means that some processes are stilltake place. Thus, that is an another point of controversies in the analysis of thermograms.
So, we appreciate very much your help on this questions and sharing the knowledge. And also many thanks for sharing some articles, books or standard operational procedures on the analysis of thermogram of polysaccharides.
Dear Vadym Chibrikov, what looks like artifacts in the DSC thermograms and other analysis techniques are not. Biopolymers in general have such features due to many influencing factors on the internal structures and chains order. Among the most cited are the origins of the polysaccharides, water content and its interactions, degree of crystallinity/amorphousness, and other. Further details from the following book, from which the attached chapter is extracted. My Regards
Thermal Properties of Green Polymers and Biocomposites, Tatsuko Hatakeyama, Hyoe Hatakeyama (2005)
Abdelkader BOUAZIZ Thank you, Sir! You are definitely right - the term "artifacts" is, of course, in this case, out of the scale, related to the measurement technique. Conditions of thermogram capturing are almost the same in our field. Thus, it is definitely the question of the sample and its "conditions", which provide to such a thermal response of it. A lot of thanks for the Chapter!
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