Tezislər / Theses

parts of various plants, starch has been of great interest in recent years 
because of its environmental friendliness. Starch is such a polymer which is 
constituted by the linkage of amylose (20-30%) and amylopectin (70-80%) 
with various percentages, depending on the type. Starch macromolecules 
has the consistency of hydrogen bonds which induces the diminishments in 
the mobility of these molecules, consequently native starch becomes hard to 
be processed. To manufacture higher qualified productions, cellulose plays 
an important role in terms of dealing with the problem pertaining to hardness 
in processing. Cellulose is also another raw material which is linear polymer 
of anhydroglucose being the most common substance on the planet; moreover, 
since it is highly economical, reasonably priced and ecologically friendly, 
cellulose is broadly applied in packaging industry, as well. Nevertheless, some 
evident drawbacks of starch and cellulose mixture to exist drives new 
wayouts to be explored, which concludes the addition of plasticizers, namely 
polyols (especially, sorbitol, glycerol and ethylene glycol) and 
monosaccharides (mannose, glucose, fructose) (Farahnaky A. et al 2012). 
The primary functions of the additives are to change the ability to absorb 
moisture content, to increase the flexibility level of films, to decrease 
intermolecular interactions of chains. Additionally, when starch films are dried 
in ambient environments without plasticizers, they collapse into pieces. In 
both monosaccharides and polyols, the main components that affect the 
change in the properties of raw materials are hydroxyl groups. To be more 
elaborated, these hydroxyl groups are interracted with the hydrogens of raw 
materials. In addition, starch and cellulose granules experience gelanization 
process, and during this procedure, amylose and amylopectin molecules are 
released into solution which results in the higher flexibility quality of the 
production. This operation leads the developments in the properties, such as 

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