Effect of solvent’s polarity on the structure of polyhydroxybutyrate

The authors study the process of making the polymer materials of the required set of service properties using various types of chemical, physical or physico-chemical modifications at the stage of raw materials preparation or in the process of molding products. It is noted that there is a radical change in the structure of the polymer material at various levels of structural organization. In this regard, there is need to establish the relationship between factors which influence and change the structural parameters of the polymeric material. Establishing such relationships allows to purposefully change the properties of the polymeric system depending on the application area of this product. As a rule, most of the biopolymers of bacterial origin are very sensitive to high temperatures. This is especially important for medical products, for example, matrices for controlled release of drugs because the introduction of drugs into the polymer is carried out mainly through the solution. The authors found out that with increasing polarity of the solvent and refinement of the crystal structure the decrease in the proportion of the amorphous phase of PHB took place. It is shown that the proportion of defective crystalline phase in the films of PHB is directly proportional to the cohesive energy of the solvent.