Investigation of the mechanical properties of graft copolymers of gelatin with synthetic polymers and their mixtures

A study was made of the mechanical properties of graft copolymers of gelatin with polyacrylonitrile (PAN) and with polybutylacrylate (PBAC), and these were compared with those of pure gelatin. The experimental results show that the elasticity of the system is increased by grafting of the flexible chain PBAC, while the grafting of PAN leads to increased rigidity. For graft copolymers of gelatin with PBAC it was found that shrinkage in the course of heating to 120° is greatly reduced, and this reduction is attributed to the formation of a microheterogeneous structure, the disperse phase of the latter including gelatin and PBAC in its composition. Model mechanical mixtures consisting of these components with approximately the same degree of dispersion of PBAC show shrinkage behaviour during heating to 120° resembling that of pure gelatin.