Condensation polymers, microhardness

Bearing in mind the outlined peculiarities of condensation polymer blends, and particularly when they consist of one component and one phase (this case is more the exception rather than the general rule since block copolymers usually consist of two, three, or more phases), the application of the additivity law for the evaluation of their characteristics does not seem to be completely justified. The observed good agreement between the measured microhardness values and the calculated ones (Fig. 5.7) allows one to make an important conclusion in this respect. 

The use of the microhardness technique in blends of condensation polymers [PET/PEN and PET/polycarbonate (PC)] evidences the formation of copolymer sequences within the blends (30). 

Balta Calleja F J, Fakirov S, Roslaniec Z, Krumova M, Ezquerra T A and Rueda D R (1998) Microhardness of condensation polymers and copolymers. 2. Poly(ester ether carbonate) thermoplastic terpolymers, J Macromol Sd-Phys B37 219-237. 

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