Assessment of susceptibility to hydrolytic degradation of different types
of polyurethanes in terms of their use as biomaterials
Polimery 2013, No 4, 282
Polyurethanes (PUR) were synthesized in the reaction of 4,4'-diphenylmethane diisocyanate (MDI), 2,4- or 2,6-tolylene diisocyanate (TDI) with poly(oxyethylene) glycol (PEG) or poly (e-caprolactone) diol (PCL, with different molecular weight) using 2,2,3,3-tetrafluoro-1,4-butane-1,4-diol (TEBD) or 1,4-butanediol (BD) as a chain extender. In order to assess the possibility of using the synthesized PUR elastomers as biomaterials, they were subjected to the action of physiological salt solution at 37 °C. The structure of PUR before and after the incubation was identified by NMR, the loss of weight and thermal properties were determined by TG, DTG and DSC methods. Surface studies were also performed using microscopic and goniometric methods. It was found that the type of raw material has a significant effect on the surface properties of the obtained PUR elastomers and it determines the physical interactions within the structure, thus affecting the values of the surface free energy (SFE), surface roughness, hydrolytic degradation level (determined from the weight loss), thermal stability and glass transition temperature.