Abstract
In this study were synthesized some polyurethanes based on polycaprolactone diol (PCL) with Mw=2000g/mol and 4,4’-diphenylmethane diisocyanate (MDI), using as chain-extending agents different linear diols with methylene number between 2 and 6, without adding catalysts. Effect of the diisocyanates concentration and chain extender structures on the polyurethanes has been discussed with reference to the thermal stability and mechanical properties. The physical and mechanical properties (hardness, stress-strain, resilience, abrasion resistance, etc.) of these polymers were measured according to standard methods. All the polymers were characterized by conventional methods. Thermal analysis (TGA and DSC) were used for characterization. The structures were confirmed by infra-red analysis (IR). The results showed that the thermal stability and mechanical properties of the final products can be controlled by the amount of the MDI and/or of the chain extenders nature. Keywords: polyurethanes, mechanical properties, thermal stability