مرکز منطقه ای اطلاع رساني علوم و فناوري -

چكيده لاتين :

Polyurethane elastomers with improved crystallinity and hydrophilicity were synthesized by step growth polymerization techniques using polyfs-caprolactcne) (PCl) and 4,4י-diphenylmethane diisocyanate (MOl), extended with a,co alkane diols (hydroxyl group attached with first and last methylene unit of an alkane chain). Structural characterizations were performed using FTIR, 1H NMR and 13C NMR techniques. Crystallinity of the polyurethane (PU) films was studied and discussed by using X-ray diffraction technique. For all the samples, the crystallinity and hydrophilicity were found to increase with increasing of the chain extender length. Optimum crystallinity and hydrophilicity were obtained from elastomer extended with 1,1O-decane diol (000) in comparison to elastomers extended with 1,2-ethane diol (EOO). Contact angle measurement, water absorption and swelling behaviour of the synthesized polyurethane were affected by number of methylene units in the chain extenders in the resulted PU. Investigation of structure-property relationship for prepared elastomers showed that the main determining factors for observed properties were degree of crystallinity, hydrophilicity and chain extender length in the PU backbone