Abstract
A series of PVC films stabilized with novel antimicrobial itaconimido aryl 1,3,4-oxadiazoles (D1'-D4'), at absence or presence of various concentrations of multiwalled carbon nanotubes (MWCNTs), was prepared by a conventional solution casting method. D1'-D4' was prepared via thermal cyclization processes by loss of water for their congruous predecessors itaconimido aryl hydrazides. Elemental analysis and various spectroscopy measurements were used to prove their structures. D1'-D4' have great antimicrobial activities and some of them showed similar or sometimes higher impact than the reference antibiotic. From TG measurements in nitrogen, they have high thermal stabilities and their decomposition temperatures were above 275-310 degrees C in accordance with substituent groups NH2 and/or OH incorporated into their structures. They have higher thermal stabilizing efficiencies for PVC in comparison with some industrial thermal stabilizers. Inclusion of 0.1-0.5 wt% MWCNTs into PVC films, that were stabilized with D4', enhanced the composites thermal stability. XRD, SEM as well as TEM were used for ascertaining of incorporation and well dispersion of MWCNTs into PVC matrices. Additionally, the efficacy of stabilization has been proven via a decreased rate of color alteration, mechanical properties change and chains cleavage for PVC. The high antimicrobial and thermal characteristics of these stabilizers afford them a great possibility to secure antimicrobial thermally stable PVC composites. Also, improvement of thermal and mechanical properties of PVC stabilized by D4' after its incorporation with MWCNTs afford a great possibility to its application in different fields where their thermal resistance and high tensile strength resistance play a very important role.