Propyl methacrylate(MPTMS)-intercalatedMg-Al-layered double hydroxide: II.Morphological, thermal propertiesand diffusion behavior

Abstract

A series of poly (vinyl chloride) (PVC) composites have been madethrough an in-situ suspension polymerization process in attendanceof 5 wt% of MgAl(NO3) layered double hydroxide (LDH) or 3-(trimethoxysilyl) propyl methacrylate (MPTMS)-intercalated Mg-AlLDH (MPTMS-LDH). The thermal stability and mechanical and phys-ical properties of the prepared composite samples were examined andcompared with the pure PVC. The data obtained from the Brabender®plastograph illustrated that the final PVC grains prepared in atten-dance of MPTMS-LDH have higher thermal stability time and lowerfusion. The fusion degree of PVC particles has been incremented byMPTMS-LDH nanosheet; as a result, it has been observed that alower requirement of temperature/time process. A conventional dehy-drochlorination test proved the improvement of thermal stability. The composite, including MPTMS-LDH, showed a 40% improvement indehydrochlorination rate relative to the pure PVC, this enhance-ment is 12% in comparison with PVC/LDH composite. TGA curvesshow that the 5 and 50% weight loss temperatures of PVC resinshave remarkable growth (∼11 ◦C) with introducing 5 wt% LDH orMPTMS-LDH. The storage modulus of the glassy state(glassy plato)and the Tg of the PVC/MPTMS-LDH is higher than the pure PVCand composite of PVC/LDH. The results of mechanical analysis illus-trated that PVC/LDH-MPTMS composites have larger stiffness andtoughness. The Charpy notched impact strength, tensile strength, andYoung’s modulus of the PVC/LDH-MPTMS composites are signifi-cantly more than the composite of PVC/LDH and the pure PVC.