Thermal Stability of PVC with γ-APS-g-MMT and Zeolite Stabilizers by TGA Technique

Abstract

In this work, hexadecyltrimethylammonium bromide modified montmorrillonite (OMMT), 3-aminopropyltriethoxysilane-grafted montmorrillonite (γ-APS-g-MMT), and zeolite were used as thermal stabilizers in PVC compound. The thermal stabilities of PVC were then assessed in terms of decomposition temperatures by thermal gravimetric analysis. X-ray diffractometer (XRD) was used to characterize the d-spacing of MMT as a result of γ-APS modification. The XRD results suggested that the d-spacing of silicate layers could increase with a chemical grafting of γ-APS molecules onto MMT. The zeolite was found to be the most effective stabilizer for PVC as compared with OMMT and γ-APS-g-MMT stabilizers. It was found that the greater the zeolite and γ-APS-g-MMT loadings in PVC compound, the higher the decomposition temperatures up to 7 phr. No synergic effect was observed on thermal stabilities of PVC by incorporating a mixture of γ-APS-g-MMT and zeolite stabilizers in PVC compound.

Keywords

thermal stabilization γ-APS-g-MMT zeolite PVC thermal properties mechanical properties.

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