| dc.description.abstract | The composites of ethylene vinyl acetate/ natural rubber/ potash feldspar (EVA/NR/PF)
were studied. The composites were prepared by using Brabender Plasticoder at 160°C
with 50rpm of the rotor speed. The effect of PF loading, various types of
compatibilizers, and coupling agents on mechanical properties, swelling behaviour,
morphology properties, thermal properties, spectroscopy infrared, and XRD
characterization of the composites were investigated. In this study, 70 phr of ethylene
vinyl acetate and 30 phr of natural rubber were used as the polymer matrix. Meanwhile,
potash feldspar with 5, 10, 15, 20, and 25 phr was used as filler. Polyethylene-graftedmaleic
anhydride (PE-g-MAH), the combinations of isophthalic acid and maleic
anhydride (IAMA), ethylene vinyl acetate- grafted- phthalic anhydride (EVA-g-PAH),
and ethylene vinyl acetate- grafted- benzyl urea (EVA-g-BU) were used as
compatibilizer while silane coupling agent and glycolic acid- maleic anhydride (GAMA)
were used to modify the surface of PF. The addition of PF into EVA/NR
composites has reduced the tensile strength, elongation at break, percentage mass swell,
and interparticle spacing but improved modulus at 100% elongation (M100) and
percentage of crytallinity. The tensile fractured surface morphology had illustrated
agglomerations of PF at higher PF loading. At higher PF loading, the thermal stability
of the composites was found higher as temperature of decomposition and residual were
higher at higher PF loading. The compatibilized composites with PE-g-MAH, IAMA,
EVA-g-PAH, and EVA-g-BU showed an average of 3.19%, 4.72%, 11.24%, and 21.39%
respectively higher in tensile strength; 5.52%,23.69%, 38.49%, 21.25% respectively
higher in M100 than EVA/NR/PF composites. However, 3.97%, 5.51%, 6.24%, and
3.02% lower in elongation at break and 8.10%, 3.18%, 3.37%, and 3.66% lower in mass
swell percentage had been reported in PE-g-MAH, IAMA, EVA-g-PAH, and EVA-g-
BU compatibilized composites respectively compared to EVA/NR/PF composites.
Besides, the compatibilized composites presented higher thermal stability but lower
percentage of crystallinity, and interparticle spacing compared to EVA/NR/PF
composites. PF was treated with silane coupling agents and GA-MA in ethanol. The
increment of an average of 10.78% and 13.66% in tensile strength and 77.79% and
14.68%, in M100 were reported in EVA/NR/PFSilane and EVA/NR/PFGA-MA composites
respectively while the elongation at break and mass swell were decreased for the
composites. EVA/NR/PFSilane and EVA/NR/PFGA-MA composites exhibited lower
percentage of crystallinity and interparticle spacing but higher thermal stability in
comparison to EVA/NR/PF composites. The SEM morphology for all the
compatibilized and treated composites exhibited rough surface and indicated that the
interfacial adhesion had been improved. | en_US |
