چکیده
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A polystyrene‐modified epoxidized novolac resin/montmorillonite nanocomposite
was fabricated and characterized successfully. For this purpose, novolac resin (NR)
was epoxidized through the reaction of phenolic hydroxyl group with epichlorohydrin
in super basic medium to produce epoxidized novolac resin (ENR). Afterward,
a polystyrene was synthesized by atom transfer radical polymerization (ATRP) technique,
and then brominated at the benzylic positions using N‐bromosuccinimide
(NBS). The brominated polystyrene (PSt‐Br) was reacted with ethanolamine in basic
medium in order to afford an amine‐functionalized polystyrene (PSt‐NH2). An
organo‐modified montmorillonite (O‐MMT) was synthesized through the treatment
of MMT with hexadecyl trimethyl ammonium chloride salt. Finally, ENR‐PSt/MMT
nanocomposite was fabricated through curing a mixture of ENR (70 wt.%) and OMMT
(5 wt.%) with PSt‐NH2 (25 wt.%). Transition electron microscopy (TEM) and
powder X‐ray diffraction (XRD) analysis revealed that the fabricated nanocomposite
has an exfoliated structure. Thermal property studies using thermogravimetric
analysis (TGA) showed that the curing of ENR by PSt‐NH2, as well as incorporation
of a small amount of MMT have synergistic effect on the thermal stability of the
ENR resin.
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