Synthesis and Characterization of Sunflower Oil-Based Polysulfide Polymer/Cloisite 30B Nanocomposites

Abstract

<em>In current work, halogenated sunflower oil was reacted with Na₂S₃ to produce sunflower oil-based polysulfide polymer. Cloisite 30B as organomodified nanoclay was used in different contents to investigate its effect on the properties of the synthesized polymer. All nanocomposites were prepared via in situ polymerization method in aqueous media. Fourier Transform-InfraRed (FT-IR) spectroscopy revealed the inclusion of nanoclay in a polymeric matrix.</em><em>X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) were used to study the degree</em><em> of intercalation/exfoliation of nanoplatelets in matrices. Proton Nuclear Magnetic Resonance (¹H NMR) was utilized to study the molecular weight of synthesized polymers. Thermal stability of nanocomposites was determined by means of Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) was used to investigate thermophysical properties. According to results, nanocomposite with 1 wt. % of Cloisite 30B showed an exfoliated morphology whereas the higher amount of nanoclay resulted in intercalated nanoplatelets with different degrees of intercalation. Also, adding more Cloisite 30B nanoplatelets led to more decrease in molecular weight. After the introduction of nanoclay into nanocomposites structure and increasing its content, the thermal stability of nanocomposites was improved whereas no significant improvement of thermal stability was observed by increasing clay content from 3 to 5 wt. %. Also, all samples showed only the glass transition temperature (T_g) and no distinct peak related to melting was observed. Adding more nanoclay resulted in higher T_g value due to the confinement effect of nanoplatelets</em><em>.</em>