Characterization of styrene-co-butyl acrylate/Cloisite Na+ nanocomposite film synthesized via soap free emulsion polymerization

• Soap free emulsion polymerization (Pickering) was used for armored latex synthesis.
• Barrier films of armored latex nanoparticles of STY-co-BA/Cloisite Na+ were prepared.
• XRD and TEM confirmed exfoliated and intercalated structures of barrier films.
• The barrier performances against oxygen and water vapor increased very well.
• By increasing the clay percentage, increased barrier performances was observed.

The formation of stable armored styrene-co-butyl acrylate/Cloisite Na+ latex particles up to 250 nm which was synthesized by soap free emulsion polymerization method and thereafter, characterization of derived nanocomposite films was studied by many analysis such as transmission electron microscopy, low angle X-ray diffraction, Oxygen Transmission Rate (OTR), water vapor transmission rate (WVTR), water uptake and contact angle. The results of this research work revealed exfoliated nanoclay structure for the samples containing 6 and 8 wt% Cloisite Na+ and intercalated nanoclay structure for sample containing 10 wt% Cloisite Na+. The barrier properties of these clear films processed from aforementioned latexes was according to the well dispersion of clay layers within the nanocomposite matrix. Drastic reduction of OTR and WVTR were observed by increasing the clay loading up to 10 wt%. The increase in tensile strength and Young’s modulus of nanocomposite films showed high effects of nanoclay on the film mechanical properties, mainly due to the presence of the delaminated clay layers regularly all within the styrene-co-butyl acrylate/Cloisite Na+ matrix. However, the contact angle values for the crude copolymer film (styrene-co-butyl acrylate film) and its’ nanocomposites film (styrene-co-butyl acrylate/Cloisite Na+ film) did not show any distinguished changes and were almost equal in value.