Preparation of graphene oxide/bio-based elastomer nanocomposites through polymer design and interface tailoring

Bio-based poly(dibutyl itaconate-ter-isoprene-ter-4-vinylpyridine) (PDBIIVP) elastomers with different 4-vinylpyridine (4-VP) contents were synthesized by redox emulsion polymerization for the purpose of designing and preparing green graphene oxide (GO)/PDBIIVP nanocomposites with strong interfacial interaction. The ionic bonding interfaces in the nanocomposites were the result of electrostatic attraction between the in situ protonated pyridine groups of PDBIIVP and the electronegative GO sheets with hydrochloric acid during latex co-coagulation and were confirmed by X-ray photoelectron spectroscopy. The inclusion of a small amount of 4-VP (less than 7 wt%) improved the dispersion of GO, the interfacial interaction between PDBIIVP and GO, and the performance of the GO/PDBIIVP nanocomposite markedly. The reinforcement effects of GO on the mechanical and gas barrier properties of PDBIIVP increased continuously with increasing 4-VP content. Additionally, GO/PDBIIVP nanocomposites with a fixed 4-VP content and different GO loadings were prepared and characterized. As the GO loading increased, the performance of the nanocomposites improved greatly. For the GO/PDBIIVP with 7.0 wt% of 4-VP and 4 phr of GO, the tensile strength increased by 700%, the volume loss of abrasion decreased by 53%, and the gas permeability decreased by 63% compared with those of the neat PDBIIVP. The remarkable improvements are attributed to the strong ionic bonding interfaces between the pyridine-included bio-based elastomer and GO. We believe that this work of new polymer construction with the functional group targeting the interfacial interaction with GO should be an important strategy for developing GO-based polymer nanocomposites with high performance.