One-pot exfoliation and surface functionalization of MoS2: a potential nanofiller to overcome the brittleness of polystyrene (PS).
FIEL, Rodrigo; BARCELOS, Ingrid D.; GONÇALVES, Ricardo H.; SOARES, Mario R. S.; ROCHA, Gabriel; SILVA, Caio M. P.; MASTELARO, Valmor Roberto; LEITE, Edson R.
FIEL, Rodrigo; BARCELOS, Ingrid D.; GONÇALVES, Ricardo H.; SOARES, Mario R. S.; ROCHA, Gabriel; SILVA, Caio M. P.; MASTELARO, Valmor Roberto; LEITE, Edson R.
Abstract: In this communication, we describe a simple one-pot approach to exfoliate and functionalize MoS2 (f-MoS2) via liquid-phase exfoliation (LPE) starting from bulk MoS2 dispersed in styrene/N-methyl pyrrolidone (NMP) solution using azobisisobutyronitrile (AIBN) as a radical initiator. The colloidal stability of f-MoS2 is achieved due to an in situ radical polymerization of styrene and functionalization on the edge sites of MoS2. Thermogravimetric analysis (TGA) showed the presence of 8.23 wt% of functionalized MoS2. The f-MoS2 was then incorporated in polystyrene (PS) matrix at different loadings (15 wt%, 30 wt% and 60 wt%) by a solution-based process using toluene as solvent. The f-MoS2/PS nanocomposites exhibited a good polymer/nanofiller interfacial interaction and promoted significant thermal stabilization in PS increasing, in our best case, the T-5% and T-50% temperatures by 91 °C and 15 °C, respectively, compared to neat PS. When increasing the f-MoS2 loading, we also noticed a dramatic decrease on the glass transition temperature (Tg) of the f-MoS2/PS nanocomposites, which has a direct correlation on its mechanical properties. As f-MoS2 loading increases the Young's modulus decreases, compared to neat PS. However, at 60 wt% f-MoS2 loading, the nanocomposite showed basically the same Young's modulus of neat PS and the strain at break increased more than a 150%, which indicates a significant load transfer between the polymer-nanofiller interface. Therefore, the f-MoS2 is a potential candidate to overcome the brittleness of PS. In addition, this simple one-pot approach opens pathways for new developments of functionalized MoS2.
@article={003043446,author = {FIEL, Rodrigo; BARCELOS, Ingrid D.; GONÇALVES, Ricardo H.; SOARES, Mario R. S.; ROCHA, Gabriel; SILVA, Caio M. P.; MASTELARO, Valmor Roberto; LEITE, Edson R.},title={One-pot exfoliation and surface functionalization of MoS2: a potential nanofiller to overcome the brittleness of polystyrene (PS)},journal={Polymer},note={v. 233, p. 124187-1- 124187-8},year={2021}}