One-pot exfoliation and surface functionalization of MoS2: A potential nanofiller to overcome the brittleness of polystyrene (PS)

Autor(es)

Fiel, Rodrigo ^[1] ; Barcelos, Ingrid D. ^[2] ; Goncalves, Ricardo H. ^[3] ; Soares, Mario R. S. ^[1] ; Rocha, Gabriel ^[1] ; Silva, Caio M. P. ^[1] ; Mastelaro, Valmor R. ^[4] ; Leite, Edson R. ^[5]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Dept Chem, Sao Carlos, SP - Brazil

^[2] Brazilian Ctr Res Energy & Mat CNPEM, Brazilian Synchrotron Light Lab LNLS, BR-13083970 Campinas, SP - Brazil

^[3] Univ Estadual Maringa, Dept Chem, Maringa, Parana - Brazil

^[4] Univ Sao Paulo, Sao Carlos Inst Phys, Sao Carlos, SP - Brazil

^[5] Brazilian Ctr Res Energy & Mat CNPEM, Brazilian Nanotechnol Natl Lab LNNano, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Polymer; v. 233, OCT 26 2021.
• Citações Web of Science: 0

Resumo

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 degrees C and 15 degrees 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. (AU)

• Processo FAPESP: 16/20493-0 - Esfoliação em etapa única e funcionalização covalente de nanofolhas de MoS2: desenvolvimento de novos materiais elastoméricos
• Beneficiário: Rodrigo de Souza Penha Fiel
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto