Using sonochemistry for the production of poly(vinyl alcohol)/MWCNT–vitamin B1 nanocomposites: exploration of morphology, thermal and mechanical properties

Abstract

The structure, crystallinity, and interfacial interactions as well as the thermal and tensile strength features of poly(vinyl alcohol) (PVA) reinforced with diverse concentrations of modified carboxylated multi-walled carbon nanotubes (MWCNT-CA) were studied. To prevent agglomeration and achieve a homogeneous distribution of MWCNTs onto the PVA matrix, initially, the surface of MWCNTs was covalently treated by inserting vitamin B₁ (B₁) and creating ester and amide groups via the ultrasonic distribution technique as an inexpensive, rapid, environmental, and impressive method. In the second step, diverse amounts of treated MWCNTs (3, 5 and 7 wt%) were exfoliated in the PVA matrix via ultrasonication and solution casting for the fabrication of PVA/B₁-MWCNT nanocomposite (NC) films. The characterization of the obtained PVA/B₁-MWCNT NCs and their thermal and mechanical performances are reported in this study. In comparison to other amounts of MWCNTs, the PVA/B₁-MWCNT NCs (7 wt%) showed better thermal property. Moreover, the presence of B₁-MWCNTs significantly improved the mechanical property when the loading amounts were only 1 and 5 wt% MWCNTs, which is optimal for the fabricated NCs. Excess MWCNTs had a great negative influence on the mechanical behavior of the PVA matrix.