Electrospun nanocomposites from polystyrene loaded with cellulose nanowhiskers

Abstract

Composite microfibers from polystyrene and cellulose nanowhiskers were produced by electrospinning. The morphology of the microfibers was examined by using scanning and transmission electron microscopies. Surface porosity, unique ribbon-shapes, and the presence of twists along the fiber axis were observed in the composite microfibers. Thermomechanical properties of processed nanocomposites were studied by differential scanning calorimetry and dynamical mechanical analyses. The reinforcing effect of cellulose nanowhiskers was confirmed as the glassy modulus of electrospun microfibers increased with nanowhisker load. This effect is explained to be the result of mechanical percolation of cellulose nanowhiskers forming a stiff and continuous network held by hydrogen bonding. It is demonstrated that cellulose nanoparticles can be used effectively to reinforce hydrophobic matrices and to produce unique structural properties, enabling new functionalities and properties.

Orientation of cellulose nanocrystals in electrospun polymer fibres

“…Electrospun PVA fibres have been extensively studied to understand the effects of molecular weight [10], concentration [9] and the presence of additives on mechanical properties and thermal stability [11]. Polystyrene (PS), another commodity polymer, has also been electrospun into fibres [12]. PS exhibits different chemical, physical and functional attributes to PVA because of the presence of aromatic groups.…”

“…PS exhibits different chemical, physical and functional attributes to PVA because of the presence of aromatic groups. Rojas et al [12] have produced electrospun PS fibres reinforced with CNCs, observing unique ribbon shapes and the presence of twists along the axes of the fibres. The incorporation of CNCs was found to increase the glassy modulus of the fibres due to their mechanical percolation, forming a stiff and continuous network held together by hydrogen bonding in a hydrophobic matrix environment.…”

Bacterial cellulose nanowhiskers to enhance the properties of plastics and bioplastics of interest in food packaging

“…As shown in Figure 8, increasing the concentration of whiskers led to a significant decrease in the diameter of the achieved electrospun fibres, from an average diameter of 234.6 nm for the fibres obtained from 1 wt. electrospun fibres Rojas et al, 2009) with CNW concentrations up to 15 wt.-% and was related to an increase in the fibres conductivity when incorporating negatively charged CNW in the electrospinning solution. In addition to a decrease in the fibres' diameter, the BCNW incorporation gave rise to less beaded fibres.…”

“…Due to their potential as reinforcing agents for polymeric matrices, nanoclays (Kim et al, 2007;Yu & Cebe, 2009;Zhou et al, 2006) and cellulose nanowhiskers (CNW) Rojas et al, 2009;Zhou et al, 2011;Zoppe et al, 2009) have been incorporated into several polymers through electrospinning to produce reinforced hybrid fibres. In regard to other processing methods, when using hydrophobic polymers, the high hydrophilicity of CNW may lead to a lack of adhesion between the matrix and the CNW (Xiang et al, 2009).…”

“…Within the nanocomposites field, the incorporation of CNW into electrospun fibres has been mainly used to generate fibres with improved mechanical properties (Herrera et al, 2011;Huang et al, 2011;Rojas et al, 2009). …”