Poly(oxyethylene) and ramie whiskers based nanocomposites: influence of processing: extrusion and casting/evaporation

Abstract

Polymer nanocomposites were prepared from poly(oxyethylene) PEO as the matrix and high aspect ratio cellulose whiskers as the reinforcing phase. Nanocomposite films were obtained either by extrusion or by casting/evaporation process. Resulting films were characterized using microscopies, differential scanning calorimetry, thermogravimetry and mechanical and rheological analyses. A thermal stabilization of the modulus of the cast/evaporated nanocomposite films for temperatures higher than the PEO melting temperature was reported. This behavior was ascribed to the formation of a rigid cellulosic network within the matrix. The rheological characterization showed that nanocomposite films have the typical behavior of solid materials. For extruded films, the reinforcing effect of whiskers is dramatically reduced, suggesting the absence of a strong mechanical network or at least, the presence of a weak whiskers percolating network. Rheological, mechanical and microscopy studies were involved in order to explain this behavior.

An overview on properties and applications of poly(butylene adipate‐co‐terephthalate)–PBAT based composites

“…These composites are fabricated by three main methods: in-situ polymerization, melt mixing and solvent casting [38,60]. Each method has advantages and disadvantages [61]. In situ polymerization seems to be a promising method to fabricate composites because the natural fillers may be homogeneously dispersed into the unpolymerized solution containing the polymer monomers, leading to an efficient load transfer and consequently improve the ultimate mechanical properties of the composite [62].…”

PHBV/cellulose nanofibrils composites obtained by solution casting and electrospinning process

“…In this context, is possible to highlight nanocomposites such as poly(3-hydroxybutyrate)(PHB)/bacterial cellulose [7], polyvinyl acetate/sisal cellulose whiskers [8], natural rubber/cellulosic nanoparticles of sisal fibers [9], thermoplastic starch/cellulose nanofibrils from wheat straw [10], poly (oxyethylene)/ramie whiskers [11], and pea starch/cellulose whiskers from pea hull fiber [12].…”

Characterization of mechanical and morphological properties of cellulose reinforced polyamide 6 composites

“…The hydrophilic nature of nanocellulose (Gardner et al 2008;Peng et al 2013b) causes serious agglomeration during direct mixing with the polymer matrix, even in the process of mixing with polar polymer matrices. Cellulose nanocrystal suspensions were directly compounded with polar polymers of starch (Orts et al 2005) and poly(oxyethylene) (PEO) (Alloin et al 2011) using an extrusion process. Premixing of cellulose nanocrystal suspension with the polymer solutions was conducted prior to extrusion to increase the quality of dispersion and distribution.…”

“…Premixing of cellulose nanocrystal suspension with the polymer solutions was conducted prior to extrusion to increase the quality of dispersion and distribution. However, agglomeration or poor dispersion of the cellulose nanocrystals within polymer matrices was still observed (Orts et al 2005;Alloin et al 2011). Cellulose nanofibril suspensions were also directly added into apolar polypropylene (Yang and Gardner 2011) and polylactic acid (Iwatake et al 2008) during the melt compounding process.…”