Tuning of surface properties of poly(vinyl alcohol)/graphene oxide nanocomposites

Abstract

Surface properties are extremely important for materials applied in the biomedical areas such as poly(vinyl alcohol)-PVA. The precise control of the surface characteristics on these materials may adjust and expand its applications. Here, we present a new strategy to tune the surface properties of poly(vinyl alcohol)/graphene oxide (PVA/GO) films by manipulation of GO particles (amount and level of oxidation) and also by in situ reduction of GO. Adopting a different approach from the methods currently proposed, the reduction process of GO was carried out by exposing the PVA/GO films to hydrazine vapor to maintain the degree of particle dispersion. Raman spectroscopy, contact angle (surface energy), X-ray diffraction, and atomic force microscopy were used to evaluate the interaction between PVA and GO particles and also to characterize graphene polymer composites properties at the surface of the films. The results indicated that there is a strong interaction between the GO particles and polar PVA groups mainly at a very specific stoichiometric ratio. Consequently, the surface properties of the PVA/GO films may be tuned by altering the concentration of the particles, their level of oxidation as well as by the exposure to hydrazine vapor. The impact of these affirmations is extremely important for improving the suitability of PVA in applications such as biomaterial, membranes, packaging, and others that need a rigorous control of surface properties. POLYM. COMPOS., 00:000-000, 2017.

Composition dependence in surface properties of poly(lactic acid)/graphene/carbon nanotube composites

“…Moreover, the presence of graphene derivatives is known to affect the surface properties of polymer composites, particularly its wettability, e.g., the incorporation of small loadings of GNP are able to considerably change the surface wettability of PLA composite films [7] or when graphene oxide is used as filler for polyvinyl alcohol (PVA) to tune the surface properties of the nanocomposite [8]. Results of contact angle for carbon nanotubes (CNT) and different polymers, such as polypropylene (PP), polyethylene glycol (PEG), poly(methylmethacrylate) (PMMA), polyvinylidene fluoride (PVDF) are reported in the literature.…”

Novel improvement in processing of polymer nanocomposite based on 2D materials as fillers

“…As more oxygenated group are inserted, the intensity of the peak at 26 is decreased (comparing to the graphite XRD pattern) and the distance of the 002 plane is increased generating a peak around 10-11°. High level of graphite oxidation can turn almost all peak at 26° into ~10° [ 16]. The presence of oxygenated groups along graphitic structure turn it less stable than neat graphite resulting a weight loss observed in the region between 200 and 450°C ( Figure 2b) [17,18], while graphite is stable until near to 700°C.…”

Role of Graphene Oxide on the Mechanical Behaviour of Polycarbonate-Urethane/Graphene Oxide Composites

“…The interlayer spacing of 0.80 nm for GrO2 and 0.69 nm for GrO-4 was calculated using Bragg's law for plane (001) and shows the greater expansion between crystalline planes that occurred for the structure of the GrO-2 sample. This peak is typical for graphite oxide and comes from the expansion of the basal plane's distance that causes the Bragg angle displacement from 26.4° of the original graphite crystalline structure 18,19,34,37 . Higher displacement, better definition, and the higher distance of the basal planes were found at 2θ = 11° peak for GrO-2 than for GrO-4, strongly suggesting the GrO-2 possess a higher oxidisation level 37,39 .…”

“…GO is currently preferred for the manufacture of nanocomposites with various polymers such as polyethylene terephthalate (PET), poly (L-lactic acid) (PLLA), polyacrylamide (PAM), epoxy resin, poly (vinyl alcohol) (PVA), poly (methyl methacrylate) (PMMA), polypropylene (PP), poly(ethylene), and polyurethane elastomers such as poly(carbonate-urethane) (PCU) [17][18][19][20][21][22][23] . Common processing techniques, such as melt compounding, solution mixing, in-situ polymerisation, and latex mixing have been widely used for the fabrication of GO-polymer nanocomposites [24][25][26] .…”