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Molecular dynamics (MD) simulation is used to study effects from moisture at cellulose nanofibril (CNF)–graphene oxide (GO) interfaces adhering in the wet state.

With respect to the importance of energy consumption reduction in industrial plants, an attempt has been made to specify the most important parameters affecting energy consumption of plastic injection molding process as one of the most energy intensive processes in plastics industry. In this regard, the specific energy consumption of six hydraulic injection molding machines and the profile of their energy consumption over one cycle of injection molding process were measured to assess the effect of different machine related and process related parameters on energy consumption and realize energy saving opportunities in the injection molding process. Results showed that among all quantitative parameters, throughput and total cycle time, which are process related parameters, have the most important impact on the specific energy consumption of the process. Whereas, the most important effect of machine related parameters were found to be on the peak power of energy consumption, which gives an insight to industrial plants how to reduce the maximum electrical demand of the plant. In addition, it was proved that each hydraulic injection molding machine has a unique profile of energy consumption depending on the design of the machine and process, and then according to these profiles, three types of process designs were identified.

Nanocomposites from native cellulose with low 2D nanoplatelet content are of interest as sustainable materials combining functional and structural performance. Cellulose nanofibril–graphene oxide (CNF–GO) nanocomposite films are prepared by a physical mixing–drying method, with a focus on low GO content, the use of very large GO platelets (2–45 μm) and nanostructural characterization using synchrotron X-ray source for WAXS and SAXS. These nanocomposites can be used as transparent coatings, strong films or membranes, as gas barriers or in laminated form. CNF nanofibrils with random in-plane orientation, form a continuous non-porous matrix with GO platelets oriented in-plane. GO reinforcement mechanisms in CNF are investigated, and relationships between nanostructure and suspension rheology, mechanical properties, optical transmittance and oxygen barrier properties are investigated as a function of GO content. A much higher modulus reinforcement efficiency is observed than in previous polymer–GO studies. The absolute values for modulus and ultimate strength are as high as 17 GPa and 250 MPa at a GO content as small as 0.07 vol%. The remarkable reinforcement efficiency is due to improved organization of the CNF matrix; and this GO-induced mechanism is of general interest for nanostructural tailoring of CNF-2D nanoplatelet composites.

In this work, a facile and scalable method to produce cellulose based flexible electrodes is introduced. Composite paper electrodes from recycled paper pulp and graphene oxide (GO) were fabricated by solvent casting at room temperature. Electrical conductivity and surface chemistry of the nanocomposite samples were tuned by chemical reduction of GO. Contact angle measurements showed a change in water droplet angle from 0° to 89° depending on the GO content and degree of reduction. Electrical measurements depicted high electrical conductivity with an ideal Ohmic behavior for the composite paper electrodes. Sheet resistance of the sample containing 4 wt% of reduced GO (rGO) was 1.649 × 103 Ω/□ which is 5 orders of magnitude higher than paper pulp. The obtained sheet resistance for the sample with 16 wt% rGO was remarkably high for cellulose based conductive electrode compared with previously reported data. Moreover, the sample containing only 0.5 wt% of rGO showed 40% higher modulus than the neat recycled paper in tension. The resultant nanocomposite can be introduced as a highly conductive and low cost flexible electrode.

In this research, an attempt was made to stabilize reduced graphene oxide (rGO) in all pH ranges, incorporating both chitosan (CS) and hydroxyethyl cellulose (HEC) to make a proper drug carrier with suitable stability and drug release behaviour. The stability of rGO-CS-HEC nanohybrid was assessed using field emission scanning electron microscopy (FE-SEM), ultraviolet-visible spectroscopy (UV-Vis) and Zeta potential measurements. Results depicted that the novel synthesized nanohybrid was stable in all pH ranges, due to the utilization of HEC, while without incorporation of this material, the rGO-CS nanohybrid aggregated at neutral and alkaline media, due to the ionic nature of chitosan. In addition, drug loading and release behaviour of folic acid (FA), as a model drug, was investigated to assess the role of chitosan on the release behaviour of FA from the rGO-CS-HEC nanohybrid in comparison with rGO-HEC and rGO-CS nanohybrids. It was proved that the resultant nanohybrid could release nearly 27% more FA than the rGO-HEC nanohybrid and only 9% lower than the rGO-CS nanohybrid during 120h. Moreover, the biocompatibility of the resultant nanohybrid was also checked to introduce the novel rGO-CS-HEC nanohybrid as a suitable candidate for drug delivery application.

Stabilization of graphene oxide (GO) in physiological solution is performed using hydroxyethyl cellulose (HEC) to make the resultant nanohybrid suitable for targeted drug delivery purposes. Short and long term stability of GO suspensions with different ionic strengths were assessed using ultraviolet–visible spectroscopy (UV–vis), atomic force microscopy (AFM) and zeta potential measurements. Results depicted that HEC effectively stabilized GO in electrolyte solutions and the mechanism of stabilization appeares to be depended on HEC content. Drug loading and release behavior of folic acid (FA) as a model drug, from GO–HEC nanohybrid were studied to assess its application in drug delivery systems. Results showed the nanohybrid could be highly loaded by folic acid. Moreover, HEC content in the nanohybrid played an important role in final application to make it applicable either as a carrier for controllable drug release or as a folate-targeted drug carrier. In addition, according to cytotoxicity results, the nanohybrid showed good biocompatibility which indeed confirms its potential application as a drug carrier.