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We present the results of a study of the dielectric and electrical properties of macroscopic reduced graphene oxide paper (RGOP) before and after 1 MeV electron irradiation with a low dose of 1⋅1016 cm−2. It was found that the Coulomb interaction affects the transport of charge carriers and causes their strong localization within graphene domains. The conductivity of the RGOP can be described by the charge carrier tunneling through a disordered graphene quantum dot array. It was shown that charge carrier localization length decreases from 5–8 nm to 1–2 nm after electron irradiation. Structural and electrical studies revealed that the irradiated sample demonstrates electrical conductivity higher than the initial one, despite the lower sp2-carbon fraction, the lower localization length, unchanged average size of graphene domains, and the higher defect states and functional groups content. The improvement in conductivity is also accompanied by an increase in the dielectric permittivity ɛ from 5 for the initial RGOP to 35 after electron irradiation. The data obtained indicate that disordered regions can affect the electrical properties of reduced graphene oxide.

The pulp and paper making industry is looking for new main raw material based on its physical, chemical and morphological characteristics. Currently in this industry, bagasse is the most useful raw material in pulp and paper industry. The objective of this study is to determine its suitability for pulping. Acacia auriculiformis is a fast-growing tree normally found in Indonesia and Australia. Acacia auriculiformis leaf contains of cellulose, hemi-cellulose and lignin. The range of lignin content in Acacia auriculiformis is 19%-20%. The hemi-cellulose and lignin contents was removed by soda-pulping process using different concentrations as followed; 3%, 5%, 10%, 15% and 20%. In order to determine the optimum pulping conditions for Acacia auriculiformis craft paper, several tests were conducted such as apparent density, tear test, tensile strength test and moisture absorption. It was found that the Acacia auriculiformis fibre treated with 3% sodium hydroxide (NaOH) solutions gave good tear test of the paper. For apparent density test, the best concentration of NaOH used for treating Acacia auriculiformis pulping is at 15%. From the study, the optimum concentration of NaOH in treating Acacia auriculiformis fibre is at 5% for best result in tensile strength. Hence, from the overall tests, 5% concentration of NaOH is the optimum value. From the findings, Acacia auriculiformis fibre has a potential to be used in paper making and food packaging industry.

The aim of this research was to manufacture composite panel that can be used as wall panel for earthquake resistantly building. First stage on wall panel production was done by preparing polypropylene plastic waste, coconut coir fiber, and waste sludge paper mill. The second stage was carried out by mixing polypropylene plastic waste with coconut coir fiber and sludge of paper mill waste. In this research, two mixing variations were carried out. First variation was done by mixing polypropylene plastic waste and coconut fiber in a ratio of 60:40 without adding sludge, while the other was done by mixing sludge, polypropylene plastic waste and coconut fiber with a ratio of 60:20:20. The mixing process was done using extruder and the drying process was done using hot press. Density, internal adhesion values, and thickness extension of resulted composite panels then was characterized. From two variations resulted wall panels were found that the wall panels with sludge addition has better density value of 0.9713 g/cm3 compare to composite panel without sludge addition where its density value of 1.093 g/cm3. In addition, the internal adhesive strength value of the wall panels without sludge addition of 0.59 N/mm2, whereas it improved to 0.61 N/mm2 on panel with sludge addition. Moreover, the thickness of the panel that was produced without sludge addition was 0.508 percent, while panel with sludge addition decreased to 0.104 percent.

Deforestation issues were increased dramatically every year especially in order for the production of paper. This was caused by the demand for making paper and furniture from wood sources. The supply of paper nowadays all depends on the wood. This experiment has been conducted to analyses the viability of magnetic pineapple leaves paper as a replacement for paper production and to analyses the morphology properties of pineapple leaves fiber. The introduction of filler in this research is to alter one or more paper properties such as texture, opacity, brightness, basis weight, dimensional stability, ink absorbency and overall printability. Commonly, most fillers are from clay, titanium dioxide or calcium carbonate. Thus, the ferrite magnet was used as the filler to ensure it has the same properties as the commercial filler. The pineapple leaves fiber then will be undertaking Scanning Electron Microscope (SEM) and Fourier-Transform Infrared Spectroscopy (FTIR) which was used for characterization. Through the characterization under Scanning Electron Microscope (SEM), the surface morphology of the magnetics pineapple leaves paper was changed due to the effect of the gamma radiation and by the degradation on the pineapple leaves fiber. Besides, for FTIR spectroscopy, the result indicated that pineapple leaves fiber was suitable for papermaking where the absorption peak is between 3400 – 2400 cm-1 and shows the presence of O-H and C-H bonds in polysaccharides for both magnetic and non-magnetic irradiated pineapple leaves paper. The magnetics pineapple leaves paper shows the good properties, as well as other commercial papers and this, will give many benefits to reduce the use of wood for making pulp and one of the efforts towards green technology and new invention on papermaking production.