Volume 39, Issue 1

Trema orientalis and Trewia nudiflora are the fastest rotation trees (3–4 years’ rotation) in Bangladesh, and experimentally planted in social forestry in Gazipur district. Biorefinery is the most cited topic in research recent era in order to established circular bioeconomy. In established a biorefinery initiative, both species were fractionated into pulp, lignin and hemicellulose by formic acid (FA) treatment at atmospheric conditions. After alkaline peroxide bleaching of FA treated pulp, the yield was 47.0 % and 41.0 % with α-cellulose of 82.39 % and 81.61 %, and residual pentosan content of 9.26 % and 11.13 % for T. orientalis and T. nudiflora , respectively. The brightness of the pulps was 84.5 % and 85.0 %. Cold alkali extraction of the bleached pulp increased α-cellulose to 92.36 % and 91.29 % which was suitable for cellulose derivatives. Lignin was separated from the spent liquor by adding water. The FA lignin from hardwood replaced 20 % phenol in phenol-formaldehyde resin preparation without sacrifice of shear strength. The lignin separated FA liquor contains mainly pentose sugars, which was subsequently converted to furfural with a yield of 41.39 % and 41.72 % at 170 °C using 0.1 % H 2 SO 4 catalyst from T. orientalis and T. nudiflora , respectively.

Recycled paper has become increasingly used as a raw material in the paper industry. However, hornification limits its application. Herein, the effect of recycling on the mechanical properties and microstructure of khasi pine pulp was systematically studied. The mechanical properties deteriorated and water retention value decreased after recycling. X-ray diffraction and Fourier-transform infrared spectroscopy revealed that cellulose crystallinity increased and partial cocrystallization occurred on cellulose microfibrils. Through the analysis of the morphology of secondary fibers by FQA, the loss of fine fibers caused by each reuse was found. Using the filtration method to prepare the recycled paper reduced the loss of fine fibers and improved the mechanical properties, with the tensile strength of a sample prepared using a sand core filter unit for five cycles (8.37 MPa) being like that of a sample prepared using a paper machine after one cycle. The investigation of the internal structure of the paper showed that the retained fine fibers were bonded between the long fibers, promoting the bonding between the fibers. Fine fibers improve the curling and twisting of fibers to some extent, especially in the first three recycling cycles. The hornification phenomenon of recycled paper was studied from the viewpoint of the fiber components, which is important to promote the development and application prospect of recycled paper.

There is an ever-increasing demand for renewable, recyclable and biodegradable packaging solutions, from consumers, producers of goods, and producers of packaging materials. Closing the material loop and increasing recyclability of fiber-based package materials is one of the keys to move forward towards a more sustainable future. While the recyclability rates of fiber-based packaging are high, packaging boards with high wet-strength can pose problems due to problems with repulping. This manuscript investigated the possibilities to reduce the use of polyamide-epichlorohydrin resins (PAE) by supporting the process system with carboxy-methylated cellulose (CMC) through machine trials in mill scale production. The focus of the investigation was on the wet-strength of the board product and the repulpability value. The results given from the full-scale trial were positive, indicating a potential in using CMC while reducing the PAE addition. The results showed that wet tear strength and wet tensile strength of the board were maintained, while higher repulpability rates were given, encouraging better recyclability of the board material. This will be beneficial to the environment both with lower use of non-renewable chemicals and possibilities for higher degrees of recycling of the board products.

Due to the increasing demands of consumers from the food packaging, it enabled the improve of active packaging practices. Antimicrobial and antifungal coatings or films are an active packaging application. In such packaging materials, natural or synthetic antimicrobial material is added to the film or coating to help the packaging protect food. The use of biofilms produced from biopolymers in food packaging is more suitable than polymers with many damages such as PET, PE. Film production of many biopolymers such as cellulose derivatives, chitosan, PVA, starch PLA can be realized. Pelargonium graveolens plant is a natural source with strong antifungal and antimicrobial properties. For the reasons explained above, the experimental study aims to manufacture printable film with antimicrobial properties which is used in active packaging, using cellulose butyrate acetate and Pelargonium graveolens essential oil. For this purpose, cellulose butyrate acetate bio films, having variative ratios (0.1, 2.5, 5, 10 %) of Pelargonium graveolens oil, were produced with spin coating method. The transparency of prepared five different films were defined by UV–vis. spectroscopy. The antimicrobial properties of the produced films were measured against gram positive and negative bacteria. All produced biofilms were printed. The printability parameters of biofilms, (color, gloss) were determined. Consequently, cellulose butyrate acetate films loaded with Pelargonium graveolens oil were successfully produced. It is concluded that obtained all biofilms are with no color, transparent and printable with oil based inks. It was determined that the quantity Pelargonium graveolens oil raised in the biofilms had a strong inhibitory effect against gram positive and negative bacteria. With these features; produced films are considered to be suitable for active packaging applications.

Water plays an important role in the properties of cellulose. In materials design, the water uptake of cellulose has been traditionally seen as a drawback, since water reduces mechanical resistance of paper and cardboard, and at high hydration, cellulose-based products are disintegrated. However, recently, the hydration of cellulose has been considered as an advantage to design water-responsive soft actuators. In Nature, water is the fuel for several plant functions that involve motion, such as the seed release or the plant protection from high temperature and radiation. Inspired by these natural systems, cellulose-based actuators have been designed to display different movements (bending, twisting, curling) in response to water. Biopolymer structuration inducing anisotropy within the system allows the asymmetric expansion of layers, which results in macroscopic movement. This review gives an overview of the soft actuators triggered by the hydration/dehydration processes of cellulose. We present representative examples of water-triggered natural actuators, which have inspired researchers to design anisotropic cellulose-based materials that develop controlled movement in response to water.

This paper prepared the composite aerogel by adding graphene oxide (GO) and polypyrrole (PPy) to the cellulose nanofiber suspension. Then GO was reduced to RGO (reduced graphene oxide) with reducing agent, and CNFs/RGO/PPy composite aerogel with excellent conductivity was prepared. Scanning electron microscope (SEM) was adopted to analyze the structure and morphology of CNFs/RGO/PPy aerogel. Cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) were employed to analyze its electrochemical properties. The results showed that the best structure and electrochemical effect could be obtained when the ratio of CNFs/RGO/PPy was 6:2:3. At the current density of 0.25 mA cm −2 , CNFs/RGO/PPy composite aerogel had higher electrochemical performance, and the specific capacitance was 330 F g −1 . As an energy storage material, the composite has excellent potential in electrode materials.

Jabon ( Anthocephalus cadamba ) is a promising plant species with straight, visually pleasing trunks that can be harvested at a young age as a resource for pulp and paper production due to the rapid growth rate possessed. Therefore, this study aims to investigate the chemical composition and fiber biometry of 3, 6, and 9-year-old Jabon wood, determining their suitability as a pulp and paper raw material. Samples were collected from both stem and branch sections and analyzed according to the Tappi standard. Fiber cell maceration was conducted to enable the precise measurement of fiber dimensions and derivatives. The results showed high cellulose, holocellulose, and lignin content in Jabon wood, with low to moderate levels of extractives and ash. Additionally, the crystallinity index (CrI) increased with age, particularly from 3 to 9 years old. The branch of the plant, with Grade II fiber derivative quality, had lower CrI compared to the stem, while the inner stem showed a lesser value than the outer part. In conclusion, 3-year-old Jabon wood is a potential raw material for pulp and paper production.

In Chinese paintings, the marriage of rice paper and ink is the soul of this art. Ink possesses a highly distinctive “color” expressiveness. By employing ink, various shades of black and diverse color effects can be portrayed, making the image more rich, vibrant, and three-dimensional on a rice paper. However, when used in traditional ink wash painting, the flow and penetration of conventional ink is difficult to control, and its carbon black particles make it a challenge to achieve multiple transparent gradients. Considering the water solubility and two-dimensional nanostructure of graphene oxide (GO), the authors of this paper has developed and proposed the use of water-based GO ink for Chinese ink wash painting, aiming to endow it with new aesthetic forms and unique expressive potentials.