Nowadays, the emphasis is on increasing the durability of all products. For this reason, it is also advisable to look into extending the durability of paper products. The main reason for using flax pulp is that flax and cotton pulp are widely used for the production of banknotes due to their higher strength. This paper deals with flax pulp with the addition of nanocellulose, which should further enhance the mechanical properties of the pulp. The tensile strength, breaking length, and tensile energy absorption index were evaluated as the key mechanical properties. At the same time, the effect of the addition of nanocellulose, whether it was added to the pulp mass or applied to the later produced paper as a spray or coating, was tested in comparison to paper without the addition of nanocellulose. The best mechanical properties, i.e., tensile strength, were achieved for the highest addition of 5% of nanocellulose into the pulp, at 24.3 Nm∙g⁻¹, and for the coating application, at 28.7 Nm∙g⁻¹, compared to the flax pulp without the addition, where the tensile strength was 20.5 Nm∙g⁻¹. The results of this research are used for the assessment of nanocellulose as a natural compatible additive to enhance the strength properties of cellulose-based materials.

This research investigates the potential of secondary lavender biomass (Lavandula officinalis) as a raw material for paper production within the context of the circular economy and its practical applications. Lavender stems, a by-product of essential oil extraction, were processed using the nitrate–alkali pulping method. The chemical composition of the raw material was analysed according to TAPPI standards, and the resulting pulp was characterised in terms of its mechanical and physical properties, including tensile strength and air permeability. Lavender stems contained 29.43% cellulose and 24.10% lignin, indicating moderate delignification efficiency under the applied conditions. The pulp yield was 24.2% with a Kappa number of 15.9. Of the prepared sheets, the paper with a weight of 80 g·m⁻² showed the best mechanical properties, with a breaking length of 1.71 km and a tensile strength index of 16.76 N·m·g⁻¹. In addition, lavender-based paper demonstrated measurable repellent activity against Tineola bisselliella, reducing insect presence by 70% compared to control samples, as determined by controlled laboratory exposure tests. This bioactivity is attributed to residual volatile compounds such as linalool and linalyl acetate, originating from lavender biomass. Overall, lavender secondary biomass represents a promising non-wood fibre for the production of biodegradable, functional paper materials that combine structural integrity with natural repellent properties.

This research investigates the potential of secondary lavender biomass (Lavandula officinalis) as a raw material for paper production within the context of the circular economy and its practical applications. Lavender stems, a by-product of essential oil extraction, were processed using the nitrate-alkali pulping method. The chemical composition of the raw material was analysed according to TAPPI standards, and the resulting pulp was characterised in terms of its mechanical and physical properties, including tensile strength and air permeability. Lavender stems contained 29.43% cellulose and 24.10% lignin, indicating moderate delignification efficiency. The pulp yield was 24.2% with a Kappa number of 15.9. Of the prepared sheets, the paper with a weight of 80 g·m⁻² showed the best mechanical properties, with a breaking length of 1.71 km and a tensile strength index of 16.76 N·m·g⁻¹.In addition, lavender-based paper demonstrated a repellent effect against textile moths (Tineola bisselliella), reducing insect activity by approximately 70% compared to control samples. This bioactivity is attributed to residual volatile compounds such as linalool and linalyl-acetate. Overall, lavender secondary biomass represents a promising non-wood fibre for the production of bio-degradable, functional paper materials that combine structural integrity with natural repellent properties.

This research aims to efficiently convert biomass residues like wheat and rapeseed straw into potential cellulose-based nanomaterials using the iron( iii ) sodium tartrate solvent and assess their suitability for nanocellulose solutions based on the selected mechanical, physical, and optical properties of the paper. The nanocellulose solution from wheat straw achieved better general solvent properties. The burst index for kraft pulp was significantly increased from an initial 37.63 to 124.27 kPa after applying wheat nanocellulose solution, and to 121.03 kPa for rapeseed straw solution. Furthermore, the tensile index of the kraft pulp increases from 12.00 to 17.04 N m g ⁻¹ for the wheat solution and 14.39 N m g ⁻¹ for the rapeseed straw solution, which is comparable to industrial nanofibrils (14.04 N m g ⁻¹ ) and nanocrystals (15.88 N m g ⁻¹ ). This research confirms the potential of biomass residues as a valuable alternative raw material for producing a nanocellulose solution.

Barley straw represents an underutilized agricultural residue with potential as a supplementary source of papermaking fibers. This study compared nitrate–alkaline, soda, and peracetic-acid delignification processes for the preparation of pulp from barley straw and evaluated the resulting laboratory paper sheets. The raw material was characterized by a cellulose content of 35.84%, an acid-insoluble lignin content of 18.79%, and ash content of 7.65%. Seven pulping variants were assessed in terms of total yield, reject content, Schöpper–Riegler degree, and Kappa number, while the paper sheets were tested for tear index, burst index, ISO brightness, Cobb₆₀ water absorptiveness, and surface structure using optical microscopy. Total pulp yield ranged from 31.57% to 55.68%, and Kappa numbers varied from 13.50 to 47.86. Soda pulps had the highest Kappa numbers and the lowest brightness. Nitrate–alkaline treatments produced lower Kappa numbers than soda pulping but were generally accompanied by lower yields. Under the tested conditions, peracetic-acid delignification produced a pulp with a yield of 55.68%, a Kappa number of 13.50, an ISO brightness of 76.77%, a tear index of 6.26 mN·m²·g⁻¹, and a burst index of 0.67 kPa·m²·g⁻¹. Qualitative optical microscopy suggested a comparatively uniform fiber network. Among the evaluated variants, peracetic-acid delignification provided the most favorable combination of pulp yield, Kappa number, mechanical properties, and brightness; however, this finding is restricted to the specific treatment conditions applied in this study.