Enhancing packaging board properties using micro- and nanofibers prepared from recycled board

In this study, cellulose microfibers and cellulose nanofibers (CNF) prepared from recycled boxboard pulp using a mechanical fine friction grinder were used as reinforcements in a board sheet. Micro- and nanofibers manufactured by mechanical grinding have typically broad particle size distribution, and they can contain both micro- and nano-sized fibrils. Deep eutectic solvent of choline chloride and urea was used as a non-hydrolytic pretreatment medium for the CNF, and reference CNF were used without any chemical pretreatment. The CNF were ground using three grinding levels (grinding time) and their dosage in the board varied from 2 to 6 wt%. The results indicate that the board properties could be tailored to obtain a balance between the processability and quality of the products by adjusting the amount of CNF that was added (2–6 wt%). A preliminary cost assessment indicated that the most economical way to enhance the board strength properties was to add around 4% of CNF with a moderate grinding level (i.e., grinding energy of 3–4 kWh/kg). Overall, the strength properties of the manufactured board sheets improved by several dozen percentages when CNF was used as the reinforcement.

Optimising the process for production of high performance bagasse-based composites from rice bran-UF adhesive system

Purpose – The purpose of this paper is to prepare high-performance agro-based composites from the non-toxic rice bran-urea-formaldehyde (RB-UF) adhesive system. Investigations have continued for production high performance agro-based composites using environmentally acceptable approaches. The utilisation of such system with the available used local agro-based wood products (sugar-cane bagasse, SCB) adds economic value and helps reducing the environmental impact of commercial urea-formaldehyde (UF) adhesive, and most importantly, provides a potentially inexpensive alternative to the existing commercial artificial wood-panel mills. Design/methodology/approach – Optimising the process for incorporating the RB in UF, as wood adhesive for binding the bagasse fibres, was carried out, by partially replacing commercial UF by denaturalised RB in slurry (wet) and dry form or through synthesis of UF. The denaturalisation of RB was carried out at different pHs (10-11) and at temperature 60°C for two hours. While incorporating the RB during synthesis of UF, it was carried out according to the method reported elsewhere. The formulation of adhesive components, pH value of the denaturalisation stage and the process of incorporating the RB were optimised. Assessment of the role of RB adhesive was specified from its free-formaldehyde (HCHO) content, as well as the properties (mechanical and physical properties) of the produced composites of bagasse particle board type, in comparison with the environmental impact of commercial thermosetting resin (UF). Findings – The promising adhesive system exhibits improvement in the environmental performance (as E1 type) over a commercially UF adhesive (as E2 type), besides providing boards fulfill the requirements of grade H-3 (according to ANSI A208.1 (NPA1993). This adhesive system was resulted from replacing 30 per cent of UF by denalturalised RB (at pH 10) in slurry form. Where, its reduction in free-HCHO reached 53 per cent, as well as modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB) and TS of the produced boards were approximately 24.2 N/mm2, approximately 3753 N/mm2, approximately 0.84 N/mm2 and approximately 11.4 per cent, respectively. Research limitations/implications – The eco-adhesive with relatively high percentage of low-cost commercial UF (70 per cent) and 30 per cent RB, as oil production by-product, in slurry form provides good board strength and is environmentally friendly compared to SCB-based composite properties, with that produced from commercial UF. The mechanical (MOR, MOE and IB) and water-resistance properties of the produced composite comply with the standard values. Practical implications – The approach provided low HCHO-free UF adhesive with good comparative board strength and water resistance and reasonable working life. Replacing 30 per cent of UF by RB in slurry form and denaturalised at pH 10 is considered a promising inexpensive alternate adhesive (as E1) in the wood industry based on SCB wastes. Social implications – Incorporating the RB by-product of oil production to commercial UF will be beneficial for saving the health of wood co-workers and motivating the wood mill to export its wood products. Originality/value – It provided a potentially simple way to improve both the utilisation of commercial UF and SCB as industrial substrates for particle-board production. This will benefit farmers, local wood mills in Upper Egypt, significantly. Meanwhile, incorporating low percentage of RB, as oil-mill by-products, is promising to partly replace UF resin in the wood industry, minimising formaldehyde emission or toxic gasses during board formation.

Study on the Strengthening of Kraft Liner Board by the Application of Series WEC Cleaner Papermaking Chemicals

The improvement of Kraft Liner board strength, including burst index, ring crush index , inter-layer binding strength and folding endurance was investigated. The performance of several WEC paper chemicals were compared to select the optimum one and the most appropriate level. It was found that: (1) with respect to bottom liner board pulp, the optimum furnish was experiment G-3 with the dosage of 0.3% WEC03S + 0.2% WEC02 , while ring crush index being increased by 47.6% , folding endurance by 50.0% and burst index by 20.7%. (2) in terms of three layers composite structure of linerboard, the optimum furnish was experiment E-4 with the dosage of 0.3% WEC03S + 0.1% WEC02 +0.04% WEC02A for cover layer , that of 0.3% WEC02 + 0.03% WEC02A for bottom layer , and that of 0.03% WEC02A for core layer.

A Study of Effect Factors on Sodium Silicate Based Expanded Perlite Insulation Board Strength

Because of low strength, the expanded perlite insulation boards application in building energy saving is restricted. This paper discuss change rules of the expanded perlite insulation board apparent density and mechanical strength with adjusting the amount of sodium silicate, pressing pressure, heating system. It turned out that good thermal insulation performance and high strength expansion perlite insulation board is prepared by mass ratio of 2.5:1 of 30% of the content of solid sodium silicate solution to expanded perlite, 0.38MPa of pressing pressure and 105°C condition of heating temperature.

Recycled Old Corrugated Container Fibers for Wood-Fiber Cement Sheets

Recycled pulp of old corrugated containers (OCCs) was studied as a possible fiber source for wood-fiber cement (WFC) sheets. This industry currently largely relies on kraft pulp, an expensive fiber source. Thus, WFC sheets were made using less costly OCC fibers utilizing various types of treatments including fiber fractionation (FF) and refining to 500 and 400 Canadian Standard Freeness (CSF) to determine the effect of these treatments on the sheets strength. Unprocessed virgin kraft fiber of radiata pine (Pinus radiata) was used as control for comparison purposes. The unprocessed OCC pulp furnish yielded an initial freeness of 635 CSF; after fractionating, however, it was increased to 754 CSF. OCC pulp presented a kappa number of 47, compared to 23.7 for P. radiata. Fractionating OCC pulp was effective in raising the range of long fibers in the stock from 68 percent to 85 percent, before and after fractionating, respectively. Results from WFC sheets made in laboratory showed that there was no significant difference in board strength among boards made with unprocessed OCC fibers, fractionated and refined OCC, and P. radiata fibers. However, sheet strength decreased when refined OCC fibers were used. The results suggest that OCC fibers can produce WFC sheets with desirable characteristics compared to those of unrefined virgin kraft fiber of P. radiata.

The Effect of Governance on Credit Decisions and Perceptions of Reporting Reliability

ABSTRACT: We conduct an experiment to examine how lending decisions are affected by lender perceptions of reporting and governance quality. We perform a set of experiments to determine whether lenders are sensitive to the quality of governance as measured by board composition along multiple dimensions, whether their perceptions of reporting reliability are a function of the strength of the board, and whether their lending decisions are then affected by their perceptions of reporting reliability. Study participants are a group of 62 professional lenders from Singapore, with at least three years of professional credit analysis and lending experience. We find that lenders are primarily sensitive to financial condition and the perceived reliability of financial reporting. While we also find that lenders are sensitive to board strength, further tests suggest lenders appear particularly sensitive to board strength only for relatively high-performing firms. We also find that the perceived reliability of the financial reports does not appear to be affected by board strength or by the applicant’s financial condition. The paper discusses implications for policy making, practice, and research.