COMPARATIVE PROPERTIES OF AGROFIBER BASED PARTICLEBOARDS USING NEWLY DEVELOPED BONDING MATERIALS Zeinab A. Osman, Ph.D Department of Cellulose Chemistry and Technology Institute for Technological Research National Center for Research 4/6/2019

Contents Brief introduction Objectives of the study Experimental, adhesives formulation and Particleboard preparation. Preparation of cost effective adhesives, labs and semi industrial trials Results Conclusion 4/6/2019

Introduction 1- To save forests. Surface area 2,558km 2- To provide wood alternatives (renewable resources) to replace the traditional solid wood. 3- to meet the demand on wood products. 4/6/2019

Objectives The objectives of this work are: To provide technical information on the manufacture of agro fiber particleboard and to develop new bonding materials of high performance and of low cost to compensate for the lighter weight of these fibers which necessitate the use of high level of resin loadings. It also aimed at evolving the optimum conditions and process technology for the utilization of these fibers without any further treatment (chemical, mechanical) in order to reduce the overall cost of production. 4/6/2019

Experimental Adhesives formulations Solutions of the Pine tannins with two different concentrations (35% and 47%) and two different pH values (5 and 9 respectively) were used in mixtures with different hardeners such as: 1. Tannins modified – 8% paraformaldehyde. 2. Tannins – 5% paraformaldehyde. 3. Tannins – 5% urea and 5 % paraformaldehyde. The PUF resins were obtained from Dynea Company, Austria and phenol formaldehyde.PF which was synthesized in laboratory according to the procedures outlined in the Advanced Wood Adhesives Technology (Pizzi, 1994) and a commercial PMDl were used to formulate different adhesive systems. 4/6/2019

Particleboard preparation One layer laboratory particleboards of 350 X 310 X 16 mm dimensions were produced from different fibers by using previously mentioned formulations. Different levels of resins loadings and different board densities comprised between 550 and 670kg/m3 were used. A pressing cycle with an initial maximum pressure of 61 bars and a pressing time of 5.30 to 7.30 minutes was used. Agricultural wastes and low quality fiber : - The Bagasse - The hemp Eucalyptus 4/6/2019

Manufacure of particleboard : Results and Discussion Panel from the Bagasse Glue formulations Internal bond (MPa) V100 Thickness swelling (%) Density (Kg/m3) 18% pine tannin 8% paraformaldehyde 0.34 0.11 34 699 11% pine tannin + 3%PMDI 5% paraformaldehyde 0.23 0.00 50 639 11%PUF+3%PMDI + 1% pine tannin+ 0.1paraformaldehyde 0.24 40 629 PUF (15%) 0.31 0.12 26 638 13%PUF+ 2%PMDI (15%) 0.21 36 PUF 0.46 0.14 54 842 pH 4/6/2019

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Manufacure of particleboard : Results and Discussion Panels from Eucalyptus Glue formulation Ref = 0.35 Internal bond (MPa) V100 Thickness swelling (%) Density (Kg/m3) PMDI (8%) 1.04 0.19 31 596 14 pine tannin+8% paraformaldehyde 0.75 0.11 45 663 14 pine tannin+ 5% paraformaldehyde +5% urea 0.27 0.00 672 10% pine tannin+3% PMDI+5% paraformaldehyde 0.78 0.15 40 614 7%PF +3% PMDI+1% pine tannin 0.1 paraformaldehyde 0.44 0.12 44 610 PF + 10% pine tannin 0.25 7%PUF +3% PMDI+ 1% pine tannin 0.47 53 608 PUF alone (15%) 0.10 37 810 pH pH 4/6/2019

Conclusion - The Eucalyptus and the bagasse having both a lower pH produced inferior quality panels which did break during the tests. This only applied when resins of lower pH were used or when an acid or neural material such as the urea, polymeric diphenylmethane diisocyanate (PMDI) was mixed with the tannins, PF and the PUF. - Satisfactory performance of tannin-based adhesives with the Hemp, the Bagasse and  the Eucalyptus at relatively high pH. - Panels from Hemp (without depithing), can be used for furniture (EN 312 – 3) - When we increase the density of panel made from Bagasse we obtain panel suitable for furniture and internal uses - The light weight of agricultural wastes is the necessity of utilizing high percentage of the adhesives. 4/6/2019

Formulation of Low- cost adhesives Why ? : 1 – Light weight of agricultural wastes Bagasse 2 – Interest of the European industry, Dynea Company 4/6/2019

Formulation of Low- cost adhesives : Materials and methods Formulations Commercial PUF resin with 46 30 25 20 15 8 + Low percent of PMDI (10, 8, 5%) (expensive ) % of Urea cheap Addition of urea (heating) (50°C for t 30 min). Evaluation of the particleboard 4/6/2019

Formulation of Low- cost adhesives Values of V100 Thickness swelling 4/6/2019

Semi Industrial trials Formulations has been chosen for their excellence and cost effective: PUF + 15 % of urea PUF + 20% of urea reference value for V100 = 0.15 Glue formulations V20 (MPa) V100 Thickness swelling (%) Density(kg/m3) PUF 0.22 0.10 16 646 + 10% PMDI 0.73 0.25 727 + 15% urea + 10%PMDI 0.57 0.19 18 714 + 20% urea 0.52 0.16 17 707 Glue percent = 13.5% 4/6/2019

Evaluation of the particleboard from agricultural wastes and cost effective adhesives Low-cost glue from PUF + 15% urea + 5% PMDI (15%) Types of agric. wastes Internal bond (MPa) V100 Thickness swelling (%) Density Pressing time (Min.) Cotton stalks 0.41 0.14 34 713 5.30 Bagasse 0.34 0.13 21 708 7.30 Groundnut shells 0.00 710 Maize straws 0.10 717 Internal bond value > standard value(0.24MPa) For panel for general utilisation 4/6/2019

General Conclusion 1 - Cost effective formulations have been invented from PUF and PMDI and it can be used for the production of panels with exterior qualities. The lab experience has been transferred to the industry with great successful. 2 - the possibility of using agricultural wastes in the panels manufacture has been proven, the process still to be optimized. 4/6/2019

Acknowledgements National Center of Research and the French embassy sponsorship of this research are very acknowledged. Dynea company, Austria for the provision of the PUF 4/6/2019

Thanks for your attention 4/6/2019