Hulya Kalaycioglu

The Manufacture of Particleboards using Sunflower Stalks (helianthus annuus l.) And Poplar Wood ( populus alba L.)

In this study, three-layer particleboards are produced from a mixture of sunflower stalks (Helianthus annuus L.) and poplar wood (Populus alba L.) at certain ratios utilizing urea-formaldehyde (UF) adhesives. Panels with a density of 0.7 g/cm 3are manufactured with the ratios of 25, 50, and 75 percent particles from sunflower stalks or poplar. For comparison, panels are solely manufactured with sunflower stalks and poplar wood. All panels are tested for physical properties (thickness swelling (TS) and water absorption (WA)) and mechanical properties (internal bond (IB), modulus of elasticity (MOE), modulus of rupture (MOR), and screw holding capacity (SHC)). Results show that all the panels provide properties required by the Turkish standards for general purpose-use particleboards. Furthermore, properties of the panels have improved with the rising percentage of poplar particles in the panels. The combination of sunflower stalks and poplar particles can be used at different ratios and the resulting panels can be utilized in indoor applications for general purposes such as furniture manufacturing. This result may prove that sunflower stalks can be an alternative raw material for the manufacture of particleboards.

Biological, physical and mechanical properties of particleboard manufactured from waste tea leaves

Abstract Environmental questions have arisen from the use of chemicals in wood or bio-based composite to stop biodeterioration. As a consequence, various environmentally friendly treatments or naturally durable plant species are now being evaluated. We believed the high phenolic extractive content of tea leaves, and their abundance as residual waste at tea producing factories warranted studies on the utilization of these wastes in particleboard manufacture. Waste tea leaves particleboard (WTLB) is expected to be more resistant against biological agents owing to high phenolic extractive content. Mass loss of WTLB, the edges of which had been sealed with an epoxy, was 3.5–8.6% and 6.0–12.1% for paraffin-added and non-added specimens, following degradation by Tyromyces palustris and Coriolus versicolor , respectively. The addition of paraffin to binder UF resin during the manufacturing of the board and sealing the edges of specimens before decay testing kept degradation to a minimum. In reference materials reported previously, WTLB proved resistant to decay-type fungi. Mass loss of WTLB after exposure to Formosan subterranean termite Coptotermes formosanus was around 16%. However, termite mortality levels and trends over the three weeks of termite attack suggest that phenolic extractives of tea leaf act as natural toxicants that gradually but steadily increase mortality particularly from the third week of exposure. Tested physical and mechanical properties of WTLB indicated that it performs as well as the general purpose boards designated in BS 5669.

Some of the properties of particleboard made from paulownia

The objective of this study was to determine some of the properties of experimental particleboard panels made from low-quality paulownia (Paulownia tomentosa). Chemical properties including holocellulose, cellulose, lignin contents, water solubility, and pH level of the wood were also analyzed. Three-layer experimental panels were manufactured with two density levels using urea–formaldehyde as a binder. Modulus of elasticity (MOE), modulus of rupture (MOR), internal bond strength (IB), screw-holding strength, thickness swelling, and surface roughness of the specimens were evaluated. Panels with densities of 0.65 g/cm3 and manufactured using a 7-min press time resulted in higher mechanical properties than those of made with densities of 0.55 g/cm3 and press times of 5 min. Based on the initial findings of this study, it appears that higher values of solubility and lignin content of the raw material contributed to better physical and mechanical properties of the experimental panels. All types of strength characteristics of the samples manufactured from underutilized low-quality paulownia wood met the minimum strength requirements of the European Standards for general uses.

Suitability of date palm (Phoenix dactyliferia) branches for particleboard production

The objective of this work was to evaluate the performance of particleboards manufactured from date palm (Phoenix dactyliferia) branches. Properties evaluated were bending strength (BS), internal bond (IB) and swelling in thickness (ST). Results showed that particleboards produced from date palm branches had the requirements of IB, BS and ST.

Tea mill waste fibers filled thermoplastic composites: the effects of plastic type and fiber loading

The objective of this study was to investigate the utilization of tea mill waste fibers (TMWF) in thermoplastic composites. For this purpose, two plastic types: polypropylene (PP) and high density polyethylene (HDPE), were used as thermoplastic material while TMWF was utilized as a lignocellulosic filler. HDPE or PP and up to 50% TMWF were compounded in the single screw extruder and extrudates were compression molded into thermoplastic composite panels. The effects of plastic type and fiber loading rate on mechanical (flexural, tensile, and impact properties), physical (water absorption and thickness swelling), thermal properties, and morphological of the produced composites were determined. Tensile modulus, flexural modulus, water absorption, and thickness swelling of the produced composites were increased with the rise of the TMWF amount in the thermoplastic matrix. On the other hand, TMWF increase in the thermoplastic matrix reduced the tensile strength, flexural strength, and impact strength of the produced composites. It should also be noted that both flexural strength and flexural modulus have satisfied the requirements of ASTM D 6662. In the case of thermal properties, addition of TMWF into the thermoplastic matrix did not change the initial degradation significantly. However, the char rate of the composites increased. It appears that tea mill waste fibers may have a potential usage as filler in the PP- and HDPE-based thermoplastic composites.

Technological properties of thermoplastic composites filled with fire retardant and tea mill waste fiber

In this study, physical, mechanical, thermal, fire and biological properties of thermoplastic composites filled with fire retardant and tea mill waste fiber were investigated. The composites produced with the extrusion method were accomplished by using tea mill waste fiber as lignocellulosic materials and high-density polyethylene and polypropylene as thermoplastic polymer. Aluminum trihydrate and zinc borate were incorporated with different contents into polymer matrix for improving fire properties of the composites, and their effects on technological properties of the composites were evaluated. Aluminum trihydrate had a positive effect on the tensile modulus of the composites whilst zinc borate had adverse effect on that of the composites. The strength properties of the composites slightly decreased with usage of fire retardant. In the light of obtained results, it was specified that use of fire retardants improved physical, biological, thermal and fire properties of tea mill waste fiber-filled thermoplastic composites.

Mechanical and Physical Properties of Cement-Bonded Perticleboard Made from Tea Residues and Hardboards

The residues of tea factory and waste hardboards are generally incinerated without utilizing their heat performances. The first objective of this study was to manufacture cement bonded particleboard using residues of tea factory (Camellia sinenses L.) and waste hardboards. The second objective was to evaluate modulus of rupture (MOR), modulus of elasticity (MOE), internal bonding strength (IB), water absorption (WA) and thickness swelling (TS) properties of the boards produced. The boards were produced at two density levels of 800 and 1200 kg/m3 and at five lignocellulosic mixture ratios of poplar chips/hardboards/tea residues (1/0/0; 1/1/0; 1/0/1; 0/1/0; 0/0/1, based on weigth). All the boards were produced at lignocellulosic material/cement ratio of 1:2.75 on a weight to weight basis. As cement curing accelerators, Al2(SO4)3 and Na2SiO3 were used at ratios of 1.5% and 3.5%, based on cement weight, respectively. The MOR values ranged from 0.8 to 10.99 MPa and MOE values ranged from 254 to 2979 MPa. The mean values of WA and TS after 24 h of water soaking of the cemen bonded particleboards ranged from 28% to 43.5% and 1.3% to 8.08%, respectively.

Predictive Models for Modulus of Rupture and Modulus of Elasticity of Particleboard Manufactured in Different Pressing Conditions

Abstract Determining the mechanical properties of particleboard has gained a great importance due to its increasing usage as a building material in recent years. This study aims to develop artificial neural network (ANN) and multiple linear regression (MLR) models for predicting modulus of rupture (MOR) and modulus of elasticity (MOE) of particleboard depending on different pressing temperature, pressing time, pressing pressure and resin type. Experimental results indicated that the increased pressing temperature, time and pressure in manufacturing process generally improved the mechanical properties of particleboard. It was also seen that ANN and MLR models were highly successful in predicting the MOR and MOE of particleboard under given conditions. On the other hand, a comparison between ANN and MLR revealed that the ANN was superior compared to the MLR in predicting the MOR and MOE. Finally, the findings of this study are expected to provide beneficial insights for practitioners to better understand usability of such composite materials for engineering applications and to better assess the effects of pressing conditions on the MOR and MOE of particleboard.