Effect of incorporating different types of Sentang tree waste particle on the thermal stability of Wood Polymer Composite (WPC)

This article presents the potential use of tree waste materials such as the leaves (L), branches (B) and trunks (T) of Azadirachta excelsa (Sentang) tree in the production of wood polymer composite (WPC). The WPC was fabricated from high-density polyethylene (HDPE) as bonding matrix, maleic anhydride (MA) as coupling agent, and Sentang tree waste particles (L, B and T) as filler, prepared using twin-screw extruder followed by injection moulding machine. The effects of incorporating these types of Sentang tree waste particle (at 35% and 45% particles loading by weight) on the thermal stability of WPC were reported. The chemical compositions of L, B and T were also determined and their influences on the thermal stability of WPC were discussed. The thermal behaviour was determined by using thermogravimetric analysis (TGA), whereas the chemical analysis using Technical Association of the Pulp and Paper Industry (TAPPI) methods. The addition of these tree waste particles as filler has increased the thermal stability of WPC compared to virgin HDPE (without any particle incorporation). The highest mass loss was experienced by virgin HDPE. It was also observed that chemical compositions of the particles played vital role in influencing the thermal stability of WPC.

ANALYSIS OF EFFECT OF TEMPERATURE CHANGE ON WOOD POLYMER COMPOSITE MATERIAL

In this work the research of new wood polymeric composite material as which filler timber industry waste in the form of sawdust, shaving, spill, lumpy waste and polyethyleneterephthalate, a research of its frost resistance by means of a method of a computer experiment is used is considered. A computer program has been developed to simulate the structure and physical properties of building blocks made of wood polymer composite material. The program allows you to set geometric and physical parameters of the building block and material components in the windows of the interface form in program code, as well as test conditions for cyclic heating and cooling to temperatures maximum possible during operation, and investigate the influence of parameters on the internal and surface destruction of the building block. The program is applicable for a wide range of concentrations of composite components, geometric parameters of the building block, various mechanical and thermocyclic tests. Influence of composition of wood polymer composite material on structure in thermocyclic tests is investigated. Dependencies of broken bonds on concentration of wood, cartogram of breaking bonds of wood polymer composite material with concentration of wood from 20 to 80% are obtained.

Mechanical Properties of Barley Straw/HDPE Composites Produced with Extrusion Process

This paper is devoted to the study of the technological process for the production of tape from polyethylene and wood-polymer composite by extrusion. At the first stage, the wood-polymer composite granulate was obtained on a co-rotating twin-screw extruder. The tape was made on a Rheomex 19/25 PolyLab OS single-screw extruder with a barrel length L/D = 25. The processing temperature of the wood-polymer composite was in the range of 145 ... 160°C. The tensile strength and elasticity modulus in tension, water absorption per day and density were investigated for the developed wood-polymer composite and polyethylene. It has been found out that for the developed wood-polymer composite, the strength and elastic modulus along the stretch direction increase by 11% and 6%, respectively. Orientation stretching has a significant effect on the physical and mechanical properties of wood-polymer composites.

Energy-saving technology for betulin extraction from birch bark waste

The paper presents experimental studies on the extraction of betulin from birch bark by one-stage extraction method in a flask with a reflux condenser and extraction in a Soxhlet apparatus. It is found that the highest betulin yield (up to 40 %) is achieved by extraction in a Soxhlet apparatus with periodic renewal of the extractant. The kinetic dependences obtained in the course of the research allows constructing an equilibrium dependence necessary to determine the rational number of phase contact stages when designing an industrial continuous extraction plant. On the basis of the studies carried out, a scheme of energy and resource-saving technology for extracting betulin from birch wood waste is proposed and a pilot plant is developed, which can be used to work out the modes of obtaining high-purity betulin. The absence of losses of organic extractants and the reuse of Florentine water determines the ecological purity of production. Refined birch bark can be used for the production of wood-polymer composite materials or as a fuel for generating thermal energy, which reflects the energy and resource-saving potential of this technology.

Environmental impacts of wooden, plastic, and wood-polymer composite pallet: a life cycle assessment approach

Purpose Waste recycling is one of the essential tools for the European Union’s transition towards a circular economy. One of the possibilities for recycling wood and plastic waste is to utilise it to produce composite product. This study analyses the environmental impacts of producing composite pallets made of wood and plastic waste from construction and demolition activities in Finland. It also compares these impacts with conventional wooden and plastic pallets made of virgin materials. Methods Two different life cycle assessment methods were used: attributional life cycle assessment and consequential life cycle assessment. In both of the life cycle assessment studies, 1000 trips were considered as the functional unit. Furthermore, end-of-life allocation formula such as 0:100 with a credit system had been used in this study. This study also used sensitivity analysis and normalisation calculation to determine the best performing pallet. Result and discussion In the attributional cradle-to-grave life cycle assessment, wood-polymer composite pallets had the lowest environmental impact in abiotic depletion potential (fossil), acidification potential, eutrophication potential, global warming potential (including biogenic carbon), global warming potential (including biogenic carbon) with indirect land-use change, and ozone depletion potential. In contrast, wooden pallets showed the lowest impact on global warming potential (excluding biogenic carbon). In the consequential life cycle assessment, wood-polymer composite pallets showed the best environmental impact in all impact categories. In both attributional and consequential life cycle assessments, plastic pallet had the maximum impact. The sensitivity analysis and normalisation calculation showed that wood-polymer composite pallets can be a better choice over plastic and wooden pallet. Conclusions The overall results of the pallets depends on the methodological approach of the LCA. However, it can be concluded that the wood-polymer composite pallet can be a better choice over the plastic pallet and, in most cases, over the wooden pallet. This study will be of use to the pallet industry and relevant stakeholders.

Experimental substantiation of method for increasing fire protection of wood composites with secondary polyethylene tereftalate

The expediency of involvement of the waste in the production of composite materials in the form of secondary polyethylene terephthalate is shown. The results of the experimental researches for justification of technological regimes of production of wood-polymer composite possessing the required thermal and water resistance are presented. The way of its flammability reduction by means of introduction of fire retardant into the binder composition is offered. In the course of experimental studies on increasing fire protection of wood composites with the addition of secondary polyethylene terephthalate, mathematical models reflecting the relationship of controllable factors (specific pressing time, the share of flame retardant addition) and operational indicators of the composite (strength, water and fire resistance) were obtained. Statistical processing of the experimental results confirmed the homogeneity of dispersions of all output values and the adequacy of the obtained mathematical models of the wood composite production process. It was shown that 17 % aluminochromophosphate introduced into the composite at a specific pressing time of 0,53 min/mm ensures a water-resistant composite with the required bending strength and weight loss during the fire action, corresponding to the flammability class G1. It is concluded that a further increase in the specific pressing time is inexpedient because the strength of the wood-polymer composite decreases due to destructive phenomena caused by prolonged heating of the wood component, and the release of a vapor-gas mixture from the aluminochromophosphate. The reduction to a minimum of — 4,8 % of the swelling of the composite in thickness for 2 hours at such a pressing duration was established. The recommendations for technological parameters of the production process, providing obtaining of composite with polyethylene terephthalate additive with the necessary physical and mechanical indicators and reduced loss of mass during combustion were developed.

Recycled Paper Additive for Wood-Polymer Composite: Preparation and Characterization

The recycling of paper and paperboard waste for obtaining powder cellulose has a positive impact on environmental and economic benefits due to its possibility to be applied in various fields of industry, including the fabrication of wood-polymer composite1,2. The extraction of cellulose from cellulose-containing wastes can be carried out by their mechanical disintegration with acid or alkali hydrolysis. In comparison with the known method3 the proposed method can be realized under more gentle conditions. For this aim, recycled de-inked waste paper was cut into small pieces (d < 5 mm) which were soaked in 0,05% hydrochloric solution at hydromodulus 1/20 (paper/water) for 2 hours at the intensive mechanical stirring for paper pieces disintegration. After soaking, the excessive water was pressed, and the disintegrated paper mass was dried, at first, at 60 °C for 16 hours and then at 120 °C for 2 hours. After drying, the paper mass was milled in a planetary mill for 15 minutes at a moderate rotation speed. The obtained cellulose particles were characterized by physicochemical properties. It was found, that obtained recycled paper particles (RPAP) had a similar contact angles with water compared to reference cellulose powder. However, polarity of RPAP was 20,5%, but of reference cellulose – 43,5%. RPAP could be characterized as more amorphous than cellulose because its crystallinity index was 61%, but reference cellulose powder – 81%. Using laser granulometry, it was found, that 99% of particles were less than 200 μm, and 90% of particles were less than 140 μm.

Evaluation of particle swarm optimization for strength determination of tropical wood polymer composite

A wood-polymer composite (WPCs) refers to wood-based components that are coupled with polymers to produce a composite material. Obtaining the best strength for the tropical WPCs is still a lack of research mainly for the tropical timber species and require a large consumption of time and cost. This paper highlighted the evaluation of particle swarm optimization (PSO) to assist in finding the optimal value of the composition of tropical WPCs to obtain the best strength that would offer a betterment in a quality product of WPCs. The findings demonstrate that PSO has been shown as a viable and efficient method for WPCs strength. The composition of Sentang, wood sawdust of 50%, HDPE of 49% and 1% coupling agent is demonstrated the best strength for the WPC. The employment of PSO as an assisted tool would give significant benefit to the manufacturer and researcher to determine the composition of material with less cost and time.