Pine Wood Fiber Research Articles

Thermal Insulation Panels with Bio-Based Adhesives

Environment friendly insulation panels were manufactured and tested made of pine wood fibers and glued with a bio-based adhesive, called dextran. The aim of this work was to determine relevant technical properties of panels fabricated with this new glue type. In the panels, the ratio of dry glue content was varied from 30% to 60% with 10% steps which runs served as comparison basis. The density of the insulation panels was set to 70 kg/m3, 100 kg/m3 and 125 kg/m3. Beside their thermal conductivity, the compression strength, the bonding strength, and the wetting angle of the adhesive were measured. With the variation of panel densities, the thermal conductivity is in a narrow range of 0.039 to 0.042 W/mK. The resistance to compression at 10% strain was measured to be 0.3 MPa, 0.35 MPa and 0.4 MPa in the panels with 70 kg/m3, 100 kg/m3 and 125 kg/m3, respectively. The wetting angle of the adhesives seemed to correlate only weakly with the bonding strength, and the glue`s wetting ability diminished with the increase of the glue content. The results seem to be competitive if compared with the traditionally used glass and rockwool, and foam insulation materials.

Experimental and numerical investigation of damage and mechanical property retention by bio-composite plastic made with flax or pinewood fiber and aged by exposure to ultraviolet light

The objective of this study was to compare two types of natural short fibers, one lignin-rich and one lignin-poor, as reinforcing filler of bio-composite plastic in accelerated aging experiments. Short natural-fiber-reinforced plastic composites of flax fiber or pinewood fiber (30 % by weight) were injected and then exposed to ultraviolet (UV) light with and without moisture for up to 1440 h. Color, roughness, and mechanical properties were then evaluated using colorimetry, confocal laser imaging, tensile tests, and drop-weight tests. Damage to the bio-composites was monitored using the acoustic emission technique during tensile testing. The response during impact tests was simulated using the finite element method. Results showed that flax-fiber-reinforced polypropylene exhibited superior properties before aging, but experienced greater loss of these properties after aging, particularly under moist conditions. The numerical model was found to be in good agreement with the experimental results.

Effects of Medium Density Fiberboards (MDF) Recycling Methods on Fiber Dimensions and Some Reconstructed Board Properties

In this study, different methods, including acid hydrolysis (phosphoric and formic acid), thermohydrolysis, and microwave methods were tested for recycling of fiberboards made of 100 % beech and 70 % beech + 30 % pine wood fibers, which are widely sold in the market. The impacts of the using methods on the fibers were investigated with the help of a device that determines the fiber dimensions according to optical principles. In a laboratory setting, test boards were constructed using recycled fibers, and the changes in certain physical and mechanical qualities were studied. As a result, it was determined that recycled fibers obtained from microwave and thermo-hydrolysis fibers could be effectively used in fiberboard production. However, the proportion of fibers, longer than 1.24 mm, was decreased by about 30 % with the phosphoric acid method for MDF samples composed of 100 % beech fiber. The fiberboards could not be obtained from fibers recycled through acid hydrolysis except for phosphoric acid method with 100 % beech fibers.

Effects of Mixes of Peat with Different Rates of Spruce, Pine Fibers, or Perlite on the Growth of Blueberry Saplings

Investigations of substrates for growing plant saplings is the basis for the search for new components. Currently, large numbers of saplings are grown for blueberry plantations. Studies on the use of various organic and inorganic components in substrates is relevant in order to reduce the amount of excavated peat. The goal of this study was to analyze the effects of mixes of peat with different rates of spruce, pine fibers and perlite on the growth of blueberry saplings. To define the suitability of substrates, plant vigor assessments of the cultivar ‘Duke’, including plant height and leaf weight, as well as the chlorophyll fluorescence, content of extractable macronutrients and organic carbon in leaves, were investigated. The best effect on the growth of blueberry saplings, the optimal content of macronutrients in the leaves, was shown for substrates in which a part of the peat was replaced by 15–45% v/v of pine wood fiber and by 15–30% v/v of spruce wood fiber. Pine bark fiber in the mix should not exceed 30% v/v. The addition of spruce bark fibers in the different rates had a negative effect on the vegetative growth of the saplings. The quantity of peat in the substrates can also be significantly reduced by adding 15–45% v/v of perlite. These results confirm that pine and spruce fibers or perlite in substrates for blueberry sapling growing could reduce the demand for peat and should significantly contribute to the preservation of unique wetland ecosystems.

Nanostructural Changes Correlated to Decay Resistance of Chemically Modified Wood Fibers

Reactive chemical modifications have been shown to impart decay resistance to wood. These modifications change hydroxyl availability, water uptake, surface energy, and the nanostructure of wood. Because fungal action occurs on the micro and nano scale, further investigation into the nanostructure may lead to better strategies to prevent fungal decay. The aim of this article is to introduce our findings using small angle neutron scattering (SANS) to probe the effects of chemical modifications on the nanostructure of wood fibers. Southern pine wood fiber samples were chemically modified to various weight percentage gains (WPG) using propylene oxide (PO), butylene oxide (BO), or acetic anhydride (AA). After modification, the samples were water leached for two weeks to remove any unreacted reagents, homopolymers or by-products and then the equilibrium moisture content (EMC) was determined. Laboratory soil-block-decay evaluations against the brown rot fungus Gloeophyllum trabeum were performed to determine weight loss and decay resistance of the modifications. To assist in understanding the mechanism behind fungal decay resistance, SANS was used to study samples that were fully immersed in deuterium oxide (D2O). These measurements revealed that modifying the fibers led to differences in the swollen wood nanostructure compared to unmodified wood fibers. Moreover, the modifications led to differences in the nanoscale features observed in samples that were exposed to brown rot fungal attack compared to unmodified wood fibers and solid wood blocks modified with alkylene oxides.

Fundamental Investigation of Biomass Interaction for Green Composites: Experiments and Molecular Dynamics Simulations

AbstractUnderstanding biomass interaction is critical for bottom‐up design of novel biocomposites and existing manufacturing processes. In this study, interactions between bioadhesives (lignin, carbohydrates, or proteins) and fibers (cellulosic fiber or wood fiber) are elucidated via experimental bonding strength tests and molecular dynamics (MD) simulations. Experimental results reveal a good, nearly linear correlation between the composite's density and tensile strength, a finding which has rarely been reported previously. Adhesives are compared to one another: soy protein isolate is found to be the best for pinewood fiber, while apple pectin and soy protein isolate are the best for α‐cellulose fiber. It is further shown that the fiber type plays an important role in defining the composite strength. In agreement with experiments, the MD simulations at nanoscale predict a linear strength to density correlation; this is driven by the hydrogen bond (H‐bond) content in the composite. The H‐bond content is also found to determine the varied performances of different adhesives.

MECHANICAL AND PHYSICAL PROPERTIES OF WOOD/POLYETHYLENE COMPOSITE REINFORCED WITH TIO2 NANOPARTICLES

Wood plastic composite was fabricated using high density polyethylene and pine wood fiber. The effect of addition of TiO2 nanoparticles at different weight fractions (0%, 1%, 3%, and 5%) on some properties of the composite was examined. The experimental composites were tested for bending strength, tensile strength, Izod impact strength, thickness swelling, and contact angle. Field emission scanning electron microscopy was also investigated to study the distribution of TiO2 nanoparticles in the composites. The results showed that using TiO2 nanoparticles as a reinforcing agent in wood plastic composites resulted in an increase in the tensile and bending strengths and a decrease the thickness swelling of the composites. The effect of TiO2 nanoparticles on the Izod impact strength of composites was not significant. The results also showed that the contact angle of wood plastic composites was improved by using TiO2 nanoparticles.

Evaluating Peat Substrates Amended with Pine Wood Fiber for Nitrogen Immobilization and Effects on Plant Performance with Container-grown Petunia

Pine (Pinus sp.) wood products have potential to immobilize fertilizer nitrogen (N) and influence plant growth when used in soilless substrates for the production of containerized floriculture crops. Peat substrate was amended with (by volume) 30% pine wood fiber (peat:fiber) during a production phase with fertigation and a simulated consumer retail phase with clear-water irrigation using container-grown ‘Supertunia Vista Bubblegum’ petunia (Petunia ×hybrida). The objective was to evaluate substrate effects on substrate and plant tissue nutrient level and plant growth, with an emphasis on evaluating N immobilization from wood product amendments. Substrates consisting of peat amended with hammer-milled pine wood (peat:wood) or coconut (Cocos nucifera) coir (peat:coir) were used for comparison, and a 100% peat substrate (peat) served as a control. In Expt. 1, amending peat with pine wood fiber had no effect on leaf SPAD chlorophyll index, shoot growth, plant height and width, substrate N, or percent shoot tissue N at the end-of-production. In Expt. 2, plants grown in peat:fiber had reduced flower number, plant height and width, and shoot growth compared with plants grown in the 100% peat control. However, petunia grown in peat:fiber substrates maintained dark-green foliage with high leaf SPAD chlorophyll index values (≥44.4) and ≥45 flowers/plant, and therefore were considered marketable plants. During the production phase in both Expts. 1 and 2, N concentrations remained within the target range for petunia in both the shoot tissue and root-zone for all substrates. In addition, there was no statistical evidence of N immobilization for any substrate blend for either of the N drawdown procedures. In both Expts. 1 and 2, root-zone nutrients became depleted during the consumer phase when irrigation was with clear water (no fertilizer), and petunia developed uniform symptoms of leaf chlorosis and N deficiency. Results of this study indicate that peat amended with 30% pine wood fiber, hammer-milled pine wood, and coconut can be used for production of containerized petunia with minimal effects on plant growth or need to adjust the fertilizer program. However, increasing pine wood to >30% of the substrate volume may require growers to increase fertilization and adjust irrigation practices to compensate for greater risk of N immobilization and changes in substrate physical properties.

Effects of Tree Species and Wood Fiber Size in the Core Layer on the Formaldehyde Emission of Three-Layers Fiberboard

Three-layered medium density fiberboards (MDFs) were produced using fine wood fibers in the face layers and coarse wood fibers in the core layer. The core layer were produced from pine wood fiber or beech wood fibers while the face fibers were produced pine fibers. The length of the beech fibers in the core layer increased from 4.3 mm to 28.2 mm while it increased from 4.9 to 29.1 mm for the pine fibers. The shelling ratio and panel thickness were 50/50 and 10 mm, respectively. Based on EN 120-method, the formaldehyde emission released from the MDFs were identified. The formaldehyde emission considerably declined with increasing fiber size at the same manufacturing parameters such as resin content, density, pressing parameters, and mat moisture content. Furthermore, MDF specimens having beech fibers in the core layer showed lower formaldehyde emission than that of the MDFs having pine fibers in the core layer.

Coconut Fiber Cement Panels as Wall Insulation and Structural Diaphragm

The study considers applications for natural fiber composites for affordable housing projects located in the two districts of Gujarat, India and Gorkha, Nepal with the goal of addressing issues of thermal comfort and lateral loading from seismic activity. To help alleviate some of these issues, the team worked with the Hunnarshala Foundation, in Bhuj, Gujarat, India, to develop a fiber cement composite that could be applied to the interior or exterior of a home and provide both insulative and structural improvements. Thermal conductivity of the composites were measured using a heat flux machine and experimental results of 0.16 W/m•K to 0.19 W/m•K showed an improvement in thermal conductivity compared to current wall cladding materials ranging from 1.60 - 1.88 W/m•K. Modeling of the building envelope was completed using the EnergyPlus™ tool and show that homes using the fiber cement composites would have an overall reduction in heating requirement of Nepalese homes by 14% and a reduction of 11% for homes in North India. The study used coconut husk fibers (referred to as coconut coir), rattan, and pine wood fibers in addition to Portland cement, fly ash, and hydrated lime in the fabrication of fiber cement composite samples. Flexural strength of these fiber samples were 70% stronger than comparison specimens, suggesting possible application for wall cladding to reduce out-of-plane failure during seismic events. Field tests conducted in Gujarat validated lab results as well qualitative perceptions of the material. Continued work with local partners presents several possible applications of coconut coir fiber cement composites for the retrofit existing housing and construction of new buildings.

Preparation of Medical Low-Temperature Wood-Plastic Polycaprolactone Composites and their Properties

Traditional medical external fixation material represented by gypsum is brittle, heavy and prone to adverse reactions, clinical effect is not ideal. The pine wood fiber particles (size for 10 ~ 40 mesh) and polycaprolactone (PCL) are used to prepare a new kind of wood-plastic polycaprolactone composites (WPC) by the blending method. The experimental results show that the increase of PCL mass ratio can enhance the material strength and flexibility, especially the match force between the pine wood fiber particles. Meanwhile, when the mass ratio of PCL reached 65%, this enhancement effect significantly diminished; after the mass ratio of PCL reached 70%, the phenomenon of material mechanics performance decline. In this paper, the prepared WPC, which can soften under temperature 50°Cand repetitively finalize the design, have good mechanical properties, low-temperature thermoplastic and environment protection.

Bamboo fibers for composite applications: a mechanical and morphological investigation

Bamboo fibers are very promising reinforcements for polymer composites production due to its high aspect ratio and strong mechanical performances. In order to better understand their reinforcing potential, the mechanical properties of single bamboo fibers extracted from eleven commercial bamboo species in China were measured with a newly developed microtensile technique. For comparison, the mechanical properties of mature single Chinese Fir and Masson Pine wood fibers were measured. The results show that the average longitudinal tensile modulus of the eleven kinds of bamboo fibers ranges from 25.5 to 46.3 GPa with an average value of 36.7 GPa. For tensile strength, the value ranges from 1.20 to 1.93 GPa with an average value of 1.55 GPa. The tensile strength and modulus of bamboo fibers are nearly two times of that of single Chinese Fir and Masson Pine fibers, and significantly higher than most of the published data for other softwood fibers. The average elongation at break of bamboo fibers is about 4.84 %, only a little lower than the value 5.15 % of the tested mature softwood fibers. Additionally, bamboo fibers were found to have smaller diameters and larger aspect ratio than most documented wood fibers, which favored an improved reinforcing effect. These combined mechanical and morphological advantages highlight the potential of bamboo fibers as the reinforcing phase in polymer composites for structural purpose.

Hydrogen adsorption by woodceramics produced from biomass

Hydrogen adsorption characteristics of woodceramics, made from radiata pine wood fiber boards carbonized at 1 473K after impregnation with phenolic resin, with and without chemical treatment in an alkaline (KOH) or an acid (H2SO4) solution were investigated The hydrogen adsorption capacity is improved by chemical treatment. The chemical treatment by KOH improves the adsorption capacity more than by H2SO4. The improvement of the capacity level, in any solution, is dependent on the type of chemical in the solution and its concentration. The maximum hydrogen capacity measured at 93K is mass fraction about w(H) = 2% for the woodceramics after chemical treatment in a volume fraction φ = 50% KOH solution, although that is about w(H) = 0.7% for one without chemical treatment. The microscopic condition of pores in the woodceramics is thought to vary after chemical treatment.

Natural Dyeing of Wood Fibers for Green Biocomposites

In this study, the mechanical and thermal properties of green biocomposites adding natural dye were investigated by tensile test and Differential Scanning Calorimetry (DSC). Poly(lactic acid), one of biodegradable polymers recently been interested for replacing petroleum-based polymers, was compounded with wood fibers to produce biocomposite, and natural dyes were introduced to improve appearance of biocomposite. Pine wood fibers were dyed with three types of natural dyes; yellow color from heartwood of Jackfruit tree, red color from Sappan wood, and blue color from Indigo blue. Prior compounding, original and dyed wood fibers were treated with silane to improve compatibility between wood fiber and polymer matrix. It is found that %crystallinity of alkali-treated and natural dyed wood/PLA biocomposites were significantly higher than original wood/PLA biocomposites. The modulus and tensile strength of natural dyed wood poly (lactic acid) composites were in the same level of alkali-treated wood composites; however, elongation at break was improved by natural dye.

Hypersensitivity Pneumonitis Related to Medium-Density Fiberboard

Pneumonitis due to hypersensitivity to wood fiber is mainly associated with the fungus that colonizes it. We present the case of a male affected with hypersensitivity pneumonitis in which the agent implicated was medium-density fiberboard, an engineered product whose main component is pine wood fiber. The causal agent was identified by means of a specific bronchial provocation test.

Neumonitis por hipersensibilidad en relación a madera de densidad media

Pneumonitis due to hypersensitivity to wood fiber is mainly associated with the fungus that colonizes it. We present the case of a male affected with hypersensitivity pneumonitis in which the agent implicated was medium-density fiberboard, an engineered product whose main component is pine wood fiber. The causal agent was identified by means of a specific bronchial provocation test.

Effects of Regenerated Cellulose and Natural Fiber on Interfacial Adhesion, Rheology and Crystallization Property in ε-Polycaprolactone Compounds

Regenerated cellulose fiber (RN) and natural fiber (pine wood fiber (PW)) filled ε-polycaprolactone (PCL) compound, PCL/RN (90/05 and 75/25 wt%) and PCL/PW (90/05, 75/25 and 50/50 wt%), are investigated with regard to interfacial adhesion, rheological properties, morphology, nucleation and mechanical properties. The interfacial adhesion of the RN filled PCL compounds shows better values than that of the PW filled ones. As the concentration of the RN and the PW particles is increased, the dynamic viscosity, the crystallization temperature and the elongation modulus are increased; however, the elongation strain is decreased. The viscosity of the RN filled compounds is higher than that of the PW ones at the same loadings. Striking differences are observed in elongation yield stress measurements. As the concentration of the particles is increased, while the elongation yield stress of the RN compounds is significantly increased, that of the PW compounds does not show significant improvement. More spherulites are locally developed on the RN surface than on the PW surface. We conclude the interfacial adhesion of the RN surface with the PCL is better than that of the PW surface with the PCL.

Analysis of Among-Species Variability in Wood Fiber Surface Using DRIFTS and XPS: Effects on Esterification Efficiency

Variability in the chemical composition of surface properties of various wood fibers (eastern white cedar, jack pine, black spruce, and bark) was investigated using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and X-ray photoelectron spectroscopy (XPS). Both DRIFTS and XPS showed high variability in fiber surface composition between species and between fiber types (sapwood, heartwood, and bark). Fiber surface was modified by esterification reaction using a maleic anhydride polyethylene (MAPE) treatment. DRIFTS failed to assess surface modification, whereas XPS results showed that MAPE treatment increased the surface hydrocarbon concentration of jack pine wood fiber, indicated by a decrease in oxygen–carbon ratio and an increase in relative intensity of the C1 component in the C1s signal. Lignin concentration variability on the fiber surface was determined as the major factor that prevents esterification from taking place.

Interfacial adhesion of cellulose fiber and natural fiber filled polypropylene compounds and their effects on rheological and mechanical properties

Rayon fiber (RN) and pine wood fiber (PW) filled polypropylene (PP) compounds, PP/RN (90/05 and 75/25 wt%) and PP/PW (90/05, 75/25 and 50/50 wt%), are investigated for their interfacial adhesion, rheological properties, morphology, nucleation and mechanical properties. The interfacial adhesion of the RN-filled PP compounds is better than that of the PW ones. As the concentration of the RN and the PW particles is increased, the dynamic viscosity, the crystallization temperature, and the tensile modulus are increased; however, the tensile strain is decreased. The viscosity of the RN-filled compounds is higher than that of the PW ones at the same loadings. Significant differences are found in the elongation yield test. As the concentration of the particles is increased, the elongation yield stress of the RN compounds is increased. Elongation yield stress of the PW compounds is decreased and more spherulites are locally developed on the RN surface than the PW surface. The interfacial adhesion of the RN surface with PP is better than that of the PW surface. The elimination of extractives on the PW surface improves the mechanical property of the PW/PP compounds; however, it reduces processability of the PW/PP compounds.

Accelerated Weathering of Modified Wood Flour Plastic Composites

The effect of accelerated weathering on the chemical and color of wood plastic composites (WPC) made from modified pine wood fiber (control, extractives free and holocellulose) was investigated. WPC were produced from the various wood fibers (60%, weight) and high density polyethylene (40%, weight) as matrix were subjected to accelerated weathering in xenon-arc weatherometer for up to 1200 hours. This study aimed at getting a better understanding of the chemical changes that occur to weathered WPC relative to its material compositions (wood and plastic). Chemical analyses and color measurement of the weathered surface using Fourier transform infrared (FTIR) spectroscopy, pyrolysis gas chromatograph mass spectrometry and colorimetery showed that degradation of WPC had occurred, causing color changes. It was observed that WPC made from holocellulose wood fiber had the lowest color change compared to extractives free wood and control wood fiber based WPC.