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Highly filled biocomposites may be used as biodegradable masterbatches that manufacturers add to traditional polymers for making plastic goods more biodegradable. Biocomposites based on various trademarks of ethylene-vinyl acetate copolymer (EVA) and natural vegetable fillers (wood flour and microcrystalline cellulose) were studied. The EVA trademarks differed both in terms of the melt flow index and in the content of vinyl acetate groups. The composites were created as superconcentrates (or masterbatches) for the production of biodegradable materials based on vegetable fillers with polyolefin matrices. The filler content in biocomposites was 50, 60, 70 wt.%. The influence of the content of vinyl acetate in the copolymer and its melt flow index on the physico-mechanical and rheological properties of highly filled biocomposites was evaluated. As a result, one EVA trademark with high molecular weight that has a high content of VA was chosen because of its optimal parameters for creating highly filled composites with natural fillers.

The performance of composites reinforced with natural fibers increases depending on the nature of the fibers and the type of surface treatment applied to the fibers. To improve the interfacial properties of the naturel fibers, one of natural fibers was selected (Wood Flour (WF)) and we introduced Graphene oxide (GO). The hydrogen bonding interactions between the Wood Flour and the GO facilitate the dispersion of the latter on the surface of the fibers to gives composite fibers (WF/GO). Several characterization techniques including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA) and Scanning electron microscopy (SEM) have been used to study the structural, thermal stability and morphological properties of the prepared hybrid composite. Morphological analysis revealed that the applied surface treatment of the Wood Flour (WF) was efficient where a good distribution of the GO sheets on the fiber interface is detected.

Didelis sukaupiamų atliekų kiekis ir neatsinaujinančių išteklių stokos grėsmė skatina ne tik pramonės, bet ir mokslo atstovus ieškoti inovatyvių, aplinkai draugiškesnių sprendimų. Šio darbo metu buvo sukurti nauji gumos-medienos kompozitai iš avalynės gamybos metu generuojamų etileno vinilo acetato ir buko medienos miltų atliekų. Sąveikai tarp kompozito komponentų padidinti buvo naudojamos selektyvaus sukepinimo lazeriu proceso metu susidariusios poliamido (PA) miltelių atliekos. Optinė ir elektroninė mikroskopija parodė, kad paruošti kompozitai pasižymi tolygia struktūra ir stipria sąveika komponentų tarpfazinėje riboje. Nustatyta, kad gumos ir medienos atliekų kompozitas buvo termiškai stabilus aukštesnėje nei 200 °C temperatūroje. Atliktų bandymų rezultatai atskleidė, kad medienos atliekų kiekiui išaugus iki 20 %, vandens absorbcijos vertės padidėja 40 %, o ištįsos trūkimo metu bei stiprio tempiant ir lenkiant – sumažėja vidutiniškai 45 %. Lyginant kompozitus su rišikliu, pastebėta, jog PA rišiklio įvedimas pagerina kompozito stiprį tempiant ir atsparumą lenkiant apie 80 %. Atlikti skaičiavimai parodė, kad komercines avalynės įdėklams formuoti skirtas EVA plokštes pakeitus šio darbo metu suformuotais kompozitais, įdėklų poros savikainą būtų galima sumažinti maždaug penktadaliu. Palyginus sukurto kompozito savybes su komercinėmis vidpadžiams ir įdėklams naudojamomis medžiagomis, nustatyta, jog jos galėtų būti pakeičiamos darbo metu pagamintomis kompozitinėmis plokštėmis., A large amount of accumulated waste and the threat of a lack of non-renewable resources encourage not only industry representatives, but also scientists to look for innovative and more eco-friendly solutions. The development of new rubber-wood composites from ethylene vinyl acetate and beech wood flour waste generated during footwear production is described in this work. Polyamide (PA) powder waste, generated during the selective laser sintering process, was used in order to increase the adhesion between the components of the composite. Optical and electron microscopy showed that developed composites have a uniform structure and a strong adhesive interaction at the interphase of the components. It was found that the rubber-wood waste composite is thermally stable when the temperature seeks above 200 °C. The results of the performed tests revealed that as the amount of wood waste increase by 20 %, the values of composite water absorption increase by 40 %, while the elongation at break and tensile/flexural strength decrease by 45 %. Comparison of the composites with and without PA binder revealed that the addition of PA binder improves the tensile and flexural strength of the composite by 80 %. The calculations showed that replacement of commercial EVA sheets with the created composites could reduce the cost of a pair of insoles by about a fifth. The comparison of the properties of the created composites and the materials, typically used for footwear insoles and inserts, showed that commercial panels could be fully replaced by the composites, which were developed during the work.

We evaluate the effect of the average particle diameter of wood flour on the physical and mechanical properties of a polymer composite material based on plasticised polyvinyl chloride. Рассмотрены вопросы оценки влияния среднего диаметра частиц древесной муки на физико-механические свойства полимерного композиционного материала на основе пластифицированного поливинилхлорида.

In this work, studies were carried out to assess the effect of the content of carboxymethyl cellulose and ethyl cellulose on the rate of biodegradation of composite materials based on carboxymethyl cellulose, ethyl cellulose, and wood flour. Приведены результаты исследований по оценке влияния содержания карбоксиметилцеллюлозы и этилцеллюлозы на скорость биоразложения композиционных материалов на основе карбоксиметилцеллюлозы, этилцеллюлозы и древесной муки.

In this paper studies were conducted to assess the effect of the degree of cellulose acetylation on the physical and mechanical properties of composite materials based on plasticized cellulose acetate with 50 % wood flour filling. Приведены результаты исследования по оценке влияния степени ацетилирования целлюлозы на физико-механические свойства композиционных материалов на основе пластифицированного ацетата целлюлозы с 50%-ным наполнением древесной мукой.

Приведены результаты исследования по оценке влияния содержания карбоксиметилцеллюлозы и этилцеллюлозы на свойства композиционных материалов на основе карбоксиметилцеллюлозы, этилцеллюлозы и древесной муки. In this work studies were carried out to assess the effect of the content of carboxymethylcellulose and ethylcellulose on the properties of composite materials based on carboxymethyl cellulose, ethyl cellulose and wood flour.

Wood plastic composites (WPC) were made from polypropylene (PP), impact copolymer (ICP) and wood flour (WF) by varying the WF content from 10 to 40% with PP grafted maleic anhydride as a coupling agent. The effect of varying WF content was studied on rheological, thermal, mechanical properties and dynamic mechanical properties. Experimental small amplitude oscillatory shear (SAOS) data was compared with the Einstein–Batchelor and empirical Krieger–Dougherty relations. Significant dependence of mechanical and rheological properties on WF content was observed. Young’s modulus, flexural modulus and dynamic shear viscosity increased with WF content. Results of dynamic mechanical analysis (DMA) showed increase in storage modulus with WF content. Three millimeter thick compression molded composites sheets were thermoformed using axisymmetric molds with two draw depths. Sag observed visually during thermoforming decreased with increasing WF content. Components made from the composites showed close to uniform thickness distribution as compared to those from ICP.

The efficacy of slow-release formulations of tribenuron-methyl (TBM) embedded in the matrix of degradable poly(3-hydroxybutyrate) blended with birch wood flour [polymer/wood flour/herbicide 50/30/20 wt.%] was compared with the efficacy of TBM as the active ingredient of the Mortira commercial formulation, which was applied as post-emergence spray to treat spring wheat cv. Novosibirskaya 15. The study was conducted in Central Siberia (in the environs of the city of Krasnoyarsk, Russia) from May to August 2020. The biological efficacy of the embedded TBM was 92.3%, which was considerably higher than the biological efficacy of the Mortira formulation used as the post-emergence spray (15.4%). The embedding of TBM into degradable blended matrix enabled long-duration functioning of this unstable herbicide in soil. The sensitivity of weed plants to TBM differed depending on the species. TBM was more effective against A. retroflexus and A. blitoides, which were killed at an earlier stage, than against C. album and G. aparine, whose percentage increased in the earlier stage and which were controlled by the herbicide less effectively and at later stages. On the plot treated with the embedded herbicide, the parameters of the wheat yield structure were the best, and the total yield was the highest: 3360 ± 40 kg/ha versus 3250 ± 50 kg/ha in the group of plants sprayed with the Mortira formulation. The grain produced in all groups was of high quality and was classified as Grade 1 food grain. The highest quality parameters (grain hectoliter mass, gluten, and protein contents) were obtained in the group of plants treated with the embedded herbicide. The study of the embedded TBM confirmed the high efficacy of the experimental formulation.

This study gives a first insight into the use of wood flour as a plant-based and cellulosic-based alter-native additive for newsprint and paperboard production using 100% recycled fibers as a raw material. The study compares four varieties of a spruce wood flour product serving as cellulosic-based additives at addition rates of 2%, 4%, and 6% during operation of a 12-in. laboratory pilot paper machine. Strength properties of the produced newsprint and linerboard products were analyzed. Results suggested that spruce wood flour as a cellulosic-based additive represents a promising approach for improving physical properties of paper and linerboard products made from 100% recycled fiber content. This study shows that wood flour pretreated with a plant-based polysaccharide and untreated spruce wood flour product with a particle size range of 20 μm to 40 μm and 40 μm to 70 μm can increase the bulk and tensile properties in newsprint and linerboard applications.

Пояснювальна записка до дипломного проекту на тему: «Виробництво ляльок з поліетилену із додаванням деревного борошна»: 87 сторінки, 17 рисунків, 25 таблиць, 21 посилання, 2 додатка. Розроблено проект технологічного процесу отримання ляльок з поліетилену методом ротаційного формування із додаванням деревного борошна. В проекті обґрунтовано вибір технологічної схеми, сировини та обладнання. Приведено характеристики сировини та обладнання, вимоги нормативних документів до них. Розраховано матеріальний баланс виробництва відповідно до заданої потужності, представлено тепловий баланс. Наведені описи засобів автоматизації технологічного процесу. Розглянуто заходи з охорони праці та безпеки життєдіяльності. Дано аналіз небезпечних і шкідливих виробничих факторів, визначена категорія приміщення за пожеже - та вибухонебезпечністю. Наведено основні техніко-економічні показники. Робота доповнена проектно-графічною документацією у вигляді креслень та схем. Explanatory note for science degree project on theme: “ Production of dolls from polyethylene with the addition of wood flour”: 85 pages, 17 figures, 25 tables, 21 sources, 2 appendixes. The project of technological process of polyethylene dolls producing with the addition of wood flour is devised. In project proved the choice of technological scheme, raw materials and equipment. Given characteristics of raw materials and equipment and demands of normative documents for it. Calculated material balance of processing corresponding to it’s productivity, heat balance is presented. Descriptions of the automation process. Reviewed the activities of labor protection and safety. An analysis of dangerous and harmful factors, defined category room on fire and explosion hazard. For the economic justification of engineering solutions. The work is completed graphic design documentation in the form of drawing sand diagrams.

The use of lignocellulosic fillers in rigid polyurethane foams (RPUFs) has been receiving great attention due to their good mechanical and insulation properties and the high sustainable appeal of the obtained cellular polymers, although high water uptakes are found in most of these systems. To mitigate this detrimental effect, RPUFs filled with wood flour (2.5% wt) were fabricated with the addition of furfuryl alcohol (FA) to create a polymer grafted with the wood filler. Two concentrations of FA (10 wt% and 15 wt%) were investigated in relation to the wood flour, and the RPUFs were characterized for cell morphology, density, compressive properties, thermal stability, and water uptake. The introduction of wood flour as a filler decreased the cell size and increased the anisotropy index of the RPUFs and, in addition to that, the FA grafting increased these effects even more. In general, there were no significant changes in both mechanical and thermal properties ascribed to the incorporation of the fillers. On the other hand, a reduction of up to 200% in water uptake was ascribed to the FA-treated fillers. This work was supported by the Coordination for the Improvement of Higher Education—CAPES (code 001), the National Council for Scientific and Technological Development—CNPq (Financial code 301758/2019-0) and the University of Basque Country (COLAB20/04).

The article determines the optimal content of the composition in the press-mold, which allowed obtaining biocomposite samples cylindrical chape without delamination and defects of structure due to the application of uniaxial compression load. The influence of wood flour on the viscosity of compositions based on starch gel was studied. The optimal content of aqueous solution of gluten in the composition was determined, which provided an increase in the hardness of biocomposite materials. The technology of obtaining starch gel and aqueous solution of gluten has been developed. The mode of formation of biocomposites under the influence of thermomechanical treatment with the following heat treatment of biocomposite samples was optimized, which ensured the formation of a dense and homogeneous structure of biocomposites.

Fused deposition modeling (FDM) 3D printing technology is the most common system for polymer additive manufacturing (AM). Recent studies have been conducted to expand both the range of materials that can be used for FDM and their applications. As a filler, wood flour was incorporated into poly lactic acid (PLA) polymer to develop a biocomposite material. Composite filaments were manufactured with various wood flour contents and then successfully used for 3D printing. Morphological, mechanical, and biodegradation properties of FDM 3D-printed PLA composites were investigated. To mitigate brittleness, 5 phr of maleic anhydride grafted ethylene propylene diene monomer (MA-EPDM) was added to the composite blends, and microstructural properties of the composites were examined by scanning electron microscopy (SEM). Mechanical strength tests demonstrated that elasticity was imparted to the composites. Additionally, test results showed that the addition of wood flour to the PLA matrix promoted pore generation and further influenced the mechanical and biodegradation properties of the 3D-printed composites. An excellent effect of wood flour on the biodegradation properties of FDM 3D-printed PLA composites was observed.

Wood plastic composite (WPC) is a green material with an excellent performance, environmental protection and recyclability, and potential in the field of green construction materials. A rheological study of WPC provides a key theoretical basis for mold design, equipment upgrade, production efficiency and quality improvement. In this study, an innovative approach was proposed to analyze the characters of a wood-flour/high-density polyethylene composite with an ultra-high wood-flour content (70 wt%–90 wt%, UWPC) in a shear flow field, including (1) a redesigned shear rheometer that can seal heat and (2) an analysis of the interactions between components in the UWPC by decomposing and calculating the stress during the rheological process. The stress that was generated by the UWPC melt during shearing originated mainly from wood particles and weak interfacial friction, whereas the stress that was generated by the polymer matrix could be ignored. Therefore, the polymer matrix served only to connect the wood particles and transfer stresses. Maleic-anhydride-grafted polyethylene (MAPE) enhanced the UWPC melt system interface, made the system structure more uniform and increased its fluidity. The enhancement effect of MAPE on the weak interface of UWPC melt was calculated quantitatively by calculating and analyzing the weak interfacial friction stress. The MAPE strengthening rate for the weak interface was 72.3%, 81.1% and 91.9% at 130 °C, 150 °C and 170 °C, respectively. These findings can be applied to improve WPC processing and equipment manufacture.

Outdoor building materials made of wood require preservatives containing chromated copper arsenate and other carcinogenic substances but still are subject to decay, hence they need to be replaced every few years. Wood-plastic composite (WPC) is an environmental-friendly composite of wood flour/fiber reinforced thermoplastic polymers (i.e., plastic). As WPC is made of plastic to evenly cover the wood flour, it has a lower moisture content than wood. In this study, maleic anhydride grafted polyolefin elastomers (POE-g-ma) and methyl methacrylate-butadiene-styrene copolymer (MBS) were used as impact modifiers to prepare WPCs from recycled polyethylene terephthalate (rPET) and recycled polyamide 6 (rPA6) blends (PET/PA6). The thermal properties of the WPCs with different mixing ratio polymer blends of rPET to rPA6 (E60/A40, E50/A50, and E40/A60) were investigated, as well as their mechanical properties after accelerated weathering. In addition, the creep behavior of the E40/A60 WPC under different environmental conditions was investigated. During the 10-h creep test, the POE-g-ma/WPC strain varied significantly more than MBS/WPC under environmental aging and higher loadings. The test results of impact and creep also show that the toughening effect of POE-g-ma/WPC was slightly better than that of MBS/WPC. In summary, the higher PET content resulted in lower flowability and a higher initial decomposition temperature, with the E60/A40 WPC having better anti-aged mechanical properties and more suitable for outdoor building applications.

Polyvinyl chloride/wood flour (WF)/organoclay (OMMT) ternary composites were prepared by melt blending. Chemically treated and untreated pine WF were used as filler, and organically modified montmorillonite or OMMT was added in order to get a potential synergy effect between polyvinyl chloride, untreated wood flour (UWF), or chemically treated WF. The OMMT loading in the composites was 0.5, 1, or 1.5 wt%. The chemically treated and UWF loadings were 1, 5, and 10 wt%. The composite specimens were subjected to mechanical tests (evaluation of tensile strength, elongation at break, and Shore A hardness), thermal stability (Beilstein test), processability characterizations, water resistance absorption, and morphological (optical microscopy) observations. The main results showed that the chemically treated WF were more efficient than the UWF for improving the mechanical and physical properties of polyvinyl chloride. Similar results were reported in the scientific literature. Therefore the chemically treated WF can be a cheap, eco-friendly, and renewable substitute for chalk as a filler which is normally used in the fabrication of Polyvinylchloride based cable insulators.

In this study, effect of wood flour addition on warm/cool feeling of green composite using wood flour and poly(lactic acid) was investigated for comfortability of interior product. Additive amounts of wood flour were 10 – 40 wt.%. Measurement of initial maximum values of heat flux of green composite using wood flour was conducted under constant temperature and humidity chamber. Surface of green composite using wood flour was observed by Scanning Electron Microscope (SEM). Following conclusions were obtained. The initial maximum value of heat flux of green composite decreased with an increase of wood flour additive amount until 20 wt.%. But, initial maximum value of heat flux of green composite at more than wood flour additive amount 30 wt.% almost did not change. From SEM observation, the appearance void area on surface of green composite at wood flour additive amount 20 wt.% was larger than that of green composite at wood flour additive amount 10 wt.%. Therefore, initial maximum value of heat flux of green composite was mainly affected because of increase of void area and wood flour until wood flour additive amount 20 wt.%.

Wood polymer composites (WPCs) are considered as one of the highly competent classes of hybrid composite materials having potential applications in automotive, furniture, and construction industry. In this present study, fabrication of PP-g-MA compatibilized PP-wood flour composites was accomplished utilizing melt blending extrusion. The extruder was operated at a temperature profile of 180–210 °C. Wood flour, prior to its incorporation in polymeric material, was sieved to get fine wood flour particles. Compression-molded specimens of composites were characterized for their morphological attributes and for the determination of their chemical makeup, mechanical features, and thermal stability. FTIR analysis determined the chemical makeup of WPCs. Thermogravimetric analysis revealed the thermal stability of composites at temperature higher than 280 °C. Composites were rated as V2 grade according to their flammability performance. SEM analysis manifested the dispersed state of wood flour in the PP matrix. Mechanical properties manifested the increased stiffness of WPCs owing to increase in loading of wood flour which was associated with the restricted motion of polymer chains imparted by the wood flour particles. Surface topology study of in-hole drilled surface was also carried out by performing machining of WPCs for the analysis of surface roughness as a function of drill speed. Furthermore, the environmental sustainability of WPCs machining was demonstrated, and the reduction in waste generation through drilling of composites was observed.

The rapid growth of polylactic acid (PLA) production and the slow hydrolysis rate make PLA a potential environmental pollutant. In order to make better reuse of the waste PLA in energy fields and solve the potential pollutant, PLA/wood flour (WF) compounds in all different proportions were co-pyrolyzed to study the co-pyrolysis behavior in terms of energy and products. The apparent activation energy of the 50%wtWF50%wtPLA compounds during co-pyrolysis decreased by 28% than PLA and 29.4% than WF. In addition, the pyrolysis of PLA provided additional energy for the co-pyrolysis of compounds which reduced the external input energy. The chemical reactions between WF and PLA during co-pyrolysis could be called synergistic interactions which promoted the free radical reaction of PLA and lead to the increase of lactide production. The yield of the harmful acetaldehyde reduced by 85.9% in the co-pyrolysis of 25%wtWF75%wtPLA compounds. In addition, the production of small molecular benzene ring substances was increased. For example, the phenol yield increased by 31.3% in the co-pyrolysis of 25%wtWF75%wtPLA compounds. The carbon number distribution of the main products was mainly concentrated on C5–C7 which was better for the reuse of bio-fuels during co-pyrolysis.

Polypropylene/wood flour composites having different nano-ZnO content were fabricated using melt compounding and subsequent injection moulding. The long-term water absorption and thickness swelling...

The results of assessing the possibilities of using of biomass of fallen leaves as a filler of composite polymer materials with a polyvinyl chloride polymer matrix are presented. Samples of composites with biomass of fallen leaves we obtained by extrusion and hot pressing method. The dependences of their physical and mechanical properties on the content of the filler were determined. These de-pendencies are given in the form of polynomial of the second degree. In terms of most physical and mechanical properties (with the exception of impact strength) composites with biomass of fallen leaves are superior to samples of wood-polymer composites with wood flour with a similar degree of filling. Made of a comparison of the effectiveness of three different plasticizers: dimethyl phthalate, dibutyl phthalate and dioctyl therephthalate. The most promising is the use of dibutyl phthalate as a plasticizer. It has been shown that the biomass of fallen leaves is an effective replacement for wood flour in the production of wood-polymer composite materials with a s fr.

Application of out-of-service rubber from a variety of sources is of both environment-protecting and resource-saving importance. To that end, recycled tire rubber was utilized as a filler to fabricate wood-high density polyethylene (HDPE) composite with enhanced toughening performance using the injection procedure in this work. Dosages of rubber powders were 0, 5, 10, and 15wt% based on the overall weight of poplar wood flour and HDPE (HDPE: wood flour = 70꞉30). The injection-fabricated composites were subjected to a four-cycle repetitive compressing loadings (0–3 kN) and dynamical mechanical analysis (DMA, room temperature to 150 ℃, in the dual cantilever mode). It was found that the rubber-filled materials exhibit advantageous energy absorption performance compared to wood-HDPE composites under repetitive compressions. The rubber-filled wood-HDPE composites are thermomechanically labile in an environment with raised temperature. The HDPE matrix substance occupies the predominant role in thermally yielding of the overall composite, typically in the temperature range of 50–75 ℃ resulting in a loss modulus peak. Up to 130–150 ℃, all the composites fully loses their moduli with loss factor (Tanδ) reaching its peak values of 0.30–0.38. To conclude, rubber-filled wood-HDPE is a qualified material applicable in proper temperature range.

Although applications of wood-plastic composites (WPC) have rapidly increased, the raw materials used for producing WPC are still sound wood until now. The decayed wood usually is discarded or used as fire wood, which causes a serious waste of resources and environmental pollution. However, the decayed wood contains high lignin content which can be used for producing polymeric materials. In this study, decayed wood plastic composites (DWPC) with nano calcium carbonate (NCC), activated carbon (AC) and chitosan (CS) were fabricated and sound wood plastic composites (SWPC) without any additive were prepared. Compared to the results of physical and chemical properties of DPWCs with SWPCs, it was found that the mechanical properties, chemical structure, thermal stability, degree of crystallinity (Cr) and flame retardancy of DWPC with CS were better than DWPC without any additive, and even better than SWPC. The addition of CS (4%) to decayed wood powder (about 30%) and PVC (about 70%) could improve the physical, chemical, and bonding properties of DWPC, which could reach the level of sound wood plastic composites. The results of this work proposed a novel green strategy for utilizing decayed wood for making polyvinyl chloride/wood flour composites.

This study investigated the effect of pressurized temperature on the thermal, mechanical, and morphological properties of nanocomposites made from recycled polyethylene with the weight ratio of 50%. Nanosilica was applied at 3 levels (0, 4, 8 %) and wood flour had a weight ratio of 50%. High-density polyethylene (HDPE) went through multiple procedures. It was found that by increasing the nanosilica content, the tensile and flexural strength properties, the residual ash content, and the thermal stability increased along with a reduction in the tensile and flexural modulus and impact resistance. As the temperature increased, the tensile and flexural strength and modulus and the impact resistance decreased. Scanning electron microscopy (SEM) images revealed that samples with 8% nanosilica showed different polymerization than the wood flour particles.

The use of polymeric materials for the sustainable packaging sector is constantly improving due to meet the required properties for the application. However, most polymers come from non-renewable s...

Highly filled bio-composites based on ethylene-vinyl acetate copolymer (EVA) with cellulose and wood flour were prepared in the previous parts of the study. The aim of this work was to dilute them with a polyethylene (PE), to prepare new bio-composites with lower EVA content and to investigate the effect of EVA/PE ratio on the mechanical properties. It was shown that melt flow index (MFI) and elongation at break increased additively with an increase of EVA content in the composition, but yield strength had an inverse tendency. The obtained results are extremely useful for choosing the right composition for the industrial implementation.

With the depletion of fossil fuel energy and both the slow development and low utilization rate of new eco-friendly energy, finding new ways to efficiently store energy has become a research hotspot. Presently, polyethylene glycol (PEG) is an excellent heat storage material, but it is a typical solid-liquid phase change material (PCM) with a risk of leakage during phase transition. A combination of wood flour (WF) and PEG can effectively eliminate the risk of leakage after the melting of PEG. However, WF and PEG are both flammable materials, which impedes their application. Therefore, it is of great significance to expand their application by forming composites from among PEG, supporting mediums, and flame-retardant additives. This will improve both their flame retardancy and phase change energy storage performance, and will also lead to the preparation of excellent flame-retardant phase change composite materials with solid-solid phase change characteristics. To address this issue, ammonium polyphosphate (APP), organic modified montmorillonite (OMMT), and WF were blended into PEG in specific proportions to prepare a series of PEG/WF-based composites. Both thermal cycling tests and thermogravimetric analysis results demonstrated that the as-prepared composites had good thermal reliability and chemical stability. In addition, during differential scanning calorimetry tests, the PEG/WF/8.0APP@2.0OMMT composite presented the highest melting latent heat (176.6 J/g), and its enthalpy efficiency reached more than 98.3%. The PEG/WF/8.0APP@2.0OMMT composite also exhibited superior thermal insulation performance when compared to the pure PEG/WF composite. Furthermore, the PEG/WF/8.0APP@2.0OMMT composite exhibited a significant 50% reduction in peak heat release rate as a result of the synergistic effect between OMMT and APP in the gas and condensed phases. This work offers a useful strategy for the fabrication of multifunctional phase-change material, which is expected to broaden its industrial applications.

Graphene nanoplatelets (GNP) are used to produce wood plastic composites (WPC) with improved electrical and thermal conductivity. The polypropylene/wood/GNP hybrid composites are produced by melt compounding followed by hot pressing. The effect of GNP loadings (5, 10 and 15 wt%) on electrical conductivity, thermal conductivity, tensile properties, and thermal degradation of hybrid WPC containing 20 wt% of wood flour is studied. The effect of fast and slow cooling rates during hot pressing on the surface resistivity of hybrid WPC is evaluated. Scanning electron microscopy of the tensile fracture surface and polished cross-sections of hybrid WPC is analysed. The hybrid WPC containing 20 wt% wood flour and 15 wt% of GNP (PP-W20-G15) is measured to show surface resistivity of 2.05E + 06 Ω/sq and thermal conductivity of 0.61 W/m.K. There is a significant increase in electrical and thermal conductivity of PP-W20-G15 when compared to WPC containing 20 wt% of wood flour (PP-W20). The wood flour helps with the distribution of GNP in PP-W20-G15 by which the surface resistivity is improved when compared to PP filled with 15 wt% GNP. It was found that the surface resistivity of PP-W20-G15 was dependent on the cooling rate used during the hot pressing. There is a considerable decrease in tensile strength and an increase in the tensile modulus of hybrid WPCs compared to PP-W20 and neat polypropylene.

The potential utilization of melamine impregnated paper (MIP) waste in thermoplastic composites was investigated. Composites were also manufactured utilizing wood flour (WF) at the same filler rates for comparison. The composites were manufactured using a compression molding method. The effects of filler type and filler rate on the mechanical properties of low-density polyethylene (LDPE)-based composites were evaluated. Mechanical properties, such as tensile and flexural strengths, were determined in accordance with ASTM D638 (2001) and ASTM D790 (2003), respectively. Results showed that filler type and filler content had significant effects on all mechanical properties investigated. Both fillers improved all mechanical properties except for tensile strength and elongation at break of LDPE. In conclusion, MIP waste has a potential to be utilized in thermoplastic-based composite manufacturing and might generate some economic and environmental benefits.

In this study, maleic anhydride grafted polypropylene (MAPP) was incorporated as coupling agent in the wood-flour/polypropylene/ammonium polyphosphate composites (flame-retardant WPCs). The effects of MAPP content (5 wt.%, 10 wt.% and 15 wt.%) on the physical, mechanical and flammability properties of flame-retardant WPCs were investigated. The water soaking tests showed that the incorporation of MAPP could reduce the hygroscopicity of flame-retardant WPCs. The mechanical properties of WPCs were evaluated by three-point bending tests, unnotched Izod impact strength tests, and dynamic mechanical analysis. The results showed that the flame-retardant WPC containing 10 wt.% MAPP (WPC/APP/MAPP-10 %) performed the best flexural properties, the highest impact strength, E′ value, and tan δ at room temperature. The limiting oxygen index (LOI) tests and cone calorimetry tests showed that the incorporation of 10 wt.% MAPP endowed the flame-retardant WPC with the highest LOI value, the lowest peak-heat release rate, total heat release, CO/CO2 weight ratio and total smoke release. Moreover, the characterization of the WPCs combustion residues performed that WPC/APP/MAPP-10 % had the most complete carbonaceous structure with the highest graphitization degree after combustion. In general, the addition of 10 wt.% MAPP could impart the flame-retardant WPC with the optimum physical-mechanical properties and flame-retardant performance.

The synergistic effect of fire retardant agents, nanoclay (NC), aluminum trihydrate (ATH) and Hisil on the physico–mechanical properties, thermal degradation and flame retardance performance of wood flour/waste polypropylene composites (WF/WPP) was studied. The prepared composites were irradiated with gamma radiation doses of 10 and 20 kGy. The developed nanocomposites were characterized by mechanical, thermogravimetric (TGA) and flammability measurements. The results indicated that the synergistic effect of the fillers, 10 phr NC and 5 phr Hisil, was found greater than that of 10 phr NC/5 phr ATH or NC alone. Loading the fabricated composite with 5 phr ATH or Hisil created a good fire retardant wood possessing many advantages of fireproof, waterproof, moistureproof, chemical resistance and environmentally friendly features. Similarly, the application of gamma irradiation led to an overall improvement in the mechanical, physical and thermal stability of the prepared composites.

Wood plastic composites (WPCs) consisting of high density polyethylene (HDPE) reinforced with high-loading (55 wt%) of wood flour (WF) were fabricated with melt-blending technique. In this compounding method, processing parameters such as different mixing temperatures (of 165, 180 and 195°C), mixing times (of 5, 10 and 15 minutes) and coupling agent contents (of 2 and 4 wt%) were evaluated. Prepared specimens were analyzed with tensile, Izod, shore D, DMTA, short-term creep, DSC, TGA, water absorption and water contact angle characterizations. Results revealed that mixing temperature of 180°C, mixing time of 10 minutes and coupling agent concentration of 4 wt% were found as the best processing conditions. The mentioned conditions provided enhanced dispersion of WF particles within the HDPE matrix, due to optimum viscosity of the polymer melt and effective residence time of compound in the mixer, and beside them efficient interfacial adhesion between WF and polymer matrix.

Poly Lactic Acid biopolymer was fabricated through four different methods namely Stir Casting, Injection moulding, Extrusion and compression moulding. The pure polymer sample was processed in these different methods to determine the impact of different processing methods on the mechanical property (tensile strength) of PLA. Tensile test was carried out to ASTM D628 standard for all the samples that were fabricated. The tensile strength of the samples that were fabricated through injection moulding, extrusion and compression moulding (named IPLA, EPLA and CPLA respectively) had very marginal difference between themselves while the one fabricated through stir casting method (named as SPLA) had a tensile strength reduced to one third of the value of the result that was obtained through the samples that were processed using the former methods. On conducting further experimentation with 20 wt% wood flour reinforcement into PLA to obtain a Wood Plastic Composite (WPC) and repeating the same processing and testing method, the tensile strength of the wood flour reinforced composites were found to increase in all the four cases of processing methods when compared to their plain polymer products correspondingly. Similar to the plain polymers the tensile strength of the composites also showed marginal difference between themselves in the Injection moulded, extruded and compression moulded methods while the stir casted composite surprisingly resulted in the same one third reduction in tensile strength that was seen on the plain polymers when compared with the former methods. The final verdict of the investigations is that stir casting method is effective and the cheapest processing method of all, the weight of the stir casted polymer and its composite was the lowest among all the processing methods respectively, the mechanical properties (especially tensile strength) of the stir casted polymer and its composite was exactly one third of the value that was obtained through the other regular processing methods that use pressure.

This paper investigates the mechanical properties of wood plastic composite which was made by using recycled High-Density Polyethylene (HDPE) and Polypropylene (PP) with Teak wood flour. Multi-Walled Carbon Nanotubes were used as additional filler. The composite was made using single screw extruder having L/D ratio 20. The RPM of the screw was fixed at 15 RPM and the temperature of the feed, metering and transition zone was maintained at 130°C, 1900c and 220°C respectively. Dimensional stability and mechanical properties of the composite were improved by coupling agents. Wood floor was used at 10wt% and MWCNTs were taken between 0.1 to 1 wt %. Increasing filler load improves compressive strength of the composite. The addition of MWCNT to HDPE/WF composite results in significant increment in compressive strength of the composite.

Natural fibers have grown extensively during the last few years and have become interesting to scientists and researchers as an alternative preference for wood dust fiber composites. As they have good mechanical properties, cost adequacy, non-abrasiveness, high particular quality, eco-accommodating, and biodegradability features. They are abused as a trade for traditional fibers like carbon and glass. In present correspondence, the study on the preparation and characterization of a new arrangement of green composites, including Tectona Grandis wood flour fiber as a strengthening material in polymer grid based on epoxy resin has been accounted. The stable mechanical properties of erratically orientated personally blended Tectona Grandis wood flour fiber-reinforced polymer green composites such as tensile, compression, and hardness properties were explored as a purpose of fiber loading. The reinforcement of resin with Tectona Grandis wood dust fiber is accomplished in particulate fiber by employing optimized resin. These fibers were blended with epoxy resin in diverse fortification strengthening percentages. The outcome of the above said mechanical properties were measured. It has demonstrated a development in these stable mechanical properties after reinforcement by fibers. The estimation of static mechanical properties will increment in an increasing percentage of reinforcement. The average ultimate tensile strength is 17.50 MPa, and the compression strength is 246.93 MPa. The microstructural behavior of these composites is studied with the help of scanning electron microscopy (SEM), and the moisture absorption test is also carried out.

The paper presents the results of a comparative study of the physics and mechanical, rheological and biodegradation characteristics of composite materials based on a mixture of polyethylenes of low (LDPE 273-83) and high (HDPE 15303-003) pressure in a ratio of 1:1. The composite was also filled with finely ground wood flour with a particle size of less than 200 microns (5-30% by weight) and 10% compatibilizer (functionalized by the alkaline alcoholysis splitting method of sevilene (EVA 12206-007) and a processing additive of 1% polyethylene glycol (PEG-115 (4000). It has been found that with an increase in the content of wood flour (up to 20%), the modulus of elasticity and ultimate strength practically have not changed. The tensile elongation of the composite exceeds 100% (if the content of wood flour is up to 15% by weight). The complex viscosity and shear modulus of the considered melts with different filler contents are practically at the same level. At the same time, the introduction of wood flour up to 30% and a compatibilizer (10%) promotes a slight increase in the viscosity and elasticity of melts, which practically does not affect the change in the manufacturability of the compositions in comparison with LDPE 273-83. For a comparative assessment of the ability of composites to biodegradation, moisture absorption, chemical oxygen consumption, and weight loss of composites in laboratory soil during exposure for 12 months were studied. It has been shown that as the filler content increases, the biodegradability of composites increases., В работе представлены результаты сравнительного изучения физико-механических, реологических и биодиструкционных характеристик композиционных материалов на основе смеси полиэтиленов низкого (ПЭНД 273-83) и высокого (ПЭВД 15303-003) давления в соотношении 1:1 наполненных тонкоизмельченной древесной мукой с размером частиц менее 200 мкм (5–30% по массе) в присутствии 10% компатибилизатора (функцианализированого методом щелочного алкоголиза севилена (СЭВА 12206-007)) и технологической добавки 1% полиэтиленгликоля (ПЭГ-115 (4000)). Установлено, что по мере увеличения содержания растительного наполнителя (до 20%) модуль упругости и предел прочности практически не изменятся. Относительное удлинение композита при растяжении превышает 100% (до содержания древесной муки – 15% по массе). Комплексная вязкость и модуль сдвига рассматриваемых расплавов с различным содержанием наполнителя находятся практически на одном уровне. При этом введение древесной муки до 30% и компатибилизатора (10%) способствует незначительному увеличению вязкости и упругости расплавов, что практически не влияет на изменение технологичности композиций по сравнению с ПЭНД 273-83. Для сравнительной оценки способности композитов к биодеструкции исследованы влагопоглощение, химическое потребление кислорода и потеря массы композитов в лабораторном грунте при экспозиции в течение 12месяцев. Показано, что по мере увеличения содержания наполнителя способность композитов к биодеструкции усиливается.

Cast polyamide 6 (PA6G), trade name Castamide, is a semi-crystalline polymer widely used in the engineering plastics industry. There is a need to recycle valuable waste (W)-PA6G generated during part manufacturing of this polymer (approximately 30%). This study attempts to utilize W-PA6G in the manufacture of wood-plastic composites as a polymeric matrix. The effect of lignocellulosic filler type (FT) and filler content (FC) on the mechanical, morphological, and thermal properties of W-PA6G-based composites were investigated. During manufacturing, N-butyl benzene sulfonamide (N-BBSA) and lithium chloride (LiCl) were utilized as a plasticizer and a melt temperature-lowering salt, respectively. The rice husk (RH) and Uludağ fir wood flour (WF) filled W-PA6G-based composites were successfully manufactured using a combination of extrusion and injection molding. Compared to RH filled composites, WF filled composites provided better tensile and flexural properties (both strength and modulus) at 20% and 30% filler contents. Morphological study showed the nonhomogeneous distribution of fillers in the polymeric matrix. Lignocellulosic filler resulted in reduced melting temperature and crystallinity of W-PA6G-based composites. This reduction was more pronounced in RH filled composites.

Rigid polyurethane biofoams (RPUF) were produced by single shot-method using a bio-based polyol and 10 wt% of pinewood particles. Two different confinement degrees were investigated (70% and 50% of the free-rising volume), along with a control group produced under free-rising. RPUF were studied using SEM images (to estimate average foam cell size and anisotropy index), mechanical testing (under compression and tension), apparent density, and thermal conductivity analysis. The results were statistically evaluated using ANOVA tests prior to means tests. The RPUF produced under confinement showed more rounded and homogeneous cell structures compared to those freely expanded. The filled RPUF produced under a confinement degree of 50% yielded very high compressive and tensile strengths, whereas thermal conductivity decreased with confinement.

Aiming the development of novel composites reinforced with natural fibers from vegetable origin, it is important the understanding and control of processing parameters in twin-screw extruders. The temperature profile and the screw components, as well as the extrusion speed, compromise the distribution and dispersion of the fibers in the matrix and consequently in their rheological behavior, which reflects in the mechanical, chemical and morphological properties of the composites and products obtained from them. One new tool, used to understand processing parameters in composites, is computer simulation. In this study, we used the WinTXS Software to evaluate the influence of process parameters in the polypropylene matrix composite reinforced with 30 vol% wood flour. Parameters such as shear rate, temperature, melt viscosity, and viscous dissipation were evaluated. It was observed that increasing screw speed, the temperature increased, which results from the viscous dissipation. Under these conditions, the shear rate and melt viscosity were reduced.

The water transport kinetics and moisture-induced thickness swelling behavior of wood-plastic composites (WPCs) in the presence of two imidazolium-based ionic liquids (ILs) were studied. The wood flour chemically treated with ILs were compounded through melt mixing of high-density polyethylene and coupling agent, and finally, the test specimens were produced by compression molding. Hygroscopic rates of the composites were evaluated by immersing them in the water at room temperature and monitoring moisture sorption and thickness changes for several weeks. Besides, the water diffusion coefficients and swelling rate parameters were measured for all composites. It was found that the water absorption and thickness swelling of the WPC specimens reduced as a result of ILs treatment. The SEM analysis revealed that the presence of ILs can improve the quality of adhesion between the polymer matrix and the cellulosic materials, to decrease the gaps in the interfacial region and block the hydrophilic groups. Studying the water sorption process in the specimens showed that the process follows kinetics and mechanisms described by Fick’s law. The highest water diffusion coefficients and swelling rate parameters were found in composites with untreated wood.

Red Balau saw dust was heat-treated at 180 °C and 200 °C for one hour and compounded with low-density polyethylene, LDPE, at 9, 20 and 37 wt%. The compounded materials were injection moulded into test specimens. Charpy impact assessment of the notched samples of the composites revealed that the peak load, P, and the critical stress intensity factor, Kc, increased with wood content and treatment temperature. While the energy to failure, W , and the critical strain energy release rate, Gc, decreased with wood content, the values were highest in composites made from wood flour treated at 180 °C and reduced in 200 °C treated wood composites. This behaviour revealed that heat treatment of wood flour at the 200 °C resulted in poorer impact properties of the composites. Dynamic mechanical analysis showed an increase in storage and loss modulus of composites made from untreated wood flour relative to the heat-treated ones. Tan delta values were also found to reduce in the heat-treated wood composites as a result of decreased damping. Heat treatment of wood flour at appropriate temperature enhanced both the mechanical and dynamic mechanical properties of the composites.

Mechanical properties of two samples of decking boards were measured after exposure in rain and chlorinated water, in ice, and in a mixture of gasoline and water in different concentrations from 1 to 7%. Samples consisting of 60% wood flour, 30% polyvinyl chloride and 10% additives were used for measurements. Additives are flame retardants, stabilizers, modifiers and dyes. The mineral filler CaCO3 was used as modifiers. For sample №1, the CaCO3 content was 42% and the wood content was 18%. For sample №2, the CaCO3 content was 24% and the wood content was 36%. As a result of measurements after exposure for 150 days, it was found that the specific impact strength increases by 120%, the bending strength decreases by 60%, and the Shore D hardness decreases by a maximum of 10%. Consequently, decking boards can be confidently used for a long time, since a number of properties almost do not change, but even increase, and some decrease in strength remains within acceptable values.

Wood polymer composites (WPCs) were prepared via compression molding technique using wood flour and methacrylic anhydride modified epoxidized soybean oil (MAESO) copolymerized with triallyl maleopimarate (TMPA). Various percentages of TMPA were incorporated into the composite system to compare the properties of the final WPCs. TMPA was synthesized from rosin acid and the chemical structure was characterized by 1H-nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy. The interaction between wood flour, MAESO and TMPA were revealed by FTIR and scanning electron microscope (SEM) study. Results demonstrated that TMPA was effective in enhancing the mechanical and thermal properties of the composites. Flame retardancy, biodegradability, chemical resistance, and dimensional stability significantly improved after the incorporation of TMPA into the composites. Wood polymer composites loaded with 30 wt% of TMPA exhibited maximum improvement in properties compared to other systems.

Using NaOH/ urea solution to partially dissolve wood flour, a novel nano-TiO2 photocatalytic composite was prepared by hydrothermal method with insoluble wood flour as bio-carrier and dissolved components of wood flour as accelerant. SEM results showed that the control sample prepared without adding titanium sulfate consisted of insoluble wood flour and still possessed unbroken fibers after hydrothermal treatment. The control sample prepared without wood flour addition was only composed of TiO2 micro-particles. With assistant of the dissolve components of wood flour, nano-TiO2 with the size of 50−300 nm was well assembled on the surface of insoluble wood flour. The composite is composed of anatase TiO2 and insoluble wood flour and possess high specific surface area. The absorption edge of composite extended to the visible light range. The composite exhibited high removal rate of methylene blue, up to 97.7% within 120 min. This performance was even better than commercial TiO2 (P25) with the rate of 81.8%. The reused performance of the composite retains removal rate of 90.7% even after 5 cycles. The environment-friendly nano-TiO2 photocatalytic composite can be very useful for degrading refractory organic pollutants.

Green composites are a special class of composites in which at least one of the components is obtained from natural resources. They are an alternative to traditional composites because of their useful properties such as biodegradability, low cost, easy processability, sound insulation and recycling. Green composites, which emerge as environmentally friendly polymeric composite materials, offer techno-economic advantages in commercial and engineering applications and are among the widely dealt subjects due to the very high demand from the global market. The aim of this study is to investigate the effect of chestnut wood flour size on the mechanical properties of chestnut-wood-flour-filled vinyl ester composites. With this aim, composite specimens were produced by using vinyl ester polymer as the matrix material and chestnut wood flour in three different sizes (0–150, 150–315 and 315–400 μm) as the natural filler. In each size combination, four different matrix/filler ratios (5, 10, 15 and 20% by weight) were adopted. These mixtures were then poured into Teflon moulds to produce the test specimens. Izod impact, three-point bending, hardness and tensile strength tests were performed on the composite specimens. In addition, morphological investigations were performed on the fractured surfaces of the specimens by using scanning electron microscopy. It is concluded that composites with a small-sized chestnut wood flour as the filler have superior properties for composite applications.