Academic literature on the topic 'Recycled cellulose fibre'

Environmental and open public health aspects have an important and increasing role, especially in the exploration of natural fibers from recycle materials. The aim of this study is to synthesis cellulose from office waste paper and use it as a reinforcement filler to develop biocomposites. Epoxy reinforced kenaf fiber and cellulose composite were prepared in this study using polymer casting technique consisting of grinded kenaf fibre (natural fibre) 5% and epoxy 95% as reinforcement element. Cellulose was synthesized from recycled office papers and used as a filler to prepare cellulose/kenaf reinforced epoxy composite. Effect of cellulose to the mechanical properties of the composite were investigated. Samples were fabricated by weight percentage of 0%, 0.5%, 1.0%, 1.5% and 2.0% of cellulose content. For mechanical properties impact test, Rockwell harness and tensile testings were conducted.

AbstractNowadays, there is paying an attention to the utilization of natural, renewable and biodegradable resources of raw materials of lignocellulosic character, residues from agricultural crops and wood processing as well as waste from papermaking industry in building composite materials preparing. Also recycled fibres coming from waste paper are considered as valuable material. The objective of this study is to utilize these recycled cellulosic fibres into cement composites and characterise their impact on resulting physical and mechanical properties of fresh and hardened cement composites. Manufactured cement composites contained 0.2%, 0.3% and 0.5% addition of cellulosic fibres. In fresh fibre cement mixtures reduction in workability with increasing amount of cellulose fibres was noticed. Density as well as compressive and flexural strength of 28 and 90 days hardened fibre cement composites was tested. Distribution of cellulosic fibres with 0.5% addition in hardened fibre cement composites was also observed. The results of density determination of 28 and 90 days hardened fibre cement composites showed reduction in their values related to weight lighter concretes. Compressive strengths of fibre cement composites have shown decreasing character with increasing added amount of cellulosic fibres into the mixture up to 0.5%. Maximal decrease in compressive strength values was observed in composites containing 0.5% of cellulosic fibres. However, obtained strength parameter values of hardened composites had satisfying results for their application in construction as non-load bearing building material.

This paper presents an experimental study of the effect of adding recycled cellulose fibres on physical, thermal, and mechanical properties of lightweight concrete composites. Results show an important decrease of density and thermal conductivity with an increase of fibre content. Compression and flexural strength decreased with fibre content, but remained within the standard range for hollow non-load-bearing concrete masonry (ASTM C109/C 109-95) for the maximum fibre content (15%).Key words: mortar composite, mineral matrix, cellulose fibre, thermal conductivity, mechanical strengths.

Circularity of cellulose-based pre- and post-consumer wastes requires an integrated approach which has to consider the characteristics of the fibre polymer and the presence of dyes and additives from textile chemical processing as well. Fibre-to-fibre recycling is a condition to avoid downcycling of recycled material. For cellulose fibres regeneration via production of regenerated cellulose fibres is the most promising approach. Textile wastes contain dyes and additives, thus a recycling technique has to be robust enough to process such material. In an ideal case the reuse of colorants can be achieved as well. At present nearly 80% of the regenerated cellulose fibre production utilises the viscose process, therefore this technique was chosen to investigate the recycling of dyed material including the reuse of the colorant. In this work, for the first time, a compilation of all required process steps to a complete circular concept is presented and discussed as a model. Indigo-dyed viscose fibres were used as a model to study cellulose recycling via production of regenerated cellulose fibres to avoid downcycling. Indigo was found compatible to the alkalisation and xanthogenation steps in the viscose process and blue coloured cellulose regenerates were recovered from indigo-dyed cellulose. A supplemental addition of reduced indigo to the cellulose solution was also found feasible to adjust colour depth in the regenerated cellulose to the level required for use as warp material in denim production. By combination of fibre recycling and indigo dyeing the conventional yarn dyeing in denim production can be omitted. Model calculations for the savings in water and chemical consumption demonstrate the potential of the process. The proportion of the substitution will depend on the collection rate of denim wastes and on the efficiency of the fibre regeneration process. Estimates indicate that a substitution of more than 70% of the cotton fibres by regenerated cellulose fibres could be achieved when 80% of the pre- and post-consumer denim wastes are collected. Therefore, the introduction of fibre recycling via regenerated cellulose fibres will also make a substantial impact on the cotton consumption for jeans production.

Kalipoh Village, Ayah Discrit Kebumen, Regency is a waste-producing area such as waste paper, coconut fibre and cassava peels that have not been well managed. The impact of this waste can cause environmental health problems. These three types of waste have cellulose content that can be utilized to make recycled paper. This study aims to determine water absorption, tensile strength, and community acceptance with pre-experimental research design posttest only design analyzed descriptively. The results showed that the best water absorption strength and paper tensile strength were a variation of 1: 1: 2 with a yield of 76 mm and 2,683 N / mm. Whereas based on the result of physical test and public acceptance that recycle paper of variation I have a slightly coarse texture, the fibre is slightly visible and the pale; variation II has a coarse texture, visible fibre and pale colour, while variation III has a rather coarse texture, rather visible fibre and vibrant colour. The community also deeply appreciates the innovation of recycled paper making.

Worldwide demand for man-made cellulosic fibres (MMCF) are increasing as availability of cotton fibre declines due to climate change. Feedstock for MMCF include virgin wood, agricultural residues (e.g., straw), and pre- and post-consumer cellulosic materials high in alpha-cellulose content. Lyocell MMCF (L-MMCF) offer large advantages over other MMCF processes in terms of both environmental and social impacts: the solvent for cellulosic dissolution, n-methyl-morpholine-n-oxide, can be recycled, and the process utilizes non-toxic chemicals and low amounts of water. Hemp can be a preferential cellulosic feedstock for L-MMCF as hemp cultivation results in carbon dioxide sequestration, and it requires less water, fertilizers, pesticides, and herbicides than other L-MMCF feedstock crops. These factors contribute to hemp being an environmentally conscious crop. The increased legalization of industrial hemp cultivation, as well as recent lifts on cannabis restrictions worldwide, allows accessibility to local sources of cellulose for the L-MMCF process. In addition, hemp biomass can offer a much larger feedstock for L-MMCF production per annum than other cellulosic sources, such as eucalyptus trees and bamboo. This paper offers perspectives on the agricultural, manufacturing, and economic opportunities and challenges of utilizing hemp biomass for the manufacturing of L-MMCF.

Abstract The degradation of paper-based materials involves several and complex mechanisms, such as hydrolysis and oxidation. The behaviour of different types of pulps can be very variable. In this study, the difference upon oxidation of contemporary non-recycled and recycled papers, which now constitute a considerable fibre source, is investigated. A 0.015 M potassium periodate solution is used to oxidise five types of paper, two non-recycled and three recycled, for 0.5, 1, 2 and 4 h. The effects of such oxidation treatments are evaluated in terms of carbonyl content and degree of polymerisation (DP). A modified procedure of the Szabolcs’s method and viscometry are used to measure the carbonyl content and DP, respectively. The carbonyl groups are found to increase more rapidly in the recycled papers than in the non-recycled ones. On the contrary, oxidation causes a larger decrease of the DP values in the non-recycled papers, the paper made of pure cellulose being the most sensitive in terms of depolymerisation. The DP values measured for pure cellulose paper are in line with previously reported data. Moreover, in accordance with the Ekenstam equation, the plots of the reciprocal of DP as a function of oxidation time show good linear correlations for all types of paper investigated. Pseudo rate constants are thus calculated from the slopes of these plots, those of the non-recycled papers being found to be higher than those of the recycled papers. Graphic abstract

AbstractToday, the paper industry is faced with a global deficiency of raw wood materials, so alternative sources of virgin cellulose fibres are playing an important role in paper production. Agricultural countries produce large quantities of crop farming by-products such as straw, which is an interesting alternative raw material for cellulose fibres. Straw is used in many industries because of its numerous advantages: animal food industry, biofuel industry, construction industry and as artistic material. The potential use of straw production residues is of great importance in paper and printing industry. The focus of this research is on triticale straw, which was used as a non-wood fibre source for paper production. Namely, triticale straw was converted into semi-chemical pulp and was combined with recycled wood pulp in order to produce alternative laboratory papers. The usability of this kind of laboratory papers in printing industry was analysed based on line reproduction quality. This research evaluated and analysed line reproduction quality based on four line attributes: width, blurriness and raggedness. The results of this research proved that triticale pulp in laboratory papers has equal influence on line printing quality as the recycled wood pulp.

In this work, a toy was developed from bleached sulphate pulp via a moulded fibre production technique. Moulded fibre products are generally used to preserve main products from damage during transportation and stow them in a particular order. This work investigated the use of moulded fibre products in daily life as final products. Bleached softwood sulphate pulp was used for the experiments to avoid the potential hygiene problems of using recycled paper for toy production. The physical properties of different degrees of refined sulphate pulp were evaluated during toy sample production. The results indicated that toys produced with bleached softwood sulphate pulp had optimum compression strength (22 kpgf) at the 35 SR° freeness level. Produced prototypes satisfied EN 71-3:2013+A1(2014) in terms of migration element limits.

In recent years, cellulose fibre-reinforced polymer composites have been gaining a great attention in several engineering applications due to their desirable properties, which include low density, low cost, renewability and recyclability as well as good mechanical properties. Moreover, cellulose fibres are environmentally friendly, non-toxic and renewable materials. Therefore, manufacturing industries especially packaging, building construction, automotive and furniture have been encouraged to use cellulose fibres in their applications instead of the more expansive and non-renewable synthetic fibres. However, one of the major drawbacks that has limited the use of cellulose fibres as reinforcement in polymer composites is their susceptibility to moisture absorption due to the hydrophilic nature of cellulose fibres. Moisture absorption can result in a reduction of mechanical properties and dimensional stability of composites. Several studies in plant fibre reinforced polymer composites have reported an enhancement in mechanical properties, fibre-matrix interfacial bonding and fibre resistance to moisture via various chemical or physical treatments. In this project, a novel approach has been used to enhance the resistance of cellulose fibre reinforced polymer composites to water absorption and to improve the mechanical properties by introducing a nano-filler that provides good resistance to water diffusion and enhances fibrematrix interfacial bonding for better mechanical properties.In this study, epoxy eco-nanocomposites reinforced with both recycled cellulose fibres (RCF) and different nano-fillers such as nanoclay platelets (Cloisite 30B), halloysite nanotubes (HNT) and silicon carbide nanoparticles (n-SiC) were synthesized. The influence of RCF/nano-filler dispersions on physical, thermal, mechanical and fracture properties was investigated in terms of water absorption, flexural strength, flexural modulus, impact strength, fracture toughness, impact toughness and thermal stability. The effect of water soaking on the mechanical properties of composites was also investigated. Different analytical methods such as wide angle X-ray scattering (WAXS), synchrotron radiation diffraction (SRD), transmission electron microscopy (TEM), Fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to examine the nano and microstructures of these materials.First, multi layered recycled cellulose fibre (RCF) reinforced epoxy composites were fabricated with fibre loadings of 19, 28, 40, 46 and 52wt%. Results indicated that flexural strength, flexural modulus, facture toughness and impact strength increased as the fibre content increased. Water absorption and diffusion coefficient were found to increase with an increase in fibre content. Mechanical properties such as flexural strength, modulus and fracture toughness were found to decrease after water treatment due to the degradation of bonding at the fibre–matrix interfaces. The thermal stability of samples was determined using thermo-gravimetric analysis (TGA). Results indicated that the presence of cellulose fibres led to a reduction in the maximum decomposition temperature (Tmax) of epoxy. However, composites with cellulose fibre showed better thermal stability than neat epoxy at high temperature (≥ 600 oC). SEM observations showed a variety of toughness mechanisms such as crack bridging, fibre pullouts and fibre fracture and matrix cracking on the fracture surface of RCF/epoxy composites, which led to good fracture properties for samples reinforced by RCF layers.Second, epoxy-based nanocomposites reinforced with organo-clay platelets (Cloisite 30B), halloysite nanotubes (HNT) and nano-silicon carbide (n-SiC) were prepared by mixing the epoxy resin with three different filler loadings (1, 3 and 5 wt%) using a high speed mechanical mixer for 10 minutes with rotation speed of 1200 rpm. WAXS results showed that nanoclay platelets were intercalated by the epoxy resin. The d-space of the peak (001) of nanoclay increased from 1.85 to 3.4 nm after mixing with epoxy. TEM results showed a major intercalated structure with some exfoliated regions. Based on TEM results, the basal spacing of (001) varied from 2.65 to 7.98 nm. SRD results of HNT and n-SiC showed no change in the peak position after mixing with epoxy. TEM results of epoxy filled with nanoclay, HNT and n-SiC indicated that the dispersion of nanofiller was quite homogenous with some particle agglomerations that found to increase as filler content increased due to an increase in matrix viscosity. The addition of nano-fillers enhanced the mechanical properties of epoxy matrix.Maximum improvements in flexural strength, modulus and fracture toughness were achieved at 1 wt% of nano-filler loading, while the addition of 5 wt% of nano-filler displayed the maximum impact strength and toughness. The presence of nano-filler was found to have insignificant effect on the thermal stability of neat epoxy. Water absorption was found to decrease as the filler content increased. After six months of water treatment, there was a reduction in flexural strength and modulus, but an improvement in fracture toughness and impact strength. SEM results showed that nanocomposites had rougher fracture surfaces than that of neat epoxy. Several toughness mechanisms such as crack deflection, crack pinning, particle debonding, plastic void growth, plastic deformation and particle pullouts were observed.Finally, epoxy-based nanocomposites filled with nano-filler (i.e. nanoclay, HNT and n-SiC) were successfully used as a matrix for fabrication of multi-layers RCF/nano-filler reinforced epoxy econanocomposites. The presence of nano-fillers was found to have insignificant or modest effect on flexural strength, modulus and fracture toughness when compared to unfilled RCF/epoxy composites. Impact strength and impact toughness increased due to the presence of nano-fillers. The addition of nano-fillers increased the rate of the degradation by decreasing the maximum decomposition temperatures by about 8-9 oC compared to unfilled RCF/epoxy composites.However, the thermal stability of nano-filler filled RCF/epoxy eco-nanocomposites was found to increase at high temperature (≥ 500 oC). The presence of nano-fillers led to a significant decrease in maximum absorbed water compared to unfilled RCF/epoxy composites. Exposure to water for six months severely reduced the mechanical properties of wet composites when compared to dry composites. However, the addition of nano-fillers enhanced the mechanical properties of nanofiller reinforced RCF/epoxy eco-nanocomposites compared to unfilled RCF/epoxy composites in wet condition. SEM results showed that water absorption led to degradation in cellulose fibres and weakening of the bonding at fibres-matrix interfaces. Enhanced barrier and mechanical properties of nanocomposites were more pronounced for composites filled with n-SiC as compared to those filled with nanoclay platelets and halloysite nanotubes.The success in this project indicated that this approach of ‘designing for recycling’ or ‘ecodesign’ to develop environmentally friendly composite materials is achievable. Moreover, this project may provide a great momentum for a ‘cradle to grave’ approach in the eco-design of fully ‘green’ or biodegradable and environmentally friendly composite materials through the use of nanoclay and recycled cellulose fibres as reinforcement for bio-resins.

Lorsqu’une résine mélamine formaldéhyde est introduite dans un substrat cellulosique, un matériau composite est obtenu. Dans ce travail, nous montrons que les propriétés mécaniques et le comportement à l'humidité de ce composite dépendent du taux de dilution, du PH de la solution de résine et de la température de traitement utilisée. Les méthodes expérimentales utilisées sont l'analyse thermogravimétrique (ATG), l'analyse thermogravimétrique couplée IRFT, la RMN du 13C, l'analyse mécanique dynamique et l'analyse enthalpique différentielle (AED). A l'aide de l'analyse ATG utilisée en mode isotherme, nous avons montré que les cinétiques de dégradation des celluloses recyclées sont d'ordre 1. Ce résultat nous a autorisés à utiliser le modèle cinétique de Broido (mode dynamique) et ainsi à trouver une méthode qui permet la quantification des constituants des celluloses de récupération en particulier les quantités relatives en pâte mécanique et chimique. A l'aide de l'ATG couplée IRFT, l'ATG en mode isotherme et en mode dynamique et l'AED, nous avons montré que les réactions d'auto condensation de la résine sont accélérées en PH acide lorsque cette résine est introduite dans la matrice cellulosique. Les mesures viscoélastiques montrent que des réactions de co-condensation peuvent avoir lieu pour des recuits à haute température lorsque le PH est neutre ou basique, tandis que pour les systèmes à PH acide les réactions d'auto condensation restent majoritaires. Enfin, l'étude en absorption d'eau sur les composites résine/cellulose recyclée (PH=7) montre un double mode d'absorption, du type Langmuir et Flory Huggins, dépendant du taux d'humidité relative. En présence de la résine mélamine formaldéhyde le comportement à l'humidité du composite se rapproche de celui d'un polymère dense.

En réponse à une forte croissance démographique mondiale, et notamment africaine, il est nécessaire d’anticiper les besoins de la population en terme de bâtiment. Il s’agit alors de développer des matériaux alternatifs présentant des performances multi-physiques adéquates tout en ayant un faible impact sur l’environnement. Ce travail porte sur l’élaboration et la caractérisation de composites utilisables comme produits constructifs de partition (cloison, faux plafonds). La sélection des matières premières intègre des critères de développement durable, en considérant leur disponibilité locale mais également leur empreinte en terme d’épuisement des ressources (matériaux recyclés ou bio-sourcés). Les liants utilisés sont le plâtre, l’amidon de pomme de terre et l’amidon de manioc. Les charges sont la fibre de bois, la ouate de cellulose et les granules de papiers, pour une valorisation originale en matériau de construction. Les performances des composites développés sont évaluées d’un point de vue mécanique, hygrique, thermique et en terme de résistance au feu. Ces travaux ont montré la faisabilité et l’intérêt de tels composites. Ceux-ci peuvent notamment être utilisés pour leur qualité de régulateur hygrique et de correcteur thermique
Due to strong global population growth, and particularly African, the population’s needs in terms of building have to be anticipated. The aim is to develop alternative materials with adequate multiphysical performances and low impact on the environment. This work investigates the elaboration and characterization of composites to be used as constructive partition products (partitions, false ceilings). The selection of raw materials takes into account sustainable development criteria, considering both the local availability of materials and their footprint in terms of resource depletion (recycled or bio-sourced materials). The binders used are plaster, potato starch and cassava starch. The loads are wood fiber, cellulose wadding and paper granules, for an original valorisation in building material. The performances of the developed composites are evaluated from a mechanical, hygric, thermal and fire resistance point of view. This work has shown the feasibility and the interest of such composites. These can in particular be used for their quality of hygric regulator and thermal corrector

O objetivo do presente estudo foi agregar valor a fibras de sisal, a dois dos componentes principais de fibras lignocelulósicas (celulose e lignina) e a PET reciclado, via produção de materiais com elevado valor agregado. Neste contexto, foram investigadas condições que levassem a mats constituídos por nanofibras/fibras ultrafinas, alinhadas (coletor rotativo) e não alinhadas (coletor estático), a partir da eletrofiação de soluções contendo essas matérias-primas, combinadas ou não [PET/sisal, PET/celulose e/ou lignina, PET/CNC (combinado ou não com OM)], em TFA. Parâmetros de solução, como razão PET/componente da biomassa e tempo de dissolução, foram diversificados, assim como parâmetros de processo (taxa de vazão da solução e velocidade de rotação do coletor utilizado, por exemplo). Os resultados de DMA indicaram a influência positiva do alinhamento das fibras nos superiores valores de E\' [tanto para os mats de PET/sisal, quanto para os mats de PET/celulose e/ou lignina e PET/CNC (combinado ou não com OM)] e também foi possível observar que não houve uma influência significativa desse alinhamento na Tg do PET nestes materiais. Como exemplo, o valor de E\' (a 30 °C) para o mat de fibras alinhadas, com razão de sisal/PET = 0,40 (S/PET0,40 – A dir), caracterizado na direção preferencial de alinhamento das fibras, foi superior (765,0 MPa), em comparação ao valor apresentado pelo mat de fibras orientadas aleatoriamente, de composição correspondente, S/PET0,40 (E’ = 358,0 ± 1,5 MPa). A molhabilidade dos mats foi intrinsicamente dependente da razão fibra de sisal/PET e variou de altamente hidrofóbico (PETref, ACA de 134°), a super hidrofílico (S/PET0,40, ACA de 0°). Observou-se que, as principais influências da presença de lignina foram na morfologia achatada das fibras e no aumento do alongamento na ruptura dos materiais, de aproximadamente 90%, comparativamente a PETref. A presença da celulose resultou principalmente em um elevado diâmetro médio das fibras (valores de até 365,9 ± 139,7 nm) e módulo de Young dos materiais (com valores de até 360,4 ± 41,5 MPa), comparativamente ao apresentado pelos mats contendo PET e este polímero combinado com lignina. Os resultados mostraram que os CNCs exerceram uma ação efetiva como agentes de reforço, principalmente nos mats constituídos por fibras orientadas aleatoriamente de PET, considerando as propriedades mecânicas apresentadas por esses materiais (como resistência à ruptura de 4,6 ± 0,5 MPa), em comparação ao mat PETref (resistência à ruptura = 1,8 ± 0,2 MPa). O OM atuou como agente compatibilizante entre o PET reciclado e os CNCs, principalmente com relação ao superior valor de módulo de Young de PET/OM/CNC (354,2 ± 46,1 MPa), em comparação ao valor apresentado por PET/CNC (19,9 ± 3,9 MPa). Assim, os objetivos do presente trabalho foram atingidos com a preparação via eletrofiação, até onde se tem conhecimento, pela primeira vez, de mats de fibras alinhadas e não alinhadas baseadas em biomassa lignocelulósica nativa e dois de seus principais constituintes (celulose e lignina). Os materiais preparados apresentam uma vasta gama de possíveis aplicações, como sistemas de filtração de ar, por exemplo.
The aim of the present investigation was to add value to sisal fibers, to two of the major components of lignocellulosic fibers (cellulose and lignin) and recycled PET via preparation of materials with high added value. In this context, conditions that lead to mats of nanofibers and ultrathin fibers were investigated, aligned (rotating drum collector) and nonaligned (stationary collector), via electrospinning of solutions containing these raw materials, combined or not {PET/sisal fiber, PET/cellulose and/or lignin, PET/CNC [combined or not with castor oil (CO)]} in TFA. Solution parameters such as the ratio of PET/biomass component and dissolution times were diverse, as well as process parameters (e.g. solution flow rate and rotational speed of the collector). The DMA results indicated the positive influence of fiber alignment on the higher storage modulus – E’ [for mats of PET/sisal, PET/cellulose and/or lignin and PET/CNC (combined or not with CO)] and it was also possible to observe no significant influence of fiber alignment on the Tg of PET for these mats. The value of E’ (at 30 °C) for the aligned fibers mat with sisal/PET ratio = 0.40 (S/PET0.40 - A dir), characterized in the preferred direction of fiber alignment, was higher (765.0 MPa) when compared to the value presented by the randomly oriented fibers mat of the corresponding composition, S/PET0.40 (E’ = 358.0 ± 1.5 MPa). The wettability of the mats was intrinsically dependent on the sisal/PET fiber ratio and ranged from highly hydrophobic (PETref, ACA of 134°) to super hydrophilic (S/PET0.40, ACA of 0°). It was observed that the main influences of the presence of lignin was on the flat fibers morphology and on the increase of the elongation-at-break of the materials of approximately 90% compared to PETref. The presence of cellulose resulted mainly in a high average fiber diameter (values up to 365.9 ± 139.7 nm) and elastic modulus of the materials (values up to 360.4 ± 41.5 MPa) compared to the ones presented by mats containing PET and by this polymer combined with lignin. The results showed that the CNCs were efficient as reinforcing agents, especially in the mats composed of randomly oriented fibers of PET, considering the mechanical properties presented by these materials (such as ultimate tensile strength of 4.6 ± 0.5 MPa) compared to PETref mat (ultimate tensile strength = 1.8 ± 0.2 MPa). CO acted as a compatibilizing agent between recycled PET and CNCs, mainly regarding the superior elastic modulus value of PET/OM/CNC (354.2 ± 46.1 MPa) compared to PET/CNC mat (19.9 ± 3.9 MPa). Therefore, the goals of the present study were reached for the first time with the preparation of aligned and nonaligned fiber mats based on native lignocellulosic biomass and two of its main constituents (cellulose and lignin), to the best of our knowledge. The prepared materials have a wide range of possible applications, such as air filtration systems, for example.

Nowadays, construction sector is focusing in developing sustainable, green and eco-friendly building materials. Natural fibre is growingly being used in composite materials. This paper provides utilization of cellulose fibres as reinforcing agent into cement composites/plasters. Provided cellulosic fibres coming from various sources as bleached wood pulp and recycled waste paper fibres. Differences between cellulosic fibres are given by their physical characterization, chemical composition and SEM micrographs. Physical and mechanical properties of fibre-cement composites with fibre contents 0.2; 0.3and 0.5% by weight of filler and binder were investigated. Reference sample without fibres was also produced. The aim of this work is to investigate the effects of cellulose fibres on the final properties (density, water absorbability, coefficient of thermal conductivity and compressive strength) of the fibrecement plasters after 28 days of hardening. Testing of plasters with varying amount of cellulose fibres (0.2, 0.3 and 0.5 wt. %) has shown that the resulting physical and mechanical properties depend on the amount, the nature and structure of the used fibres. Linear dependences of compressive strength and thermal conductivity on density for plasters with cellulosic fibres adding were observed.

Traditional papermaking is based on the use of an aqueous suspension consisting of cellulose fibres obtained by processing wood, non-wood plants or waste paper. With growing environmental concerns regarding deforestation and CO2 production, the paper industry has been always looking for new sources of non-wood pulp that would produce papers of similar quality to those made from wood pulp. Cereal straw from wheat, barley or triticale crops that remains on fields as a residue after grain harvesting has proven to be a good substitute for virgin wood fibres needed in the production of recycled paper. In this study, the quality of printed text on recycled paper with added straw pulp is evaluated mainly based on the line and edge characteristics of the printed letters. For this purpose, three types of laboratory paper substrates were first prepared using recycled wood pulp with the addition of 30% wheat, barley, or triticale straw pulp. The same letter pattern was printed with black ink on each paper substrate at a standard size of 12 pt with two common typefaces: Arial and Times New Roman. The quality of the printed letters was assessed through the measured print quality parameters such as blurriness, raggedness, fill and contrast. The resulting measurements were compared with the results obtained on the reference and control samples made exclusively from recycled wood pulp as a substrate from laboratory and commercial production. In terms of fill and contrast values, the uniformity of lines printed on the recycled papers with added straw pulp is the same or very similar to the reference and control papers. Letters printed in Arial (sans-serif) typeface show slightly better reproduction quality than letters printed in Times New Roman (serif) typeface. The measured parameters blurriness and raggedness of all laboratory-made paper substrates (with and without straw pulp) had similar values between 0.17 mm and 0.20 mm, resulting in a very similar reproduction quality compared to the reference paper substrate.

Due to depleting natural resources, it is necessary to develop eco-composite materials that are fabricated from sustainable and inexpensive materials such as recycled paper or cellulose-based materials. Such materials are required to meet the mechanical performance at par with traditional materials. The main aim of this study was to investigate the mechanical performance of a composite material fabricated from paper pulp and polyvinyl acetate (wood glue). It is expected that a high strength composite material may be achieved by varying the amount of paper-pulp fiber fraction from 7.5%, 10%, 20%, 30%, 40%, 50% to 60% weight. A tensile test was conducted and it was found that an increase in fiber content on the fabricated composite resulted in an increase in ultimate tensile strength and a decrease in corresponding strain. Furthermore, the material becomes more brittle at higher fiber content and conversely, more ductile at lower fiber content. The ultimate tensile strength was found to be 7.69 MPa at 60% w.t fiber and the minimum tensile strength was 0.12 MPa at 0% w.t fiber. There were no signs of fiber content limit observed in the obtained results. It was concluded that a composite of moderate strength was produced and future work is required in order to fully understand how the composite behaves at different loading conditions. However, an optimum fiber content limit will have to be determined.

Nowadays, various materials are being analyzed as a possible component of pavement structure with the goal of using sustainable building materials and protecting the environment. Waste and recycled materials are added to pavement layers in order to improve it. Also, the possibility of using natural, renewable materials by incorporating them into existing standard materials is been examined. Cement-stabilized base course increases load-carrying capacity of the pavement but is prone to cracking which causes reflection cracks in an asphalt surface. Reinforcement of cement-stabilized base course can be achieved by the addition of fibers. Fibers added to the cement stabilization tend to prevent or delay the crack initiation and propagation by redistributing the resulting stresses. Considering the research conducted to-date and the need to use sustainable materials in combination with cement stabilization, some attempts are being made to achieve improvements of this pavement layer. Natural fibers are locally available, economical, renewable and degradable, and can be used as reinforcement. In the Mediterranean area, a possible source of cellulose fibers is found in the wild plant named Spanish Broom (Spartium junceum L). This paper offers an overview of research studies about fiber reinforcement of cement-stabilized base course. It also presents current research on Spanish Broom fibers in cement composites, as well as possible ways of obtaining and treating fibers. Based on the results of this research, a method for obtaining the fibers can be selected which might improve the mechanical properties of cement-stabilized course.

To maintain a circular economy and better sustainability, it is important to minimize the use of synthetic polymers. Nowadays, agricultural and industrial wastes or by-products are increasingly being used as raw materials in industrial processes. It has been determined that agro-industrial wastes have a high potential of cellulose fibers, which makes them an excellent resource for paper production. Recently, potential resources from non-wood raw materials for paper production, as well as cheap raw materials, have become the interest of various researchers. Since our main focus is on the study of thermochromic inks (TC) and the influence of substrate characteristics on their dynamic color change, this paper will examine the possibilities of a commercially available offset TC ink printed on several environmental friendly pressure sensitive labels (PSL) facestock compared to commonly use in PSL production. For the purpose of this study, a commercially available TC ink with an activation temperature (TA) of 29°C was used. The effect of color change, from blue to colorless, was measured through one heating and cooling cycle at several selected temperatures at six different PSL materials. Three fiber-based facestock of PSL used in this research are produced with 15% agroindustrial byproducts, 40% post-consumer recycled paper and 45% virgin wood pulp to form a high-quality natural paper. In addition, one material made from biogenic polymers facestock and two materials commonly used in labels production were used as well. The results of this research show that TC ink printed on alternative materials has a similar trend of color change and may be a good choice. Also, the influence of the color of fiber-based paper substrates on the change of TC color was noticed, which indicates the importance of colorimetric analysis of paper and TC ink before their printing.