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The primary aim of this research was to explore the feasibility of producing environmentally friendly composite materials by employing diverse hybrid matrices consisting of dammar natural resin, supplemented with small proportions of two synthetic resins: one epoxy and the other acrylic. A blend of paper and chicken feathers served as the reinforcing elements. The fabrication of these composite materials utilized a hand layup technique. Targeted for applications in the furniture industry or interior design, their mechanical properties were assessed through various tests. Specimens were obtained from the manufactured samples and subjected to evaluations for tensile strength, compression, flexure, vibrations, Shore hardness, and water absorption. Results indicated that irrespective of the testing method employed, the mechanical strength properties exhibited a decline with an increase in the percentage of dammar in the hybrid resins, whereas the elasticity properties demonstrated an increase with this percentage.

The primary aim of this research was to explore the feasibility of producing environmentally friendly composite materials by employing diverse hybrid matrices consisting of dammar natural resin, supplemented with small proportions of two synthetic resins: one epoxy and the other acrylic. A blend of paper and chicken feathers served as the reinforcing elements. The fabrication of these composite materials utilized a hand layup technique. Targeted for applications in the furniture industry or interior design, their mechanical properties were assessed through various tests. Specimens were obtained from the manufactured samples and subjected to evaluations for tensile strength, compression, flexure, vibrations, Shore hardness, and water absorption. Results indicated that irrespective of the testing method employed, the mechanical strength properties exhibited a decline with an increase in the percentage of dammar in the hybrid resins, whereas the elasticity properties demonstrated an increase with this percentage. [ABSTRACT FROM AUTHOR]

Abstract The incorporation of natural fibers into polymer matrices poses challenges due to physicochemical incompatibility, which is typically addressed through precursor modification or the use of compatibilizers. Here, we introduce a novel type of composite that overcomes this challenge by utilizing a network of fine, porous cellulosic sheets inter-diffused with a commercial paraffin films. This approach physically adheres the fiber network to the matrix, preserving its structure. Microscopy images confirm the formation of the proposed microstructure, and mechanical testing reveals a gradual increase in modulus and strength with the incorporation of cellulose. The maximum incorporation achieved was 7.6% (w/w) of cellulosic fibers, resulting in a 167% increase (1.67 times improved) in composite stiffness. Moreover, these composites exhibit ductility, with an average deformation of 410 ± 38%, corresponding to 20% reduction in relation to pure matrix. Our findings demonstrate the potential of this approach for developing sustainable materials with improved mechanical properties.

In this review, we summarize the recent progress in thermal conductivity analysis of nanocellulose materials called cellulose nanopapers, and compare them with polymeric materials, including neat polymers, composites, and traditional paper. It is important to individually measure the in-plane and through-plane heat-conducting properties of two-dimensional planar materials, so steady-state and non-equilibrium methods, in particular the laser spot periodic heating radiation thermometry method, are reviewed. The structural dependency of cellulose nanopaper on thermal conduction is described in terms of the crystallite size effect, fibre orientation, and interfacial thermal resistance between fibres and small pores. The novel applications of cellulose as thermally conductive transparent materials and thermal-guiding materials are also discussed.

Polyurethane elastomer (PUE) composites were synthesized with a low additive content of waste natural cellulosic fibers from office paper. A new technology combining prepolymer method with physical blending and modification was adopted. The results showed that cellulosic fibers were covalently bonded to polyurethane molecular chains and served as a cross-linking agent making the degree of phase separation decrease. Even so, the lowest additive content of cellulosic fibers (1 wt%) in this work could make polyurethane still hold a certain degree of phase separation. Besides, thermal stability of polyurethane was improved from 288 to around 300 °C even at the low cellulosic fibers content. PUE with 3% cellulosic fibers had the better interfacial compatibility between cellulosic fibers and polyurethane causing the greater thermal reinforcement. PUE with 4% and 5% cellulosic fibers had the worse interfacial compatibility generating the better damping capacity indicating that cellulosic fibers could improve damping performance of polyurethane, especially polyurethane with 5 wt% fibers. It meant that cellulosic fibers had a potential application in damping materials. [ABSTRACT FROM AUTHOR]

ABSTRACT: Conventional cellulosic paper, rendered electro‐conductive, may hold considerable promise for diversified applications in such areas as electro‐magnetic interference shielding and energy storage. Here, an electro‐conductive cellulosic paper was prepared by surface application of multi‐walled carbon nanotubes (MWCNTs)/polyaniline (PANI) nanocomposites onto a conventional base paper. MWCNTs/PANI nanocomposites were prepared by in situ polymerization of aniline with different contents of MWCNTs and used as electro‐conductive filler for the fabrication of electro‐conductive surface‐coated paper. The achieved MWCNTs/PANI nanocomposites exhibited a core‐shell structure, as evidenced by TEM. Effects of feeding ratios of MWCNTs on the rheological behavior of nanocomposite coatings, as well as the mechanical properties and electrical conductivity of surface‐coated paper were studied. Results revealed that the rheological behavior of the nanocomposite coatings showed strong dependence on the MWCNTs content. Moreover, both the electro‐conductivity and mechanical properties of surface‐coated paper were improved as a function of surface application of MWCNTs/PANI nanocomposites, particularly, in presence of an optimum content of MWCNTs. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46329. [ABSTRACT FROM AUTHOR]

In this review, we summarize the recent progress in thermal conductivity analysis of nanocellulose materials called cellulose nanopapers, and compare them with polymeric materials, including neat polymers, composites, and traditional paper. It is important to individually measure the in-plane and through-plane heat-conducting properties of two-dimensional planar materials, so steady-state and non-equilibrium methods, in particular the laser spot periodic heating radiation thermometry method, are reviewed. The structural dependency of cellulose nanopaper on thermal conduction is described in terms of the crystallite size effect, fibre orientation, and interfacial thermal resistance between fibres and small pores. The novel applications of cellulose as thermally conductive transparent materials and thermal-guiding materials are also discussed. [ABSTRACT FROM AUTHOR]

This review describes the state-of-the-art of material derived from the forest sector with respect to its potential for use in the packaging industry. Some innovative approaches are highlighted. The aim is to cover recent developments and key challenges for successful introduction of renewable materials in the packaging market. The covered subjects are renewable fibers and bio-based polymers for use in bioplastics or as coatings for paper-based packaging materials. Current market sizes and forecasts are also presented. Competitive mechanical, thermal, and barrier properties along with material availability and ease of processing are identified as fundamental issues for sustainable utilization of renewable materials.

ABSTRACT Kraft pulp fibers were used as substrates for the grafting of poly(ε-caprolactone) (PCL) from available hydroxyl groups through ring-opening polymerization, targeting three different chain lengths (degree of polymerization): 120, 240, and 480. In a paper-making process, paper-sheet biocomposites composed of grafted fibers and neat pulp fibers were prepared. The paper sheets possessed both the appearance and the tactility of ordinary paper sheets. Additionally, the sheets were homogenous, suggesting that PCL-grafted fibers and neat fibers were compatible, as demonstrated by both Fourier transform infrared spectroscopy microscopy and through dye-labeling of the PCL-grafted fibers. Finally, it was shown that the paper-sheet biocomposites could be hot-pressed into laminate structures without the addition of any matrix polymer; the adhesive joint produced could even be stronger than the papers themselves. This apparent and sufficient adhesion between the layers was thought to be due to chain entanglements and/or co-crystallization of adjacent grafted PCL chains within the different paper sheets. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42039. [ABSTRACT FROM AUTHOR]

ABSTRACT A novel strategy via paper as an effective substrate has been introduced as a thermoelectric material in this work. Free-standing poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/paper composite films are conveniently prepared by a one-step method of directly writing PEDOT:PSS solution on paper, making the process simple, rapid, and facile. The free-standing composite films display excellent flexibility, light weight, soaking stability in water, and great potential in large-scale production. Improved thermoelectric properties are obtained in PEDOT:PSS/paper composite films, owing to the simultaneously enhanced Seebeck coefficient (30.6 μV K−1) and electrical conductivity, and a low thermal conductivity (0.16 W m−1 K−1) compared with pristine PEDOT:PSS films. The results indicate that paper as an effective substrate is suitable for the preparation of high-performance and flexible thermoelectric materials. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 737-742 [ABSTRACT FROM AUTHOR]

ABSTRACT To improve the paper properties of the poly(1,3,4-oxadiazoles) (POD), the POD pulps were prepared by prechemical and mechanical methods to increase their polarity, contact area, and interaction. The fibrillated degree of the staple fibers was evaluated by the Canadian Standard Freeness and the specific surface area, while the surface free energy was calculated by the Micro-wilhelmy method. Meanwhile, the functional groups and compositions on the surface of the POD fibers were confirmed by the FTIR-ATR and the X-ray photoelectron spectroscopy, and the surface morphological structure and the crystalline structure of the POD fibers were observed by the fiber analyzer, scanning electron microscope, and Wide-angle X-ray diffraction, respectively. It was found that the pronounced abrasive and distinctive grooves were formed on the surface of the POD fibers after prechemical and mechanical treatment. The surface free energy of POD fibers increased 8.41%, and the polar part increased by 32.10% after treatment. It was confirmed that the polar functional groups and fibril were formed after chemical and mechanical treatment, so the interaction of the POD fibers was highly enhanced, and as a result the apparent density, tensile strength, fold endurance, and tear strength of the paper formed by those treated fibers were all improved apparently. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39818. [ABSTRACT FROM AUTHOR]

High strength and low gas permeability cellulosic composites were produced using the papermaking technology with a commercial microfibrillated cellulose (MFC). The effect of blending MFC with hardwood fibers was compared to the direct refining of the fibers with and without polyamideamine-epichlorohydrin (PAE) addition. The addition of MFC, free or tethered, to pulp fibers combined with PAE can increase the dry strength and wet strength of cellulosic materials by an order of magnitude. Air permeability of the composites decreases by up to orders four of magnitude with MFC addition. The hypothesis that refining wood fibers can produce tethered MFC which provides equivalent strength properties but significant drainage benefits was proven. Furthermore, major benefits in paper formation uniformity (fiber distribution homogeneity) were achieved with refined fibers. [ABSTRACT FROM AUTHOR]

This review describes the state-of-the-art of material derived from the forest sector with respect to its potential for use in the packaging industry. Some innovative approaches are highlighted. The aim is to cover recent developments and key challenges for successful introduction of renewable materials in the packaging market. The covered subjects are renewable fibers and bio-based polymers for use in bioplastics or as coatings for paper-based packaging materials. Current market sizes and forecasts are also presented. Competitive mechanical, thermal, and barrier properties along with material availability and ease of processing are identified as fundamental issues for sustainable utilization of renewable materials. [ABSTRACT FROM AUTHOR]

The current work analyses the potential usage of vegetal fibers environmentally sound based materials. The paper approaches the main applications of vegetal fiber sustainable integration into products. The origin of vegetal fibers and the degree of processing affect their chemical composition and furthermore its performance in future application. Some aspects on the structure and chemical composition of vegetal fibers are presented. The usage of vegetal fibers for manufacturing on paper and fiber containing composites is considered. Paper is the most important fiber based material and non woods as sustainable virgin fiber sources are discussed. Besides papermaking, vegetal fibers are potentially usable as reinforcements in cement and gypsum fiber composites. Some considerations regarding manufacturing processes and factors affecting mechanical properties of composites are presented. Other usages of vegetal fiber involve the manufacturing of polymer matrix composites. The chemical ways to improve interfacial linking between vegetal fibers and polymeric matrix are shortly underlined. Aspects regarding the environmental impact and life cycle assessment of the vegetal fiber based materials were taken into consideration. [ABSTRACT FROM AUTHOR]

Abstract: This paper highlights an innovative model of waste management combined with poverty reduction, which has been developed by the organisation Waste for Life (wasteforlife.org) – a network of academics, students, practitioners and on the ground cooperative partners in low income communities. The Waste for Life teams work with local cooperatives to create waste-based composites, which may be sold in local markets, thereby creating an income stream. The application of this model to the context of cartoneros (waste picker) cooperatives in Buenos Aires, Argentina, reveals that viable products can be made from paper and plastic waste, with low-impact material preparation that circumvents the need for chemically intensive, polluting and mechanically degrading procedures, preserving recycled fibre integrity. Tests on material samples indicate mechanical properties comparable to products made with more complex processing. The production model is based on the philosophy that not only the waste materials, but also the production equipment should be locally sourced and manufactured and products created to suit local markets. A simple reproducible model has been developed for the local manufacture of composites from waste, which can provide an income source for waste pickers as well as providing an innovative waste management solution. [Copyright &y& Elsevier]

Abstract: A series of wood-fibre mats was investigated using high-resolution phase-contrast microtomography at the beamline ID 19 of the European Synchrotron Radiation Facility in Grenoble, France. A method for data reduction to quantify the degree of fibre–fibre contact has been derived. The degree of fibre–fibre contact and bonding plays a fundamental role in the mechanical properties of cellulose-fibre mats, paper materials and cellulose-fibre composites. The proposed computerised automated method consists of two parts. First, fibre lumens are segmented using a watershed based method. This information is then used to identify fibre–fibre contacts in projections along the z-axis of the material. The method is tested on microtomographic images of mats made of wood pulp fibres, and is shown to successfully detect differences in the amount of fibre–fibre contact between samples. The degree of fibre–fibre contact correlates well with measured out-of-plane strength of the fibrous material. [Copyright &y& Elsevier]

Abstract: Platinum/aluminum oxide (Pt/Al2O3) catalyst powders were successfully fabricated to give paper-like composites using ceramic fibers by a papermaking technique. As-prepared composites, called paper-structured catalysts, possessed a fiber-network microstructure on which the Pt/Al2O3 powders were scattered. The paper-structured catalysts were subjected to a catalytic reduction process of nitrogen oxides (), and demonstrated a higher performance than the original Pt/Al2O3 powders and a commercial honeycomb catalyst. A simple mixture of catalyst powders and inorganic fibers was not effective, suggesting that the characteristic porous microstructure (average pore size: ca. porosity: ca. 70%) in the paper-structured catalyst possibly contributed to the efficient reduction. Besides, the paper-structured catalyst exhibited a quick response in the catalytic reduction at a rapidly increasing reaction temperature as compared to the honeycomb catalyst. The paper composite is flexible, lightweight and easy to handle; thus the paper-structured catalyst is expected to be a promising catalytic material for exhaust gas purification. [Copyright &y& Elsevier]

Abstract: Enzymatic bonding methods, based on laccase or peroxidase enzymes, for lignocellulosic products such as medium-density fiberboard and particleboard are discussed with reference to the increasing costs of presently used petroleum-based adhesives and the health concerns associated with formaldehyde emissions from current composite products. One approach is to improve the self-bonding properties of the particles by oxidation of their surface lignin before they are fabricated into boards. Another method involves using enzymatically pre-treated lignins as adhesives for boards and laminates. The application of this technology to achieve wet strength characteristics in paper is also reviewed. [Copyright &y& Elsevier]

The effects of surface treatment of paper sludge (PS) with acrylic acid (esterification) and acetic acid (acetylation) on torque, stabilization torque, mechanical properties, water absorption, morphology, and thermal properties of PP/EPDM/PS composites were studied. It was found that esterified and acetylated composites exhibit higher stabilization torque than untreated composites. The esterification and acetylation treatment have improved the tensile strength, elongation at break, and Young's modulus but have reduced the water absorption of composites. The scanning electron microscopy (SEM) study of the tensile fracture surface of the esterified and acetylated composites indicates that the presence of acrylic acid and acetic acid increased the interfacial interaction between paper sludge and PP/EPDM matrix. The esterification and acetylation treatment also increase the thermal stability and crystallization of PP/EPDM/PS composites. It was found that paper sludge acts as a nucleation agent in the presence of acrylic acid and acetic acid. [ABSTRACT FROM AUTHOR]