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As is well known, Laser print paper is usually produced with high‐quality chemical wood pulp. The laser print waste paper fiber (LPWF) is a high‐quality secondary fiber, and the research and development of high‐value utilization technology for laser print waste paper has attracted much attention in the field of renewable resource recycling. In this study, LPWF was used to reinforce poly(lactic acid) (PLA) composites in the field, and the composites were modified with bioenzyme, cationic polyacrylamide (CPAM), and nano‐silicon carbide (Nano‐SiC) to enhance the interfacial compatibility of LPWF/PLA composites. The study systematically investigated the effects of various modification methods on the characteristics and degradability of composites made from laser print waste paper fiber reinforced PLA resin matrix. The results showed that the mechanical properties of the composites treated with CPAM and Nano‐SiC were significantly improved, with tensile strengths of 54.3 and 59.5 MPa, and flexural strengths of 85.1 and 91.5 MPa, respectively, and the water absorption of the composites was reduced after the modification treatment, while the thermal stability was improved. The degradation performance of the composites in various water environments indicated that the inclusion of LPWF accelerated the water degradation rate of the composites, with the maximum degradation rate of the composite reaching 1.26% in 30 days. Highlights: Laser print waste paper is an excellent quality recyclable fiber resource.Four modifiers were used to modify LPWF/PLA composites.Characteristics and degradability of the composites were investigated.Significantly improved properties of CPAM and Nano‐SiC modified composites.The degradation rate of composites is increased by the addition of LPWF. [ABSTRACT FROM AUTHOR]

This study investigated converting abundant paper mill waste, de‐inked paper sludge (DPS), into value‐added medium‐density fiberboard (MDF) panels. The objective was to repurpose this solid waste into a valuable material that aligns with the principles of a circular economy. Previous research has examined the addition of paper sludge to wood composites, but there is limited information on the specific incorporation of DPS into MDF production. This investigation offers new insights into this application. MDF panels were manufactured using hardwood fibers, with varying levels of urea‐formaldehyde resin (10% and 12% by weight) and different loadings of DPS (ranging from 0% to 50% by weight). X‐ray diffraction analysis revealed the presence of defective DPS fiber crystals. Contact angle measurements confirmed that DPS had poor wettability, corresponding to increased water absorption. As more DPS was incorporated, the mechanical properties of the panels progressively weakened due to defective fibers and poor adhesion between the fibers and the matrix. This was evident in scanning electron microscopy micrographs, which showed an escalation in interfacial flaws. Increasing the resin dosage noticeably improved the internal bond strength and reduced moisture uptake across all levels of DPS. However, at a DPS loading of 50%, the properties of the panels deteriorated by 36%–57% compared to the control MDF. Additionally, thickness swelling and water absorption increased significantly with higher DPS content, primarily due to the hydrophilic nature of the fibers. Based on optimization, it was determined that a DPS loading of 20% with a resin content of 12% provided the best balance between performance, waste utilization, cost, and moisture resistance. The reuse of abundant paper sludge supports the goals of a circular economy. However, strategies are required to tailor the processing methods and enable higher levels of recycled material without excessively compromising the key attributes of the product. Further research should focus on enhancing the quality of DPS and its compatibility with wood fibers and resin to enhance the performance of the composite material. Highlights: DPS from recycled paper mill assessed for MDF production with wood fibers and resinIncreasing DPS loading caused reductions in strength and adhesion of panelsWater absorption and thickness swelling markedly rose with more DPS additionIt was attributed to hydrophilic fibers and disrupted fiber‐matrix bondingOptimal formulation was 20% DPS loading and 12% resin content, balancing performance, waste utilization, and cost. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) is a conventional packaging material. Its modification has attracted immense attention in the industry and academia. Here, office waste paper, white cardboard waste, and waste corrugated paper were first employed as raw materials for cellulose nanocrystal (CNC) extraction by acid hydrolysis. Thereafter, CNC/PET composite films with various CNC additions were prepared via a self‐assembly technique. The results revealed that the CNCs formed a self‐assembled film on the PET surface via the synergistic effect of the complex interactions among the CNCs as well as between the CNCs and PET. Moreover, the CNCs improved the barrier property of PET and decreased the oxygen and water vapor transmittances of CNC/PET by 30.7% and 21.7%, respectively. Additionally, the coating of the PET surface with 0.2 wt.% CNCs extracted from the waste paper decreased the surface wettability of PET, exhibiting application potentials in the hydrophobic modification of polymers. This study realized waste paper recycling and provided a basis for constructing self‐assembled functional films on PET surfaces. The findings and insights of this study could exhibit application potentials in the fields of waste recycling and packaging materials. Highlights: A functional cellulose nanocrystal (CNC) film is prepared from waste paper.Self‐assembled CNC is coated on a PET surface to form a CNC/PET composite film.The synergistic interactions among CNCs and between CNC and PET modified PET.The low addition of CNCs realized the efficiency modification of PET.The study achieves waste paper recycling and high‐value utilization. [ABSTRACT FROM AUTHOR]

Nanocellulose extraction from lignocellulosic materials is a highly chemical and energy‐intensive process as it requires the removal of lignin and hemicellulose. Writing paper is one of the processed materials that could be used as a raw material for the extraction of nanocellulose. In this work, cellulose nanofibers (CNFs) were synthesized from paper waste using TEMPO‐oxidation followed by high‐shear microfluidization. Scanning electron microscopy and atomic force microscopy confirmed the diameter of fibers in the nano‐range and a consistent zeta potential confirmed the stability of CNF suspension in water over a long time frame. Characterization of the CNFs using Fourier transform infrared spectroscopy indicated the presence of a carbonyl group due to the oxidation process. Thermogravimetric analysis and x‐ray diffraction revealed lower thermal stability and reduction in the crystallinity index of CNFs, as compared to pulp fibers. The obtained CNFs were used successfully as the sole binding agent in the preparation of fiberboards and also utilized as a reinforcing agent for polyvinyl acetate (PVAc) adhesive in the preparation of laminated veneer lumber (LVLs). The addition of CNFs in PVAc improved the glue shear strength indicating superior bonding characteristics and also increased the water resistance of the LVLs. Highlights: This work focused on cellulose nanofibers (CNFs) extraction from waste paperObtained CNFs form stable water suspension and have a diameter of less than 15 nmThermal stability and crystallinity index reduced after conversion to nanofibersCNFs form a complex network and act as a sole binder to make fiberboardsCNFs were utilized as a reinforcing agent for PVAc in preparation of LVLs [ABSTRACT FROM AUTHOR]

Highlights The graphene electrothermal de‐icing system has attracted extensive attention due to its efficient anti‐icing/de‐icing ability, but the interlayer properties of the heating layer are relatively weak. Currently, there is limited research on the interlayer properties of multilayer complex structures of graphene papers (GPs)/glass fibers (GFs)/epoxy (EP) reinforced resin composites (GPs/GE). In this study, a GPs/GE sandwich structure was prepared using a vacuum bag molding, and the effects of fabric structure and core material on the interlaminar mechanical properties of the sandwich structure were studied using the T‐peel test. A multiscale morphological investigation was conducted to analyze the crack growth and failure modes in the sandwich structures. The results indicated that the fabric structure caused anisotropy in the interlaminar peel performance of the composite material. The weft fibers contributed to inhibiting crack propagation. The GPs/GE achieved the highest peel strength of 0.533 N/mm under the (0,90)s layup configuration. The peel performance of GPs/GE was only 5.5% lower than that of conventional metal sandwich composite materials. In addition, GPs demonstrated the advantage of being lighter and thinner within the composite material. Through co‐curing bonding, the T‐peel performance of the GPs/GE sandwich structure was improved by 72.2%, thereby solving the problem of weak interlayer properties of the heating layer. Damage and failure mechanisms at different GPS/GE interfaces were explained. The fabric structure resulted in anisotropy in the peel performance of GPs/GE. The area ratio and arrangement of GPs influenced the stress distribution. GPs/GE exhibited excellent interlayer properties after co‐curing bonding. [ABSTRACT FROM AUTHOR]

Highlights To tackle the ease of aggregation issue of highly hydrophilic microfibrillated cellulose (MFC) in polypropylene (PP) that thus results in an undesired reinforcing effect, this work developed an effective and industrially feasible strategy combining pre‐quaternization of pulp fibers with paper‐making process to fabricate PP/MFC composite with enhanced performance. Effects of MFC consistency, maleic anhydride grafted polypropylene (MAPP) content, and plasma treatment of chopped PP fibers on the mechanical and thermal properties of resultant composites were systematically investigated. The surface‐quaternized MFC obtained by a low‐consistency refiner (L‐MFC) exhibited a higher aspect ratio and degree of fibrillation than the corresponding surface‐quaternized MFC obtained by a high‐consistency one (H‐MFC). It was found that there existed a synergistic effect between pre‐quaternization and the paper‐making process in promoting the dispersion of MFC in PP. As compared with L‐MFC, a higher reinforcing efficiency on PP was achieved for H‐MFC, which was because the former one was more prone to form the fibril aggregates in the PP matrix. Due to both the entangled network of MFC and its nucleation effect on PP, the heat deflection temperature (HDT) of resulting composites was largely increased up to 159.9°C, an increase of 68.7°C with respect to that of PP. The H‐MFC yielded a superior reinforcement on PP than L‐MFC. The optimum mechanical properties of PP/composites were achieved at 15% MAPP. Interfacial bonding between PP and H‐MFC was enhanced by plasma treatment. An increase in Tc of the PP matrix was noted for PP/MFC. A maximum increase of 159.9°C in HDT was achieved for PP/MFC. [ABSTRACT FROM AUTHOR]

Highlights Delamination between adjacent laminas and debonding at the fiber/metal interface are common failure modes in composites and fiber‐metal laminates (FMLs). During the initial stages, these flaws are difficult to detect because of their small size and limited applicability of existing damage‐sensing techniques due to the associated heterogeneity and anisotropy with composites and FMLs. Here, we demonstrate a feasible interlaminar damage‐sensing strategy in composites and FMLs using carbon nanotube (CNT) bucky paper (BP). The microstructure dependence of BP electrical conductivity allows it to sense the damage under varying loading conditions. The accuracy of strain sensing with BP is similar to the commercial 120 Ω strain gauge. The BP sensor accurately detects the interlaminar damage in composites (glass fiber/epoxy, carbon fiber/epoxy) and glass fiber–Al (GLARE) laminates. The delamination is marked by a steep rise in the electrical resistance of BP‐modified coupons. Moreover, the sensing capability of the BP sensor is found to be independent of the electrical conductivity of the tested coupons. Thus, the present approach is applicable to sense the interlaminar damage in a much wider class of structural composites and FMLs. Timely and accurate damage detection in composites is important to ensure their structural integrity. Electrical resistance of bucky paper (BP) varies with deformation. Performance of the BP sensor is comparable to the strain gauge at small strains. BP accurately captures interlaminar damage in composites and FMLs. BP is suitable for damage sensing in a wider class of layered materials. [ABSTRACT FROM AUTHOR]

Highlights The aerospace industries demand for advanced materials necessitates stringent quality control measures, particularly for composite structures to ensure optimal curing and structural integrity. Traditional methods like differential scanning calorimetry (DSC) and dynamic mechanical analysis, while useful, are limited to laboratory settings. This study explores the use of a printed paper‐based sensor for real‐time cure monitoring of glass fiber‐reinforced phenol‐formaldehyde (PF/GF) prepregs. The sensor, composed of a cellulose paper substrate with screen‐printed electrodes, offers flexibility, ease of integration, and cost‐effectiveness compared to commercial polymer‐based dielectric sensors. Real‐time monitoring with the printed paper‐based sensor was conducted at temperatures ranging from 130 to 180°C, both with and without pressure, and validated against DSC and Fourier‐transform infrared (FTIR) spectroscopy. The results showed a strong correlation between real‐time monitoring and the DSC prediction model, as well as FTIR spectroscopy. Notably, the real‐time monitoring revealed a shorter curing cycle on the production line than the predicted cure kinetic model, which is crucial for large‐scale production, such as fabricating honeycomb panels for aircraft interiors. This research underscores the importance of innovative sensor technologies in improving quality control and manufacturing efficiency in aerospace composites. Cure Monitoring of PF‐based prepregs was carried out using paper‐based sensor. Sensor offered reproducibility and seamless integration in composites. Sensor data showed a strong correlation with DSC and FTIR spectroscopy results. Paper sensors enable online monitoring of composite in aerospace manufacturing. [ABSTRACT FROM AUTHOR]

Mineral paper, a synthetic paper‐like material primarily composed of ground calcium carbonate (CaCO3) and a small amount of high‐density polyethylene (HDPE), has emerged as an important alternative to traditional paper and board due to the increasing demand for pulp and paper and the shortage of trees and fibrous material in many regions worldwide. This study aimed to investigate the impact of accelerated weathering and aerobic biodegradation on three different types of mineral papers. The specimens underwent 1000 h of accelerated weathering using a Gardner weathering device and were also buried in soil at a depth of 5 cm for 3 months with regular watering conditions for biodegradability testing. Physico‐chemical characterizations such as optical (whiteness), surface (roughness, contact angle, and paper topography), and chemical properties of the samples were studied before and after the artificial weathering and biodegradation tests. The results revealed a visible color change (darkening) in mineral papers, with an increase in HDPE content leading to a darker color after weathering and biological degradation. However, there were no significant differences in the color change between weathering and soil‐burial tests. The biodegradability test resulted in a decrease in ash content due to the demineralization process. All samples' surface roughness was reduced after weathering and biodegradation tests. The FT‐IR and EDS analyses confirmed the presence of calcium, carbon, and oxygen elements in all three samples, indicating a large amount of calcium carbonate in the mineral papers. The scanning electron microscopy (SEM) images showed the creation of micro holes and cracks on the surface of the samples after weathering and biodegradation. Overall, the soil‐burial test showed more degradation than the weathering test. Highlights: The influence of weathering and biodegradation of mineral papers were studiedAfter soil‐burial test, the ash content decreased due to the demineralizationAfter weathering, micro cracks were created on the surface of the samplesThe degradation of the soil‐burial test was more than the weathering testMineral papers most likely contain carbonate calcium and HDPE [ABSTRACT FROM AUTHOR]

Aramid chopped fibers/polyphenylene sulfide (ACFs/PPS) composite paper exhibits great potential for application in several cutting‐edge areas because of their excellent comprehensive properties. However, the mechanism underlying thermal aging and the role it plays in the performance of ACF/PPS composite paper remain poorly characterized. Herein, we studied the change in the chemical structure of ACFs/PPS composite paper during thermal oxidative aging and investigated the correlation between the evolution of chromophore/auxochrome groups and the development of color appearance in the ACFs/PPS composite paper. Using the color space theory, we established a correlation model among the degrees of thermal aging, the evolution of color appearance, and the changes in the mechanical properties of ACFs/PPS composite paper. On the basis of this model, the degree of aging and the corresponding mechanical strength of ACFs/PPS composite paper under different conditions could be rapidly received by estimating the change in color factor only. This study sheds new light on elucidates and provides a method for the study of polymer thermal oxidative aging. [ABSTRACT FROM AUTHOR]

Aramid materials have been applied in many important civil and military fields. But a major drawback to aramid materials is the susceptibility to UV‐induced damage. In this work, aramid nanofibers (ANFs) and ANF/nano‐ZnO composites were used to protect aramid materials from UV‐induced damage. ANF protective layer was created on the surface of aramid fibers, and the ANF‐coated aramid fibers could be further prepared to aramid paper. Moreover, ANF/nano‐ZnO composites were synthesized and used for stronger UV‐blocking ability. ANFs provided effective protection to aramid material. The properties after UV exposure (about 9.3 years in the natural environment) were largely improved: ANFs improved the retention rate of strength by 17.96% for aramid fibers and by 16.93% for aramid paper. ANFs also showed synergistic effect with UV‐absorbing inorganic nanoparticles. After UV exposure, the tensile strength of aramid paper with ANF/nano‐ZnO composites was even higher than the initial value (121.55%), and the retention rate of strength was 2.43 times higher than the original aramid paper. [ABSTRACT FROM AUTHOR]

Light‐weight, portability and miniaturization are important characteristics for the next generation of high‐performance electromagnetic interference (EMI) shielding equipment. To meet the current demand for high‐performance EMI shielding materials, this paper proposes a simple and reliable method for preparing multilayer paper‐based composites. Paper‐based composites exhibit light weight, flexibility, easy processing and high temperature resistance. A conductive metal–organic skeleton (Ni‐CAT) layer and polypyrrole (PPy) layer were deposited on a polyimide (PI) fiber surface with an in situ synthesis and gas aggregation method to prepare paper‐based electromagnetic shielding composites with good properties. The results showed that the electromagnetic shielding effect (SE) of the paper‐based composites reached 41.0 dB. After the paper‐based composites underwent multiple ultrasonic washing and bending tests, their electrical conductivity retention rate was as high as 90%. Furthermore, the introduction of PPy/Ni‐CAT enhanced the bonding strength of the PI fibers, which caused the tensile strength of the paper‐based composites to reach 22.3 MPa. Due to the good thermal stability of the composites, they can withstand an open flame and protect the equipment during a fire. Thus, these paper‐based EMI shielding composites hold great promise for flexible electromagnetic shielding materials, protection of smart wearable devices and other fields. [ABSTRACT FROM AUTHOR]

Reducing the dielectric constant of insulating paper to improve the dielectric coordination performance of the oil‐paper systems has always been the research hotspot in the transformer insulation material industry. This paper prepares a novel poly‐p‐phenylene terephthalamide (PPTA)/cellulose composite paper with low dielectric constant and good mechanical properties. Various PPTA/cellulose mixing structures were established and the dielectric and mechanical properties were simulated via molecular dynamics simulation. Results showed that the PPTA/cellulose composite system had a lower dielectric constant than the cellulose system, for adding PPTA molecular could reduce the free volume of the system and limit the steering polarization of the dipole, as well as decrease the system polarization intensity. Constructing a three‐layer structure that contains continuous cellulose middle layer could improve the mechanical properties of the composite system greatly. Experimental results verified the simulation results. The dielectric constant of the three‐layer PPTA/cellulose composite paper decreased from 3.98 to 3.49 at 50 Hz, compared to the conventional cellulose paper. Moreover, the tensile strength of the novel three‐layer PPTA/cellulose composite paper (thickness: 130 μm) has reached 9.02 kN/m, increased by 27.6% than the directly mixed composite paper. Molecular dynamics simulation proves to be a promising method for guiding paper modification. Constructing three‐layer PPTA/cellulose structure represents an effective way to prepare a low dielectric constant composite insulating paper with good mechanical properties. [ABSTRACT FROM AUTHOR]

Paper‐based friction materials with phenolic resin as the matrix are prone to thermal damage under harsh working conditions easily leading to materials failure. To satisfy the requirements of high speed and heavy load service situations, paper‐based friction materials with different polyimide resin content were prepared by wet forming technology to reveal the effect of polyimide resin on the properties of composites. And a paper‐based composite with phenolic resin was used for comparison. Results show that compared with the phenolic composite, tensile strength, and shear strength of the polyimide composite were increased by 50.5% and 36.4%, respectively. Due to the strong hydrogen bond in the imide ring of polyimide, the temperature of the polyimide composite at 2% weight loss was 292.7°C, which was 106.3°C higher than that of the phenolic composite. Moreover, the wear rate was reduced by 30.3% because the friction transfer film was produced during friction. To sum up, polyimide resin has the potential to replace phenolic resin under the condition of high speed and heavy load. Besides, the composite with polyimide resin content of 40.0 wt% demonstrated the best wear resistance and considerable strength attributed to the best interface combination. This research lays a theoretical foundation for the application of polyimide resin to paper‐based friction materials. [ABSTRACT FROM AUTHOR]

Sustainable, low‐cost composite materials with improved performance typically contain, in addition to plastics, mineral fillers and fibers. Similar composite materials can also be produced by replacing fillers and fibers with side streams from paper mills using paper for recycling as their raw material. These side streams can be of different qualities and thus various end uses exist. The strength and water adsorption properties of such composites provide many opportunities for their application. Further, their environmental benefits are clear, since the use of these side streams reduces the need to landfill them. The study was also supported by chemical analysis of the side streams. This approach can also bring in additional revenue from the same raw material stream, improving overall resource and economic efficiency. POLYM. COMPOS., 39:4000–4009, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

In this work, poly(para-phenylene terephthalamide) (PPTA) paper sheets composed of PPTA fibers and PPTA fibrids filled with highly crystalline and high ratio of length to diameter potassium titanate whiskers (PTW) were investigated in view of possible employment as reinforcement and cost-reducing materials. The morphological characteristics and the role of PPTA fibrids, the influence of PTW on the mechanical properties, interfacial adhesion, and thermal stability of the PPTA paper sheets were discussed. The results showed that the ductile, flexible and rough morphological characteristics of PPTA fibrids are helpful to improve the properties of PPTA paper. PTTA fibrids strongly wrapped PTW in the PPTA paper sheet was observed, which largely enhanced the retention rate of PTW and further improved the interfacial combination. The presence of PTW improved the mechanical properties and thermal stability of PPTA paper sheets. This research demonstrated the improvement of thermal and mechanical performances of PPTA paper sheets by incorporating of PTW, suggesting a significant cost-reducing potential for the production of PPTA paper composite materials. POLYM. COMPOS., 38:1390-1395, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

In this paper two waste fillers, namely ground tire rubber (GTR) and coffee silverskin (CSS, a waste bio‐product from the coffee‐making process), have been used to produce sustainable ethylene‐propylene‐diene monomer (EPDM) rubber compounds vulcanized on steel sheets to fabricate rubber‐to‐steel bonded systems for industrial roofing applications. The compounds have shown good mechanical performances, with elastic moduli in the range of 13–16 MPa, tensile strength of 13–20 MPa and elongation at break >400%, and strong adhesion to the metal substrate. Moreover, the rubber‐to‐steel bonded systems present good sound insulation properties (mean sound transmission loss [STL] of 39 dB and noise level reduction in simulated hailstones impact tests of 62 dB with respect to bare steel 73 dB). Accelerated UV‐ and thermal‐aging tests have shown excellent adhesion of the compounds to the metal substrate with the CSS acting as an antioxidant agent preventing excessive polymer degradation. The selected waste‐derived materials result in promising fillers for more sustainable rubber compounds. Highlights: Waste fillers were used to produce sustainable rubber compounds.Rubber‐to‐steel bonded systems for roofing applications were produced.Rubber‐to‐steel bonded systems have good sound insulation properties.Rubber‐to‐steel bonded systems have excellent adhesion.Coffee silverskin filler acts as an antioxidant agent. [ABSTRACT FROM AUTHOR]

To investigate the variation of dielectric properties of epoxy resin impregnated paper insulation in different stages of partial discharge (PD) development, a PD experimental platform was established and epoxy resin impregnated paper insulation samples were prepared. According to the discharge amount, the number of discharges and discharge phenomena during the PD process, the PD process is divided into an initial stage, development stage, burst stage, and near‐breakdown stage. The variations of dielectric constant and dielectric loss factor of the sample during different PD development stages were measured by frequency domain dielectric spectrum tester. Scanning electron microscopy was used to observe the microscopic morphological changes of the samples at different stages of PD development. The surface characteristic functional groups at different stages of PD development of the sample were determined by Fourier transform infrared spectroscopy. The results show that: as the PD progresses, the insulation performance deteriorates; under continuous bombardment by high‐speed electrons, the network structure of the fiber surface and the epoxy molecular chain are destroyed, causing the weakening of the binding force between the molecular chains, and the short‐chain structure formed by cracking has a stronger steering ability. Under the continuous action of PD, the inside of the long‐chain molecule breaks and oxidizes, and a large number of small molecules, such as free radicals and monoglucose, are formed. The decrease in the molecular weight of the polymer leads to the weakening of the interaction between the molecules, resulting in an increase in polarization, a large dielectric constant, and an increase in the dielectric loss factor. [ABSTRACT FROM AUTHOR]

Increasing demands and consumption of humankind make an increase in paper production, extending the accumulation of paper production wastes. Due to legislations pertaining to environmental pollution, it has become necessary to search for new areas where these wastes could be used. Some of the processes such as milling, purification, etc. of fillers in the production of building materials are expensive and their cost reduction is desirable; therefore, the objective of this research is to develop strong and multifunctional rigid polyurethane foam composites from bio‐based polyol that are filled with unpurified and high distribution in size, having paper waste sludge (PWS) particles, and to investigate the possibility to recycle them as filler in polyurethane composites. The rational amount of PWS particles is 5% by foam mass. PWS particles improve thermal conductivity, water vapor resistance, density, compressive strength, and modulus of elasticity as compared to neat polyurethane foam matrix. POLYM. COMPOS., 39:1852–1860, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

In this work, a novel thermal conductive and electrical insulation h‐BN@AgNPs/ANFs composite paper was fabricated by vacuum‐assisted filtration approach. Specifically, hexagonal boron nitride (h‐BN) was incorporated via polydopamine pretreatment and subsequent decoration by silver nanoparticles, which served as bridges to link neighboring h‐BN sheets. The results revealed that the thermal conductivity of as‐prepared composite paper increased to 1.032 W/m K with 40 wt% filler loading, about 464% higher than the pure ANFs paper, which was attributed to the efficient thermal conductive networks within the paper and strong interfacial combination through hydrogen bonding. Besides, the as‐prepared composite paper exhibited excellent mechanical property with the maximum tensile strength over 90 MPa, and good electrical insulation performance. More importantly, this work provided a promising strategy to achieve high thermal conductivity ANFs based composite paper by constructing efficient thermal conductive networks, which had potential to be used in the field of electronic packaging. [ABSTRACT FROM AUTHOR]

To create a green, safe, and aldehyde‐free indoor heating environment, an eco‐friendly emulsion polymer‐isocyanate (EPI) adhesive was applied to the preparation of electrothermal plywood with built‐in carbon fiber paper. The optimized process parameters of electrothermal plywood were 0.9 MPa, 120°C, 6 min, and 200 g/m2 for hot‐pressing pressure, temperature, time, and glue spread amount, respectively. After water immersion for 24 h, the bonding strength of wet‐treated electrothermal plywood decreased to 0.89 MPa. The pull‐out cracks of the carbon fiber paper were the main fracture form of the wet‐treated electrothermal plywood, and the wood failure percentage was 0%–10% under the tensile load. Hydrolysis of the adhesive layer of the wet‐treated electrothermal plywood occurred. The relative C and N contents in the wet‐treated electrothermal plywood decreased by 6.1% and 25.3%, respectively. Moreover, the resistance of the wet‐treated electrothermal plywood increased by 273.4% because the internal conductive path was interrupted during the intrusion of the water molecules. The highest electric‐to‐radiant transfer efficiency of the electrothermal plywood was 72.4%, with a power density of 200 W/m2. In conclusion, wet treatment has a significant effect on the bonding strength and electrothermal performance of the electrothermal plywood bonded with EPI adhesive. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced plastics (CFRPs) are widely used in the aerospace, automotive, and construction industries. CFRP prepregs (intermediate products) are generally used in CFRP production, with a large number of prepreg cut‐offs being discarded during cutting processes. There is strong demand for a method for recycling carbon fiber prepreg cut‐offs. This paper proposes a method for recycling such material, which is characterized by low cost and high added value, in order to foster the development of a recycling‐oriented society. We prepare carbon tapes (CTs) by cutting discarded cut‐offs according to their size so as to maximize fiber length. Using a simple water CT dispersion method, we fabricate uniform CT sheets and mold a recycled CT‐reinforced composite (R‐CT‐RC). Sample prototyping and mechanical characteristic testing indicate that this R‐CT‐RC is characterized by low recycling cost and desirable mechanical properties. Recycled CT‐reinforced composite with thermoplastic (R‐CT‐RC/TP), which is prepared by adding thermoplastic resin between CTs, can be re‐molded and therefore readily re‐recycled. [ABSTRACT FROM AUTHOR]

Resin‐infiltration technique has been employed as a versatile method to improve nanofiller dispersion in matrix. In this article, fabrication of polyvinyl chloride (PVC)/p‐phenylenediamine (PPD)/functional graphite (F‐G) and PVC/F‐G composite paper have been reported through resin‐infiltration techniques. Synthesis and characterization of PVC/PPD/F‐G and PVC/F‐G composite papers for enhanced structural, morphological, thermal, hardness, wettability, and conductivity properties have been studied. Moreover, the effect of increasing amount of F‐G and PPD/F‐G nanofiller on composite paper properties was scrutinized and compared. Transmission electron microscopy and scanning electron microscopy depicted better graphite nanofiller dispersion in PVC matrix and network formation in PVC/PPD/F‐G composite paper. Maximum degradation temperature (Tmax) of PVC/PPD/F‐G 0.08 composite paper (517°C) was found higher than PVC/F‐G 0.08 composite paper (484°C). Dynamic contact angle analysis shows that the PVC/PPD/F‐G and PVC/F‐G composite papers have better surface wettability than neat PVC. PVC/PDD/F‐G 0.1 and PVC/F‐G 0.1 composite papers possess high microhardness values up to 39.67 and 32.76 Hv, respectively. Electrical conductivity of 8.97 × 10−3 and 5.89 × 10−3 S m−1 was observed for 0.08 wt% PPD/F‐G and F‐G loaded samples. POLYM. COMPOS., 39:4176–4187, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Nitrile butadiene rubber (NBR) is widely used in the production of oil and fuel‐resistant rubber parts. Poly(p‐phenyleneterephalamide) (PPTA) pulp is used as a reinforcing fabric in NBR composites to improve its mechanical properties despite the weak bonding between NBR and PPTA pulp. In this work, PPTA pulp was modified by interfacial polymerization of dopamine (DOPA). A surface‐adherent poly(dopamine) (PDA) film was formed on the surface of the PPTA pulp, which improved bonding to NBR and mechanical properties of the prepared composites. The surface of the modified PPTA pulp was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X‐ray photoelectron spectroscopy. The results demonstrate that PDA was successfully functionalized on the PPTA pulp and that the surface of the composite was rougher after modification. The effects of treatment conditions on the mechanical properties of NBR/pulp composites were also investigated. The tensile strength markedly improved with treating time of 30 h at a DOPA concentration of 2 g/L. Strong interactions, including hydrogen bonding and adsorption, play an important role in the tensile strength of the material. Our results demonstrate that surface modification by PDA is beneficial for improving the strength of the NBR matrix. POLYM. COMPOS., 40:E476–E483, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

This study presents a novel hydrophobic lignocellulosic bioplastic from corn stover reinforced by oxidized cellulose and in situ regenerated lignin. Cellulose‐lignin mixture as a matrix was obtained by acid‐recyclable deep eutectic solvent (DES) pretreatment of corn stover in mild conditions. Triethoxy(octyl)silane (C14H32O3Si) was employed to improve the water stability of the bioplastic by vapor deposition. The results show that the hydrophobic bioplastic has a high tensile strength, measuring 62.36 MPa. The water contact angle of the bioplastic was increased from 8.50° to 121.9° after hydrophobic modification. We prepared oxidized cellulose‐reinforced cellulose paper by different particle size distributions of oxidized cellulose to investigate the reinforcement of oxidized cellulose. The tensile strength of oxidized cellulose cellulose paper increased from 14.41 to 21.18 MPa with the addition of oxidized cellulose. The zeta potential of oxidized cellulose is −47.99 mV, which shows a more negative charge due to carbonyl groups. The repulsive force of oxidized cellulose contributes to the formation of a brick‐and‐mortar microstructure with cellulose‐lignin mixture. It demonstrates that oxidized cellulose can act as bio‐adhesives and has a good toughening effect on the mechanical properties of bioplastic. Highlights: Lignocellulosic bioplastic was prepared by DES pretreatment of corn stover.Oxidized cellulose was used to reinforce the lignocellulosic bioplastic.The tensile strength of the bioplastic was 62.36 MPa after the reinforcement process.Trieth‐oxy(octyl)silane was employed to improve water stability.The water contact angle of the bioplastic was increased from 8.50° to 121.9°. [ABSTRACT FROM AUTHOR]

This article studies the potential of deinking paper sludge (DPS) and recycled high density polyethylene (RHDPE) for biocomposites (DPS/RHDPE). Different DPS loadings (0 to 20 wt%) and compatibilizer content (0 to 4 wt%) were used in (DPS/RHDPE) formulations. A commercial paper wet‐strength agent polyamideamine‐epichlorohydrin resin (PAE) was used as DPS binder. The effects of DPS composition and PAE content on RHDPE/DPS biocomposites performance were studied. First, the chemical composition, morphology and thermal behavior of DPS were characterized using X‐ray diffraction, scanning electron microscopy, fiber quality analyser, and thermogravimetric analyses. The effect of the chemical treatment was evaluated using infrared spectroscopy (FTIR). Finally, crystallization behavior and tensile properties of DPS based biocomposites were discussed. Results revealed that DPS have a nucleating effect thanks to the presence of minerals such as calcium carbonate and talc. DPS increased the stiffness and the tensile strength of RHDPE. PAE could also serve as a compatibilizer between fibers and RHDPE. POLYM. COMPOS., 39:616–623, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Recycled newspaper-reinforced sustainable and biodegradable composite sheets and fibers were fabricated with camelina meal, a by-product of camelina oil extraction-based resin. To prepare uniform composite sheets and fibers, the camelina meal was ground and sieved to remove large particles and some impurities and converted into resin by dissolving it in water and precuring at 75°C water bath. Sieving process improved protein contents by 4.7% and reduced fat contents by 4.2%. Recycled newspaper was used as a reinforcing agent to improve tensile properties and increase water resistance of the camelina meal-based biodegradable composite sheets and fibers. Increasing newspaper content increased fracture stress, Young's modulus, and water resistance property. However, the uniform sheet could not be formed when recycled newspaper content was above 30% (wt/wt camelina). Scanning electron microscope photomicrographs of fracture surfaces showed that at higher newspaper content longer fibers protruded out from the camelina resin. POLYM. COMPOS., 33:1969-1976, 2012. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A new processing method was developed to fabricate nanocomposites with a high concentration of multilayer graphene (MLG) in a highly oriented morphology. MLG was first dispersed in a water-based solution with the aid of polyethylenimine. A thin MLG film (paper) having highly in-plane aligned platelets was produced by using a vacuum-assisted self-assembly (VASA) technique. After heat treatment, the MLG paper was immersed in an epoxy/acetone bath at room temperature under vacuum to produce an epoxy impregnated composite. After removal of the acetone, nanocomposites consisting of multiple layers of the MLG paper with up to 27 wt% MLG were fabricated and thermally cured. Scanning electron microscopy (SEM) examination showed that the MLG was well dispersed and aligned, and the MLG paper was fully impregnated with epoxy resin. At 30°C, dynamic mechanical analysis (DMA) results showed that the storage modulus of the resulting nanocomposites with 27.2 wt% MLG reached 10.2 GPa, a 300% increase compared to the neat epoxy. The resulting composites also exhibited electrical conductivity as high as 35 Siemens per centimeter (S/cm). This research demonstrates that the VASA processing technique is capable of fabricating well aligned, high content MLG nanostructured polymer composites with high electrical conductivity. POLYM. COMPOS., 37:2897-2906, 2016. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes (MWCNTs) have extraordinary electrical conductivity but limited applications due to the ease of agglomeration, especially in thermoplastic composite. With the aim of achieving high electromagnetic interference shielding performance by applying MWCNTs in thermoplastic matrix, MWCNTs were made into buckypaper (BP) and then hot pressed with PP/PLA/TiO2 hybrid films, forming sandwich‐structured BP/PP‐PLA‐TiO2 hybrid composite films. BP was examined in terms of morphology, cell structure, and electrical conductivity, while BP/PP‐PLA‐TiO2 hybrid composite film was tested for electromagnetic shielding effectiveness (EMSE), thermal properties and UV‐cut efficacy. It was found that using vacuum filtration successfully produced BP with a smooth and sleek surface and an even porosity ranging between 20 and 45 nm. The electrical conductivity of BP was proportional to its thickness. About 90 μm‐thick BP had 75.62% lower surface resistivity and 36.63% higher electrical conductivity than 30 μm‐thick BP. Moreover, the EMSE of BP/PP‐PLA‐TiO2 composite film increased as a result of the higher thickness of BP. When the thickness of BPs was 90 μm, the BP/PP‐PLA‐TiO2 composite film had an average EMSE of 40 dB at 0–3 GHz and a peak of 70 dB, and 119% higher tensile strength and 11% higher elastic modulus than those of PP/PLA/TiO2 composite film. BP/PP‐PLA‐TiO2 composite film had UV‐cut efficacy that was close to 0%. The addition of BP was proven to improve the crystallization and thermal stability. POLYM. COMPOS., 40:3065–3074, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]