Waste Paper Fibers Research Articles

Waste paper recycling and its application in modification of the green biodegradable material

Waste paper is a significant waste resource that is part of waste polymer materials in vast quantities, and there is now a lot of focus on the development of high-value conversion and use technologies for waste paper. High-quality waste paper fibers (WF) were extracted in this work from the deinked waste paper pulp by mechanical process. Then, waste paper fiber/polylactic acid (WF/PLA) composites were synthesized using hybrid forming technique to investigate the modification impact of WF on WF/PLA composites. The results showed that a certain additive amount of WF could improve barrier property of WF/PLA composites. When WF was added of 3.5 %, a water vapor transport rate was only of 59 g/(m2d), and the barrier property was increased by 82.8 %. Besides, WF/PLA composites also possessed good thermal stability. With the additive WF ranging from 3 % to 4 %, the initial decomposing temperature of WF/PLA composites increased by 19℃. Importantly, the transparency of PLA was slightly improved with a certain addition of WF. Hence, this work realized the performance enhancement of WF/PLA composites by a small addition of WF, and reduced the production cost of PLA to some extent, which had a good application prospect.

Converting large-scale waste paper fibers into lanthanum-modified cellulose carbon aerogel adsorbents for efficient phosphorus removal

This study presents the synthesis of a novel lanthanum-modified cellulose-based carbon aerogel (La-CCA) from waste printing paper, aimed at addressing the issue of phosphate pollution in aquatic environments. The objective was to develop an effective and sustainable adsorbent to mitigate eutrophication caused by excess phosphates in water bodies. La-CCA exhibited a remarkable phosphate adsorption capacity, peaking at 44.32 mg/g under optimal conditions, demonstrating its efficiency as an adsorbent. The novelty of this work lies in the use of waste paper as a raw material, coupled with lanthanum modification, which enhanced adsorption performance through multiple mechanisms, including electrostatic interactions, ligand exchange, and inner-sphere complexation. The study also discussed the retention of the microfibrous structure of cellulose, contributing to the material’s stability and functionality. Comprehensive analyses including zeta potential, FTIR, and XPS elucidate the underlying adsorption mechanisms. La-CCA was demonstrated to be easily separable from solutions with minimal lanthanum leaching, particularly under conditions above pH 3.0, underscoring its potential for practical applications in phosphate removal from nutrient-enriched waters.

Characteristics of natural corn starch/waste paper fiber composite foams treated by organic-inorganic hybrid hydrophobic coating technology.

With the growing global awareness of environmental protection, the demand for biodegradable materials to replace traditional plastic foam has become increasingly urgent. Starch-based foam, with its abundant availability, low cost, and biodegradability, has shown great potential as an alternative to plastic foam. However, its inherent high hydrophilicity and relatively low mechanical performance limit its widespread application. The aim of this study is to modify corn starch (NCS) and waste paper fiber (WPF) using citric acid (CA) and stearic acid (SA), and to develop an efficient hydrophobic coating through an organic-inorganic hybrid approach. This successfully resulted in the preparation of hydrophobic corn starch/waste paper fiber composite foam materials. Experimental results showed that the foam materials treated with a palmitic acid (PA)-modified nano-SiO2 coating (MCF@PA) exhibited excellent hydrophobic performance, with a water contact angle reaching as high as 138°, and a significant reduction in moisture absorption to 3.1%. In water immersion tests, the material maintained buoyancy and shape stability, demonstrating excellent self-cleaning properties. Additionally, the coating significantly enhanced the material's compressive strength, increasing by 90kPa, while also retaining thermal stability. However, the coating prepared by this method increased the material's hardness and reduced its biodegradability, which poses challenges for environmental sustainability. This study provides a new approach for preparing high-strength foam materials with excellent hydrophobicity and mechanical performance, paving an economical and efficient pathway for industrial production.

Characteristics and degradability of laser print waste paper fiber reinforced PLA resin matrix composite materials

AbstractAs 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.

Compressive Strength of Geopolymer Mortar Reinforced with Rice Husk Fibers

Geopolymer concrete has been proposed to minimize carbon dioxide emissions related to the cement production industry. This environmentally friendly material consists of industry waste materials activated chemically by an activation solution. In this study, the geopolymer mortar has been designed with 70% fly ash and 30% metakaolin. Hydroxide sodium in 14 molar concentrations blended with sodium silicate in a 2.5:1 ratio was used as the activation solution. Rice husk fibers were added as reinforcement in (1%, 1.5%, and 2%), and waste paper (paper pulp and paper ash) was added in (1%, 2%, and 5%) by volume of cementitious material. The geopolymer mortar samples underwent a curing process through exposure to a temperature of 60°C in an oven for 24 hours. The findings indicate that the samples reinforced with 2% rice husk fibers exhibited the most significant improvement in compressive strength, with 59% and 55% increases after 7 and 28 days of curing, respectively. In general, using waste paper and rice husk fibers significantly enhanced the compressive strength of geopolymer mortar.

Mechanical, Durability, and Microstructure Assessment of Wastepaper Fiber-Reinforced Concrete Containing Metakaolin.

This study evaluates the potential use of discarded plasterboard paper as fibers from buildings to reinforce concrete. Various concentrations of wastepaper fibers (0.5%, 1%, 1.5%, 2%, and 2.5% by weight of the binder) were investigated in this research. To mitigate the water absorption effect of the paper fibers, metakaolin was employed as a partial cement replacement. The results demonstrate that the inclusion of the wastepaper fiber enhances the mechanical and durability performance of the concrete. The optimal fiber proportion was identified as 1%, leading to a 29% increase in the compressive strength, a 38% increase in the splitting tensile strength, a 12% decrease in the water absorption, and a 23% decrease in the drying shrinkage with respect to the concrete containing 20% metakaolin. However, exceeding this optimal fiber content results in decreased mechanical and durability properties due to the fiber agglomeration and non-uniform fiber distribution within the concrete matrix. Based on the microstructural analysis, the improved performance of the concrete is ascribed to decreased porosity, more refined pore structure, and reduced propagation of microcracks within the concrete matrix in the presence of wastepaper fiber. According to the results, concrete containing 20% metakaolin and 1% wastepaper fiber exhibits durability and mechanical properties comparable to those of the traditional concrete. This finding highlights the significant promise of reducing dependency on conventional cement and incorporating suitable recycled materials, such as discarded plasterboard, and secondary by-products like metakaolin. Such a strategy encourages the preservation of resources, reduction in carbon dioxide emissions, and a decrease in the ecological footprint resulting from concrete production.

Enhancing the performance of waste-paper particleboard using silica and aluminum hydroxide fillers

Composites used as particleboard have recently been developed using waste-paper fibers mixed with natural rubber compound at a weight ratio of 70/30 %. The effects of silica and aluminum hydroxide fillers were studied at 0, 15, 30, 45, and 60 phr. The results showed that the hardness of the waste-paper particleboard increased with the filler content. Both types of fillers led to a slight increase in the density of the composites. Moreover, the fillers reduced the hygroscopicity and swelling of the particleboard. The use of silica resulted in lower hygroscopicity, providing greater flexural resistance and elastic modulus compared to using aluminum hydroxide. Additionally, the minimum limiting oxygen index (LOI) required to ignite the sample was slightly higher with the addition of both fillers, with silica exhibiting a higher value than filled aluminum hydroxide. Furthermore, the thermal decomposition of the specimens from the TGA test was reduced as both fillers were added, especially at temperatures above 350°C.

Manufacturing of Solid Substrates Using Waste Paper Fiber and Biochar

Manufacturing of Solid Substrates Using Waste Paper Fiber and Biochar

Wastepaper fiber‐reinforced concrete containing metakaolin: Effect on fracture behavior

AbstractPlasterboard, a commonly utilized construction material, comprises a gypsum core nestled between two paper layers. Gypsum after demolition of plasterboards is a recyclable waste that has been reused into new plasterboard or other purposes such as agricultural products. However, there is a lack of understanding on the potential for recycling the paper layers. This study investigates the use of wastepaper fibers, obtained from the paper layers, as a reinforcing material and metakaolin as a partial cement replacement material in concrete. This study demonstrates the ability of the paper from waste plasterboard for reinforcing concrete. Wastepaper fibers were used at different concentrations ranging from 0 to 2.5% by weight of binder. Bending test was conducted for assessing fracture behavior of concretes, including load bearing capacity, modulus of rupture, crack mouth opening displacement (CMOD) at the load bearing capacity, fracture toughness, and fracture energy. Slump, axial compression, and scanning electron microscopy (SEM) were also conducted on the concretes. It is found that incorporating wastepaper fiber by up to an optimum content of 1.5% results in an increase in the compressive strength (57%), flexural load bearing capacity and modulus of rupture (31%), CMOD displacement at load capacity (14%), fracture toughness (37%), and fracture energy (73%) of the metakaolin‐based concrete. However, further increase in the wastepaper fiber content results in decreased mechanical properties of the concrete, which is due to the fiber agglomeration and non‐uniform distribution within the concrete matrix. Based on the results, the concrete with 20% metakaolin and 1.5% wastepaper fiber experiences similar mechanical properties to the conventional concrete. The results of this study underscore the substantial potential of leveraging waste materials such as wastepaper and by‐products like metakaolin to diminish reliance on conventional cement. This approach not only enhances the mechanical properties of concrete but also fosters sustainable building practices by promoting the recycling of waste materials, reducing carbon footprint, and mitigating the environmental impacts inherent in traditional concrete production.

Application of waste paper in composite materials based on mineral fibers

Abstract. In this study, a composite material was successfully produced by incorporating waste paper and basalt fibers. The utilization of waste paper as a raw material contributes to sustainable practices and waste reduction. The physical and mechanical properties of the obtained composite material were comprehensively investigated to evaluate its potential for various applications.The physical parameters of the composite material, such as density and porosity, were measured to assess its structural characteristics. Density provides insights into the compactness and mass per unit volume of the composite, while porosity indicates the presence of voids or open spaces within the material. These parameters play a crucial role in determining the overall performance and suitability of the composite for specific applications.Furthermore, the mechanical properties of the composite material were examined to evaluate its strength, stiffness, and durability. Tensile strength, flexural strength, and impact resistance were among the key mechanical parameters studied. Tensile strength determines the material's ability to withstand pulling forces, while flexural strength measures its resistance to bending or deformation. Impact resistance evaluates the material's ability to absorb energy when subjected to sudden or dynamic loads.

Preparation of waste paper fiber-reinforced biodegradable polybutylene adipate terephthalates (PBATs) and their feasible evaluation for food package films with high oxygen barrier and antistatic performances

With polyethylene glycol-modification of waste paper fiber as the hydrophilic enhancer and prescription of polybutylene adipate terephthalate as well as antistatic agent/processing aid, a food package film with great transparency, good antistatic property, and high oxygen barrier capability have been prepared by T-Die extrusion and blade-coating procedure. To evaluate its feasibility for food package, the prototype of food container has been also manufactured, eventually examining its anti-corrosion capability for the milk. Experimental results elaborate that lab-made food package film can efficiently obstruct the entry of oxygen in the air into the food container, consequently dramatically extending the expiration date of milk.

Pore structure and cushioning properties of wastepaper-pulp-reinforced starch-based foams

Foamed plastics do not readily degrade, but degradable starch foam has uneven pores and poor mechanical properties. To improve the cushioning performance of starch foams, a sustainable starch-based packaging cushioning material is prepared through microwave foaming using waste corrugated paper fibers as the reinforcement material. The effects of different fiber contents on the structure and cushioning properties of starch-based foams are studied, and the possibility of replacing petroleum-based foams is discussed through comparisons with conventional cushioning materials. The results indicate that the pore structure of starch-based foaming materials can be controlled by changing the fiber dosage, and a small or excessive amount of fiber is not conducive to the uniform foaming of starch-based composite foams. When 3 g of wastepaper fiber (17.6% by weight of starch) is added, the average diameter of the starch-based foam pores is small, the pore size distribution is relatively uniform, the minimum buffer coefficient is 4.38 and the mechanical properties are closer to those of expanded polystyrene. A peak acceleration of 942.89 m/s2 is obtained from the packaging parts with starch-based foaming materials after drop testing, which reduces the impact load by nearly 50% compared with that of packaging without a cushioning liner. This has the potential to become a sustainable alternative to petroleum-based packaging foams.

Sustainable Cement Composite Integrating Waste Cellulose Fibre: A Comprehensive Review.

This review presents the research conducted to date in the field of cement-based composites reinforced with waste paper-based cellulose fibres, focusing on their composition, mechanical properties, and durability characteristics. The literature demonstrates that the properties of raw material (depending on their own chemical composition) significantly influence the formation of the cement composite binders. When considering fresh properties, the presence of silica and magnesium compounds generally lead to favourable effects on the setting of the cement composite when combined with waste paper cellulose fibre. Reduction in density values, i.e., approximately 25%, was observed with the inclusion of waste paper fibres from 20 to 80% in cement composites. The homogeneous dispersion of fibres in the matrix is one of the crucial factors to achieve in order to develop composites with well-balanced mechanical properties incorporating waste paper cellulose fibres. Hence, dispersion of fibres can be improved by increasing water quantity corresponding to the optimal value, which was a water/cement ratio of 0.64 leading to optimum strength properties of the composite. Even though the effect of fibre dispersion in the matrix improves with the addition of water, higher porosity and voids govern the strength properties beyond an optimum water-to-cement ratio. Higher porosity leads to an increase in the water absorption and a lowering of the thermal conductivity properties with the addition of paper fibre in cement binders. Paper fibre absorbs a high amount of water leading to higher water absorption. This phenomenon is related to the hydrophilic nature of cellulosic fibres absorbing some volume of water due to their microporous structure.

Study on Biodegradability and Mechanism of Cyanoethylated Waste Paper

With white pollution caused by petroleum plastics becoming an environmental issue of global concern, biodegradable plastics have become a research hotspot, and biodegradable materials made from plants have been attracting attention. Based on previous studies, this paper studied the biodegradability of thermoplastic cyanoethylated waste paper (CWP) by microbial experiment, and preliminarily explored the degradation mechanism. The results showed that: (1) the biodegradability of CWP was better than that of waste paper, and the higher the degree of modification, the better the biodegradability of CWP; under the action of Trichoderma reesei, the degradation rate of CWP containing 20.79% nitrogen was about 24% after 144 h (hours) of degradation; (2) The degradation rate of CWP was about 45% after 144 hours degradation by microbial complex bacteria, which was mainly due to the synergistic effect of cellulose degrading enzymes secreted by microbial degrading bacteria, which greatly improved the degradation rate of CWP. (3) The improvement of biodegradability of CWP was mainly due to the change of the morphology of the fibers by cyanoethylation reaction, which increased the contact surface and destroyed the crystal structure of the waste paper fibers. The increase of the amorphous region and the distance between the crystal planes was more conducive to the cellulase entering into the CWP, thus improving the degradation rate. (4) Structural analysis of CWP before and after degradation showed that microbial degradation bacteria destroyed C≡N bond and formed hydrocarbon bond, and further destroyed the crystal structure of CWP without changing the crystal form of the fiber.

Determination of Physical and Mechanical Properties of Waste Paper Boards Supported by Wood Chips and Chopped E-glass Fiber

Today, legal regulations, along with social awareness, have made waste management a necessity. Depending on the type of waste, technological developments have enabled an increase in the number of approaches, e.g., reusing, recycling, and manufacturing of different products. In this study, low-density boards were produced using different proportions of office waste paper, wood chips, and chopped E-glass fiber. Waste paper and glass fiber formed the middle layer of the boards and wood chips comprised the surface layers. The density, water absorption, and thickness swelling properties of the boards were investigated. Among the mechanical properties, the modulus of rupture, modulus of elasticity, and internal bond strength were determined. The use of wastepaper led to a reduction in the modulus of rupture and modulus of elasticity of the boards. An increase in the glass fiber ratio contributed positively to the water absorption and thickness swelling properties, whereas it directly led to decreases in the internal bond strength, and the modulus of rupture and modulus of elasticity values. Nonetheless, the low-density boards were able to meet the minimum modulus of rupture and modulus of elasticity specified in ANSI 208.1 standards, while only one variation met the IB requirements.

High-value utilization method of digital printing waste paper fibers-Co-blending filled HDPE composites and performance improvement

Due to accelerated modernization, urban environmental waste is being generated at an exponential rate, and paper is one of the largest solid wastes. Among them, digital printing waste paper has remarkable fiber quality and purity, making it a superior renewable fiber resource. However, the printing method and ink/toner used in the digital printing process are different from traditional printing methods, and the waste paper is relatively difficult to deink, resulting in the traditional waste paper utilization industry (recycled paper) is not given much attention and becomes low-value waste paper. How to realize the resourcefulness and high-value and efficient utilization of digital printing waste paper fiber (DPWF) is a real problem that needs attention in the field of renewable resources. In this paper, DPWF was used in the field of melt blending filled thermoplastic resin composites to avoid the waste paper deinking process while improving various properties of the material. It is shown that the best mechanical properties of the composites are achieved at 35% DPWF content. At the same time, coupling agent was used to further improve the properties of the composites in response to the interfacial incompatibility between fiber and resin. The best modification effect was achieved when the coupling agent was added at 3%, at which time the interfacial, water absorption, crystallization and thermal properties of the composites were improved, among which vinyltrimethoxysilane (A171) and γ-methacryloxypropyltrimethoxysilane (KH570) had significant effects.

Low-temperature hydrothermal modification of waste paper fiber adsorbent to enhance removal benzothiophene sulfide efficiency from oil: kinetics and equilibrium study

Thiophene sulfide is difficult to be removed by hydrodesulfurization. In this study, ZnCl2-waste paper fiber activated carbon was used as adsorbent to remove thiophene sulfide from simulated oil by hydrothermal modification. Under the optimum condition of ammonia modification, the adsorption capacity of modified adsorbent to BT is 14.8 mg S/g, 2.98 times that of unmodified. BET, FTIR and Boehm analysis showed that the mesopore volume of ammonia modified adsorbent increased by 96.62% and the mesopore ratio increased from 12.58% to 43.40%, which was conducive to improving the adsorption rate. After modification, the basic groups on the surface of the adsorbent increased by 44.3 times, and –NH3+, –OH and –NH2 enhanced the electron attraction and hydrogen bonding force between the adsorbent and BT molecule. Adsorption isotherms, adsorption kinetics and adsorption thermodynamics show that the adsorption process is spontaneous, entropic and exothermic. The pseudo-second-order kinetic rate constant increases with the increase of adsorption temperature, indicating that the increase of temperature is beneficial to accelerate the adsorption rate. The adsorption desulfurization process follows the mechanism of single and multilayer adsorption mixing. The results of this study can help to reveal more clearly that biobased activated carbon can be modified to adsorb thiophene sulfide.

The Reinforcing Effect of Waste Corrugated Paper Fiber on Polylactic Acid

To improve the recycle value of waste paper and promote circular economic development, waste corrugated paper fiber (WCPF) was used as a reinforcing agent to prepare waste corrugated paper fiber/polylactic acid (WCPF/PLA) composites via dichloromethane solvent which can be reused. The WCPF in the waste corrugated paper is extracted by beating in a Valli beating machine for different time lengths and grinding in a disc grinder. The effects of beating time and the content of WCPF on the microstructure, mechanical properties, thermal decomposition process, and crystallization properties of the WCPF/PLA composite were studied. The result shows that the WCPF can be well separated from each other and can be evenly dispersed in the PLA matrix. When 25 wt% WCPF which was beat for 30 min was used, the composite has the greatest improvement in tensile property. This study provides a new process for the recycling of waste paper in the application of polymer reinforcement. The research on waste paper fiber and degradable polymer composite is of great significance for reducing environmental pollutants and developing circular economy.

Preparation and properties of multifunctional polyaspartic acid/waste paper fiber-based superabsorbent composites

Superabsorbent composites (SACs) are widely used for agricultural applications acts as a “miniature soil moisture reservoir” for plants. While these substrates have excellent water retention properties, they often suffer from production costs and a variety of environmental challenges. Herein, polyaspartic acid (PASP), waste paper fibers (WPF) and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) graft copolymerize acrylic acid (AA) to prepare a novel multifunctional PASP-g-P(AA-co-AMPS)/WPF SACs. The synthesis conditions use to prepare the PASP-g-P(AA-co-AMPS)/WPF SACs are optimized, including PASP content, mass ratio of AMPS and AA, initiator content and cross-linker content. In addition, the water retention, salt and acid resistance, reversible swelling and temperature sensitivity of SACs are also investigated and analyzed in detail. Due to the uniform distribution and the rich pore structure, it has a maximum equilibrium adsorption capacity of optimal SACs in distilled water, tap water and NaCl solution (0.9 wt%) are determined to be 731.0 g g−1, 189.2 g g−1 and 81.4 g g−1, respectively. Thus, PASP-g-P(AA-co-AMPS)/WPF SACs exhibit excellent environmental tolerance and provide a promising strategy for sustainable agriculture and desertification control.

Preparation of a strong, mildew-resistant, and flame-retardant biomimetic multifunctional soy protein adhesive via the construction of an organic-inorganic hybrid multiple-bonding structure

It is important but challenging to develop multifunctional soy protein adhesives with high bonding strength to replace toxic formaldehyde-based adhesives used in the wood-based panel fabrication industry. In this study, inspired by arthropod cuticles, the epoxide-crosslinked soy protein isolate (SPI) was used to form the covalently-bonded network, and dopamine-functionalized waste paper fiber (WPF-PDA) was synthesized as the catechol groups donor to form the hydrogen bond network and physically-enhancement, copper hydroxide was used as an inorganic material that chelated with the catechol groups of WPF-PDA to form the ionic bond network. This formed an organic-inorganic hybrid multiple-bonding structure in the soy protein adhesive. The results showed that the dry/wet shear strength of the plywood prepared by the resultant adhesive increased by 46% and 144% to 2.0 and 1.22 MPa, respectively, compared with SPI adhesive. The fracture toughness increased by 145%, and the residual rate of the adhesive increased by 18.6%, indicating that the bonding strength, toughness, and water resistance of the adhesive were significantly improved. In addition, the anti-mildew time of the adhesive increased from 1 d to more than 40 d, while the maximum heat release rate and total heat release decreased by 32.5% and 5.8%, respectively. This strategy provides a potential method to develop high-performance and multifunctional bio-adhesives, composites, and hydrogels.