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To investigate the role of spent sulphite liquor (SSL) retained on neutral sulphite bagasse pulp in the binding action of phenolic resin, for the purpose of enhancing its performance to produce high quality agro‐based composite.

Pulps used in this work as agro‐based fibres were prepared from Asplund defibrator and neutral sulphite pulping processes. The performance of the resol resin in presence of SSL, were evaluated in terms of the effects of SSL constituents and using novolac as phenolic resin, in comparison with that prepared from pulps in absence of SSL and conventionally prepared resol – Asplund bagasse composites. Preparation of pulp free from sulphonyl groups and pre‐out‐precipitating the resol or lignosulphonic acid (LSA) on the strength and water resistance properties of the composite produced was also examined. The degraded hemicellulose and LSA in SSL were polynomial correlated with the changes in composites properties.

All neutral sulphite pulps investigated, in presence of SSL, were found to enhance the strength quality of agro‐based composite compared to commercially available resol‐agro‐based composite. The retained SSL on NS‐raw bagasse pulp could replace the Asplund bagasse pulp together with resol resin in production of agro‐composite. As well as, using neutral sulphite – Asplund bagasse pulp reduced the percent of added resol to half, to produce commercial resol agro‐based composite. The performance of the composite produced from novolac resin‐SSL‐neutral sulphite pulp and resol‐LSA‐neutral sulphite pulp exceeded 1.5 to 1.9 times the strength of commercially available composite.

Despite the SSL retained on pulp success in improving the strength property of the resol resin‐agro‐composites, but it has an undesirable effect on water resistance of the product. This problem was resolved by avoiding the undesirable effect of sulphonyl groups on pulp fibres as well as the degraded hemicellulose in SSL.

The approach developed provided a simple and practical solution to enhancing the performance of phenolic resin as well as agro‐fibres and SSL wastes in the production of high performance lignocellulosic composite.

The resol, together with SSL constituents retained on neutral sulphite pulp, are economic bonding agents for agro‐fibres and could be used in wood mills for production of medium density fibre‐board.

The purpose of this paper is to prepare high-performance agro-based composites from the non-toxic rice bran-urea-formaldehyde (RB-UF) adhesive system. Investigations have continued for production high performance agro-based composites using environmentally acceptable approaches. The utilisation of such system with the available used local agro-based wood products (sugar-cane bagasse, SCB) adds economic value and helps reducing the environmental impact of commercial urea-formaldehyde (UF) adhesive, and most importantly, provides a potentially inexpensive alternative to the existing commercial artificial wood-panel mills.

Optimising the process for incorporating the RB in UF, as wood adhesive for binding the bagasse fibres, was carried out, by partially replacing commercial UF by denaturalised RB in slurry (wet) and dry form or through synthesis of UF. The denaturalisation of RB was carried out at different pHs (10-11) and at temperature 60°C for two hours. While incorporating the RB during synthesis of UF, it was carried out according to the method reported elsewhere. The formulation of adhesive components, pH value of the denaturalisation stage and the process of incorporating the RB were optimised. Assessment of the role of RB adhesive was specified from its free-formaldehyde (HCHO) content, as well as the properties (mechanical and physical properties) of the produced composites of bagasse particle board type, in comparison with the environmental impact of commercial thermosetting resin (UF).

The promising adhesive system exhibits improvement in the environmental performance (as E1 type) over a commercially UF adhesive (as E2 type), besides providing boards fulfill the requirements of grade H-3 (according to ANSI A208.1 (NPA1993). This adhesive system was resulted from replacing 30 per cent of UF by denalturalised RB (at pH 10) in slurry form. Where, its reduction in free-HCHO reached 53 per cent, as well as modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB) and TS of the produced boards were approximately 24.2 N/mm2, approximately 3753 N/mm2, approximately 0.84 N/mm2 and approximately 11.4 per cent, respectively.

The eco-adhesive with relatively high percentage of low-cost commercial UF (70 per cent) and 30 per cent RB, as oil production by-product, in slurry form provides good board strength and is environmentally friendly compared to SCB-based composite properties, with that produced from commercial UF. The mechanical (MOR, MOE and IB) and water-resistance properties of the produced composite comply with the standard values.

The approach provided low HCHO-free UF adhesive with good comparative board strength and water resistance and reasonable working life. Replacing 30 per cent of UF by RB in slurry form and denaturalised at pH 10 is considered a promising inexpensive alternate adhesive (as E1) in the wood industry based on SCB wastes.

Incorporating the RB by-product of oil production to commercial UF will be beneficial for saving the health of wood co-workers and motivating the wood mill to export its wood products.

It provided a potentially simple way to improve both the utilisation of commercial UF and SCB as industrial substrates for particle-board production. This will benefit farmers, local wood mills in Upper Egypt, significantly. Meanwhile, incorporating low percentage of RB, as oil-mill by-products, is promising to partly replace UF resin in the wood industry, minimising formaldehyde emission or toxic gasses during board formation.

The purpose of this research paper focused on studying the role of activated carbons (ACs), which were synthesized from long-chain aldehyde-based xerogels (Xs-AC), as benefit additives to enhance the application of a low-cost urea formaldehyde (UF) adhesive for production of rice straw (RS) composites complying with both the standard specifications of particle-board type and the board produced from using conventional adhesive of RS fibers (methylene diphenyl diisocyanate, MDI). The results are supported by differential scanning calorimetry (DSC) analysis, which indicated the curing and interaction of RS fibers with the adhesive systems.

RS-based composites of particle-board type were prepared from applying new Xs-AC–UF adhesive systems to RS particles. For comparison, particle boards by using commercial UF and 4 per cent MDI were also prepared. To clear the beneficial effect of X-ACs as new HCHO (formaldehyde)-scavengers, the properties of the resulted boards were compared with those produced from the previous investigated scavenger: amide-containing starch-UF (AM/St–UF), and treated RS. DSC analysis was performed on the RS adhesive system, to follow the curing and the interaction behavior of UF with fibers in the presence of Xs-ACs.

The promising results obtained of RS particle boards from using the investigated new HCHO-scavenger are modulus of rupture (MOR) = 17.2 MPa, modulus of elasticity (MOE) = 4,689 MPa and internal bond (IB) strength = 0.49 MPa. While, the thickness swelling (TS) and maximum reduction in free-HCHO are 48.5 and 44.6 per cent, respectively; this reduction value specified the particle-board of E1-E2 type.

The X-AC-UF adhesive systems and treated RS provided particle boards with mechanical properties (MOR, MOE and IB) that met the standard specification values (class M-2 according to ANSI standard and P-2 according to EN standard requirements), together with maximum reduction in toxicity of UF. However, the resistance in water swelling property is weak and needs further study to be solved.

The incorporation of small percentage of new HCHO-scavenger (X-AC) to UF is an effective way to improve its thermal behavior. Moreover, the mechanical properties of agro-based composites based on the treated RS waste together with the X-AC-UF system exceeded those values of panels produced from (AM/St-UF) and also from (4 per cent MDI).

Incorporating the Xs-AC to commercial UF will be of benefit for saving the health of wood co-workers and motivating the wood mill to export its wood products, as well as minimizing the export of MDI.

This paper was based on enhancing the potential utilization of both undesirable RS agro wastes and environmentally unacceptable low-cost UF adhesive in the production of agro-composites that comply with the International Standard Specifications of particle board type. In this respect, a new HCHO-scavenger was synthesized and applied, based on AC from non-conventional xerogels. This study presents a solution to protect the environment from pollution, as a result of burning the undesirable RS, as well as to protect the workers and users of wood panels from exposure to the toxic and carcinogenic gas (formaldehyde). It also benefits in replacing the high cost of the RS adhesive (MDI) by using low-cost modified UF.

The purpose of this paper is to examine the effects of denaturised rice bran (RB) and route of its incorporation during synthesis of urea-formaldehyde adhesive, on the performance of the resulting adhesive, especially viscosity, free-formaldehyde (HCHO) and quality of the produced bagasse-based composites, in comparison with those produced from commercial urea formaldehyde (UF) and RB-added UF.

The experiments were carried out using different denaturised RB at different percentages (1-5 per cent) and pH’s (9-11 per cent). These denaturised RB were incorporated at the last synthesis stage of UF synthesis process. The assessment was carried out on both the viscosity and environmental safety of the adhesive system, as well as the quality of the manufactured bagasse-based composites, of the particleboards (static bending, internal bond (IB) strength and water resistance properties), in comparison to commercial UF and RB added to UF. The performance of the adhesive system was evidenced by the thermogravimetric analysis and differential scanning calorimetry analyses.

The results showed that maximum static bending [modulus of rupture (MOR) and modulus of elasticity (MOE)], IB strength and water resistance properties of the resulted wood product accompanied the incorporating 5 per cent of the denaturised RB (pH = 9.0), at the last synthesised stage of UF synthesis process. Where, this synthesis process provided adhesive with viscosity nearly approaching to commercial UF adhesive, and reduced the free-HCHO of adhesive and board by approximately 56 and 49 per cent, respectively. For mechanical and water resistance properties, it provided board with 24.5 MPa MOR, 3,029 MPa MOE, 0.64 MPa IB, 11 per cent swelling (SW) and 20.5 per cent absorption. These properties fulfil the requirements of high grade particleboards American National Standard Institute (ANSI) A208.1, especially with respect to static bending values and water swelling property.

Incorporating 5 per cent of pre-denaturised RB, at pH 9.0, in wet form, and in the last stage of synthesis UF, provided adhesive system with convenient viscosity together with lower free-HCHO and acceptable board properties, compared with that produced from commercial UF, or adding denaturised RB to already synthesised UF. For the mechanical (MOR, MOE and IB) and water resistance properties (SW per cent and absorption per cent) of the produced composite are complied the standard values of H-3 grade of particleboard.

Promising adhesive system is resulted from incorporating 5 per cent of pre-denaturised RB at pH 9.0, in wet form, during last stage of UF synthesis process.

Incorporating the RB by-product of oil production to commercial UF or during synthesis of UF will be benefit for saving the healthy of wood co-workers, and motivating the wood mill to export its wood products.

The article provides a potential simple way to solve the drawback of increasing the viscosity of UF, as a result of adding RB, via incorporating the RB during synthesis process. The viscosity of the synthesised RB-modified UF approaches RB-free UF, and consequently the adhesive system easily penetrates through agro-fibres, and provides good bonding behaviour and high performance wood product (both quality and environmental by minimising formaldehyde emission or toxic gasses during board formation).

The purpose of this paper is to study the possibility of preparing high performance, agro‐based composites from rice straw, using eco‐polyalcohol polymers‐based adhesive system. The utilization of rice straw (undesirable biowastes) for the production of high quality biocomposite products, will add economic value, help to reduce the environmental impact of waste disposal and, most importantly, provide a potentially inexpensive alternative to the existing commercial artificial wood‐panels.

Simple synthesizing and optimizing the polyalcohol polymers‐based non‐toxic adhesive system were carried out, by blending corn starch, as natural polyalcohol polymer with polyvinyl alcohol, as synthetic polyalcohol polymers‐based adhesive (St/PV adhesive), at temperature ∼75°C. The percentages of adhesive components, type of starch, bonding temperature and time were optimized. Assessment of the synthesized adhesive was performed from its adhesion behavior (bond strength), in comparison with commercial thermosetting resin (urea‐formaldehyde), as well as the properties (mechanical and physical properties) of the composites produced. The effects of amount and type of water resistance co‐additives (paraffin wax and polyester), on mechanical properties of RS‐based composite were also optimized.

The promising adhesive system exhibits improved performance over a previously commercially HCHO‐based adhesive (UF), and results bonding strength 9.8 N/mm2, as well as MOR, IB and TS of RS‐based composites up to 31 N/mm2, 0.49 N/mm2 and 20%, respectively.

Through the studied eco‐adhesive with relatively high natural polyalcohol polymer (starch) in presence of water‐resistance additive (PE) provided a good bonding strength and comparative RS‐based composite properties, with that produced from commercial UF. For the mechanical properties (MOR and IB) are complied the standard values; while water resistance is still higher. Further study is needed to solve this problem.

The approach provided a HCHO‐free adhesive with good bonding strength, comparative board strength and water resistance, reasonable working life, and without formaldehyde emission. Starch‐based adhesive with low percentages of polyvinyl alcohol is considered a promising inexpensive alternate adhesive in wood industry based on rice straw wastes, which traditionally required expensive pMDI.

The paper provides a potential way to utilise undesirable rice by‐product (RS), corn starch as industrial raw material. This will benefit farmers significantly. Meanwhile, the modified starch adhesive with low percentage of PVA is promising to partly or completely replace urea formaldehyde resin and pMDI that are mainly used in wood industry, or pMDI in RS‐based artificial wood, avoiding formaldehyde emission or toxic gases during exposed to burning, and reducing the dependence on petroleum products.

In the recent years, the industries show interest in natural and synthetic fibre-reinforced hybrid composites due to weight reduction and environmental reasons. The purpose of this experimental study is to investigate the properties of the hybrid composites fabricated by using carbon, untreated and alkaline-treated hemp fibres.

The composites were tested for strengths under tensile, flexural, impact and shear loadings, and the water absorption characteristics were also observed. The finite element analysis (FEA) was carried out to analyse the elastic behaviour of the composites and predict the strength by using ANSYS 15.0.

From the experimental results, it is observed that the hybrid composites can withstand the maximum tensile strength of 61.4 MPa, flexural strength of 122.4 MPa, impact strength of 4.2 J/mm² and shear strength of 25.5 MPa. From the FEA results, it is found that the maximum stress during tensile, flexural and impact loading is 47.5, 2.1 and 1.03 MPa, respectively.

The results of the untreated and alkaline-treated hemp-carbon fibre composites were compared and found that the alkaline-treated composites perform better in terms of mechanical properties. Then, the ANSYS-predicted values were compared with the experimental results, and it was found that there is a high correlation occurs between the untreated and alkali-treated hemp-carbon fibre composites. The internal structure of the broken surfaces of the composite samples was analysed using a scanning electron microscopy (SEM) analysis.

The purpose of this paper is to describe how lignosulphonate modified ketone formaldehyde resins containing functional groups such as hydroxyl, carbonyl, phenol, were produced via in situ modification of ketone/formaldehyde resins. Cyclohexanone‐formaldehyde (CF‐R), acetophenone‐formaldehyde (AF‐R) and methyl ethyl ketone‐formaldehyde (MEKFR) resins were in situ modified with lignosulphonate in the presence of sodium hydroxide. The paper reports the synthesis of lignosulphonate‐modified resins with a one step method of in situ modification of ketonic resin. The roles of the types of the ketone, lignosulphonate concentration, the solubility, molecular weight and thermal properties of the product were investigated.

Ketone, formalin (37 per cent aqueous solution), lignosulphonate were mixed and 20 per cent aqueous NaOH solution was added to produce the resin.

There was improvement of the properties of the lignosulphonate modified ketonic resins produced from waste black liquor. The lignosulphonate modified ketone‐formaldehyde resins were soluble in common organic solvents.

The reaction mixture must be stirred continuously. Subsequently, 37 per cent formalin was added dropwise in total while refluxing. The amount of aqueous NaOH solution is limited since the formed resin may become insoluble in common organic solvents. The water was removed from MEKFR, successively by evaporating with rotary evaporator.

This study provides the application of ketonic resins. The modified ketonic resins containing lignosulphonate groups may also promote the adhesive strength of a coating. The cell walls of various cell types of plants, for example, wood fibres, vessels, and tracheid, have lignin as an important constituent. It constitutes 20‐30 per cent of the weight of wood.

Lignosulphonate modified ketonic resins have been synthesized in the presence of a base catalyst. These resins have higher Tg or Tm values and molecular weight than CFR and AFR alone and also have thermoset property. Environmental and ecological concerns have increased the attention paid by the chemical industry to renewable raw materials.

The study examined the influence of environmental standards set by the SME agro-based processing firms and farmers' environmental empowerment on farmers' adoption of environmentally friendly agricultural practices; and the mediating role of empowerment on the relationship between SME agro-based processing firm environmental standards and farmers' adoption of environmentally friendly agricultural practices.

Data was collected from purchasing managers of the agro-based processing firms. The SPSS software, SMART PLS and CB-SEM software were used to obtain results on the influence of environmental standards set by the SME agro-based processing firms on adoption of environmentally friendly agricultural practices; the influence of farmers' environmental empowerment on adoption of environmentally friendly agricultural practices and the mediating role of farmers' environmental empowerment on the relationship between SME agro-based processing firm environmental standards and farmers' adoption of environmentally friendly agricultural practices.

Findings indicated that SME agro-processing environmental standards have an influence on farmers' adoption of environmentally friendly agricultural practices. Empowering farmers in environmental issues influenced their adoption of environmentally friendly agricultural practices. A partial mediation effect was observed on testing the mediating role of farmers' environmental empowerment on the relationship between SME agro-based processing firm environmental standards and farmers' adoption of environmentally friendly practices.

The study mainly focused on the upstream part of agricultural supply chains. The research has implications to decision-makers in government concerned with enhancing environmentally friendly practices among farmers in general.

The influence of SME agro-based processing firm environmental standards on farmers' adoption of environmentally friendly agricultural practices; the influence of farmers' environmental empowerment on farmers' adoption of environmentally friendly practices; and the mediating role of farmers' environmental empowerment on the relationship between SME agro-based processing firm environmental standards and farmers' adoption of environmentally friendly agricultural practices are aspects that have not been given significant attention.

Using firm-level data from small- to micro-sized agro-based enterprises located in developing Africa, the purpose of this paper is to employ a resource-based marketing model to explain financial and nonfinancial organizational performance outcomes. The moderating effect of firm size on the structural inter-linkages between customer retention orientation, eBrand promotion and the organizational performance outcomes is also explored.

Partial least squares path modeling approach was the analytical method for data analysis purposes.

The data support the assumption that marketing resources as well as the moderating influence of firm size play a strong role on the agro-based enterprise performance.

This study widens the context of inquiry on agro-based enterprise performance to include developing economies in Sub-Saharan Africa. The value of the paper rests in its intent to offer small- to micro-sized agro-based businesses in emerging markets more practical ways to enhance their performance.

With focus on Uganda, this study assessed the factors influencing agro-food micro, small and medium enterprises (MSME) innovations. Kampala, Wakiso, Mukono and Jinja districts were the locations of the research.

Primary cross-sectional data was collected using structured questionnaire for a sample of 521 agro-food MSMEs in Uganda. Descriptive statistics, exploratory factor analysis and hierarchical regression analysis were used to examine the data in SPSS.

The findings indicate that MSME innovation levels were usually high, at roughly 80%. The presence of rules that encourage innovation and reward creative people would enhance innovation that is customer-focused. On the other hand, policies and principles that encourage innovation and the conduct of internal product and process improvement research would promote system-focused innovation.

Encouraging agro-food MSMEs to develop policies that support innovation would improve the overall level of innovation, while building the capacity of agro-food MSMEs to conduct product and process improvement research would increase the level of systems-focused research.

This study assessed the drivers of innovation in agri-food MSMEs in a developing country. The uniqueness of this study is in assessing the effects of innovation support services on customer-focused and systems-focused innovations.