Qianyu Zhang^1,2,#, Shi Chen^1,2,#, Long Cao^1,2, Hong Lei³, Antonio Pizzi⁴, Xuedong Xi^1,2,*, Guanben Du^1,2

Journal of Renewable Materials, Vol.12, No.2, pp. 235-244, 2024, DOI:10.32604/jrm.2023.029537

Abstract Using non-toxic, low-volatile glyoxal to completely replace formaldehyde for preparing urea-glyoxal (UG) resin adhesive is a hot research topic that could be of great interest for the wood industry. However, urea-glyoxal (UG) resins prepared by just using glyoxal instead of formaldehyde usually yields a lower degree of polymerization. This results in a poorer bonding performance and water resistance of UG resins. A good solution is to pre-react urea to preform polyurea molecules presenting already a certain degree of polymerization, and then to condense these with glyoxal to obtain a novel UG resin. Therefore, in this present work, the urea was… More > Graphic Abstract

Antonio Pizzi^*

Journal of Renewable Materials, Vol.11, No.9, pp. 3403-3415, 2023, DOI:10.32604/jrm.2023.030930

Abstract This brief article reviews a very particular and quite narrow field, namely what has been done and what is needed to know for tannin adhesives for wood panels to succeed industrially. The present fashionable focus on bioadhesives has led to producing chemical adhesive formulations and approaches for tannin adhesives as a subject of academic publications. These, as good and original they might be, are and will still remain a rather empty academic exercise if not put to the test of real industrial trials and industrial use. They will remain so without the “little” secrets and techniques outlined here that show… More >

Wen Gu^#, Xinyue Ding^#, Min Tang^*, Feiyan Gong^*, Shuangshuang Yuan, Jintao Duan

Journal of Renewable Materials, Vol.11, No.8, pp. 3245-3259, 2023, DOI:10.32604/jrm.2023.027461

Abstract Biomass adhesive is conducive to decreasing the dependence of the wood adhesive industry on synthetic resin based on fossil resources and improving the market competitiveness of adhesives. It is also a critical breakthrough to realize the goal of carbon peaking and carbon neutrality in the wood industry. In this study, a full biomass wood adhesive composed of tannin and sucrose was developed and applied successfully to the preparation of plywood. The preparation technique of plywood was optimized, and the chemical structure, curing performance, crystallization property and thermal performance of the adhesive were investigated. Results showed that: (1) hot-pressing temperature played… More >

Qianyu Zhang^1,2, Antonio Pizzi³, Hong Lei^1,2,*, Xuedong Xi^1,2,*, Ming Cao^1,2, Long Cao^1,2

Journal of Renewable Materials, Vol.11, No.3, pp. 1439-1450, 2023, DOI:10.32604/jrm.2022.023535

Abstract Soy protein adhesives are currently a hot research topic in the wood panels industry for the abundant raw material reserves, reasonable price and outstanding environmental features. But their poor water resistance, low bonding strength and intolerance to mold are major drawbacks, so that proper modification before use is essential. Glutaraldehyde is one of the more apt cross-linking agents for soybean protein adhesives, which can effectively improve the bonding strength and water resistance of the adhesive. Equally, glutaraldehyde is also an efficient and broad-spectrum fungicide that can significantly improve the anti-fungal properties of a soy protein adhesive. In the work presented… More > Graphic Abstract

Claudio Del Menezzi^1,2,3, Antonio Pizzi^2,*, Siham Amirou², Xuedong Xi^4,5

Journal of Renewable Materials, Vol.11, No.2, pp. 539-553, 2023, DOI:10.32604/jrm.2022.024971

Abstract

This article presents the first applied results of using citric acid in combinations with a melamine-urea-formaldehyde (MUF) resin for bonding wood veneers. The chemical reactions involved are shown based on a MALDI ToF analysis of the reaction of the MUF resin with citric acid. The preliminary results of the physical and mechanical properties of the LVL prepared are also presented. Veneers from Populus sp were used to manufacture 5-layer laminated veneer lumber (LVL) of small dimensions. Five combinations of the amount of citric acid, MUF spread rate and pressing parameters were tested. LVL bonded with 20% of citric acid +… More > Graphic Abstract

Houda Saad^1,2,*, Antonio Pizzi^3,4, Bertrand Charrier², Naceur Ayed¹, Karsten Rode⁵, Fatima Charrier - El Bouhtoury²

Journal of Renewable Materials, Vol.3, No.1, pp. 34-43, 2015, DOI:10.7569/JRM.2014.634130

Abstract The possible use of Tunisian pomegranate tannins in wood adhesive formulation was studied for the fi rst time. Colorimetric tests, Fourier transformed infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and matrix-assisted laser desorption/ionization time-of-fl ight (MALDI-TOF) mass spectrometry were used to examine pomegranate tannins. Analysis showed that pomegranate peels are rich in hydrolyzable tannins. The Stiasny number tests showed the low reactivity of pomegranate tannin extract to formaldehyde and thus the diffi culty of using it in wood adhesive formulation. Thermomechanical analysis (TMA) and strength analysis of pomegranate tannin/hexamine-based resin showed weak bonding properties. More >

D.N. Dorr, S.D. Frazier, K.M. Hess, L.S. Traeger, W.V. Srubar III^*

Journal of Renewable Materials, Vol.3, No.3, pp. 195-204, 2015, DOI:10.7569/JRM.2015.634108

Abstract A study of the potential for gelatin-based derivatives to serve as biorenewable, biodegradable adhesives for wood and engineered wood products is presented in this article. The effect of gelatin-to-water weight percent on the mechanical, specifically ultimate breaking (bond) strength, and thermal properties was investigated using tensile testing and differential scanning calorimetry, respectively. The breaking strengths of the gelatin-based adhesives were characterized and compared to four commercially available wood adhesives. The effect of 1–5% tannin addition on the mechanical, thermal, and moisture absorption behavior of the gelatin-based adhesives was also investigated. Results show that the gelatin-based materials demonstrate 1) appropriate thermal… More >

Weixing Zhang, Chunxia He^*

Journal of Renewable Materials, Vol.10, No.12, pp. 3263-3283, 2022, DOI:10.32604/jrm.2022.020516

Abstract With the exponential growth of the computing power, machine learning techniques have been successfully used in various applications. This paper intended to predict and optimize the shear strength of single lap cassava starchbased adhesive joints for comparison with the application of artificial intelligence (AI) methods. The shear strength was firstly determined by the experiment with three independent experimental variables (starch content, NaOH concentration and reaction temperature). The analysis of range (ANORA) and analysis of variance (ANOVA) were applied to investigate the optimal combination and the significance of each factor for the shear strength based on the orthogonal experiment. The performance… More >

Jaša Saražin¹, Ida Poljanšek¹, Antonio Pizzi², Milan Šernek^1,*

Journal of Renewable Materials, Vol.10, No.8, pp. 2117-2131, 2022, DOI:10.32604/jrm.2022.019602

Abstract The curing process of two biobased adhesives: pine tanninhexamine (TH) and organosolv lignin non-isocyanate polyurethane (NIPU), suitable for interior nonstructural use, were compared with commercial urea-formaldehyde (UF) adhesive. Changes in chemical structure before and after the curing process were observed with Fouriertransform infrared spectroscopy (FTIR). The process of adhesive curing was monitored with differential scanning calorimetry (DSC) and the automated bonding evaluation system (ABES). Both DSC and ABES measurements confirmed UF as the fastest and NIPU as the slowest curing adhesive observed. Taking into account the ABES results, the optimal pressing parameters for the TH adhesive would be 4 min… More >

Ke Shi^1,2, Luyang Wang^1,2, Ruige Qi^1,2, Chunxia He^1,2,*

Journal of Renewable Materials, Vol.10, No.5, pp. 1257-1268, 2022, DOI:10.32604/jrm.2022.017891

Abstract This work was aim to prepare a packing material from natural resources to reduce the environment pollution caused by plastics. Four bio-adhesives (guar gum, sodium alginate, agar and chitosan) were combined with lotus leaf fibers to prepare degradable composites, respectively. The mechanical properties, moisture absorption profiles and the thermal conductivity of the composites were studied and the cross section morphology and the thermal properties of the composites were analyzed. The Fourier-transform infrared spectroscopy (FTIR) results showed that the polar groups such as –OH and –COO^– in bio-adhesives can form hydrogen bond with –OH in lotus leaf fibers to connect the… More >