Thermoplastic polymers as modifiers for urea-formaldehyde (UF) wood adhesives. I. Procedures for the preparation and characterization of thermoplastic-modified UF suspensions

2003 ◽  
Vol 87 (6) ◽  
pp. 890-897 ◽  
Author(s):  
P. Rachtanapun ◽  
P. Heiden
Keyword(s):  
Urea Formaldehyde ◽  
Thermoplastic Polymers ◽  
Wood Adhesives

scholarly journals Preparation and Characterization of Bio-Oil Modified Urea-Formaldehyde Wood Adhesives

BioResources ◽  
2014 ◽  
Vol 9 (3) ◽  
Author(s):  
Ben Li ◽  
Ji-Zong Zhang ◽  
Xue-Yong Ren ◽  
Jian-min Chang ◽  
Jin-sheng Gou
Keyword(s):  
Urea Formaldehyde ◽  
Wood Adhesives ◽  
Bio Oil ◽  
Modified Urea

Characterization of particleboard made from oil heat-treated rubberwood particles at different mixing ratios

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6795-6810
Author(s):  
Nurul Fatiha Osman ◽  
Paimon Bawon ◽  
Seng Hua Lee ◽  
Pakhriazad Hassan Zaki ◽  
Syeed SaifulAzry Osman Al-Eldrus ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Oil Content ◽  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Thermal Characterization ◽  
High Dimensional ◽  
Mixing Ratios ◽  
Uf Resin ◽  
Heat Treated

Particleboard was produced by mixing oil heat-treated rubberwood particles at different ratios, with the goal of achieving high dimensional stability. Rubberwood particles were soaked in palm oil for 2 h and heat treated at 200 °C for 2 h. The treated particles were soaked in boiling water for 30 min to remove oil and were tested for chemical alteration and thermal characterization via Fourier-transform infrared spectroscopy and thermogravimetric analysis. Particleboard was fabricated by mixing treated rubberwood particles (30%, 50%, and 70%) with untreated particles (70%, 50%, and 30%, respective to previous percentages) and bonded with urea-formaldehyde (UF) resin. The results revealed that oil-heat treated particles had greater thermal stability than the untreated particles. The addition of oil heat treated particles improved the physical properties of the particleboard with no significant reduction in mechanical strength. However, this was only valid for ratios of 70% untreated to 30% treated and 50% untreated to 50% treated. When a ratio of 70% oil heat treated particles was used, both the physical and mechanical properties were reduced drastically, due to bonding interference caused by excessive oil content. Particleboard made with a ratio of 5:5 (treated to untreated) exhibited the best physical and mechanical properties.

scholarly journals Lignosulphonates as an Alternative to Non-Renewable Binders in Wood-Based Materials

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4196
Author(s):  
Sofia Gonçalves ◽  
João Ferra ◽  
Nádia Paiva ◽  
Jorge Martins ◽  
Luísa H. Carvalho ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Aromatic Ring ◽  
Phenol Formaldehyde ◽  
Urea Formaldehyde ◽  
Value Added ◽  
Wood Adhesives ◽  
Renewable Source ◽  
Pressing Time ◽  
Value Added Products ◽  
Total Market

Lignin is a widely abundant renewable source of phenolic compounds. Despite the growing interest on using it as a substitute for its petroleum-based counterparts, only 1 to 2% of the global lignin production is used for obtaining value-added products. Lignosulphonates (LS), derived from the sulphite pulping process, account for 90% of the total market of commercial lignin. The most successful industrial attempts to use lignin for wood adhesives are based on using this polymer as a partial substitute in phenol-formaldehyde or urea-formaldehyde resins. Alternatively, formaldehyde-free adhesives with lignin and lignosulphonates have also been developed with promising results. However, the low number of reactive sites available in lignin’s aromatic ring and high polydispersity have hindered its application in resin synthesis. Currently, finding suitable crosslinkers for LS and decreasing the long pressing time associated with lignin adhesives remains a challenge. Thus, several methods have been proposed to improve the reactivity of lignin molecules. In this paper, techniques to extract, characterize, as well as improve the reactivity of LS are addressed. The most recent advances in the application of LS in wood adhesives, with and without combination with formaldehyde, are also reviewed.

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