The Impact of Different Dosage of Additives on the UF Resin Used in Plywood

2011 ◽  
Vol 197-198 ◽  
pp. 147-150 ◽  
Author(s):  
Wei Wang ◽  
Li Bin Zhu ◽  
Ji You Gu ◽  
Xiang Li Weng ◽  
Hai Yan Tan

Through the study of the effects of different dosage of additives on the properties of urea formaldehyde resin adhesive prepared at low mole ratio of formaldehyde/urea, optimize the synthetic process of the UF resin which is used at the E0 grade plywood. The results showed that the product synthesized under the following condition: the mole ratio of formaldehyde/urea is 0.99:1, the dosage of the specific additive is 1.0% and that of melamine is 3-4%, had a good comprehensive performance and the formaldehyde emission of the plywood meets the E0 grade which is environmental-friendly.

2012 ◽  
Vol 621 ◽  
pp. 79-82
Author(s):  
Gui Hua Chen ◽  
Jian Han ◽  
Xiao Huan Zhang

This study aimed at exploring a producing method of urea-formaldehyde resin that contained low free formaldehyde. Effects of the pH value of addition stage, the pH value and the temperature of polycondensation stage on the properties of the resin were analyzed. The experimental results showed that controlling the pH value of addition stage to 7.5-8.0, regulating the pH value of polycondensation stage to 4.8-5.1, and keeping the temperature of polycondensation stage to 88-92°C, a low toxic urea-formaldehyde resin adhesive was obtained which contained free formaldehyde 0.08%. Using this resin adhesive, the bonding strength of the plywood reached 1.7MPa, formaldehyde emission of the plywood was 0.7mg/l, reaching the grade E1.


RSC Advances ◽  
2021 ◽  
Vol 11 (40) ◽  
pp. 25010-25017
Author(s):  
Li Lu ◽  
Yan Wang ◽  
Tianhua Li ◽  
Supeng Wang ◽  
Shoulu Yang ◽  
...  

Reactions between CaCO3 and CH2O2 during polycondensation of UF resin produce Ca2+. Ionic bond complexation binds Ca2+ with UF resin. The UF resin crystalline percentage decreases from 26.86% to 22.71%. IB strength of resin bonded fiberboard increases from 0.75 to 0.94 MPa.


2018 ◽  
Vol 69 (3) ◽  
pp. 247-252
Author(s):  
Timuçin Bardak ◽  
Eser Sozen ◽  
Kadir Kayahan ◽  
Selahattin Bardak

RSC Advances ◽  
2021 ◽  
Vol 11 (52) ◽  
pp. 32830-32836
Author(s):  
Kazuki Saito ◽  
Yasushi Hirabayashi ◽  
Shinya Yamanaka

This is the first experiment to demonstrate that GO effectively prevents formaldehyde emission from UF resin.


2011 ◽  
Vol 71-78 ◽  
pp. 3170-3173
Author(s):  
Ji Zhi Zhang ◽  
Xiao Ying Liu ◽  
Ying Ying Qiu ◽  
Xiao Mei Wang ◽  
Jian Zhang Li ◽  
...  

Urea-formaldehyde resin was modified by a modifier with different synthetic processes labelled as UFM1, UFM2, and UFM3 respectively. As a comparison, normal UF resin with a F/U molar ratio of 1.1 labelled as UF0 was synthesized. The thermal behavior of modified urea-formaldehyde resins was studied by TG-DTA techniques, and the properties of plywood bonded with the UFM resins were investigated. The conclusions were as follows: (1) the modifier used in this study could significantly reduce the free formaldehyde content of urea-formaldehyde resin and the formaldehyde emission of plywood; (2) The exothermic peak temperatures of DTA curve were 129.37, 125.05, 120.98, and 116.11 °C for UF0, UFM1, UFM2, and UFM3 respectively. (3) The plywood manufactured with UFM2 and UFM3 resins have high bonding strength (1.28MPa and 1.59MPa) and low formaldehyde emission value (E1 grade).


2013 ◽  
Vol 774-776 ◽  
pp. 1232-1236
Author(s):  
Nan Zhe Zhang

In order to prepare urea-formaldehyde (UF) resin adhesive with good performance for glass wool products, we used polyvinyl alcohol (PVA), p-toluenesulfonamide (PTSA) and methanol to modify UF resin, optimized the molar ratio of formaldehyde (F) / urea (U) and reaction components ratio by orthogonal test, reduced the content of free formaldehyde in UF resin, and enhanced the water resistance, flexibility and stability of UF resin.


2013 ◽  
Vol 562-565 ◽  
pp. 846-851
Author(s):  
Hao Zhang ◽  
Ying She ◽  
Shu Ping Song ◽  
Jun Wen Pu

Nanocrystalline cellulose (NCC) was used for improving the formaldehyde (HCHO) emission and bonding strength of urea formaldehyde (UF) resin adhesive in fiberboard and plywood. The original NCC was modified by 3-aminopropyltriethoxysilane (APTES) and the wetting property with UF resin adhesive was improved by 26.4%. The UF resin adhesive with modified NCC was characterized by X-ray powder diffraction (XRD), thermogravimetric analysis (TG) and Fourier transform infrared (FT-IR). The crystal region of UF resin adhesive was influenced by NCC and the diffraction intensity of the peak at 2θ = 22.82° was enhanced significantly. The thermal stability of UF resin adhesive with 1.0% modified NCC increased by 4.9%. And modified NCC led hydroxyl groups into the UF resin adhesive. HCHO emission and bonding strength of the UF resin adhesive with modified NCC were tested according to Chinese National Standards GB/T 17657-1999 and GB/T 9846-2004. The HCHO emission of fiberboard and plywood with 1.5% modified NCC decreased by 13.0% and 53.2%, respectively. The bonding strength of fiberboard increased by 158.3% (from 0.12 MPa of control group to 0.31 MPa of fiberboard with 1.5% modified NCC), while 1.5% modified NCC led to a 23.6% increase in the plywood.


RSC Advances ◽  
2016 ◽  
Vol 6 (16) ◽  
pp. 12850-12861 ◽  
Author(s):  
Y. Zhang ◽  
Z. B. He ◽  
L. Xue ◽  
D. M. Chu ◽  
J. Mu

To investigate the influence of urea–formaldehyde resin (UF resin) adhesive on the thermal utilization of wood waste, the pyrolysis of particleboard and its main components (poplar and UF resin) are studied in this paper.


2012 ◽  
Vol 490-495 ◽  
pp. 3476-3480 ◽  
Author(s):  
Zhen Zhong Gao ◽  
Chao Yue ◽  
Hai Bo Cao ◽  
Xiao Bo Wang ◽  
Xiao Feng Zhu ◽  
...  

Low formaldehyde emission and high bonding strength were two basic criterions of a good urea-formaldehyde resin adhesive (UFRA). In our study, melamine modified methylolurea solution (MUS), was synthesized and used as modifier for UFRA. The bonding strength and formaldehyde emission of urea-formaldehyde resin adhesives(UFRA) were influenced by some factors such as F/U molar ratio of the main resin, F/U molar ratio of modifier, melamine content, mixing ratio of main resin with modifier, which were investigated by a series of single-factor experiments. The results showed that the best adhesive bonding strength of UFRA was 0.93MPa and the lowest formaldehyde emission was 0.43mg / L, when F/U molar ratio of the main resin was 1.5, F/U molar ratio of the MUS was 0.5, the mass fraction of melamine addition level was 5wt.% of MUS, and the mixing mass ratio of methylolurea solution (MUS) to the main UF resin was 20:80.


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