scholarly journals Physico-Mechanical and Thermal Properties of Thermoplastic Poly(Vinyl Alcohol) Modified Thermosetting Urea Formaldehyde Resin

2021 ◽  
Vol 21 (4) ◽  
pp. 53-66
Author(s):  
Shahin Sultana ◽  
Mehedi Mannan ◽  
Md. Jaynal Abedin ◽  
Zahidul Islam ◽  
Husna Parvin Nur ◽  
...  

Abstract Urea formaldehyde (UF) resins are brittle and to improve their tensile properties poly(vinyl alcohol) (PVA) has been used to modify the UF resin. An easy improved procedure was developed to make PVA modified UF resin on the basis of conventional synthesis of UF resin. Prepolymer of UF was mixed with different weight percentages of PVA (1-5%) to synthesize modified UF resin which can be used to make adhesive for forest products. Both UF and modified UF resins were characterized by FTIR, physico-mechanical and thermal properties analyses. Modified UF resin containing 2 wt. % PVA exhibited better results than the UF.

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.


1976 ◽  
Vol 8 (1) ◽  
pp. 131-133 ◽  
Author(s):  
Hiroshi Ochiai ◽  
Sachiko Fukushima ◽  
Miyuki Fujikawa ◽  
Hitoshi Yamamura

2011 ◽  
Vol 399-401 ◽  
pp. 381-384
Author(s):  
Chun Guang Li ◽  
Bin Guo Zheng ◽  
Wei Gong Peng ◽  
Wei Tian ◽  
Rui Zhang

The biodegradable composite films were prepared from bagasse microcrystalline cellulose as filler and poly(vinyl alcohol)(PVA) as polymeric matrix. The crystallinity, the tensile properties and the thermal properties of the composites were tested. Bagasse microcrystalline cellulose was distributed in PVA films as the crystalline state. The results show that the tensile properties and thermal properties were improved with the addition of bagasse microcrystalline cellulose. When bagasse microcrystalline cellulose mass fraction was 5%, both temperature of initial decomposition and maximum weight loss rate of composite film were raised by 11.71°C and 36.86°C, and the tensile strength increased by 17.88%, and the elongation at break increased by 36.62% compared to those of pure PVA.


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.


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).


Sign in / Sign up

Export Citation Format

Share Document