Synthesis and Characterization of Melamine Formaldehyde Resins for Decorative Paper Applications

Abstract

Melamine-formaldehyde (MF) resins of improved environmental compatibility were synthesized at different molar ratios, temperature and pH. Five molar ratios of melamine and formaldehyde: 35:65, 36.5:63.5, 38.3:61.7, 41.1:58.9 and 42.4:58.6 were used to synthesize the corresponding resins. The prepared samples were characterized by using molecular weight determination viscometery, field emission scanning electron microscopy and thermogravimetric analysis. It was noticed that the solid content in the resin increases with an increase in pH. The maximum percentage of the solid content (51%) was obtained for pH of 8.5 and temperature range of 95-98 o C. The refractive index of the final product was found increasing with an increase of melamine concentration in the resin. A similar trend was noticed in molecular weight of the resins with an increase in monomer yield. The maximum molecular weight of 114218 was obtained from the sample synthesized with MF molar ratio of 42.4:58.6.

CO2-Philic Surfactants Structural Morphology Prerequests for CO2 Philicity for Foam Durability for EOR Applications

“…They need the Isopropyl acetate molecule as a sample. In the picture below, the red colour imitate oxygen, black represents carbon and white is used for atoms of hydrogen [7,[30][31][32][33][34].…”

Balancing the decomposable behavior and wet tensile mechanical property of cellulose-based wet wipe substrates by the aqueous adhesive

“…Therefore, based on the dual consideration of economy and environmental protection, the biomass-based (cellulose) wipes material that has a suitable wet mechanical strength (in use) and can be efficiently decomposed after using shows a new application prospect in daily use and medical application. The conventional cellulose wet wipe is generally mixed with chemical wet strength agents (such as polyacrylic ester (PAE) [ 29 , 30 ], urea-formaldehyde resin [ [31] , [32] , [33] , [34] ], etc.) to treat cellulose and increase its wet strength through formation of chemical bonds between the cellulose fibers after heating and drying [ 35 , 36 ].…”

Stability of melamine‐formaldehyde (MF) resin under different pH and ionic strength values

“…The melamine is used as a reactive intermediate for the manufacturing of MF resins. The reaction conditions including time, temperature, formaldehyde/melamine (F/M) ratio, pH, and catalyst may influence the composition and structure of the resin that makes up the adhesive (Ullah et al, 2015).…”

“…MF resins are also used in a number of applications as an industrial adhesive, for example, in paper laminates and in dinnerware. (Anil & Vimal, 1990; Dipak, Amit, & Bhavi, 2006; Park & Jeong, 2010; Ullah et al, 2015). At high temperature, melamine is formed by the decomposition of methylolamine (Merline, Vukusic, & Abdala, 2013; Ullah et al, 2014).…”

“…The rate of methylene to ether bridges determines considerably the stability of MF particles. Ether bridges can be hydrolyzed with addition of acid and break, while methylene bridges cannot (Gao et al, 2001; Ullah et al, 2015).…”