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Melamine resin or melamine formaldehyde (also shortened to melamine) is a resin with melamine rings terminated with multiple hydroxyl groups derived from formaldehyde. This thermosetting plastic material is made from melamine and formaldehyde. [1] In its butylated form, it is dissolved in n-butanol and xylene. It is then used to cross-link with ...
Urea-formaldehyde resins are widely used as the matrix binder in construction utility products such as particle board, wafer board, and plywood, which are true particulate and laminar composite structures. Melamine-formaldehyde resins are used for plastic laminating. Urea-formaldehyde resin condensates Cured melamine resin structure
Melamine also is used in the fabrication of melamine polysulfonate, used as a superplasticizer for making high-resistance concrete. Sulfonated melamine formaldehyde (SMF) is a polymer used as a cement admixture to reduce the water content in concrete while increasing the fluidity and the workability of the mix during handling and pouring. It ...
Left: individual linear polymer chains Right: Polymer chains which have been cross linked to give a rigid 3D thermoset polymer. In materials science, a thermosetting polymer, often called a thermoset, is a polymer that is obtained by irreversibly hardening ("curing") a soft solid or viscous liquid prepolymer (). [1]
In situ polymerization of such formaldehyde systems usually involves the emulsification of an oil-phase in water. Then, water-soluble urea/melamine formaldehyde resin monomers are added, which are allowed to disperse. The initiation step occurs when acid is added to lower the pH of the mixture.
With three amino substituents, melamine is a precursor to commercial resins. Guanamines are closely related to melamine, except with one amino substituent replaced by an organic group. This difference is exploited in the use of guanamines to modify the crosslinking density in melamine resins .
This model can be used to describe a system in which the monomer distribution and concentration are inhomogeneous, and is restricted to a small volume. [9] Parameters determined using the local model include the mass transfer weight, the degree of polymerization, topology near the interface, and the molecular weight distribution of the polymer ...
Adding urea to MF resins has been shown to lower the amount of free formaldehyde below the legal limit and is often used for this purpose. [1] Another complication with MF resins is the low solubility of melamine in water. [16] Because of this and the free formaldehyde content, MF resins are not used as commonly in the field of wood modification.