Melamine foam is a foam-like material consisting of a Melamine resin. It is the active component of a number of abrasive cleaner sponges, notably the Magic Eraser.
In 1984, BASF launched the first commercially produced melamine resin foam, Basotect, which was originally marketed as a flame-retardant solution for soundproofing and thermal insulation in construction.
Properties
The
open-cell foam is microporous and its polymeric substance is very hard, so that when used for cleaning it works like extremely fine
sandpaper, getting into tiny grooves and pits in the object being cleaned.
On a larger scale, the material feels soft because the reticulated foam bubbles interconnect. Its structure is a 3D network of very hard strands, when compared to the array of separate bubbles in a material such as styrofoam.
Being microporous, it also effectively absorbs sound waves.
Being open-cell, it entrains countless air bubbles, giving it low thermal conductivity and thereby making it an effective insulator.
Production
Melamine foam is produced through a two-stage process: resin synthesis and curing foaming. The synthesis of melamine resin begins by dissolving melamine and
formaldehyde in a weakly alkaline solution, maintained at a pH between 8.5 and 9.0, to prevent the formation of insoluble methylene melamine precipitate. This mixture then undergoes an addition reaction at 80–90°C, forming hydroxymethyl melamine. Subsequently, hydroxymethyl melamine undergoes poly-condensation in a neutral or weakly alkaline medium, yielding melamine resin linked by dimethylene ether or methylene bonds. The second stage, curing foaming, involves thoroughly mixing the melamine resin with an
emulsifier,
curing agent, and
foaming agent. This mixture is then subjected to cross-linking via microwave or oven heating, which forms the final polymer foam with a three-dimensional network structure.
Uses
Cleaning
In the early 21st century, it was discovered that melamine foam is an effective
abrasive cleaner and the first Mr. Clean Magic Eraser was released in 2003.
Rubbing with a slightly moistened foam may remove otherwise "uncleanable" external markings from surfaces. For example, melamine foam can remove
crayon,
marker pen, and
Petroleum from painted walls and wood finishings, plastic-adhering paints from treated wooden tables, and adhesive residue and grime from
.
If the surface being cleaned is not sufficiently hard, it may be finely scratched by the melamine material. Similarly to a pencil
eraser, the foam wears away during use, leaving behind a slight residue which can be rinsed off.
Other uses
Naturally lightweight, melamine foam is also used as insulation for pipes and
ductwork, and as a soundproofing material for studios,
, auditoriums, and the like. One advantage of melamine foam over other soundproofing materials is that it's considered not flammable. Melamine foam’s fire rating is Class A/Class 1 in the United States and ULCS-102 for Canada. If heated to , the foam shrinks, and collapses.
These properties suit it as the main sound and thermal insulation material for
Shinkansen bullet trains.
Environmental impact
Recent research has highlighted that melamine sponges contribute significantly to microplastic pollution. A study published in
Environmental Science & Technology found that these sponges release over a trillion microplastic fibers globally each month due to wear and tear. These fibers can contaminate water systems and enter the food chain, posing environmental risks. The study suggests that making denser sponges and using alternative cleaning methods could mitigate this issue.
See also
External links
