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These are made by the reaction of phenols, formaldehyde and primary amines which at elevated temperatures (400 °F (200 °C)) undergo ring–opening polymerisation forming polybenzoxazine thermoset networks; when hybridised with epoxy and phenolic resins the resulting ternary systems have glass transition temperatures in excess of 490 °F (250 °C).
Bakelite was produced for the first time in 1872 by Adolf von Baeyer, though its use as a commercial product was not considered at the time. [6]Leo Baekeland was already wealthy due to his invention of Velox photographic paper when he began to investigate the reactions of phenol and formaldehyde in his home laboratory.
The Dutch painting forger Han van Meegeren mixed phenol formaldehyde with his oil paints before baking the finished canvas, in order to fake the drying out of the paint over the centuries. [citation needed] Atmospheric re-entry spacecraft use phenol formaldehyde resin as a key component in ablative heat shields (e.g. AVCOAT on the
Most plastic coatings in the packaging industry are polyethylene and to a much lesser degree PET. Liquid packaging board cartons typically contain 74% paper, 22% plastic and 4% aluminum. Frozen food cartons are usually made up of an 80% paper and 20% plastic combination. [8] The most notable applications for plastic-coated paper are single use ...
Paper Coating 1) The paper or board 2) The first layer of coating to even out the surface 3) A second layer for an even smoother and whiter surface. Pigments that absorb in the yellow and red part of the visible spectrum can be added. As the dye absorbs light, the brightness of the paper will decrease, unlike the effect of an optical ...
Lastly, plasma coating is where material is coated to the surface in the form of a thin film. Plasma coating can be used to add hydrocarbons to surfaces which can make a surface non-polar or hydrophobic. The specific type of plasma coating used to add hydrocarbons is called plasma enhanced chemical vapor deposition process or PCVD. [7]
These compounds are also used as building-block chemicals in making fragrances, thermoplastic elastomers, antioxidants, oil field chemicals, and fire retardant materials. As plastizers and antioxidants, alkylphenols are also found in tires, adhesives, coatings, carbonless copy paper and high performance rubber products.
Substrates containing two phenols (or an aniline and a phenol; see equation (8) below for a related example), undergo oxidative coupling in the presence of hypervalent iodine(III) reagents. Coupling of both the ortho and para positions is possible; however, the use of bulky silyl-protected phenols provides complete selectivity for para coupling ...