Pentaerythritol Chemistry Uses(part 2)
Alkyd resin paint is esters of polybasic acids and polyhydric alcohols which have been modified by oil or fatty acids; pentaerythritol is used as a polyhydric acid. In particular, alkyd paint made with pentaerythritol has superior adhesion, weather-resistant, color, luster, water resistant and chemical resistant properties in comparison with trihydric alcohols, such as glycerin, and also dry faster than trihydric alcohols.
Almost all synthetic resin paints use oil (drying oil) and to meet with the increasing demand for such oils and offer users better quality than previously available, a number of modified synthetic drying oils can be make by chemically altering synthetic drying oil or natural oil. Pentaerythritol can be used to produce synthetic drying oils of good quality by esterification reaction with linseed oil, tung oil, or other natural drying oils, or by ester exchange and other reactions with fatty acid esters. Such synthetic drying oils dry quickly, and because they have outstanding properties, such as luster, water-resistance, alkali-resistance and flexibility, they are widely used in producing printing inks and processing paper. Ester gum (glycerin rosin ester) has been used as a vector for oil varnish, ink and other substances; the same rosin ester can be obtained by the use of pentaerythritol. Its hardness, high melting point, weather-resistance, high heat-resistance and low evaporation loss and colorization, as well as its anti-oxidizing properties, are the features in using pentaerythritol for many types of varnish enamels. Pentaerythritol and fatty acid esters give plasticity to synthetic resins. That is, pentaerythritol tetra-acetate, when used as a plasticizer for celluloses, acetates and cellulose esters, gives them improved plasticity and impact strength. Also, esters of propionic acid, butyric acid and others are used as plasticizers for cellulose and vinyl chloride. Further, tetraesters of C6-12 acids (caproic acid and peralgonic acid) improve the mechanical, electric and heat aging properties of vinyl chloride, and are of low volatility, making them plasticizers when used for vinyl chloride in those special applications. Pentaerythritol and esters of monobasic long-chain fatty acids (stearic acid, palmitic acid), depending on the degree of esterification, take various physical forms, and are used as emulsifiers in cosmetics, and for abrasives and other purposes. Monobasic fatty acid esters of pentaerythritol have outstanding characteristics as non-ionic surface active agents, and are used in softening processes for synthetic fibers and chemical fibers (acetate, vinylon, nylon) and for smoothing in various processes of synthetic textile production. Because fatty acid esters of pentaerythritol are highly stable, have a relatively high boiling point and are low in volatility, they are used as brake oil as well as lubricating oil and corrosion preventative oil in aircraft engines. If pentaerythritol is chlorinated by means of thonyl chloride and then dechlorinated, 3.3 is obtained. If this is polymerized by BF3 or other compounds, polyether is obtained. Hercules has commercialized this as pentone resin, and because it has outstanding heat-resistance, chemical-resistance and creep-resistance properties it is widely used in mining, refining, plating, papermaking and other processes in similar manner to corrosion-resistant metals, vinylidene chloride and fluoro-resins. In addition, pentaerythritol is used as the polyether material for production of hard polyurethane. Pentaerythritol forms resins by reacting with acrolein, glutaraldehyde and various aldehydes. The resins obtained have particularly good mechanical and electric properties. Pentaerythritol tetranitrate is a stable nitric ester but is sensitive to shock and is used to denotate explosives. Pentaerythritol is used as a medicine to lower blood pressure, as a tackifier in synthetic rubber manufacture, and as a stabilizer in vinyl chloride, among other uses.
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