Resin - Nonconvertible resins
1. Cellulose Ester
Some of the cellulose ester are cellulose acetate, cellulose acetate butyrate (CAB), and cellulose acetate propionate (CAP).
Cellulose acetate is the simplest organic cellulose ester, offers excellent properties in coating films (e.g., flame resistance, high melting point, toughness, and clarity).
2. Nitrocellulose
Nitrocellulose is an outstanding film-forming substance which displays rapid solvent evaporation (short drying time). Nitrocellulose is the common name for the nitration product of cellulose. It is derived from cellulose, a material from plants, and therefore a renewable source. The commercial product is made by reacting cellulose with nitric acid.
Soluble nitrocellulose has a unique combination of properties such as toughness, durability, solubility, gloss, and rapid solvent release. The most important areas of use of nitrocellulose lacquers are for coating wood, metal (e.g., automotive repair), paper, foil (cellophane, aluminum), leather,and textiles and in nail polish.
3. Chlorinated Rubber
Chlorinated rubber (CR) is manufactured by using natural or synthetic rubber such as polyethylene, polypropylene or polyisoprene which is degraded to low molecular mass compounds by mastication or addition of radical formers and dissolved in carbon tetrachloride (CTC). Chlorine contents are typically 64-68 wt %. Chlorine gas is introduced into this solution and reacts with the raw material to form CR. The solution is then introduced into boiling water. The CR is precipitated, and the solvent vaporizes. The CR is separated from water, rinsed, dried and ground to form a white powder which is the saleable product.
The main area of use of chlorinated rubber paints is for underwater coatings on ships. Favorable properties for this application are high water resistance, rapid drying, good mutual adhesion of the individual layers, and the fact that old coats of paint can easily be renewed.
4. Vinyl resins
Vinyl resins are synthesized by polymerization of monomers that contain CH2=CH groups.
Paints and coating materials based on vinyl resins are generally physically drying.
Vinyl resins are include polyolefins, poly(viny1 halides) and vinyl halide copolymers, poly(viny1 esters), poly(viny1 alcohol), poly(viny1 acetals), poly(viny1 ethers), and polystyrene.
Mar 30, 2010
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