Types of chemical paint remover Paint stripper

1 types of chemical paint remover

1.1 caustics
1.2 solvents
1.3 other components

types of chemical paint remover

chemical paint removers work on types of finishes, , when multiple types of finishes may have been used on particular surface, trial , error testing typical determine best stripper each application. 2 basic categories of chemical paint removers caustic , solvent.

caustics

caustic paint removers, typically sodium hydroxide (also known lye or caustic soda), work breaking down chemical bonds of paint, hydrolysis of chain bonds of polymers forming paint. caustic removers must neutralized or new finish fail prematurely. in addition, several side effects , health risks must taken account in using caustic paint removers. such caustic aqueous solutions typically used antique dealers aim restore old furniture stripping off worn varnishes, example.

solvents

solvent paint strippers penetrate layers of paint , break bond between paint , object swelling paint.

the principal active ingredient in historically common solvent paint strippers dichloromethane, called methylene chloride, has serious health risks including death, carcinogen, , other risks.

solvent strippers may have formulations orange oil (or other terpene solvents), n-methylpyrrolidone, esters such dibasic esters (often dimethyl esters of shorter dicarboxylic acids, aminated, example, adipic acid or glutamic acid), aromatic hydrocarbons, dimethylformamide, , other solvents known well. formula differs according type of paint , character of underlying surface. nitromethane commonly used solvent. dimethyl sulfoxide less toxic alternative solvent used in formulations.

paint strippers come in liquid, or gel ( thixotropic ) form clings vertical surfaces.

the principle of paint strippers penetration of paint film molecules of active ingredient, causing swelling; volume increase causes internal strains, which, weakening of layer s adhesion underlying surface, leads separation of layer of paint substrate.

other components

various co-solvents added primary active ingredient. these assist penetration paint , removal , differ according target paint. ethanol suitable shellac, methyl ethyl ketone used cellulose nitrate, , phenol , cresols employed in industrial formulas. benzyl alcohol used well.

activators increase penetration rate; dichloromethane water suitable, other choices amines, strong acids or strong alkalis. activator s role disrupt molecular , intermolecular bonds in paint film , assist weakening this. composition depends on character of paint removed. mineral acids used epoxy resins hydrolyze ether bonds. alkaline activators based on sodium hydroxide. cosolvents double activators. amine activators, alkalines weaker inorganic hydroxides, favored when substrate corroded strong acids or bases.

surfactants assist wetting surface, increasing area of solvent can penetrate paint layer. anionic surfactants (e.g., dodecyl benzenesulfonate or sodium xylene sulfonate) used acidic formulas, cationic or non-ionic suitable alkaline formulas. paint strippers containing surfactants excellent brush cleaners.

thickeners used thixotropic formulas mixture form gel adheres vertical surfaces , reduce evaporation of solvents, prolonging time solvent can penetrate paint. cellulose-based agents, e.g., hydroxypropyl cellulose, commonly used mixtures not extremely acidic or basic; under such conditions cellulose undergoes hydrolysis , loses effectiveness, fumed silica used these instead. possibility using waxes (usually paraffin wax or polyethylene or polypropylene derivatives), or polyacrylate gels.

corrosion inhibitors added formula protect underlying substrate , paint stripper storage vessel (usually steel can) corrosion. dichloromethane decomposes time hydrochloric acid, readily reacts propylene oxide or butylene oxide , therefore removed solution. chromate-based inhibitors give mixture characteristic yellow color. other possibilities include polyphosphates, silicates, borates , various antioxidants.

sequestrants , chelating agents used disarm metal ions present in solution, otherwise reduce efficiency of other components, , assist cleaning stains, contain metal compounds. common sequestrants used in paint strippers edta, tributyl phosphate, , sodium phosphate.

colorants may added.