Paint stripper, methylene chloride

Paint strippers -methylene chloride use [CHLOROCARBONS AND CHLOROHYDROCARBONS - METHYLENE CHLORIDE] (Vol 5)... 

Eor use in paint strippers, one of its first appHcations, methylene chloride is blended with other chemical components to maximi2e its effectiveness against specific coatings. Typical additives include alcohols, acids, amines or ammonium hydroxide, detergents, and paraffin wax. Paint stripping formulations without methylene chloride have not as yet been shown to be as effective as those with methylene chloride. 

A liquid not considered flammable may still have an explosive potential. An example is dichloromethane or methylene chloride, often used in paint strippers, which evaporates very quickly. It is not flammable, but its vapors may be explosive (explosive limits 12% to 22%). 

Paint strippers are also formulated to have high viscosity, otherwise they run off vertical surfaces and thereby fail to penetrate or solubilise the paint to which they have been applied. Hydroxypropyl methylcellulose is the main thickener for paint strippers, which use methylene chloride (dicldoromethane) as the principal component. Hydroxypropyl methylcellulose is useful for this purpose because it is soluble in the orgaiuc component but is not sensitive to the presence of any water that may also be present in the paint stripper. 

Also known as DCM or dichloromethane. Often used as an adhesive solvent for acrylics. Pure DCM can be found in craft stores. DCM must be distilled first from all non-flammable paint strippers beforehand (they contain a paste that holds several unwanted substances.) The paint stripper may also contain methanol (most marine grade paint strippers are 80-90% DCM. Methanol is also an organic solvent. DCM distills at 47° C or 116° F. Pure DCM is best. May cause cancer and blindness. Take necessary precautions. Methylene chloride sinks to the bottom of the jar. 

In addition to tobacco smokers, individuals who have had previous exposure to materials containing methylene chloride, such as degreasers, solvents, paint removers, and furniture strippers, are at greater risk because of an existing body burden of carbon monoxide. Approximately one-fourth to one-third of inhaled methylene chloride vapor is metabolized in the liver to carbon monoxide. In addition, methylene chloride is readily stored in body tissue. This stored material is released over time and results in elevated levels of carbon monoxide for extended periods, in some cases more than twice as long as compared with direct carbon monoxide inhalation. 

Methylene chloride-based paint strippers Other inhibitors include antimycin (cytochrome We ), doxorubicin (CoQ), and oligomydn (Fp). 

Toxicity. Methylene chloride is widely used in paint strippers and several non-fatal and fatal cases of accidental inhalation have been reported. The maximum permissible atmospheric concentration is 200 ppm and the temporary estimated acceptable daily intake is up to 500 pg/kg. 

In a fatality involving the accidental inhalation of a paint stripper containing methylene chloride, the following postmortem tissue concentrations were reported blood 510 pg/ml, brain 248 pg/g, liver 144 pg/g (J. Bonventre t fl/., J. analyt. Toxicol., 1977,1, 158-160). 

Finally, another halogenated solvent that causes toxic effects after acute exposure is dichloromethane or methylene chloride. It is used for degreasing engines and metalwork, and is the main constituent of paint stripper. If it is used in confined, enclosed spaces, such as rooms without adequate ventilation, it can lead to serious, unexpected toxic effects. As the solvent is breathed in by the worker it becomes localized in body fat. Later the... 

The use of paint stripper may lead to damage to the skin from both the sodium hydroxide (caustic soda) and the solvent, methylene chloride. Another, more serious hazard from the paint stripper is the danger of using it in a confined space and inhaling the solvent fumes. Apart from the... 

Methylene chloride is used in industry as a degreasing solvent and is found in most paint strippers. When used in a poorly ventilated or confined place, the volatile chemical is inhaled and rapidly absorbed from the lungs into the blood, which then distributes it to other areas of the body. Due to the way the circulatory system is organized the first organ exposed after the heart will be the brain, and this type of solvent, which is soluble in fat, can easily enter the brain. If sufficient levels are absorbed, the person exposed may suffer from the effects of the solvent on the brain they will feel giddy or unsteady, or even lose consciousness (narcosis). Much of the solvent will be distributed by the blood to places in the body where fat is stored, while the remainder is exhaled from the lungs. After exposure to the solvent has ended, the methylene chloride wiU start to emerge from the fat, where it was deposited earlier, and to appear in the blood. 

Trichloroethylene and 1,1,1-trichloroethane are used in correction fluids, dry-cleaning products, degreasing sprays, and solvents and spot removers. Bromochlorodifluoro-methane is a compound found in halon fire extinguishers that is abused. Freon is used for refrigeration and air conditioning systems. Anesthetics include halothane, chloroform, and the local anesthetic ethyl chloride. Methylene chloride is a component of rubber cement, paint strippers, and degreasing agents, and fluorocarbons are present in many types of aerosol sprays. 

Commercial and military paint strippers (replacing methylene chloride)... 

Methylene chloride is a widely used industrial chemical with reported atmospheric emissions of more than 126 million pounds annually in the United States. The principal route of exposure for the general population to methylene chloride is by inhalation. Occupational and consumer exposure to methylene chloride commonly occurs from spray painting and contact with consumer products such as paint strippers or aerosol cans, that contain methylene chloride. Exposures may occur as a result of breathing the vapors given off by the product or from direct dermal contact. Occupational exposure to methylene chloride by the inhalation route offers the most opportunity for exposure but it can also be absorbed through the skin. 

Halogenated Chloroform, 1,1,1-trichloroethane, trichloroethylene, methylene chloride, p-dichlorobenzene Pesticides dry-cleaning solvents aerosol propellants degreasing agents paint strippers... 

Proposition 65 s warning requirement has provided an incentive for manufacturers to remove listed chemicals from their products. For example, trichloroethylene, which causes cancer, is no longer used in most correction fluids reformulated paint strippers do not contain the carcinogen methylene chloride and toluene, which causes birth defects or other reproductive harm, has been removed from many nail care products. In addition, a Proposition 65 enforcement action prompted manufacturers to decrease the lead content in ceramic tableware and wineries to eliminate the use of lead-containing foil caps on wine bottles. 

Methylene chloride is a common ingredient of paint strippers. On a house, an alternative is to heat with a heat gun, then scrape off the paint with a putty knife. Other solvents are needed for stripping finishes from furniture. Epidemiological work suggests that methylene chloride can cause cancer of the liver, bile duct, and brain.214 It is possible that a professional furniture refinisher could be hired to remove the finish by ultrasonic cleaning or bombardment with particles. Further work is needed. 

Methylene chloride is a volatile, colorless, nonflammable liquid. It is slightly soluble in water and miscible with many other solvents, such as acetone, chloroform, carbon tetrachloride, and alcohol. Under speciflc conditions it may burn. Its commercial formulations for paint stripping are particularly flammable. Methylene chloride is a widely used solvent where quick drying (i.e., high volatility) is required. Such application areas include adhesives, cellulose acetate flber production, blowing of polyurethane foams, and metal and textile treatment. It dissolves oils, fats, waxes, many plastics, bitumen, and rubber. This property is used in paint stripper formulations. It is used as an aerosol solvent, and for extraction operations in the pharmaceutical industry. It was previously used in fire-extinguishing products. ... 

The exposure to a chemical product also depends on its physical state and the physical/chemical properties of the component chemicals. Use of paint strippers in a basement may result in exposures to the volatile methylene chloride ten times in excess of the recommended TLV (200 ppm) (82). A chemical used as a floor-tile colorant, however, will be much more stable. Each use must be considered separately with regard to its potential for occupational, general population, and environmental exposure. 

Methylene chloride (dichloromethane, methylene dichloride) n. CH2-CI2. A low-boiling chlorinated hydrocarbon which is a colorless, fairly dense, non-flammable liquid used as a solvent for cellulose triacetate and vinyl resins, a solvent in the polymerization of polycarbonate resins, and as a reactant for certain phenolic resins. It was widely used as a paint stripper and solvent for cured epoxy resins, but is less used now in the effort to keep chlorinated solvents... 

Methylene chloride (MC) is a solvent that is used to remove oils, fats, greases, waxes, resins, bitumen, rubber, and cellulose acetate. It is also used as an ingredient in adhesives, inks, or paint strippers. The most common uses for MC are paint stripping, metal cleaning, and furniture stripping. 

CH2C12 Dichloromethane (methylene chloride) Paint strippers 40... 

Paint stripper formulations containing DBE solvents have replaced many of the methylene chloride-based strippers. The DBE can be used alone or with cosolvents like N-methyl-2-pyrrolidone (NMP) and a hydrocarbon (Table ll.lO) [3]. Formulations A and B in the table are effective for many paints. A blend of 60 wt% DBE and 40 wt% NMP or a blend of 60 wt% DBE and 40 wt% ethyl-3-ethoxypropionate can be used in a hot dip operation. The preferred dibasic esters in these blends are DBE-2 and DBE-3 because of their low vapor pressures. 

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