Paint common solvents

Some solid materials are very intractable to analysis by standard methods and cannot be easily vaporized or dissolved in common solvents. Glass, bone, dried paint, and archaeological samples are common examples. These materials would now be examined by laser ablation, a technique that produces an aerosol of particulate matter. The laser can be used in its defocused mode for surface profiling or in its focused mode for depth profiling. Interestingly, lasers can be used to vaporize even thermally labile materials through use of the matrix-assisted laser desorption ionization (MALDI) method variant. 

Common solvent in the chemical and pharmaceutical industries used in the production of lubricating oils and as intermediary in the manufacture of chloroform and in the manufacture of plastics, paints, varnishes and cosmetics. 

The two most common solvents for carrying penta into the wood are a relatively high-boilmg No. 2 fuel oil and a very low-boiling liquified petroleum gas, butane. When fuel oil is used it remains in the wood and although the end product is brighter and cleaner than creosote-treated wood, it has a somewhat oily character and cannot readily be painted. When LP gas is used as the solvent, the butane is recovered and the penta is deposited in the wood as a dry crystalline material, hence the wood retains its color and is readily pain table. 

PROBLEM 1.11 A 1.000 mL sample of acetone, a common solvent used as a paint remover, was placed in a small bottle whose mass was known to be 38.0015 g. The following values were obtained when the acetone-filled bottle was weighed 38.7798 g, 38.7795 g, and 38.7801 g. How would you characterize the precision and accuracy of these measurements if the actual mass of the acetone was 0.7791 g ... 

Synonyms 2-propanone, dimethyl ketone Formula CH3COCH3 MW 58.08 CAS [67-64-1] used as a common solvent in many organic syntheses and in paint and varnish removers colorless liquid characteristic odor, sweetish taste boils at 56.5°C vapor pressure 180 torr at 20°C freezes at -94°C density 0.79 g/ML at 20°C readily mixes with water and organic solvent highly flammable. 

Other methods for forming blends such as by evaporation of a solvent or by polymerization of a monomer in the presence of a polymer involve at least three components in the preparation process. Mixing in a common solvent followed by its removal is a convenient way of making blends on a laboratory scale, but has obvious commercial disadvantages due to the cost and difficulty of solvent recovery as well as the potential environmental hazards associated with handling large volumes of often toxic chemicals. In specific applications, however, such as membrane formation or paints and coatings where thin films are required, the use of solvents is unavoidable. 

The PAn/DNNSA is highly soluble (it is not a dispersion) in nonpolar organic solvents such as xylene and toluene, common solvents used in many paints. It has a molecular weight (Mw) > 22,000 and an electrical conductivity of 10 5 S cm-1. Interestingly, treatment of a PAn/DNNSA film with methanol or acetone leads to a marked (five orders of magnitude) increase in conductivity, which is believed to arise from extraction of excess DNNSA dopant causing an increase in polymer crystallinity. 

Acetone is used in the manufacture of a large number of compounds, such as acetic acid, chloroform, mesityl oxide, and MIBK in the manufacmre of rayon, photographic films, and explosives as a common solvent in paint and varnish removers and for purifying paraffins. 

Products and Uses An oily liquid derived from the pine tree. It is in varnishes, insecticides, paint thinners, wax-based polishes, shoe polishes, furniture polishes, liniments (medicinal), antiseptics, and perfumery. A common solvent. 

Properties Amber-colored, heavy transparent liq. sol. in all common solvents dens. 1.05 Toxicology TLV (as Zr) 5 mg/m of air Precaution Combustible Uses Ceramics (enamels, glazes) lubricants paints and varnishes (anti-chalking agent, minimizer of moisture and solar radiation effects)... 

Paint removal is accomplished by either chemical or blast depainting. Dichloromethane is the most common solvent used for this application. Aerospace industry estimates that 15,000 to 30,000 different materials are used for manufacturing some of which are potentially toxic, volatile, flammable, and contain chlorofluorocarbons. Some of these substances may result in air emissions, waste-waters, and solid waste. 

The use of paints and varnishes containing high solvent concentrations is becoming less common, solvent-reduced products, waterborne coatings and solvent-free products are applied more often. 

Juta hyclca resin n. Brazihan resin occasionally used in certain types of varnishes. It is a very hard and pale-colored material, insoluble in most of the common solvents. Lan-genheim JH (2003) Plant resins chemistry, evolution ecology and ethnobotany. Timber Press, Portland, OR. Paint pigment, drying oils, polymers, resins, naval stores, cellulosics esters, and ink vehicles, vol 3. American Society for Testing and Material, Conshohocken, PA, 2001. 

Nowadays, the most commonly used solvents are mineral or white spirits. Aromatic hydrocarbon solvents, such as xylene and toluene, are used in certain specialized industrial paints. Other solvents include a wide variety of alcohols (isobutanol, i-butanol), esters (ethyl acetate, butyl or isobutylacetate) and ketones (acetone, methyl ethyl ketone). Often, a mixture of different solvents is used to ensure the desired outcome, e.g., in thinners (Mathias 1984 Valsecchi et al. 1992 Rose and Vance 1997 Leira 1997). In Scandinavia, there has been a tendency for more than a decade to reduce the use of the more toxic solvents, including benzene, n-hexane and the chlorinated solvents, particularly carbon tetrachloride, chloroform, dichloroethane and trichloroethylene (Leira 1997). 

Paints are used for cosmetic as well as protective reasons (in the form of coatings). Within this group, there are acrylic paints commonly used which contain PMMA in a solvent (which evaporates as the paint dries), which makes the paint surface, hard, tough and shiny. Since PMMA is hydrophobic, to make the acrylic paint waterbourne, poly(vinyl alcohol-co-vinyl acetate) copolymer is generally used, where PMMA can stay suspended in water, (known as PMMA latex and latex paints). 

In the case of water-based or latex emulsion type paints, there would be un-reacted (free to evaporate) monomers, glycols and glycol ethers, alcohols, amines, and possibly formaldehyde, free monomers and plasticisers, that will continue to be generated for a long time after the paint has dried. However, the VOC level in a water-based paint is generally much lower than other common solvent-based products due to slower evaporation of VOC producing constituents. 

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