Safer Stripping and Cleaning Chemicals for Coatings and Polymers

Safter Stripping and Cleaning Chemicals for Coatings & Polymers

Reference List, Minnesota Technical Assistance Program, University of Minnesota

Chemicals for Coatings and Polymers

Alternative stripping and cleaning chemicals for coatings and polymers are marketed as alternatives to chlorinated solventsCmethylene chloride in particular. In some cases, these solvents require more time or stronger, physical action for cleaning surfaces. All have lower rates of evaporation and drying than the chlorinated solvents they might replace. The cleaning claims on this list are made primarily by the manufacturer. Some claims are augmented by reports from the U.S. Environmental Protection Agency (EPA) and third parties.

Other alternative stripping methods include: abrasive blasting, water blasting, scraping, sanding, tumbling, burn-off and cold shock. Products and methods should be selected for use based on individual facility needs.

Safety Information

Information on health and environmental effects of some of the alternative chemicals is not as complete as information on traditional stripping chemicals. Available information indicates that the alternatives are safer, in most respects, than chlorinated solvents. Some of this is due to slow evaporation rates resulting in low worker exposure.

One measure of safety is the exposure limit. Estimates, based on eight-hour exposure, are made by various authorities: the Occupational Safety and Health Administration (OSHA); the American Congress of Governmental Industrial Hygienists (ACGIH); or a manufacturer. OSHA establishes the legally enforceable standard. However, the ACGIH standard is generally recognized as the prudent industrial standard in the absence of an OSHA limit or when new information suggests an established OSHA limit is too lenient, as in the case of methylene chloride.

The vapor hazard ratio¹ is another measure of safety. This is the likelihood that an exposure limit will be exceeded with normal use; it does not apply if the solvent will be sprayed or atomized. The vapor hazard ratio is estimated by dividing the vapor pressure of a product (the tendency of a solvent to get into the air) by the exposure limit (risk). The higher this number, the greater the chance the exposure limit will be exceeded due to solvent evaporation. But, this is a comparison of relative risks and there is no level on this scale where a chemical is determined unsafe.

The hazard rating for health, flammability and reactivity is assigned to pure chemicals by the National Fire Protection Association (NFPA). A similar rating can be assigned to products by their manufacturer using the National Paint and Coatings Association (NPCA) Hazardous Materials Information Systems (HMIS) criteria. Because the HMIS is more subjective, the following table gives HMIS ratings only in the absence of NFPA ratings.

MnTAP maintains this list of alternative stripping and cleaning chemicals for coatings and polymers solely as a service to Minnesota companies. This is not a complete list of available suppliers and products, and does not represent an endorsement by MnTAP. MnTAP, by providing this list, does not represent that the products do or do not ensure compliance with environmental and safety laws in any specific application.

1William Popendorf, AVapor Pressure and Solvent Vapor Hazards,@ American Industrial Hygiene Association Journal, Vol. 45, October 1984, p. 719.

Alternative Stripping and Cleaning Chemicals for Coatings and Polymers

Supplier	Product/ Residues Removed	Flash Point	Exposure Limit	Vapor Pressure (mmHg)^a	Vapor Hazard Ratio^b	Hazard Rating
ARCO Chemical Company Newtown Square, PA 800/321-7000 Fax: 610/353-0789	N-methyl-2-pyrrolidone (NMP) Removes: ABS, epoxies, inks, lacquers, polyamides, polycarbonates, polyesters, polyurethanes, polyvinyl chloride (PVC) and varnish. Propylene carbonate Removes: alkyd paint, epoxy resins and urethane resins.	200° F 226° F	100 parts per million (ppm) (International Specialty Products) not established	0.29 0.03	3.9 NA	2:2:0 1:1:0
Cook Composites and Polymers Kansas City, MO 816/391-6000 800/821-3590 Contact: Robert Uible Fax: 816/391-6236	Thermaclean products Aqueous cleaners. Removes: alkyds, grease, oil, polyesters and wax. Dibasic esters (DBE) and NMP solvent blends. Removes: epoxies, phenolics, polybutadienes, polyesters, urethanes and vinyl esters. Petroleum solvent blends. Removes: adhesives, EVA resins, grease, ink, oil, paint and urethanes.	>200° F >200° F 142° F	not established 1.5 ppm (DuPont) 50 ppm	not established 0.2 <1	NA 175 NA	1:1:0^c 2:1:0^c 2:2:0^c
DuPont Wilmington, DE 800/231-0998 Fax: 302/892-0938 Distributors: Ashland Chemical 800/582-0376 Chem Central 708/594-7000	Dibasic esters (DBE) Removes: acrylics, inks, paints, polyesters and polyurethanes.	212° F	1.5 ppm (DuPont)	0.2	175	1:1:0
Dynaloy, Inc. Indianapolis, IN 800/669-5709 Fax: 800/671-9583	Dynasolve, Family of 23 products made from combinations of petroleum solvents, glycol ethers and NMP. Removes: acrylic resins, cured silicone, epoxy and urethanes.	varies	varies with each 100 ppm typically	<2 varies	NA	NA
Gaylord Chemical Corp. Slidell, LA 504/649-5464 800/426-6620 Contact: Dr. George Kvakovszky Fax: 504/649-0068	Dimethyl sulfoxide (DMSO) Removes: epoxies, paint, photo resists and polyurethanes.	192° F	100 ppm (DuPont)	0.556	6.1	1:1:0
	Note: If placed in a reducing environment, like a wastewater stream, DMSO will create strong odors even at low concentrations. Odors can be neutralized by oxidizing releases with bleach, peroxide or UV light.
Inland Technology, Inc. Tacoma, WA 253/383-1177 800/552-3100 Fax: 253/593-8749	Formulated solvents: Citrex (least aggressive) Xcaliber Aerostrip (most aggressive) All remove: ABS, ink, paint, polyesters, urethanes and vinyl.	144° F 136° F 125° F	not established not established not established	< 2 < 2 < 1	NA NA NA	1:2:0 1:2:0 1:2:0
International Specialty Products (ISP) Charlotte, NC 800/438-1859 Fax: 704/554-0911	N-methyl-2-pyrrolidone (NMP) (see ARCO Chemicals)	220° F	100 ppm (ISP)	0.29	3.9	2:2:0
Oakite Berkeley Heights, NJ 800/526-4473 Fax: 908/464-5658	Eurostrip 7048 (versions for steel and other metals) Two part alkaline stripper removes: acrylics, epoxy, polyester, powder paint and urethanes	>200° F	not established	not established	NA	NA
Purac America, Inc. Lincolnshire, IL 800/423-0457 Fax: 847/634-1992	Ethyl lactate, Butyl lactate Methyl lactate All remove: epoxy, grease, ink, isocyanates, mold release, oil, paint, polyamide resin, rosin flux and urethanes.	129° F 131° F	1.5 ppm (Purac) not established	1.7 2.6	1490 NA	2:2:0^c 1:2:0^c
Qual Tech Enterprises, Inc. San Francisco, CA 415/467-7887 Fax: 415/467-7092	Replacetone, aqueous cleaner. Removes: epoxies, paint and polyesters. Water based.	>200° F	not established	22	NA	0:0:0^c
Shell Chemical Company Lisle, IL 800/367-7658 Contact: Tim Vipond Fax: 713/241-8170	Diacetone alcohol Removes: acrylic resin, epoxy resin and fiberglass reinforced plastic.	133° F	50 ppm (OSHA)	.95	26	2:2:0
Turco Products Delaware, OH 740/369-1860 800/848-0085 Fax: 740/369-2470	Turco 6776LO, aqueous solution containing 5% formic acid. Turco 6813, aqueous solution containing 2% ammonia. Both remove: alkyd paints, cured epoxy, enamel and polyurethane.	none none	5 ppm (formic acid/OSHA) 25 ppm (ammonia/ OSHA)	<2 <2	26 2.1	NA NA

Chlorinated Solvent for Comparison

Supplier	Product/ Residues Removed	Flash Point	Exposure Limit	Vapor Pressure (mmHg)^a	Vapor Hazard Ratio^b	Hazard Rating
Various	Methylene chloride (DiChloroMethane) Removes: most coatings and resins.	none	OSHA 25 ppm	380	20,000^d	2:1:0

Table Key

^{a Vapor pressure measured at around
20EC
^{b Vapor hazard ratio is calculated by
dividing the vapor pressure by 760 mmHg, multiplying by one million to estimate the
equilibrium vapor concentration in parts per million, and then dividing the exposure limit
in parts per million.
^{c Estimated by the manufacturer, based
on the HMIS criteria.
^{d Based on status as a suspected
carcinogen.}}}}

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