Solvent cleaning rubbers

The main uses of petroleum naphtha fall into the general areas of (1) solvents (diluents) for paints, (2) dry-cleaning solvents, (3) solvents for cutback asphalts, (4) solvents in rubber industry, and (5) solvents for industrial extraction processes. Turpentine, the older and more conventional solvent for paints, has now been almost completely replaced by the cheaper and more abundant petroleum naphtha. 

Special oils are obtained after the motor fuels during distillation. These oils are used for lighter fuel, dry cleaning, solvents for cleaning, wax, polish, solvents for paint and solvents for rubber. 

These are used for preparing adhesives and for metal cleaning by removing grease, oils, dirt, etc. Trichloroethylene, toluene, xylene, ethyl acetate, methyl ethyl ketone and hexane are the most commonly used solvents in rubber lining manufacture and application. Sometimes a mixture of one or two of the above solvents is used for evaporation make up of the adhesive solutions. For closed tank linings trichloroethylene is the preferred solvents from the safety point of view. 

MAJOR USES Used in industry for recovery of tin in tin plating waste, formulation of gasoline additives, refrigerants and propellants, metal degreasing, production of semiconductors, cleaning of machinery and electrical equipment used as a solvent for rubber cement, oils, fats. 

OTHER COMMENTS used as solvents in rubber industry during manufacture of waterproof cloth, shoe adhesives, and rubber tires used in preparation of paint, varnish, and lacquer as solvents, diluents, orthinners utilized during dry cleaning operations use as an extractant. 

SD alcohol 35-A solvent, process rosin SD alcohol 1 SD alcohol 3-A SD alcohol 3-C SD alcohol 12-A solvent, process rubber latex SD alcohol 1 SD alcohol 3-A SD alcohol 3-C solvent, process vaccines SD alcohol 1 SD alcohol 2-B SD alcohol 3-A SD alcohol 3-C SD alcohol 12-A SD alcohol 13-A SD alcohol 23-A SD alcohol 30 SD alcohol 32 SD alcohol 35-A solvent, process vitamins SD alcohol 1 SD alcohol 2-B SD alcohol 3-A SD alcohol 3-C SD alcohol 12-A SD alcohol 13-A SD alcohol 23-A SD alcohol 30 SD alcohol 32 SD alcohol 35-A solvent, process yeast SD alcohol 1 SD alcohol 2-B SD alcohol 3-A SD alcohol 3-C SD alcohol 12-A SD alcohol 13-A SD alcohol 23-A SD alcohol 30 SD alcohol 32 SD alcohol 35-A solvent, processing cleaning oils Petroleum distillates... 

Thermoplastics like polymethyl methacrylate (PMMA) or polystyrene should be thoroughly cleaned with a non-solvent such as isopropanol to remove surface contaminants. Abrasion is sometimes necessary to remove all traces of mold release agents. Cyanoacrylates form very strong bonds with many thermoplastics because the monomer swells into the adherend, and when cured, forms an intimate mixture of the plastic and the polycyanoacrylate. Thermosets such as filled phenolics should be treated in the same way as thermoplastics. Rubbers usually require abrasion as well as solvent cleaning to prepare them for bonding. 

The procedure is as follows A small piece of the sample is extracted with solvents to remove additives. The piece is then placed in a pyrex tube and heated with the tube held horizontally in a Bnnsen flame. As the sample decomposes, a tan-colored liqnid will condense on the sides of the tube. This is the pyrolyzate. It can be removed from the tnbe with a clean rubber policeman, transferred to an IR window, and scanned as a capillary film. 

Uses Dewaxing agent solvent scour used with caustic for cleaning rubber print blankets and to remove metallic pigment dispersions leveling agent for overdyed Dacron stripper on many colors Rexosolve CR [Emkay ]... 

Glue Rubber and PVC cemenr Cleaning solvents Degreaser Spot remover Dry cleaning fluid Halothane... 

Contamination is a major problem in lipid analysis and the use of plastic containers and stoppers, rubber bungs or tubing, and any grease on stopcocks, etc., must be avoided. All solvents used should be of the purest grade and be peroxide-free and all glassware should be scrupulously clean. 

Carbon tetrachloride was at one time widely used in industry, and still is to a certain extent, although its use as a degreaser or common solvent has been banned in many jurisdictions. Until recently, however, it was commonly used as a degreaser and a solvent for oils, fats, lacquers, varnishes, rubber waxes, and resins. Two of its most common uses were in the dry cleaning industry and in portable fire extinguishers. 

The variety of applications emphasizes the versatility of naphtha. For example, naphtha is used in paint, printing ink, and polish manufacturing and in the rubber and adhesive industries, as well as in the preparation of edible oils, perfumes, glues, and fats. Further uses are found in the dry-cleaning, leather, and fur industries and in the pesticide field. The characteristics that determine the suitability of naphtha for a particular use are volatility, solvent properties (dissolving power), purity, and odor (generally the lack thereof). 

So-called peripheral neuropathies can result from excessive exposure to certain industrial solvents such as carbon disulfide (CS2, used in the rubber and rayon industries) and hexane (CgHn, once used in certain glues and cleaning fluids). Over-exposure to acrylamide, an important industrial chemical, and chronic alcohol abuse can also induce this effect. As the name implies, it involves attack of the chemical on and damage to axonal portions of neurons. Typical symptoms of peripheral neuropathies include weakness or numbness in the limbs, which are more or less reversible depending upon the specific agent and the intensity of exposure. 

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