Abstract: Disclosed is a process for removing polychlorinated biphenyls from electrical apparatus, particularly transformers, to achieve concentration levels of 50 ppm or less as required by the EPA. A dielectric fluid having a relatively low boiling point as compared to polychlorinated biphenyls and other contaminants and in which PCB's are soluble is selected. There is an external cooling loop through which the dielectric fluid is circulated maintaining the temperature and pressure of the transformer within its design limits. There is an external distillation loop where the liquid removed from the transformer is heated to boiling point of the selected dielectric fluid thereby vaporizing the dielectric fluid and leaving the polychlorinated biphenyls in liquid phase in the distillation vessel. The dielectric fluid vapor is then condensed and returned to solubilize remaining PCB's in the transformer.
Abstract: N-Pyrazinyl-haloacetamide having insecticidal, herbicidal, or fungicidal activity. The compound has the general formula: ##STR1## wherein R is hydrogen, hydrocarbyl, halogen, epoxy, hydroxy, alkoxy, mercapto, alkylthio, nitro, cyano or amino; R' is hydrogen or hydrocarbyl; X is halogen; m is an integer from 1 to 4; and n is 0, 1 or 2. The compound may also be a tautomer or acid addition salt of this formula.
Abstract: A retro Diels Alder assisted polymer grafting process in which a Diels Alder adduct is mixed with a polyolefin or polyvinyl polymer substrate and thermally decomposed to form an ethylenically unsaturated monomer which grafts onto the polymer substrate. The monomer conforms generally to the formula R.sub.1 R.sub.2 C.dbd.CHR.sub.3 in which R.sub.1 is hydrogen, methyl or ethyl, R.sub.2 is hydrogen, methyl, ethyl or vinyl and R.sub.3 is a hydroxyl, carboxyl, cyano, formyl, acetyl or propanoyl. The Diels Alder adduct substantially decomposes at a temperature of about 120.degree.-300.degree. C., but does not substantially decompose below about 120.degree. C. The polymer substrate is preferably high-density polyethylene, low density polyethylene, linear low density polyethylene, ethylene-propylene rubber, polypropylene, polystyrene or styrene-butadiene block copolymers. The grafting is induced by, for example, heat, catalyst and/or high shear conditions.
June 6, 1986
Date of Patent:
April 19, 1988
The Dow Chemical Company
Ricky L. Tabor, Paul L. Neill, Bradley L. Davis
Abstract: Aqueous dispersions useful in adhesive and coating applications, and a method of preparing the same. The dispersion contains (a) an ethylene interpolymer having an acid number of at least 117, a melt flow of at least 50, and comprising from 15 to 24 percent by weight of the interpolymer of interpolymerized ethylenically unsaturated carboxylic acid, such as acrylic or methacrylic acid, (b) from about 5 to about 2,000 parts by weight per 100 parts of the interpolymer of a rosin tackifier having an acid number of at least about 76 and being compatible and codispersible with the interpolymer, (c) water in an amount sufficient to provide a solids content of the dispersion of from about 10 to about 60 percent, and (d) water soluble alkali in an amount effective to neutralize from 20 to 130 percent of the acid groups in the interpolymer and the tackifier, to disperse at least 99 percent by weight of the interpolymer and the tackifier, and to provide a viscosity of the dispersion which is less than about 1,500 Pa-s.
Abstract: Halogenated interpolymers of ethylene and carbon monoxide. The halogenated interpolymer is prepared by (a) preparing a mixture of a liquid medium and a backbone polymer having interpolymerized therein ethylene and carbon monoxide, (b) contacting the backbone polymer in the mixture with halogen at conditions effective to react the halogen only with carbon atoms in the alpha position with respect to the carbonyl groups in the backbone polymer, and (c) recovering the halogenated polymer of step (b). The halogenated interpolymer is useful in molding films and articles therefrom and as a plasticizer in polyvinyl chloride resins. In a preferred embodiment, the backbone polymer has a carbon monoxide content of about 8-20 wt. percent and the halogenated interpolymer has a halide content of about 10-24 wt. percent.