Document reX9aK6zKXr3y7g6b2519QL7E

L-26 L-26, the normal lead salt of 2-ethylhexoic acid, is a pale straw colored, mild odored, viscous liquid containing approximately 41 per cent lead. Insoluble in waters and alcohols, it is readily miscible with a wide variety of common organic solvents and plasticizers, forming stable solutions. Because of its unique combinations of properties, L-26 riiay be used to advan tage as-a-driot' fo> paints and vawBEgfas, as a hardening or vulcanizing agent for various types of synthetic resins, as a component of waterproofing compounds and lubricants, and for a variety of other uses. Table of Properties Composition .... ....... ................. ....................Lead 2-Ethyl Hexoate Formula_________________ _______ Pb[CH3(CH2)3CH(C2H5)COO]2 Molecular Weight -......... ...... !......................493.38 Specific Gravity________________ ________ 1.52 at 25 C Weight per Gallon inPounds..................12.6 Viscosity (Gardner-Holdt) .......................Z8 to Z10 (25C) Color (Gardner 1933 std.) ....... ............. _1-- Lead Content (% Pb) -------------- --.........40 to 41.5% Solubility.... .......... ........................... .......-..... Soluble in the petroleum hydrocarbons, ethyl ether, dibutyl phthalate, carbon tetrachloride, benzene, xylene, ethyl acetate, methyl ethyl ketone and many other organic solvents. Insoluble in methanol, ethanol, ethylene glycol and water. Uses Its unique property of being liquid at room temperature, its high lead content and its wide range of solubility in many readily available organic solvents indicate that L-26 has many potential uses including the following: iPoint Dpier--L>26 is ar^excell^pt defer fonpainj*. It compares v/ry favorably with/me bjsit of thelead dners in^pe^d of d/ying^nd in tj>C colq^stahiIfty-^n the dried paint film./LiquhPariers/^onidinin^L-2^nav/f'ex<fellepir'packag^stability ^emaimng free from dedim^jzf indefinitely, r NLI 114302 ^Because o its higljjfead contpnfL-26 is.oomparable in cost with the beat driers aijdin addi ' 1 "he distja^t advant^g6 of ljght colopafid unobjectionable odor. r--lining togethpf'with apfroprmfquandties oLfhanganesturfid successfully pass >He Federal Specification On Curdling in rawjitfseed Hardener for Silicone Paint Films--It has been found that silicone resins can be made to dry to a glossy adherent film on sheet metal when a soluble organic lead salt is added to a mineral spirits solution of the silicone resin to the extent of about 0.4% Pb content based on the resin, and the coated surface is exposed to infra red radiation for 15 minutes at 25C.* The finish is improved by continued exposure to infra red heat at 250C for an additional eighteen hours. A simulated automobile finish of 75% resin, 17% solvent naphtha, 0.4% lead equivalent sol uble organic lead salt and 8% of maroon toner gave a finish which could not be marred by the thumbnail, a gloss of 82 at 60 and a finish which was as close an approach to a ceramic finish as any paint film thus far achieved. Our own Research Laboratory tests with L-26 confirm the findings of the National Paint Varnish & Lacquer Association. L-26, which does not vaporize at 300 C and which decomposes before boiling, gives excellent color and color reten tion in baked finishes. The same formulations dried tack-free in 16 hours without application of heat. Both baked and air-dried films exhibited excellent adhesion, flexibility, hard ness, good dielectric properties and impermeability to moisture. The process of drying the film is not an oxidation reaction and since gelling of the silicone is progressive after 3 to 6 days at room temperature L-26 must be added to the resin directly before use. Hardener for Silicone Insulating Varnishes--With silicone resins used for the coating of electrical equipment such as motor coils, etc., the time of curing can be cut down, without impairing the physical and electrical characteristics of the coatings, by using a combination treatment consisting of the incorporation of 0.8% Pb content as L-26 in the resin, a short treatment with infra-red radiation followed by another short treatment with ultra-violet light. This treatment gets rid of solvent after which the ultra-violet treatment catalyzes the polymerization and hardening of the resin to a tough adherent film. The reaction in the case of both the silicone paint and insulating varnish is catalytic and the drying is not an oxidation as it takes place even in the absence of air. As explained under the heading of "Hardener or Silicone Paint Films," L-26 must be added to the insulating resin just prior to application. Asphalt Base Solvent Removable Rust Preventative Coatings--L-26 is an excellent ingredient to improve the impermeability to water,-flexibility and film adhesion to metal parts of asphalt-base temporary coatings. Additions of L-26 * National Paint Varnish and Lacquer Association--Scientific Section Circ. 70S. NLI 114303 equivalent to 2.50% of the weight of the finished paint give excellent protective coatings. Protective coatings of this type can be easily removed with mineral spirits or > other common solvents such as benzene. In this manner metal surfaces which can not be painted with permanent coatings may be protected until such time as the metal equipment goes into service. Vulcanizing Agent for Liquid Organic Polysulphide Polymers--L-26 serves as a curing agent for the impregnation of leather with liquid organic poly sulphide resins. The leather is treated with a 10% solution of L-26 in benzene. The solvent is driven off and the treated leather is saturated with the liquid organic poly sulphide resin and heat is applied to vulcanize the resin. The resulting product combines the oil resistant, solvent resistant, and gas impervious characteristics of the polysulphide vulcanizate with the strength and other desirable properties of leather. This application suggests the possibility of modification to include the impreg nation of paper, fiber glass, asbestos, cotton and other fibrous material with the liquid organic polysulphide polymers. Potential Uses--All of the uses noted have been dependent upon the fact that the L-26 is soluble in common solvents and is stable at relatively high temperatures. This would suggest its potential use as a reinforcing agent for lubricating oil and greases, as a hardening agent for alkyd resins, etc. A recently suggested use of L-26 in connection with silicone paint films is in the pretreatment of white metal and bronze bearings. It is predicted that bearings coated with the silicone paints resist corrosion in storage and make it possible to use machines, such as automobiles, the hearings of which have been thus coated, with out the necessity for the customary "breaking in" period at low speeds. NATIONAL LEAD COMPANY General Offices 111 Broadway, New York 6, N. Y. 116 Oak St., Buffalo 3; 900 West 18th St., Chicago 8; 659 Freeman Ave, Cincinnati 3; 1213 West Third St., Cleveland 13; 722 Chestnut St, St Louis 1; 2240-24th St, San Francisco 10; National Lead Co. of Mass., 800 Albany St, Boston 6; John T. Lewis & Bros. Co, Widener Bldg., Philadelphia 7; National Lead Co. of Pa., 1376 River Ave, Pittsburgh 30. i.. F-67-47 NLI 114304