The Chemical World This Week RESEARCH & TECHNOLOGY
FEBRUARY
10,
1964
CONCENTRATES
• Ionics, Inc., and Monsanto Chemical have set up an agreement involving patents (assigned to Ionics, Cambridge, Mass.) covering equipment and technology in electrochemical processing. Monsanto's Chemstrand division is constructing a multimillion dollar plant to make adiponitrile from acrylonitrile by an electrochemical process at Decatur, Ala. (Oct. 14, 1963, page 69). According to Dr. E. R. Gilliland, president of Ionics, the agreement provides for the sharing of Ionics' technology related to this and other chemical reactions and for payment of royalties to Ionics. ^ Techniques for measuring effectiveness of molecular sieves as adsorbents for oxygen and nitrogen at low partial pressures in hydrogen streams have been developed by Dr* R. M. Thorogood, Dr. C M . Wilson, and Dr. J. M. Geist of Air Products and Chemicals, Emmaus, Pa. Molecular sieves are used to remove trace impurities from hydrogen, thus minimizing explosion hazards in operating plants using process hydrogen. Two of the techniques involve chromatography and a third measures adsorption capacity by static saturation. The Air Products group has also developed a way to observe breakthrough curves at impurity concentrations as low as 0.5 p.p.m., Dr. Thorogood told last week's meeting of the American Institute of Chemical Engineers, in Memphis, Tenn. From a model based on adsorption-desorption-displacement mechanism for oxygen and nitrogen, the breakthrough time can be calculated under conditions of continuous multicomponent adsorption. ^ N e w epoxy resins and a hydrogenated bis* phenol-A w e r e among the highlights of the
18th Conference of the Society of the Plastics Industry's reinforced plastics division, held in Chicago, 111., last week. Two new high-strength epoxy resins are available from Union Carbide's plastics division. Called ERRA-0300 and ERLA-0400, the resins have very high tensile and compressive strength. For example, tensile modulus of ERRA-0300 at 160° C. is 672,000 p.s.i., and yield strength is 19,300 p.s.i. For ERLA-0400, the values are 709,000 p.s.i. and 17,500 p.s.i., respectively. Roth contain terminal cyclopentenyl oxide groups; conventional epoxy resins contain terminal diglycidyl ether groups. Currently, the two resins
are used to make deep submergence structures. However, they should find other applications where high operating pressures are required, Carbide says. Cost of the resins is $8.00 per pound. Hydrogenated bisphenol-A (HBPA) is being sold in commercial quantities by Monsanto Chemical. HRPA imparts improved chemical resistance to polyester resins, a one-year test by Monsanto shows. After a year in boiling 10% sodium hydroxide, for instance, the heat distortion temperature of the HRPA-based polyester changed only a little from its original value of 143° C , and kept 65% of its original flexural strength, Monsanto says. HBPA is used to make chemical-resistant reinforced plastics for coatings or for constructing industrial equipment. The compound also gives good chemical and stain resistance to coatings, particularly automobile and appliance base coats and appliance top coats. ^ Crystals of a new optically pumped laser material, neodymium-doped yttrium oxide,
have been prepared at Korad Corp., Santa Monica, Calif. Although the material has so far produced only pulse operation at liquid nitrogen temperatures, workers at the Union Carbide subsidiary believe that larger crystals will achieve continuous wave operation at room temperature. The only other crystal known to do this is neodymium-doped calcium* tungstate. Yttrium oxide is a better host material for trivalent rare earth additives, Korad says, and is harder and more durable than calcium tungstate. ^ A 215,000-curie cesium-137 source for food sterilization has been shipped to Brookhaven National Laboratory from Oak Ridge National Laboratory. It consists of 48 cesium chloride units and nine cesium glass units. The cesium-137 ( a waste product from fission in nuclear reactors) originated at the Atomic Energy Commission's Hanford, Wash., plant. Cesium chloride units were made by pressing dry powder into small rectangular blocks. Cesium glass was made by placing a dry mixture of cesium carbonate, silicon dioxide, and other materials in a graphite mold and melting in a furnace under nitrogen pressure. Cesium-137 is a strong gamma emitter with halfIife of 30 years. FEB. 10, 1964 C&EN
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