BRIEFS of articles appearing in this month's quarterly - ACS Publications

BRIEFS of articles appearing in this month's quarterly. Ind. Eng. Chem. , 1966, 58 (9), pp 109–113. DOI: 10.1021/ie50681a013. Publication Date: Sept...
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BRIEFS Summary of papers published in this month's research quarterly, I&EC Product Research and Development

SELECTIVE PROPERTIES OF HIGH FLUX CELLULOSE ACETATE MEMBRANES TOWARD IONS IN NATURAL WATERS

The desalination properties of recently developed semipermeable membranes have been studied in reverse osmosis systems. Membranes were prepared from cellulose acetate-acetone-formamide solutions cured at three temperatures. Good salt rejection properties and high flux values were observed. Membranes reject divalent ions to a greater extent than monovalent ions, with no apparent regard to sign of charged ion. Greatest preferential ion selectivity occurs in complex multicomponent salt solutions; easily rejected ions are rejected to an even greater extent and easily passed ions pass more readily through the membrane. Greatest differential ion rejection occurs between 40 and 80 gallons per sq. foot per day; C a f Z ,Mg+2,and S04-2 are rejected 10 to 30% better than the average of all ions in solution. Synthetic solutions of sea water and Roswell brackish water were studied. I n both natural waters ~ Ca+2 > Mg+2> HCOa- > the order of ion rejection is S O A -> N a + > K + > C1- > Br-, with a membrane cured at 65' C. The selectivity of the membrane, as well as over-all desalination, is related to curing temperature. Membrane properties observed suggest the use of cellulose acetate membranes for reducing the concentration of scale-forming ions from natural saline waters; reverse osmosis would act as a first stage pretreatment of feed water for distilling plants, permitting distillation of concentrated saline waters a t higher temperatures and concentration factors than with untreated water.

D . L. Erickson, Julius Glater, and J . W. McCutchan, University of California, Los Angeles, Calif. IND.ENC.CHEM.PROD.RES.DEVELOP. 5, 205-211 (1966)

months. After exposure, the stiffness o each portion of film was measured by the cantilever beam method. Wavelengths below 300 mp had a large stiffening effect; those from 380 to 290 mp had a small effect. The technique is unique in that it permits the study of changes of physical properties attributable to the incremental effect of ultraviolet light. It could be broadly applied to studying the aging of rubber and plastic films.

W. C. Warner and E. E. Gruber, General Tire & Rubber Co., Akron, Ohio

IND.END.CHEM.PROD.RES. DEVELOP. 5 , 219-221 (1966)

STRUCTURAL EFFECTS OF ARYLSTEARIC ACIDS AS COMBINATION OXIDATION AND RUST INHIBITORS

Effect of variation in molecular configuration of hydroxyarylstearic acids on effectiveness as combination oxidation-rust inhibitors in bis(2-ethylhexyl) sebacate was studied. Alkyl groups ortho and para to the hydroxyl of 9(or 10)-hydroxyarylstearic acids enhanced the oxidation protection but decreased the rust protection somewhat. A second hydroxyl on the aryl ring-e.g., still better 9(or lo)-( 2,3-dihydroxyphenyl)stearic acid-yielded oxidation protection, while 9,12-bis(4-hydroxypheny1)stearic acid was the best antioxidant, with only a slight compromise in rust protection, of those studied. Alkaline earth soaps of the compounds were also effective combination inhibitors. The additives described are generally good antioxidants up to 175' C., effectiveness decreasing with increasing temperature, and provide adequate protection against rust.

Jonathan L. Snead, Joseph Messina, and Henry Gisser, Pitman-Dunn Research Laboratories, Frankford Arsenal, Philadelphia, Pa.

IND.END.CHEM.PROD.RES.DEVELOP. 5,222-225 (1966) LIFETIME OF CELLULOSE ACETATE REVERSE OSMOSIS MEMBRANES

A series of experiments was conducted to investigate the influence of feed water p H on the long-term performance of cellulose acetate reverse osmosis membranes. The decline in salt rejection observed for these membranes after extended exposure to feed solutions is attributed to hydrolysis of the cellulose acetate, and is found to be strongly pH-dependent. The rate of change of the membrane parameters can be correlated with the previous measurements of hydrolysis rates of cellulose acetate, and the dependence of membrane parameters on the acetyl content of the ester.

K . D . Vos, A . P. Hatcher, and U. Merten, General Dynamics Corp., San Diego, Calif. IND.ENG.CHEM.PROD.RES.DEVELOP. 5,211-218 (1966)

LIGHT AGING OF A POLYBLEND FILM UNDER INTERFERENCE FILTERS

A light-aging study was undertaken to find a suitable means to evaluate the stabilization of a mixture of poly(viny1 chloride) resin and a copolymer of 1,3-butadiene with 2-methyl-1-butene-3-one. Five interference filters provided a narrow window between 330 and 410 mp. A portion of film was mounted under each and exposed under a heliostat to Florida sun for approximately 2

ANTIOXIDANT REACTIONS OF lO-HYDROXY-l0,9-BOROXAROPHENANTHRE"

lO-Hydroxy-10,9-boroxarophenanthrene(BOP) is a highly effective inhibitor of the autoxidation of white oil at 150" C. I t showed no significant reactivity toward peroxy radicals at 60" C. At higher temperatures the antioxidation appears to proceed by the destruction of hydroperoxides. The rate of disappearance of BOP during the autoxidation of white oil was much faster than predicted from the response of inhibition period to concentration. This difference is attributed to the presence of a secondary antioxidant which is formed from BOP. Oxidation of the carbon-boron bond of BOP consumes 1 mole of hydroperoxide to give a cyclic borate which can further decompose hydroperoxides catalytically. The 10-hydroxy-10,9-boroxarophenanthreneserves as a reservoir, releasing on demand a highly reactive peroxide decomposer, thus providing an unusually high degree of antioxidation.

R. F. Bridger, A . L . Williams, and L. J . McCabe, Mobil Oil Corp., Princeton, N . J.

IND.END.CHEM.PROD.RES.DEVELOP. 5, 226-230 (1966) (Continued on page 1 11) VOL. 5 8

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STEAM CURE OF SILOXANE-COATED GLASS CONTAINERS. NEW APPROACH TO SURFACE PROTECTION AGAINST HYDROLYTIC CORROSION

A coating material was developed which protects annealed glass containers against physical damage and hydrolytic corrosion, and helps preserve strength through their normal life. Such modified glass surfaces display lubricity required for safe transfer through conveyor lines and pasteurizers and maintain the adhesive characteristics pertaining to the use of conventional glues throughout all handling operations. The new composition, synthesized by a free radical-induced polymerization reaction, contains recurring pairs of carboxylic acid groups which alternate with siloxy, secondary hydroxylic, and stearyl functions. These groups were selected from parent compounds known to protect the glass surface by chemical interaction (siloxanes) and lubrication (stearates) and which display outstanding adhesive properties [poly(vinyl alcohol)]. The acidity of the coating material produces a favorable medium for the interaction of its doxy functional groups with those located in the glass surface. Glass containers treated with this coating material are subsequently submitted to superheated steam, resulting in an increased number of interfacial bonds. A modified glass-resin surface with increased strength retention is obtained.

Paul Lagally and State College, Pa.

Priscilla Argyle, Linden Laboratories, Inc.,

IND.ENG.CHEM.PROD.RES.DEVELOP. 5,230-236 (1966)

PREPARATION OF THORIA AND MIXED-OXIDE MICROSPHERES

A process was developed for preparing thoria or thoria-urania spheres of 50- to 1000-micron diameter, high strength, and nearly theoretical density. Colloidal oxide sols were dispersed in an organic liquid and converted to gel spheres by extraction of water. To fluidize the sol drops and to avoid coalescence, clustering, and deposition on the wall, the use of surfactants in the solvent and of special vessel configurations was necessary. The gel spheres were separated from the solvent, dried, and calcined to 1150' C. Microspheres were prepared using 2-ethyl-I-hexanol as the drying solvent in a continuous column system including solvent recovery. Demonstrated capacities of the system were 5 kg. of 240-micron thoria spheres in one day or 700 grams per hour for short periods.

Paul A . Haas and S. D . Clinton, Oak Ridge National Laboratory, Oak Ridge, Tenn.

IND. ENC.CHEM.PROD.RES.DEVELOP. 5,236-244 (1966)

SURFACE EFFECTS IN THE PARTIAL OXIDATION OF PROPANE

Propane was partially oxidized with oxygen in both flow and batch glass reactors. The product composition and the time required for the batch runs varied as the reactors were used (or were aged), indicating that surface changes were occurring as the reactors were used. A rather gradual change was probably caused by a change in the glass itself. More rapid changes between and during the runs were apparently caused by carbonaceous films deposited during the reaction. Acetaldehyde deactivates a reactor, by apparently attacking these films. Product analyses were made using a four-column gas chromatographic unit.

L. F. Albright and E. M . Winter, Puniue University, Lafayette, Ind. IND.ENG.CHEM.PROD.RES.DEVELOP. 5, 244-249 (1966)

DETECTION OF UNREACTED ALUMINA TRIHYDRATE IN SILICAALUMINA CATALYST

By performing differential thermal and thermogravimetric analyses on fresh silica-alumina catalyst samples, it was possible to detect and estimate the amount of aluminum which had not reacted with silanol groups during the preparation of silica-alumina catalyst. In the catalyst tested about 10% of the aluminum atoms had not reacted with silicon to form the AI-0-Si group, which is the active component in the catalyst.

Geoffrey R . Say and Howard F. Rase, The University of Texas, Austin, Tex.

IND.ENG.CHEM.PROD.RES.DEVELOP. 5, 250-252 (1966) CHLOROALKYL PHOSPHlNlC ACIDS. PREPARATION AND REACTION WITH COTTON

Two new compounds, bis( 1-hydroxy-2-chloroisopropyl)phosphinic and bis( 1-hydroxy-2,2 '-dichloroisopropy1)phosphinic acids, were prepared by the reaction of hypophosphorous acid with chloro-2propanone and 1,3-dichlor0-2-propanone, respectively. Bis(chloromethy1)-phosphinicacid was also prepared by the reaction of bis(hydroxymethy1)-phosphinic acid with thionyl chloride, a method not previously reported. All three acids were applied to cotton from aqueous solutions containing an excess of sodium hydroxide or sodium carbonate as a catalyst, and cured at elevated temperatures. Fabric samples treated with all three compounds were insoluble in cupriethylenediamine dihydroxide and had improved wet wrinkle recovery, indications that the cellulose was crosslinked. Analysis of the fabric showed the presence of one exchangeable hydrogen ion for each phosphorus atom, evidence of the presence of phosphinic acid groups in the fabric. Apparently, the cellulose hydroxyl groups react with the chlorine atoms of the phosphinic acids in the presence of a base to crosslink the cellulose by ether linkages. There was no significant improvement in dry wrinkle recovery over that of untreated cotton. Moisture regain values were considerably higher than those of untreated cotton. Fabric strength losses were not excessive, considering the degree of crosslinking.

Leon H. Chance, Ethel K. Leonard, and George L . Drake, Jr., Southern Regional Research Laboratory, New Orleans, La.

IND.ENO.CHEM.PROD.RES.DEVELOP. 5,252-257 (1966) PRODUCTION OF THE LEVOPIMARIC ACID-FORMALDEHYDE ADDUCT AND HYDROXYMETHYLATED MATERIALS FROM RESIN ACIDS AND ROSIN

Processes adaptable to large scale production of the levopimaric acid-formaldehyde adduct from pine gum or from purified levopimaric acid are described. This material was further converted to 6-hydroxymethylabietic acid and hydrogenated over palladiumcarbon catalyst to a thermally stable hydrogenated hydroxy acid and over copper-chromite catalyst to 6-hydroxymethyltetrahydroabietinol. A hydroxymethyltetrahydroabietinol was prepared by copper-chromite reduction of oxonated rosin. The thermal reaction of abietic acid and rosin with formaldehyde gave mixtures of hydroxymethylated acids which were not separated but showed an average of 0.7 to 0.9 equivalent of hydroxyl per equivalent of resin acids. Partial hydrogenation of these materials stabilized the methylol content considerably over the nonhydrogenated material. Pimaric acid did not react with paraformaldehyde under the conditions used.

B. A . Parkin, Jr., H. B. Summers, R. L . Settine, and G. W. Hedrick, Naval Stores Laboratory, Olustee, Fla. IND.

ENG.CHEM. PROD. RES.DEVELOP. 5 , 257-262 (1966)

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SYNTHESIS OF HIGH VISCOSITY POLYOLS

A number of high viscosity polyols for potential use as lubricants for automotive central hydraulic system fluids were synthesized. T o achieve the desired viscosity range of 1000 to 4000 cs. at 100 e F., small amounts of diepoxides (butadiene oxide, 3-vinylcyclohexene dioxide, or resorcinol diglycidyl ether) were copolymerized with ethylene and propylene oxides during the synthesis of the polyols. Sodium oxide or potassium hydroxide may be used as catalyst, but the former requires a higher reaction temperature.

H. F. Lederle and J . E. Mastroianni, 01% Mathieson Chemical Gorp., New Haven, Conn.

IND.ENG.CHEM.PROD.RES. DEVELOP.5, 262-265 (1966)

FUNCTIONAL FLUIDS FROM CHLOROMETHYLATED DIPHENYL OXIDE

The preparation and preliminary evaluation of a number of aromatic-aliphatic ethers and aromatic-fluoroaliphatic ethers are described. Many products have wide liquid ranges with pour points as low as -65’ F. Viscosities range from 10.73 to 212.1 cs. at 100’ F. and from 2.85 to 13.8 cs. at 210°F., with ASTM slopas ranging from 0.63 to 0.94. Spontaneous ignition temperatures as high as 1025 O F. were observed. Suitably purified, the aromaticfluoroaliphatic ethers pass the hydrolytic stability test of specification MIL-H-19457B.

Henry Lederle, Ehrenfried Kober, and Gerhard Ottmann, Olin Mathieson Chemical Gorp., New Haven, Conn.

IND.ENG.CHEM.PROD.RES.DEVELOP.5, 265-268 (1966)

PREPARATION OF DIMETHYLMORPHOLINE BY REACTION OF DIPROPYLENE GLYCOL WITH AMMONIA

Dimethylmorpholine is prepared by the catalytic reaction of commercial dipropylene glycol with ammonia. Conversions of above 65% and yields of about 80% are attained by passing the vaporized glycol with ammonia and hydrogen over a bed of 60% nickel-on-kieselguhr catalyst. The product produced from commercial dipropylene glycol is a mixture of 2,5- and 3,5-dimethylmorpholines. Typically, the process is carried out by feeding a vaporized mixture of dipropylene glycol, water, hydrogen, and ammonia in a mole ratio of 1 :1 :3: 5 over the catalyst at 190 O C. and at a feed rate corresponding to 0.1 gram per gram of catalyst per hour. I n addition to dimethylmorpholine, the condensed efRuent from the reaction contains unsaturated cyclics which are converted to dimethylmorpholine by catalytic hydrogenation.

W. K . Langdon, W . W. Levis, Jr., and Ernest Jaul, Wyandotte Chemicals Corg., Wyandotte, Mich.

IND.END.CHEM.PROD.RES.DEVELOP.5, 268-272 (1966)

STARCH-DERIVED GLYCOL GLYCOSIDE POLYETHERS FOR URETHANE FOAMS. PROCESS SCALE-UP, PERFORMANCE IN FOAMS, AND COST ESTIMATES

In a pilot-plant study of the preparation of polyethers from glycol glycosides obtained directly from starch, scale-up from a laboratory procedure was readily achieved to 1000 pounds of polyether per batch. Extensive evaluation of the polyethers for use in rigid urethane foams was made by appropriate formulation with PAP1 or Nacconate 4040 isocyanates, with and without flame retardants, and with machine foaming. “Plant gate cost” of the polyethers was estimated to be around 15 cents per pound, based on current raw material and plant operating costs. Fixed capital investment was estimated at $375,000 for construction of a unit designed to produce 10,000,000 pounds of polyether per year. The low production cost of the new polyethers is expected to make them competitive with polyethers currently in use.

R. H . Leitheiser, C. N . Impola, and R. J.Reid, Archer Daniels Midland Co., Minneapolis, Minn., and F. H. Otey, Northern Regional Research Laboratory, Peoria, Ill. IND. ENG.CHEM.PROD.RES.DEVELOP. 5, 276-282 (1966) NOVEL PROCESS FOR PREPARATION OF INORGANIC FOAMS

Alumina and silica refractories possessing densities of less than 30 pounds per cubic foot have been produced using aromatic unsaturated polyester resins as the foamable polymer system. The polyester system developed can support inorganic fillers over a temperature range of 25 to 1950 O C. (77 O to 3500’ F,). Although foamed shapes undergo considerable shrinkage in that temperature range, this method produces low density refractories without internal cracks and without substantial change in the original foamed shapes. The fact that aromatic unsaturated polyester foams perform better than other foamable polymer systems can be explained through the kinetics of the thermal degradation of these polyesters.

Marc0 Wismer and J . F. BOSSO, Pittsburgh Plate Glass Go., Springdale, Pa.

IND.ENC.CHEM.PROD.RES.DEVELOP. 5, 282-287 (1966) IDENTIFICATION OF BRAKE LINING CONSTITUENTS BY PYROLYSIS GAS CHROMATOGRAPHY

Compositional differences between commercial automotive brake lining materials are distinguishable by means of pyrolysis of the sample followed by chromatographic separation and infrared identification of the degradation products. A standard gas chromatograph equipped with a pyrolysis introduction system provides chromatograms characteristic of the binder resins. The method easily distinguishes major differences in binder materials and, with close control of operating parameters, provides fair repeatability for most peaks. A relatively small sample is required and valuable information can be obtained in less than 2 hours per sample.

Gerald E. Fisher and James C. Neerman, Ford Motor Go., Dearborn, Mich. ALKALINE HYDROLYSIS OF SODIUM TRIMETAPHOSPHATE IN CONCENTRATED SOLUTIONS AND ITS ROLE IN BUILT DETERGENTS

IND.ENG.CHEM.PROD.RES.DEVELOP.5, 288-292 (1966)

The conversion rate and mechanism of sodium trimetaphosphate to sodium tripolyphosphate in concentrated alkaline solutions were determined. For most detergent slurries, the conversion rate is fast enough so that sodium trimetaphosphate can be advantageously used as a source of sodium tripolyphosphate. Sodium trimetaphosphate seems to offer a new technology in processing built detergents.

A chemical milling technique is evaluated as an integral operation for processing microelectronic circuit panels. Process parameters affecting this operation are identified. Two methods were developed to predict the time for milling cylindrical holes through reinforced plastic by a study of kinetic and physicochemical changes.

C. Y. Shen, Mowanto Go., St. Louis, Afo.

R. M . Shah0 and W. E. Skillman 111, Autonetics, Anaheim, Gal$.

IND.END.CHEM.PROD. RES. DEVELOP.5,272-276 (1966)

INDENG.CHEM.PROD.RES.DEVELOP. 5, 293-300 (1966)

CHEMICAL MILLING OF CIRCUIT PANELS

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