BRIEFS Summary of papers published in this month's research quarterly, 1@EC Product Research and Development COMPUTER APPLICATIONS I N MATERIALS EVALUATION PROGRAMS
Application of computer technology to Union Carbide Corp.'s rigid foam evaluation program has saved substantial time in data calculations, transcribing, and tabulation, and improved the accuracy of the data obtained. A system of computer programs accepts as input the original measurements obtained by laboratory assistants, and generates as output the calculated results in forms suitable for transmission to submitting laboratories, inclusion in evaluation reports, and information retrieval procedures. Application of a similar system to elastomer evaluation indicates that this approach may be generally applicable to all materials evaluation programs. Carlos J . Hilado, Union Carbide Cor)., South Charleston, W . V a . IKD.ENG.CHFX PROD.RES.DEVELOP. 5, 301-305 (1966)
DRYING AND OXIDATION RATES FOR LINOLEIC MODIFIED ALKYD RESINS
The hardening rates and volumetric rates of catalyzed oxygen absorption during film formation at 21" C. were examined as a function of molecular weight for a n alkyd resin prepared by a solvent process reaction from glycerol, phthalic anhydride, and linoleic acid in the molar ratio of 1 : 1 : 0.4. T h e rate of oxygen uptake up to 150 hours a t 22 O C. increased with increasing molecular weight. I t is hypothesized that a diffusion limitation was imposed on the termination step of the free radical oxidation process. This diffusional limitation is related to current gelation theory.
E. G. Bobalek, E. R. Moore, and J . R. Slidton; Case Institute
01Tech-
nology, Cleveland, Ohio.
IND.ENG.CHEM.PROD.RES.DEVELOP. 5 , 323-325 (1966) ANTIOXIDANT INHIBITION BY SUBSTITUTED PHENOLS. ANTIOXIDANT EFFICACY AS A FUNCTION OF STRUCTURE AND REACTIVITY
Induction periods conferred by a number of substituted phenols at 0.002M have bccn mcasured under standard conditions in cumene at 126.5' C. and in a-methylstyrene at 81.0' C. Antioxidant efficacies in both systems show good correlations with thc polarographic half-wave oxidation potentials of the phenols and also correlate well ivith the sums of electrophilic substituent constants, even for several trisubstituted phenols. T h e emergence of a well defined optimum reactivity in the cumene inhibition data is interpreted in terms of a dual competition of the chaintransfer inhibition reaction with both substrate propagation and direct antioxidant-oxygen reactions.
W'. G. Lloyd, R. G. Zimmerman: and A . J . Dietzler, T h e Daw Chemical Go., >Midland, M i c h . IND.
ENG.CHEM. PROD. R E S . DEVELOP. 5 , 326-330 (1966)
TELOMERIZATION OF ETHYLENE WITH TRIMETHYL BORATE CHARACTERIZATION OF PROPELLANT BINDER INGREDIENTS THROUGH GEL PERMEATION CHROMATOGRAPHY
Polyurethanes, the structures of which are controlled by varying the concentrations and types of diols and triols, are applicable as gel materials for separation of propellant binder ingredients through gel permeation chromatography. Preparation of the gels and columns is simple ; separations are efficient and reproducible. T h e general technique of G P C greatly facilitates the study of the relationship of chemical composition of propellant binder ingredients with the mechanical properties of binders and propellants prepared from the materials. Data on analytical and mechanical properties indicate that the functionalities of some of these materials vary greatly with molecular w-eight fractions. Further investigation of these and other propellant binder ingredients through this approach is recommended. Clarence Gustavson and E. A . Woychesin, Aerojet-General Cor)., Sacl-amento, Gal$. IND.EKG. CHEM.PROD.RES.DEVELOP. 5, 314-319 (1966) OXIDATION PRODUCTS I N AN OXYGEN-BLOWN KUWAIT ASPHALT
A Kuwait asphalt flux, which is ordinarily very difficult to harden by a n air-blowing process, was treated with oxygen to prepare a coating-grade asphalt. Oxidative changes were measured by increase in softening point and by infrared spectroscopy. The infrared spectra of the coating-grade asphalt to which model organic compounds were added were compared with the spectrum of the original asphalt. The principal oxygen-containing products formed during oxidation and photooxidation, as assigned by infrared analysis and several colorimetric methods, were acids, aldehydes, ketones, and peroxides, which confirmed previous findings with asphalts from other geographical sources. Paul G. Campbell and Janzes R. W r i g h f , nhtional Bureau of Standards, Washington, D. C. IND. END. CHEM. PROD.RES.DEVELOP. 5, 319-323 (1966) 80
INDUSTRIAL A N D ENGINEERING CHEMISTRY
A systematic study of the effects of reaction variables on the tclomerization of ethylene with trimethyl borate was carried out using di-tert-butyl peroxide as an initiator. Long-chain alcohols were recovered from the resulting long-chain alkyl borates by methanolysis. The yield of product per gram of initiator increased with increasing ethylene partial pressure, increasing temperature, or decreasing amount of initiator added. The molecular weight of thc product increased with increasing ethylene partial prcssurc and decreasing temperature. Hydrocarbons and ethers were also found in the product. A considerable amount of the alcohols recovered from the methanolysis was found to be secondary and the percentage of secondary alcohol 17aried inversely with the molecular weight of the product.
W. T . House, S. D . Sumerford, A . H . ,Veal, and W . J . Porter, Esso Research Laboratories, Humble Oil E Refining Co., Baton Roige, L a . IND.E N G .
CHEM.
PROD.R E S . DEVELOP. 5, 330-334 (19663
VAPOR PHASE ISOMERIZATION OF o-CARBORANE
An irriproved process for the conversion of o-carborane to its meta and para isomers involves heating carborane vapors, admixed with a n inert carrier gas, in a heated tube at atmospheric pressure. This accomplishes the isomerization rapidly in a continuous fashion, eliminating the need for the heavy pressure equipment required in previous methods. Optimum conversion of o- to mcarborane occurred at a tube temperature of 600" C., with a residence time of 0.30 to 0.48 minute and mass flows of 0.73 to 2.98 grams per minute; the meta isomer was recovered in yields u p to 98%. Mixtures of meta and para isomers were formed at 700°, the yield of para isomer being about Z2yo under optimum conditions. Stelvio Papetti, Clayton Obenland, and T. L. He&, Center, "few Haven, Conn.
Olin Research
IND.ENG.CHEM.PROD.RES.DEVELOP.5, 334-337 11966)
VAPOR PHASE BROMINATION
BRIEFS
OF 1,l-DIFLUOROETHANE
T h e direct thermal bromination of ethylidene fluoride using a n excess of bromine a t 600' to 650 C. has been used to produce a combined product of 1,2,2-tribromo-l,l-difluoroethane a n d 1,2,2,2tetrabromo-1 ,I-difluoroethane in good yields. T h e use of bromineethylidene fluoride mole ratios of 1.1 or less at 450' C. resulted in a conversion to 1-bromo-1,l-difluoroethane of 75%, but a t 575 to 600' C. gave conversions to vinylidene fluoride of 65 to 7570. T h e reaction probably proceeded by elimination of HBr, followed by bromination of the double bond. T h e reaction may be r u n or 1,2,2stepwise to produce either 1,2-dibromo-1,l-difluoroethane tribromo-1,l-difluoroethaneas the principal product.
R . A . Davis and M . R. Broadworth, Dow Chemical Go., Midland, Mich.
IND. ENG.CHEM.PROD.RES.DEVELOP. 5 , 337-339 (1966'1 HALOGENATED POLYEPOXIDE-AMINE COMPOSITIONS
T h e diglycidyl derivative of N-pentachlorophenylethylenediamine and the corresponding brominated compound were synthesized. When mixed with conventional epoxy resins to obtain practical halogen contents, good heat distortion temperatures and flame retardancy were obtained. A similar resin with a higher functionality, made by epoxylation of the octachlorobiphenylethylenediamine reaction product, cured with amine- or anhydride-type curing agents, gave excellent heat distortion temperatures and good fire-retardant characteristics without addition of conventional epoxies. Two types of new solid epoxy resins containing N-pentachlorophenylethylenediamine were compared with a commercial brominated epoxy resin. Amine-chlorinated aromatic compounds obtained by the reaction of ethylenediamine with octachlorodiphenyl as well as the reaction of diethylenetriamine with hexachlorobenzene and octachlorodiphenyl were tested as curing agents for nonhalogenated epoxy resins. Depending upon the structure of the curing agent, the castings had fair to good heat distortion temperatures and fire-retardant characteristics.
Bart J . Bremmer, The Dow Chemical Co., Midland, Mich. I N D .END.CHEM.PROD.RES.DEVELOP. 5 , 340-346 (1966)
ESTERIFICATION RATES OF LONG CHAIN HYDROCARBON DICARBOXYLIC ACIDS AND THE STERIC ENVIRONMENT I N THE VICINITY OF THE ACID GROUPS
A series of aliphatic carboxylic acids, acid-terminated polybutadienes, and acid-terminated hydrogenated polybutadienes was esterified, and their rates were determined. T h e esterification was done with excess 1-butanol with p-toluenesulfonic acid in refluxing benzene. T h e kinetics of the reaction was determined by the rate at which water was evolved and checked in some instances by titration of the acid with base. T h e results indicated that the acid-terminated polybutadienes and their saturated analogs have two types of acid groups which differ in reactivity. T h e difference in reactivity was shown to arise from the presence of some a-vinyl groups from 1,2-addition or allylic rearrangement of the final butadiene group. T h e evidence was based on comparison of the fast and slow rates for hydrogenated polybutadienes with the rates for model acids. T h e idea of steric hindrance is shown to be quantitatively consistent with the data of Smith for the effect of substituents on the acid-catalyzed esterification of aliphatic acids.
R. H. Quacchia and A . J . Dt Milo, Aerojet-General Corp., Sacramento, Ca1;f. XND ENG CHEM.PROD.RES.DEVELOP. 5,351-354 (1966)
XANTHATION OF STARCH IN LOW-CONCENTRATION PASTES
Xanthates of starch c a n be formed in good yield by mixing carbon disulfide with alkaline 10% starch paste when the amount of xanthation required does not exceed 0.12 mole per repeating unit. 'The rate of xanthation increases with temperature a n d with alkali and starch concentration. T h e method is readily adaptable to a continuous low-cost process.
E. B. Lancaster, L . T. Black, H. F. Conway, and E. L . Grzgin, Jr., Northern Regional Research Laboratory, U.S.D.A., Peoria, Ill.
HYDROXYMETHYL REPLACEMENT REACTIONS OF TETRAKIS(HYDROXYMETHYL)PHOSPHONIIJM CHLORIDE:
I N D .ENG.CHEM.PROD.RES.DEVELOP. 5 , 354-356 (1966)
I n rhe prescncc of approximately an equivalcnt amount of base. tctrakis~,hydroxymethyl,phosplionium chloride reacts with a n a,3-unsaturated nitrilt~,acid> amide, and a n epoxide by \%'a?of hydroxymethyl group replncctnent. .\crylonitrile gavc tris 2cyanorrhyl ,phosphine, acrylic acid gave 2-tris;hydroxymethyl phosphinopropionic arid brtaine, acrylamide gave a mcthylolamide resin, and ethylcnc oxide gave, presumably, tris(2-hydroxycthyl,hydroxymeth!.lphosphonium chloridc. Hydroxymethyl replacement is believed to proceed rhrough con\vrsion of hydroxymcthylphosphonium salt to tcrtiary phosphine, and reaction of thc tertiary phosphine with the active double bond or epoxide ring. T h e sequence rrpeats itself i n rases whrre basic sprcies are generated. leading to the rcplaccmcnt of more than one hydromethyl group.
HYDRATION OF SODIUM TRIPOLYPHOSPHATE BY WATER VAPOR
Kinetics and mechanism studies on hydration of Forms I and I 1
NasPsOio by water vapor show that hydration starts after the amount of water reversibly adsorbed on the surface exceeds a critical value. Critical humidities for hydration were determined from 26' to 100' C. T h e effects of bed depth and specific surface area on the hydration rate were measured. Since the critical humidity a t a given temperature for hydration of Form I is much lower than that for Form 11, this property can be utilized in determining the Form I content of sodium tripolyphosphate.
C. Y . Shen, R. A . Herrmann, Inorganic Chemicals Division, Monsanto Go.,
lf 'illiani J . licllo, Hockcr Chmicul Corp., .\.iapura Falls, .Y. Y .
St. Louis, Mo.
IND. ESG. C w x . PROD.RES.D E V L L O P5 ,. 346-349 f.1966j
IND.ENG.CHEM.PROD.RES.DEVELOP. 5,357-362 (1966)
PRODUCTION OF GLYOXYLIC ACID
Glyoxylic acid may be simply produced by treating a n aqueous solution of maleic acid a t 15' to 25' C. with a slight excess over the stoichiometric quantity of ozone required by the equation: 0 8
CADMIUM PIGMENTS.
STRUCTURE AND COMPOSITION
T h e reaction is essentially quantitative. T h e formic acid and most of the water are distilled off at reduced pressure at 50' C., leaving glyoxylic acid monohydrate (purity greater than 97 yo)behind. T h e product may be crystallized to give a solid which melts over the range 36' to 55" C.
X-ray diffraction studies o n three series of cadmium sulfide-based pigments are reported : ZnS-CdS yellows, CdSe-CdS reds, a n d HgS-CdS reds. Each series is a set of solid solutions with the basic hexagonal cadmium sulfide structure. T h e changes in unit cell dimensions with composition are shown. These pigments are widely used in plastics and in coatings. T h e cadmium yellow a n d sulfoselenide red series have been known for many years; the mercuric sulfide red series is relatively new.
Walliam T. Black and Gerhard A . Cook, Union Carbide Gorp., TonaWanda, ?V.Y .
W. G. Huckle and G. F. Swigert, Hercules Powder Co., Glens Falls, N . Y., and S.E. Wiberley, Rensselaer Polytechnic Institute, Troy, N . Y .
I N D .ENG.CHEWPROD.RES.DEVELOP. 5,350-351 (1966)
IND.ENG.CHEM.PROD.RES.DEVELOP. 5 , 362-366 (1966)
HOOCCH=CHCOOH
+
CHO-COOH
+
+ HCOOH + COz.
VOL.
58
NO. 1 2
DECEMBER 1 9 6 6
81
