TECHNOLOGY - C&EN Global Enterprise (ACS Publications)

TECHNOLOGY ... Chem. Eng. News , 1954, 32 (23), pp 2278–2282 ... Could new pigments be developed to provide superior colors and greater opacity?...
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TECHNOLOGY THE COVER

Chemistry's Impact on Points X N THE COATINGS FIELD, the

scientist

-*· has not always maintained the key position he holds today. Thirty or more years ago, the manufacture of paint and varnish was art, pure and simple, and it was performed mostly by practical men ungraced by university degrees. In the main, plant operations were carried on by crude rule-of-thumb methods, used for centuries. The chemical transformations that actually took place inside of reaction kettles or after the final product was applied were matters of academic interest only, about which little was known. Gradually, this situation changed as paint, oil, and resin chemists began asking fundamental questions about the factors that afiFect protective coatings. How could oils be made to dry more rapidly? What could be done to improve the durability or chemical· resistance of paints? Could new pigments be developed to provide superior colors and greater opacity? By finding the answers to these and scores of other questions, chemists have dramatically transformed the paint industry from art to science. Prior to World War I, the protective coatings industry employed only a relatively few raw materials, almost all of them of natural origin: linseed oil, tung oil, turpentine, Congo resin, kauri resin. The only wThite pigments were white lead and zinc oxide. Colors were limited in range and seldom were altogether satisfactory. Problems were intensified as industry began calling for protective finishes that could stand up under extraordinary conditions of temperature, humidity, or direct exposure to chemicals. At the same time, industrial finishes were required to dry swiftly to meet steppedup production schedules. Among the most impressive early developments—and one that did much to awaken the paint industry to the importance of research—was the discovery of radically improved automotive finishes. In 1923, an automobile required seven coats of paint that took 10 days to dry. With the replacement of natural oils and resins by synthetic materials, all that was changed. Today, a car can be finished with two or three coats that dry in three hours or less, and the resulting finish is vastly more durable than anything ever known before. The past 30 years in the paint field has been a record of chemistry's impact on what has become a billion dollar in2278

dustry. Amor* g the most significant developments has been the creation of an ever-widening range of improved synthetic resins (see table). These products have macle possible not only faster drying schedules b u t also far more effective coatings ia specific applications. Pain* Research. Today, chemists have sufficient knowledge of paint fundamentals so tKat resin molecules can be tailor-made to meet exacting performance requirements. To the consumer, this knowledge has brought a host of benefits. For example, housewives can count on the outstanding whiteness, ha-rdness, and durability of alkyd-amino iresia combinations in finishes for refrigerators, washing machines, and other home equipment. Chemical lalboratories have brought forth finishes based on phenolic and epoxy resins that give high resistance to chemical atta_ck and salt-water corroDevelop men-t of Synthetic Resins for Protective Coatings 1924 ModifLed phenolic resins—for cooking with linseed and tung oils to produce ciuick-drying varnishes and enamels 1927 Alkyd resins—to formulate quick-drying interior and exterior finishes 1928 Pure phenolic oil-soluble resins —for cooking with tung oil to produce quick-Aying, chemically resistant varnishes and paints 1929 Urea-formaldehyde resins—to enhance the baking properties of alkyl industrial enamels 1930 Chlorinated rubber resins—for formulating quick-drying finishes 1933 Vinyl copolymers—for plastic sheeting and protective coatings 1935 Ethyl cellulose and cellulose acetolbutyrate—for fast air-drying coatings with improved light and heat stability 1939 Melaminc-formaldehyde resins —to provide fast cure and hardness in baking-type enamels 1944 Silicone resins—for heat-resistant coatings 1947 Polystyrene emulsions — for paper, clotli, leather, and concrete coatings having high resistance to acids., alkalies, and moisture and providing goocM exterior durability 1948 StyreiaatcA oils and alkyds—to formulate atlkyd-type enamels with a one-hour diry and which; on exposure, have excellent gloss retention and durability 1952 Polyvinyl acetate and acrylic copolymers—for latex-type paints having quick dry, excellent adhesion, and showing promise as an exterior latex paint CHEMICAL

sion. Extreme toughness combined with good chemical resistance is obtained from the polyvinyl chloride polymers. Silicone resins, permitting new standards of heat resistance, have at the same time revolutionized coatings for electrical insulation. An outgrowth of the emulsion polymerization piocess for synthetic rubber has been the production of latexes for water-base paints using styrene-butadiene, vinylacetate, and acrylic polymers. Another major contribution of chemistry has been the odorless paints based on chemically treated oils and resins and specially refined petroleum solvents. PaVaC Award. Among the chemists who have watched at close range the rapid strides made in recent decades in the coatings field have been last month's winners of the 1954 PaVaC Award. The New York Paint and Varnish Production Club presented the award to Cosmo A. Aloia, technical director and assistant general manager of the Sigmund Ullman and Eagle divisions of Sun Chemical; Carl L. Engelhardt, technical director of Brooklyn Paint & Varnish; and Louis J. Venuto, research director of Binney & Smith. Closely concerned with paints has been Carl L. Engelhardt of Brooklyn Paint and Varnish. Back in 1931, Engelhardt joined the company as a laboratory assistant. Working during the day and studying chemistry and chemical engineering at night, he received his degree from Pratt Institute in 1934. Over the years, he has advanced from production manager to chief chemist and now to membership on the company's board of directors. During World War II, Engelhardt devoted much effort to the development of moisture- and fungus-resistant coatings for the armed forces in the tropics. He also developed superior protective coatings for plywood which were of key importance in the production of aircraft during the wartime aluminum shortage. Active in the N e w York Paint and Varnish Production Club since 1937, Engelhardt has served on its technical subcommittees concerned with the measurement of permeability, the application of uniform films, and the determination of the dielectric strength of paint, varnish, and lacquer films. In addition, he has helped to establish the comparative merits of infrared and conventional oven baking and to develop methods of evaluating a variety of deep-tone flat wall paints. For some years, he has taken an active part in educational programs in the high schools, in an effort to interest young people in entering the protective coatings industry. Having at various AND

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For Example:

Nopco3" B O N D I N G and S I Z I N G AGENTS make things that should stay put, stay put Perhaps nothing exemplifies things that should "stay put" better than asphalt. Thousands of miles of roadway depend on its durability. Roadbeds rapidly deteriorate when the asphalt fails to bond properly to the aggregate. However, incorporation of a Nopco bonding aid in the asphalt instantly develops a tenacious permanent bond between cut-back asphalt and aggregate even if the stone is wet. Thus roads can be laid in rainy or inclement weather. In the production of asphalt shingles and tile this same Nopco aid gives better bond between asphalt and fillers, increases strength and gives a smoother surface. In a very different field, that of textiles, Nopco chemical agents are again found helping to

make things "stay put". For example, both natural and synthetic fibers must be sized before weaving, so that they are capable of withstanding the friction encountered on looms. Application of specially developed Nopco warp sizes, for natural and synthetic yarns, assures firm, yet flexible, coating over each individual thread to protect it from abrasion. Perhaps you are looking for a high-performance bonding aid, or sizing agent, that will better an item you produce. If so, profit by consulting with us. Or, if you require some other processing chemical, let us have your specifications. W e l l gladly make recommendations and work closely with you—putting our wealth of experience, modern facilities, and nationwide distribution set-up at your service. * Reg. U. S. Pat. Off.

Outstanding N O P C O Processing Chemicals include: EMULSIFIERS PLASTlCIZERS

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LUBRICANTS SI7.

DISPERSING AGENTS

DETERGENTS METALLIC SOAPS

JLjfVOLVtD

THRUVA

Branches:

DEFQAMERS

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WITH NOPCO BONDING AIC 24 hour immersion test shows virtually no stripping of RC-2 cutback Asphalt from wetted Massachusetts Rhyolite.

OPCO CHEMICAL COMPANY (Dept. CE) Harrison, N.J.

SURFACE TENSION REDUCING AGENTS

VOLUME

WITHOUT BONDING AID 24 hour immersion test illustrates almost complete stripping of RC-2 cutback A s p h a l t from wetted Massachusetts Rhyolite.

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Boston · Chicago

· Cedar town, Ga, · Richmond,

Calif.

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TECHNOLOGY. times served as treasurer, secretary, and vice president of NYPVPC, Engelhardt was president in 1947. Also active in NYPVPC has been Louis J. Venuto of Bimiey & Smith. Working on many of its subcommittees, h e has investigated the factors involved in pigment wetting, the properties of linseed oil, and the development of superior camouflaging agents. Today, h e is a leading member of NYPVPC's over-all advisory committee on technical projects. After receiving a B.S. in chemistry from the University of Pennsylvania in' 1923, Venuto joined Lee Rubber & Tire, where h e helped to develop a pigmented natural rubber latex paint for use on rubber tires. After joining Binney & Smith in 1924, he aided in setting up the world's first industrial laboratory for the exclusive study of carbon black. Since then, much of his work has centered around new physical forms and applications of carbon black. Venuto is coinventor of the bead or nondusting form of carbon black, which has vastly simplified the handling of this material in the paint, printing ink, and rubber industries. In 1927, he introduced the first carbon black surface treated with a dispersing agent for use in paints. In addition, Venuto has developed a variety of test methods for carbon black, such as the diphenyl guanidine adsorption test for total surface activity. Venuto, "widely in demand as a speaker before scientific societies, is the author of "Carbon Black for Protective and Decorative Coatings," which has been published not only in the U. S. but also in England, Germany, and Italy. Chief professional interest of the third 1954 PaVaC Award winner, Cosmo A. Aloia, is printing inks. After graduation from Pratt Institute in 1930 as a chemical engineer, Aloia joined the Sigmund Ullman division of what was then the General Printing Ink Corp. Aloia, in fact, was the first graduate chemist on the payroll. Transferred to the new research laboratories of the parent company in 1932, he was one of only three persons on the entire technical staff. In time, the research personnel numbered over 70. Aloia rejoined Sigmund Ullman in 1936, becoming chief chemist. Before long, his research and development group had become the nerve center of all plant activities, ranging from the control of incoming raw materials to the development of markedly improved new products. In 1949, Aloia was appointed assistant general manager, a post that today places him in close contact with sales. Holder of several patents on print2280

ing inks and vehicles, Aloia is a member of the ASTM subcommittee on printing inks and is also a member of the technical committee of the Packaging Institute. Aloia has been active in the N e w York Paint and Varnish Production Club since 1935. He was

president of the group in 1950. Says Aloia: "Thirty years ago, printing ink industry was in much the same position as the paint field. In the decades since, our industry has had the same growing pains and, as a science, the same kind of emergence."

Captain Mary Rukavina, U. S. Army nurse takes temperature of Sergeant Thomas L. Early, with the five to seven second, electric thermometer. Developer, Colonel Perkins, is an ardent "ham" radio operator and while reading a science magazine stumbled on an article on thermistors. Procuring several thermistors, he thought of making a thermometer. Together with J. E. Colby, Percy Jones Hospital, they had a working model in 30 days

March of the Thermometers Electric thermometers bypass Civil W a r mercury column instruments. Units are time saving compact g a d gets; remote control mechanisms TJLECTRIC, clinical, thermometers are -^ now competing with the mjercury column type. The new thermometers are said to give much faster and more accurate readings than their predecessors, the mercury column thermometers. Heart of the electric units are thermistors, small thermally sensitive resistors. For accurate temperature reading in five to seven seconds, a thermometer has been developed by George T. Perkins, director of the dental division of the Army Medical Service Graduate School, Walter Reed Army Medical Center, Washington, D. C. The instrument is being manufactured by the Burlington Instrument Co., Burlington, Iowa. The thermometer, known as Swiften, has a probe with a thermistor attached at the tip. The probe is less than five inches long, easily detachable for sterilization, and will obtain oral, rectal, or skin temperatures. A mercury cell battery powers the instrument and is connected to the sensing unit or probe by a transmission cord. Battery is unaffected by humidity and is contained in a plastic case CHEMICAL

which also houses a recording meterThe recording device resembles a typical photographic light meter and is operated by a finger button switch» Device is light in weight and compact enough to fit easily in the palm of the hand. Unit is designed to provide 7 5 0 hours of operation. Primary advantage of the new device is the number of man hours saved in the taking of temperatures. Although designed for on-the-moment, spot checking of temperatures, remote usage is also possible. According to Colonel Perkins, it would be possible for a nurse to remain at her ward desk and take a patient's temperature i n another part of the ward. Field trials for the instrument are tentatively scheduled to begin Aug. 1, and if successful, the thermometer may b e presented for standardization as an item of issue in the medical services of the Army, N"avy, and Air Force. For applications requiring remote readings and continuous temperature recordings, Yellow Springs Instrument has also designed an electric clinical thermometer. Operating mechanism of this instrument is very much akin t o AND

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Another new development

using

B.F.Goodrich Chemical «·—«**

B. F. Goodrich Chemical Company does not manufacture these plastic dip tubes. We supply the Geon resin only»

New ΌφκΛδ MoUotlôuit Covuutott IGID plastic pipe made from .Geon polyvinyl chloride helps cut down internal rust and corrosion in hot water heater tanks. The pipe, or "dip tube", was developed in the search for an answer to an o l d problem—electrolytic action between different metals used in hot water heaters which can cause corrosion through the steel tank itself. Because the dip tube is plastic, it d o e s n o t p r o m o t e this "battery action" inside the tank.

R

Geon resin was chosen for the dip tube after exhaustive tests of various plastics under all operating conditions. Perhaps a Geon material can help you reduce or eliminate corrosion where tubing, piping, ducts or tank linings are used. And, Geon materials have many m o r e uses where resistance to many acids, chemicals and water is important. We'll help you select the one best suited to your needs. For information,

p l e a s e w r i t e D e p t . G A - 5 , B· F. Goodrich Chemical Company, Rose Buiiding,Clevelandl5, Ohio.Cable address: Goodchemco. In Canada: Kitchener, Ontario.

GEON RESINS · GOOD-RITE PLASTICIZERS . . . the ideal team to make products easier, better and more saleable GEON polyvinyl materials V O L U M E

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HYCAR American rubber »

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GOOD-RITE chemicals and plasticizers

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H A R M O N colors 2281

TECHNOLOGY Yellow Springs Instruments TeleThermometers. A single channel unit is shown on the left and a six channel unit on the right. The sixchannel model may be supplied with internal or dermal probes or any combination of the two types. Each probe is connected to the measuring circuit alternately by the switch on the front panel, thus allowing comparative readings for up to six different locations the Swiften instrument. Called the Tele-Thermometer, basic constituents of instrument are also probe with thermistor, transmission cord, and battery. Battery, in this case, consists of a size D flashlight battery which suffices for over 2000 hours of continuous operation. The Tele-Thermometer has been used in the Fels Research Institute, Antioch College, for measurement of rectal and esophageal temperatures in hypothermic animals. At present two types of Tele-Thermometers are available; a single channel unit and a six channel unit. Either model may be equipped with flat (dermal) probe configuration or with rounded tip probes for rectal or esophageal measurements of temperature. Multichannel Tele-Thermometer has has six leads, including five for skin temperature determinations and one for internal body temperature. Consequently, a continuous check can be made of temperature changes over six different parts of the body. Alternatively, six different subjects can be telemetered at once. Tele-Thermometer is recommended for use in peripheral vascular work, physical therapy, monitoring effects of nerve blocks, sympathectomies, vasoconstrictors, and vasodilators.

coated insert. Then, the two sections are joined and welded with an oxyacetylene weld. Heat of the welding operation fuses the glass coating of the insert to the glass lining of the pipe.

W. A. Barrows, company president, points out that the pipe can now be used in sea water lines, as tubes for air preheaters i n power plants, as heat exchanger tubes, and in processes where catalysts are contaminated by metal contact and where protective coatings are required.

• Rugged industrial flooring m a t e rial, a rubber-based plastic made by U. S. Rubber, can take heavy wear, and is unaffected by chemicals, oil, and grease. Called Gam-En-Wood, flooring is Enrup (U. S. Rubber's trade name) and is bonded to solid or laminated hardwoods. It is being manufactured in either strip or block form by Gamble Brothers, Louisville, Ky. • Electric hygrometer of high sensitivity and extremely rapid response has been designed and constructed by National Bureau of Standards. With the hygrometer, a 6 3 % change in indication takes place in less than 1 / 2 second at room temperature and in about 10 seconds at —20° C. Unit depends on the physical adsorption of water vapor on a film surface. Hygrometer consists of a thin film of a salt, such as potassium dihydrogen phosphate, evaporated under vacuum on a specially treated strip of glass. An electronic circuit measures the resistance of the film. • Leak-detection method for atomic energy applications has been developed by Babcock & Wilcox. Company says method enables users to detect a leak so small that it would take a year to form a single drop. In the method, vessel being tested is filled with helium. Through use of a mass spectrometer leak detector, amount of helium that escapes into the surrounding atmosphere is measured. In this way, it is possible to detect the presence of one part of helium in 200,000 parts of air.

T w o Venuses in Sporty G a r b Ratio Mfg/s sport car body of advanced design is constructed of American Cyanamid's Laminae polyester resin reinforced with glass fibers. Known as the Ratio Venus, body is molded in one piece for easy mounting on a standard Ford Chassis of 1949 through 1951 models. Molded-in metal lugs are provided for bracket mounting to the chassis. Car shown is powered with a 1949 engine but engine compartment space is available for General Motors, Chrysler or Lincoln V-type engines

Borrows Develops Joining M e t h o d For Porcelain Enamel Lined Pipe A joining method for porcelain enamel lined pipe has been developed by Barrows Porcelain Enamel. The problem was to find a method of joining standard 21 foot lengths of pipe coated inside and out with porcelain enamel without impairing effectiveness of the coating. The new method uses a porcelain enamel coated insert of light gage metal. Pipe is field cut to give a fairly square end. Cut end of each section is fitted with a porcelain enamel 2282

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