Technology Such fuel tends to make a vehicle run more noisily and produce more smoke unless the engine is precisely and frequently tuned. Alcohol solutions of OSC derived from some varieties of coal haven't performed so well as when the OSC used is made from peat, Schulz admits, mainly because of their relatively high viscosity and poor lubricity. These shortcomings might be overcome, he suggests, by modifying the process parameters so that the molecular weight spectrum of the product would impart the desired viscosity to the solution. Lack of lubricity could be corrected by adding appropriate lubricants. "Alcohols," Schulz points out, "are an economically attractive alternate to petroleum-derived motor fuels. Their use in diesel engines is particularly attractive in view of the higher energy efficiencies [of these engines] compared to combustion in spark engines." But to function satisfactorily in a diesel engine, alcohols need an ignition promoter, usually an alkyl nitrate, which adds to their cost. OSC, with its alkyl components, functions as an ignition promoter as well as being a fuel in its own right. And its cost is about half that of methanol, Schulz observes. "Coal's excellent ignitability, a prerequisite for diesel fuels, resides in its highly reactive aliphatic components," he notes. Others, including Rudolf Diesel himself, have looked at powdered coal to run diesel engines. Some have tried a slurry of coal in water. "Presence of ash, however, a severe detriment to engine life, remains the obstacle to any practical use of coal as fuel for internal combustion engines," Schulz observes. "Solids handling also presents a major inconvenience. Liquefaction is the obvious solution to these problems. It requires dissection of large coal [molecular] structures into much smaller fragments to provide the basis for liquidity. This also allows removal of solid contaminants." Some argue that a development program centered on coal as a diesel fuel source might not be warranted, given the weak price and abundance of oil. But this might not always be so. Indeed, Helga 24
July 1, 1985 C&EN
Steeg, executive director of the International Energy Agency, cautions that industrial countries should not be lulled into a sense of false security by current abundant energy supplies. IEA foresees sustained economic growth in the last decade of the century and a decline in oil production in the industrialized world.
Additionally, OSC could have significance for countries that have sizable peat deposits. Schulz also suggests that Brazil, w h e r e sugarderived ethanol is being used to run automobiles, could convert its bagasse waste into OSC for blending with the alcohol and use as diesel fuel. •
Symposium celebrates Flory's 75th birthday During his five decades of scientific research, Paul J. Flory has played a central role in laying the foundations of modern polymer science. On the occasion of his 75th birthday, which he celebrated June 19, more than 100 of his colleagues gathered at Stanford University for an international symposium that paid tribute to Flory and his accom-
plishments. Entitled "Foundations and Challenges of Polymer Science," the symposium brought together a broad range of polymer scientists. Many of them began their careers as graduate students or postdoctoral fellows under Flory, and many others had collaborated with Flory at one time or another. Among the many distinguished participants were Nobel Laureates Herman F. Mark and Henry Taube. Flory, who received the Nobel Prize in Chemistry in 1974, is an emeritus professor of chemistry at Stanford, where he maintains an active research program. The symposium was sponsored by Stanford and IBM, with which Flory has long maintained a consulting relationship. The symposium was organized by James E. Mark, chemistry professor at the University of Cincinnati, and Leo Mandelkern, chemistry professor at Florida State University. The symposium's scientific preFlory with his wife, Emily (left), and holding first edition of his collected works (below), presented to him by FSU's Mandelkern
Flory (left) converses with French polymer chemist Henri Benoit sentations clearly demonstrated that Flory's ideas now permeate almost every aspect of polymer science. Indeed, those presentations, on subjects ranging from the thermodynamics of polymer solutions to rubberlike elasticity to liquid crystals, drew liberally on theories and equations that have Flory's name attached to them. "This meeting demonstrates the astounding scope of Paul Flory's work in polymer chemistry/' observed William R. Krigbaum, chemistry professor at Duke University, in his preface to a discussion of research on liquid crystals. Krigbaum pointed out that Flory's 1956 paper on the theory of polymeric liquid crystals anticipated by 10 years synthesis of such compounds. T h r o u g h o u t the m e e t i n g , researchers cited Flory's scientific intuition and his ability to translate intuition into theory. Ulrich W. Suter, an associate professor of chemical engineering at Massachusetts Institute of Technology, described efforts to model the bulk properties of glassy polypropylene. "Our calculations, which have consumed tens of thousands of dollars worth of computer time, conform almost perfectly with a prediction Paul Flory made 35 years ago on the basis of a back-of-the-envelope type of calculation," Suter says. At the conclusion of the sympo-
sium, Herman Mark—another giant in the history of polymer science, who celebrated his 90th birthday in May (C&EN, May 20, page 32)—paid tribute to Flory's ability to overcome the gap that often exists between theory and experiment. Flory's theories have proved prescient, Mark says, but he also has been a gifted experimentalist who worked to verify his theories. At a banquet held in conjunction with the symposium, Akihiro Abe, a former Flory collaborator who is a faculty member of the department of polymer engineering at Tokyo Institute of Technology, presented Flory with a scroll making him an honorary member of the Chemical Society of Japan. Also at the banquet, Leo Mandelkern gave Flory the first edition of the three-volume set of Flory's collected writings, which were published by Stanford University Press in honor of his 75th birthday. Rudy Baum, San Francisco
Baseball bats made of graphite composite New bats introduced this week by Worth Bat Co. threaten to send wood baseball bats the way of wood tennis rackets—yielding to stronger, lighter, more durable man-made materials. The Tullahoma, Tenn., firm has begun selling bats molded from a custom-formulated Xenoy DX 6302 resin—a graphite-reinforced polycarbonate / polybutylene terephthalate blend—developed by General Electric Plastics. Previous attempts to introduce plastic bats have been unsuccessful, a Worth spokesman notes. The problem is to find lightweight materials durable enough to withstand repeated 180-mph-plus impacts (a bat moving 90 mph meeting a ball pitched 90 mph or more). Indeed, even wood bats frequently crack. Aluminum bats combine light weight and durability and have become widely used during the past decade in nonprofessional baseball—Little League, high school, college, and other amateur leagues— and in softball. Worth makes wood
Worker removes from mold bat made of graphite-reinforced thermoplastic and aluminum bats, and is one of three approved makers of bats for major-league baseball. However, balls hit with aluminum bats produce an annoying pinging sound. Bats made of the new engineering thermoplastic, by contrast, yield a solid cracking sound like bats made of wood. The new bats will sell for about $90, comparable to top-of-the-line aluminum bats. Wood bats cost only $10 to $20, but the composite bats likely will last at least five to 10 times longer and produce better performance than wood, according to Worth. The composite bats are formed in a molding machine around a steel core pin. Their hollow shell is filled with cellular urethane foam in a manner that provides a center of gravity for the bat's "sweet spot"—the area that makes the ball travel farthest—and to dissipate impact vibrations. Moving the sweet spot and center of gravity toward the bat handle makes the bat feel lighter and enlarges the sweet spot. This lets a hitter generate more bat speed and maintain better bat control. The result could be better contact and placement of the ball—not more home runs, but more hits. Worth will focus its marketing on amateur baseball and softball. At least for the next few years, the firm expects the conservative professionals to stick with wood. • July 1, 1985 C&EN
25
