First ferromagnetic orga ic polymers prepared Two independent research groups in the Soviet Union and U.S. just published accounts of the discovery of the first organic polymers that spontaneously become magnetic at ambient temperatures. This property, known as ferromagnetism, results when the spins of unpaired electrons in a material spontaneously orient themselves in the same direction, creating a bulk magnetic effect. Ferromagnetism is the last entry on the list of electronic properties that once were thought to be restricted to inorganic materials but have now also been observed in organic materials. That list includes metallic conductors, semiconductors, and superconductors. Organic ferromagnets might one day replace metals or metallic compounds now used for their magnetic properties, such as chromium dioxide, which is used to coat magnetic recording tape. The Soviet researchers, led by A. A. Ovchinnikov of Moscow's Institute of Chemical Physics, prepared their ferromagnetic material by polymerizing a stable biradical monomer consisting of a cyclic nitroxyl group attached to either end of a diacetylene fragment [Nature, 326, 370 (1987)]. The Soviets apparently were not able to control the degree of polymerization or the size of the polydiacetylene chains thus formed. In a commentary in the same issue of Nature, Richard H. Friend of the University of Cambridge, U.K., points out that "only a small fraction (0.1%) of the monomer prepared by the Soviets is converted to ferromagnetic polymer, although this fraction can be magnetically separated from the residue/' The polydiacetylene polymer remains ferromagnetic up to about 150 °C, a limit that Friend calls "respectably high." Above that temperature, the electron spins lose their alignment, leading to a loss of magnetism. The Soviet work is significant, Friend says, because it shows that the electron spins of polymer-bound radicals can align along the length of the polymer chain. But, he adds, it is "far from ideal," because the yield of ferromagnetic material is
so low and the product is so poorly characterized. The U.S. results, just published in Synthetic Metals [19, 709 (1987)], suffer from similar drawbacks. They were first announced in December 1984 at a scientific meeting by physicist Jerry B. Torrance of IBM Almaden Research Center in San Jose, Calif., and his coworkers. They have observed ferromagnetic behavior in a polymeric material produced by the reaction of 1,3,5-triaminobenzene with iodine. "The chemistry going on in this reaction is a real mess," Torrance says, and his group has not been able to characterize its material. The yield of ferromagnetic polymer in the reaction also is very small (at most 2%), and the product is "not very reproducible," he notes. Nevertheless, the material—when it is obtained—remains ferromagnetic to high temperatures, until it decomposes near 400 °C. Both groups have established that their polymer's ferromagnetism is not due to any metallic impurities. Despite the lack of high-yield, well-characterized products in the Soviet and American work, scientists expect these results "will certainly stimulate further efforts to synthesize other organic ferromagnets." In related work during the past year or so, Du Pont chemist Joel S. Miller and his coworkers have been able to prepare crystalline, organometallic charge-transfer salts such as decamethylferrocenium tetracyanoethylenide, which show reproducible ferromagnetism. However, unlike the aforementioned polymers, this particular salt, for instance, is a ferromagnet only at temperatures below 4.8 K. •
BP to acquire rest of Standard Oil British Petroleum announced last week that it will make a tender offer to acquire all of the outstanding shares of Standard Oil Co. that it does not already own. The U.K. firm currently owns 55% of Ohio-based Standard Oil, which ranks 59th among U.S. chemical producers.
BP will offer $70 per share in cash for the remaining 45% of Standard Oil, making the deal worth more than $7 billion. Standard Oil's stock price the day before the announcement was $647/8 per share. Thus the offer, which BP will make no later than April 1, represents a p r e m i u m of about 8% for stockholders. To finance part of the deal, BP is seeking loans for $5 billion in the form of a revolving credit with a four-year term. The combined firm will emerge as a moderate force in the U.S. chemical industry. BP's chemical sales figures in the U.S. are not available, but its BP North America subsidiary produces a number of polymers and specialty chemicals. Standard Oil's chemical sales in 1986 were $1.1 billion, down 21% from 1985, but its operating earnings from chemicals increased 7.5% to $57 million (excluding an extraordinary charge of $14 million in 1985). •
Chemical firms ride stock market surge For the first three months of 1987, chemical company stock prices have performed just about as stunningly as the widely accepted stock market yardstick, the Dow Jones Industrial Average, which continued setting new records last week. C&EN's chemical stock index— based on the weighted market value of stocks of American Cyanamid, Dow Chemical, W. R. Grace, Hercules, Monsanto, Rohm & Haas, and Union Carbide—increased 20.6% for the three-month period ending March 20, reaching a level of 532 (1957 = 100). That's essentially the same as the 21% growth in the Dow Jones Industrial Average over the same p e r i o d , r e a c h i n g 2333 on March 20. The chemical stock index outperformed the New York Stock Exchange Composite Index, which rose 18.7% during the period, and Standard and Poor's 500, which was up 19.4%. Generally, however, the indexes of smaller stock activity outperformed the chemical stock index. The best performance was tallied March 30, 1987 C&EN
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News of the Week
Chemical stocks reflect heady growth in major industrials over past three months C&EN index,3 1957 = 100 550
Dow Jones Industrial Average 2400
525
500
C&EN
^A
475 gjr
425
.......i..... i i Dec Jan L_iQa - 1 9 8 fi6—I - L
i
i
....
i
i Feb
2200
March 30, 1987 C&EN
532
% change
20.6%
2333.52
21.0
New York Stock Exchange Composite
142.65
169,37
18,7
American Stock Exchange Index
265.46
337.80
27.3
2100
Over-the-counter Composite
352.24
439.64
24.8
2000
Over-the-Counter Industrials
351.80
462.79
31,5
Standard & Poor's 500
249.73
298.17
19.4
Standard & Poor's 400 Industrials
277.90
341.99
23.1
March
a C&EN weighted stock price index of American Cyanamid, Dow Chemical, W. R. Grace, Hercules, Monsanto, Rohm & Haas, and Union Carbide.
6
441
March 20, 1987
1928.8S
-1987-
by the Over-the-Counter Industrials, which rose 31.5%, and the American Stock Exchange Index, which gained 27.3%. The Over-the-Counter Composite increased 24.8% and Standard & Poor's 400 Industrials rose 23.1%. Growth in C&EN's chemical stock index, good as it has been in the first quarter, still lags that recorded in the most recent annual overview of chemical stock performance in July 1986. At that time, the chemical stock index had posted an annual 47.2% rise to 399 on July 18, compared with the Dow Jones Industrial Average, which rose 30.8% to 1778. According to Shearson Lehman Brothers vice president and chemical industry analyst Theodore Semegran, recent chemical stock performance has benefited from continued strong chemical business, with particular strength in plastics and organic chemicals. Polypropylene and polyvinyl chloride sales have been particularly strong, he says, resulting in good market performances by three new companies whose stocks were listed on the New York Stock Exchange over the past three months: Aristech (up 63.4% since being issued and closing at $29 per share on March 20), Himont (up 36.8% and closing at $41% per share), and Vista (up 89% and closing at $32V8 per share). Of the companies in the C&EN
C&EN Chemical Stock Index Dow Jones industrial Average
1900
i
Dec, 19, 1986
2300
Dow Jones
450
Chemical stock index keeps pace with most other indexes
chemical stock index, Dow has been the best performer over the past three months, rising 35.2% to $82V2 per share on March 20. Next is Union Carbide, gaining 28.8% to close at $29 per share, and American Cyanamid, rising 21% to $97% per share.
The four other companies making up the chemical index had below-average increases, with Grace up 19.1% to $62V4 per share, Rohm & Haas up 18.3% to $43% per share, Hercules up 13.1% to $60V2 per share, and Monsanto down 0.3% to $78V4 per share. •
FDA plans to speed up some new drug approvals After years of debate and controversy, the Food & Drug Administration is about to enter revolutionary new territory in speeding the approval of new drugs aimed at treatment of terminal diseases. The regulations, in effect, would combine the selling and testing of new clinical formulations for patients with life-threatening diseases such as acquired immune deficiency syndrome (AIDS) and cancer. FDA announced its new proposals, called the "IND Rewrite/' in the March 19 issue of the Federal Register. The proposals would place on "fast track" the Investigational New Drugs process, allowing physicians to prescribe promising but incompletely tested drugs for terminal diseases. INDs are those drugs for which companies seek FDA approval in order to begin clinical trials. In one sense, FDA scientists would work with industrial researchers as they develop and test the new drugs.
Drug companies haven't come to any consensus about the proposal yet and were meeting last week at the Pharmaceutical Manufacturers Association in Washington, D.C., to develop one. But a major consumer group has long since been up in arms. "These new regulations," says Sidney M. Wolfe, director of the Public Citizen Health Research Group in Washington, "represent a gross decrease in the conditions necessary to distribute these drugs. It is an open invitation for companies to sell drugs that don't have good evidence of safety and efficacy. There are enough charlatans exploiting AIDS patients as it is." Wolfe says FDA's approval for the sale of azidothymidine (AZT) on March 20 was the model that should be followed. "That was a closed clinical trial," he says. "It involved controlled studies, then distribution. FDA wants to go way beyond this and let these new drugs out loose and jeopardize already sick people." D
