IC&ENJ feature
synthetic ' fibers:
urgency in
EDMUND M. BURAS, JR., Harris Research Laboratories, Inc., Washington, D.C.
If researchh is is the foundation of production
technology,
then the Soviet Union clearly intends that its synthetic fiber industry shall rest on a firm footing
82
C & E N AUG. 7, 1961
As the Soviet Union's current Seven Year Plan nears its midpoint, it is interesting to take stock of accomplishments realized so far. We have seen (C&EN, July 31, page 126) that the goal is to increase artificial and synthetic fiber production about four times, to 640,000 tons in 1965. We have also noted the intent, within this schedule, to increase synthetic fiber production alone at least 12-fold. This reflects greater regard for consumer desires of the ordinary Soviet citizen. It also bespeaks a vast Soviet synthetic fiber industry based largely on accomplishments of home grown research efforts. Fiber research in the Soviet Union wasn't born of the new Seven Year Plan. But neither was it a very healthy baby before the government's economic planners decided to forcefeed it on a nourishing diet of rubles and priorities. For such solicitude the Soviet people can perhaps thank Nikita Khrushchev himself who, in his finest desk-thumping manner, made it clear in 1958 that the situation must change. If the Soviet Union wanted a large and productive synthetic fiber industry in a hurry, then almost certainly a goodly proportion of its plant and know-how had to come from foreign sources. But if, in the long run, it also wanted an industry backed by solid substance in the form of basic science, then it had to provide the people and facilities to build up that science. So it was that a sizable expansion of the Soviet Union's network of scientific institutions was planned for 1960. Much of that expansion has taken place. One way of gaging its
progress is to note the results it has produced in the form of scientific reports in the technical press. Before 1952, reports on synthetic fiber research and development in the technical press were practically nonexistent. Since that year, some 400 papers have been published, and the majority of these appeared in the past two years. Thus, the most salient feature of synthetic fiber research in the U.S.S.R is rapidity of growth. The current of research and development progress seems far greater than just three or four years ago; and if this be true, the volume of reports in the literature must also continue to grow at a high rate in coming years. But rapidity is only one feature. There are others. Soviet synthetic fiber research is skillful. It is creative. Since 1951 it has been responsible for or contributed greatly to bringing not fewer than 10 synthetic fibers to full or pilot scale production. Moreover, three of these are purely Soviet products right from the start. Certainly, achievements such as these must earn the highest respect for the research groups responsible for them. Many areas of polymer research bear an important relationship to fiber and textile technology. And, in the Soviet Union, each of these areas is directed by men whose competence in research has long since been established. The Standard Is
Competence
Many polymer scientists in the U.S. are already acquainted with the work of N. V. Mikhailov, director of the All-Union Scientific Research Institute
This is the second of Uoo articles resulting from, a survey of the Soviet scientific literature and popular press conducted by the author on a continuing basis. Last week he discussed the Soviet Union's synthetic fiber industry, and this week he deals with its synthetic fiber research
Soviet research
for Synthetic Fibers (VNIIV). Z. A. Rogovin, working at the Moscow Textile Institute, is notable for taking diverse exploratory paths and coming up with brand-new ideas. His work on iluorocarbon fibers, in association with Z. A. Zazulina, has spawned a material that apparently has no American counterpart. And then there's V. V. Korshak, who is with the Institute of Elementorganic Compounds in Moscow. Again and again his name appears in the Soviet polymer and fiber literature as author or coauthor of scientific reports. These and many others have shown that, if new routes to better fibers are to be found, they are capable of finding them. Currently, the rate at which these Soviet scientists publish significant technical articles is about equal to the rate at which similar articles appear in the U.S. Their literature is scanty on dyeing, finishing, and utilization. But, other than that, they have about the same interests as we do. Senior authorship of more than half the papers is divided among fewer than 20 persons. But this abundance on the part of the few stems at least partly from different authorship standards than exist in the U.S. Heads of institutions and academicians are listed on so many papers that it seems almost impossible that they could personally have been active in all the projects involved. Nearly a quarter of the papers appear as numbers of a series, and possibly some authors are listed to preserve continuity within the series. If we were to list references on synthetic fiber research, about 400 authors in all would have to be cited. The number of scientists and tech-
S0VF0T0
FUTURE EXPERTS. Students at Tashkent Textile Institute learn to evaluate fabric quality. The instructor is Dr. M. Khodzhinova. Soviet science places high value on the technician's supporting role AUG.
7, 1 9 6 1 C & E N
83
. . . more people, planning
expanded
are all preludes
expanded
production,
effort,
to more
better
better research,
fibers
her research papers comes from these four organizations, and they appear regularly in at least five journals. Two of the journals, Yy.sokomoiekiilyitnnjf Soediiicniya (High Molecular Weight Compounds) and Khimichcskic Yolokmi (Chemical Fibers), were established especially for articles in these
fields. Expansion on Broad Scale
nieians working in synthetic fiber research and related polymer fields probably totals 1500 or more. About 100 scientists working at the project-leader le\cl are distributed among four major research institutions devoted to textile research. These are the All-Union
Scientific Research Institute for Synthetic Fibers (YXflYh the Moscow Textile Institute, and the institute for Elementorganie Compounds, all located in Moscow, and the S, M. Kirov Textile Institute at Leningrad, The greater portion of published JR-
S0VF0T0
PILOT PLANT. Worker draws Lavsan resin from autoclave in pilot unit at the All-Union Scientific Research institute for Synthetic Fibers. Lavsan, Capron, Anid, and Mitron are the four fibers selected bv Soviet olanners for increased oroductton 84
C&EN
AUG.
?,
1961
The Soviet Union's expansion of research effort takes varied forms. Besides more personnel, it includes new facilities, broader objectives, and closer cooperation between the different groups. For example, at the Institute of Elementorganic Compounds, a new division is concerned mainly with applications of "elementorganic" compounds—those with silicon, oxygen, phosphorus, etc., as well as carbon in the principal chain—in making new types of fiber-forming polymers. institutes of organic chemistry at Kazan. Novosibirsk, and Irkutsk are slated to function as research centers on many problems in their regions. The chemistry of fiber-forming polymers is within their scope. Some of the older institutes of the Soviet Academy of Sciences, such as that in the Uzbek Republic, are now publishing on fibers and closely related fields. Artificial Fiber Research Institutes at Kiev and Krasnoyarsk are becoming interested in synthetic fibers. And branches of the YNÎ1Y are now operating at Klin. Kalinin, and possibly other fiber combines. Associated with this burst of activity is greater cooperation with organizations in the Communist satellite countries. In organic synthesis, lor instance, specific tasks are outlined for Soviet and Czechoslovakia!] laboratories in order to avoid duplication of effort. Results of one group's work are sent immediately to the other, with no waiting for publication. For example, in the case of Czechoslovakia the plan involves collaboration in SI projects at 112 laboratories in that country and the Soviet Union. The heads of the Moscow and Prague institutes are in frequent personal contact. Any comparison of fiber research in the U.S.S.R. and the U.S. should take account or papers originating in the satellite nations. On that basis, the total number of papers published on synthetic fiber research and development h greater in the Soviet bloc than in the U.S. The Soviet Union alone
From four monomers, seven fibers... Saniv
-#-
60%
îîîodacrylîc
t
saran
CHa^CCI* Khlorin
40%
~ 100%\.acr^onitrile CH2 = CHCN
t
Soviden
vinylidene chloride
i Nitron acrylic
89%
|ii%
40%
5QO/O
Dyne! modacrylic "*"
modacrylic
CH, = CHCI
J88%
40°o
Kanekaion
vinyl chlonde
Ί
rk being done on heterochain polyamides. Chemists at the institute of Elementorganic Compounds are notable in the attention they give to these, as well as to alternate syntheses of carbon chain polyamides. Polyester
'Research
Lavsan is the So\iet polyester fiber. It is one of the four--die others are Capron. Anid. and Nitron—chosen for \ astly increased production in the
Se\ en Year Plan, Soviet research pa pers on the polyesters show a basic understanding of production methods. But the economy is relying on proven western techniques to increase com mercial production rapidly. Their polyester research pertains mainly to polyethylene terephthalate properties—kinetics of formation, mo lecular weight determinations, and phase behavior. Little is published on fiber spinning or on fiber properties. Here, again, Y. Y. Korshak enters I he picture. He started publishing on polyester resins as far back as 1952. on the exchange reaction when polyester resins ot different molecular weights are mixed and heated. Since then, he has been most active in synthesizing and measuring properties of new polyester resins ov er a broad range. He systematically correlated prop erties with structural features of nu merous polyesters, beginning with the isomeric phthalic adds and diphenv! dicarhoxylic acids of varying ehaai lenuth among the aromaties. eyelies. and aliphatics. Main· of these diverse esters had various types of substituéets on the principal chain. Other Soviet workers plast iei/ed Lavsan by eopolymcri/ing polyethylene terephthalate with the methyl ester of p-ethoxyhydroxybenzoic acid. This produced a fiber that is softer and more dyeable than Lavsan. and it was given the name Okson. its main disadvantage relative to Lavsan is lower thermal sfability. Acrylics and Modacrytics Among Uie acrylic fibers. Nitron was selected by the Soviet planners for greatly increased production. W Y. Mikhailnv. director of the Moscow YNIiY. is active in research on this class of polymers. île first gave details in 1956 of the Soviet physical chemistry studies on polyacrylonitrile in dilute solutions. Many approaches are reported in studying the dyeing problem presented by Nitron when used in wool blends. Also, Nitron spinning technology has been critically re-examined, notably by research groups at the Kalinin branch of ΥΝΊ IY» Other than this, Zaznlina and Rogo\ in reported on a sytUheHc fiber made up mainly of polymethacrylonitrile. Called ΜΊΤ-3. its properties are dis appointingly poorer than Nitron. They did much better on a modacrylic called Saniv. .In 195(y their first re-
REREARCH GROUP. . N I I V Virector r . VV Mikhailov and co-workers watch interface polycondenaatine experimeno np polyamide mixture, , N I I V (All-Union ncientific cesearch I I s t i t u t e for Synthetic Fibers), located in Moscow, recentlo openeb arahches at KliK ana Kalinin, folfowing the erend do f l a c i n g such organizations near fiber combines
port on t h t susstance e a s soncerned witw t h t effect of molecular r e i g h t to an acrylonitrile-vinylidene e0:80 co polpmem r n npinning behavior and other fiber rropertiese The results must have been nneourugigg. A Ae port waw published dt a later r a t e , , i which pilpi otale spinning gf the eiber was described, In western cocntries the eyeability of acrylicsi ,odacrylicsc and polyamides es i s p r o v e d db ydding gmall amaunts sf fitrogen nasas such aa methvl vinvl pyridine to the eolomer. Prof. RoRovin narried dhe edea at oa extreme by producing a fiber m a d e en tirely of that pyridine. The result is s superbly yveable, ,on-exehanging fi ber. No other information no the ma terial hah been published, ThT eoviets sra elso otudying a quite differene type ef mod acrylic, . a acralonitrile-protein fiber. The earli est work showed a a e t h o d for improv ing physical properties snd dyeability of Nitron oiber. They yd thth bb yad i n i gimethyl formamide-soluble graft polpmers of proteins with hcrylonitrile, containing u p to o212 rrotetn, , t ohe spisping solutluno . e , A. Kurilchikov ana his group pt VNIIV Vave e a d e fibers srom mhthe cocolymers and others containing gu to o0rf- rrotein, They've alsa mixed these eopolymers
with hydroxyethylcellulose-acrylonitrile copolymer. The products are said to be wool-like, and they can be dyed llke wools and cottons with con ventional dves since nitrile, amino, aad hydroxy groups are present. Mixeil Polymers,
Too
Basic research on the chlorinated vvnyl ffbers began in 1951 at the IIvnov Insstiute of Chemical Technologv under B. Ε. Geller. After some five years spent on the physical chem ist rv'of perchloroviny! resins, the main eeforr was placed directly on fiber pro ductton ssudies. T h e n , i n 1957, Gel ler publlihed his first report on Khlorin fibbr. He noted that the cloth woven ffom spun staple had exceptional re sistance to chemical attack, but it be ggn to shrrnk at 55° to 65° C. Mikhaiiov and his group at VNIIV weee heard from next. They came up with a ssudy on the mechanism of thermal photochemical decomposition oo the Khlorin polymer. This led to the diicovery that small amounts of cellulose diacetate have a stabilizing effectt The latter, in turn, led to de vvlopment of two new ffbers, The first ii Vinitron, spun from a mixture oo Khlorin and cellulose nitrate in a 11:1 monomer mole ratio; the second
is Acetohhlorin, madb ym mixing 15 to 167c celuulosa acetate into thc chlorin ated polyvinyc chloridi na c common solvent beforsppinning. Mikhailov has said" that thf first mixed polvmer fiberw werm meda at VNIIV i n ' 1951-52. Thia aetedates U.S. pbblicatioi nt thf fielb yy rhree or four years. Thp principlo of com bining two polymer constituentt to produce better fibers is now of pronen valu.. This significant accomplish men,t t h e , t testifiet oo thc competence of Sovief fiber research. The U.S.S..v versioo of a fluoroearbon fibe,, Ftorlons s e e s s t r represent anothrr oolid achievement. De^ velopdd t t Moscow TextilI Institete bv Rogovin anZ Zaznlinai it is spun from an 11 oo 2 2 ^ solutioo ot the polymrr in acetoni inta b b a t c con taining 4 o6 6r/a acetone. Becaese of tts high density, 2.16 g . / c c , its strength per unit ff cro-s-sectional area ss verh high. ThS Soviet Union's popuarr press goeo overboard id ¬e scribing it, using such phrasea as "srrongethhas steela a n " "strongeft fiber ever mdde." F t o r W s compotitioi ik kept out of the literature. DeBniteln nop polvterrafluorethvlenei it ip probablp polvvinvlidenf fluoride, witp possibly some polyvinyl fluorida sc copolym.r. AUG.
7,
9961
C&EN
87
Due to the accelerated growth program at Itek Laboratories, and the opening of new facilities in Lexington, Massachu setts, key positions are now available for:
Colloid
Chemists
A Look at the
Paper Chemists Polvmer Chemists Â1Î degree levels---experience not essential. Work will in¥oi¥e investigation of image forming reactions and study of photochemical reactions. For further
information^
Itek Itek Laboratories
address
your inquiry
T h e Soviets haven't p u b l i s h e d on a Teflon-like fluorocarbon fiber ei their own m a n u f a c t u r e , a l t h o u g h a sintering process for the resin. F t o r o p l a s t - 1 , has been s t u d i e d .
to
Louis Kud^insky Technical P l a c e m e n t Director I Irk Luhoralnrie» 1© Mairuire Koad Levmpton,. Aiassuehusell;* VOI tin leer 2~é'2 00
All qualified appiicanls will receive consideration for empioymen without regard to race, creed, color ox national origin.
Horizon
Ch'aÎt polymerization as a m e a n s for m a k i n g \irtuaIJy n e w synthetic fibers is a p p r e c i a t e d in both Soviet and western fiber research. T h e Soviets use it c o m p e t e n t l y . T h e most promising results seem to lie in grafting d y e a b l e polymers onto strong, hard-to-dye cores, as well as hi r e d u c i n g water sensitivity of the cellulosies. But the t e c h n i q u e s d o n ' t seem to bring about any m o r e economy than does the use of nylons, polyesters, and acrxlics alr e a d y on hand—at least not yet. Neither d o t h e p r o d u c t s seem m o r e useful. In t h e field of " e l e m c n t o r g a n i c " polymers, Profs, K. A. Andrianov and A. A. Z h d a n o v , at the Institute oi Klementorganie C o m p o u n d s , are interested in synthesizing polymers that are stable at elevated t e m p e r a t u r e s and have very high m e l t i n g points, yet which can be d i s s o h e d a n d s p u n from solutions. T h e y vc reported syntheses for polymers of the type -O-M-O-M-O -M-O-
BUYERS' GUIDE Used in 9 8 . 2 % of all process industry research labs to f.nd products fast! Published separately every year in mid-April by Analytical Chemistry. C&EN
AUG.
7,
1961
O
ο
SiiC
SiK,
ο SifC
in which M is a metal of t h e third column ot the periodic system. if M k t e t r a v a l e n t each rnetal of the b a c k b o n e chain has t w o — O—SilC g r o u p s a t t a c h e d . If it is p e n t a v a l e n t , one-4 --Ο—SiH ; . a n d a divalent oxygen satisfy each such c l e m e n t in a back b o n e of a l t e r n a t i n g tri- a n d p e n t a v a lent atoms with interspersed oxygens. Tri-, tetra-, and p e n t a v a l e n t elcmi v nts can also a p p e a r in the4 side chains on t h e s e same metal-oxygen b a c k b o n e s , as in - O - P F C O and - - ( ) - SiR ;j . Con sideling the m y r i a d possibilities in this branch of polymer chemistry, ex cellent fiber formels are likely to exist in this family. W i d e variations can b e p r o d u c e d by c h a n g i n g the organic substitueuts. Andrianov has d r a w n fibers from some of these polymers. T h e combi nations ol chemical and m e c h a n i c a l properties they offer are completely new. O n e i m m e d i a t e l y thinks of t h e possibility of m e e t i n g highlv special ized r e q u i r e m e n t s ol m o d e r n warfare
ARE YOU UP TO DATE ON BENZOTRiFLUORiDES?
JPJLVX PJJL1 Ο Chlorine Benzoyl chloride Benzotrifiuoride
T h u m b through the 12 concise pages of our new d a t a file on these chemi cals for a quick review of the benzotrifluorides> chemical a n d physical properties. Get the latest facts on its o-chloro, w-chloro, arid p-chloro isomers, Learn something new about the score of applications—which range from a lampricide intermediate to pharmaceutical and dye intermedi ates. Other useful facts in this free data file are test results for toxicity, a n d shipping information. Like a copy? Send us the coupon.
FAST WAY TO GET A BENZOYL GROUP
HARD FACTS ON CHLORINE If you'd like 76 pages of hard, fast facts on chlorine, send the coupon for Hooker Bulletin 125. i t tells a lot about the chemical itself, with charts and graphs on phys ical properties. It tells a lot more—about how to h a n d l e chlorine safely. Descriptions of equipment a n d containers should m a k e it easier to r u n a safe chlorinehandling program. Finall} r , there's a listing of the m a n y services you can get from Hooker on chlorine use—services we have developed during more t h a n 53 years of making chlorine.
J u s t pull off a chlorine and there you have it. Our chemical reacts readily. Lets you easily a n d economically place a benzoyl group in an organic com pound—especially through FriedelCrafts reactions. It's 99% pure. Clear, Colorless. It freezes at minus 0.9" C. and boils at 197.3 C C. It distills from 2% to 9 7 % over a 3.5 C C. range, You can buy it in carboys, nickel drums, or non-returnable lacquerlined steel drums, as well as tank trucks or tank cars. For more information on benzoyl chloride's physical properties and also on uses, send the coupon for a data sheet.
For more information» check here and mail with name» title and company address : Π Hooker Bulletin 125 Π Benzoyl chloride data sheet Π Bulletin 12-A, Benzotrifluoride- and its ortho-, meta-, and para-chloro isomers.
H O O K I R . CHEMICAL C O R P O R A f i O N 608-1 Forty-seventh Street, Niagara Falls, Ν, Υ, Sales Offices; Buffalo Chicago Detroit Los Angeles New York Niagara Falls Philadelphia Tacoma Worcester» Mass, In Canada: Hooker Chemicals Limited, North Vancouver, B. C.
HOOKER C H E M I C A L S ·. * PLASTICS '
C & Ε Ν 89
ACE
interchangeable
REACTION APPARATUS
ai tel space technology» Such fibers could represent a Soviet breakthrough. Bnl research publications to date are more indicative of the direction of attack on the problems than the area of accomplishment. These, then, arc areas in which one might assume in tore emphasis in So viet fiber reseaich—graft polymeriza tion and "οίοηϊοηίοι^ίΐηκ/* polymers. As in the U.S., the use of graft poly merization for obtaining an optimum combination of properties is a most immediately interesting field of study. Research along these lines will take utmost advantage of a groundwork of knowledge ahead)' at hand, In the elementorganic pohmers we have a ditlcrent situation, an approach to new fibers that would be exciting if only because it is relatively un charted. But, more than this, one can only anticipate the possibilities for ultraperformance materials that He in this direction ι. So far, the nature of the concept is a peculiar!) Soviet one. if there is any area of great divergence between Soviet and U.S. synthetic fi ber research, this is it. The difference is not a question of their approach compared to our approach. The dif ference is simply that they are deeply committed in this area of research while, so far as is commonly known, we have lurch touched it. The advances being made by the Soviet Union in synthetic fiber research may not be comparable to advances in other areas of chemistry. But we should not underestimate the amount of special effort they are putting into this field of research. In the U.S.S.R. today the technical needs of the fiber scientist are getting preferred treat ment, and his findings are getting spe cial attention. He and the Soviet Union Ν economic planners think in terms oi fibers that are currently non» existent Perhaps we should do no less.
for research & PRDUCTION Bottoms, Tops are available in stainless steel# Monel and other metals as well ct$ glass. The 1 t o 72 litre range permits use for bench top opplî* cations as well as pilot plants and small batches; the 5 0 to 72 litre size proven ideal f o r specialized pharmaceutical and biological compounds.
All lops are interchangeable with all bottoms regardless of size Experiments can be carried out with only one top and et series of bottoms ranging from 1 litre to 72 litres* Necks are wide, facilitate cleaning of viscous material· In addition to standard heads, Ace will custom make to your specifications.
Ace Reaction Apparatus
Standard clamp adaptable to entire series of reaction flasks. Top section removable without disturbing lower section* Convenient arm for clamping t o supporting frame, Hammertone finish. Full line of accessories: Glas-Col Heaters Powersîats Trubore Stirrers Stirring Motors*
REPRINTS . . .
α ίυίίγ described m Ace Brochure 58,
Wriie Depfr C for your copy.
ACE Louisville, Ky.,
GLASS I N C O R P O R A T E D
Vineland N. J. S p r i n g f i e l d ,
Mass.
. . . of this article, combined with that which appeared last week, are avail able at the following prices: one to nine copies—$1,00 each 10 to 49 copies—15% discount 50 to 99 copies—20% discount Prices for larger quantities on request Address orders to Reprint Depart ment, ACS Applied Publications» 1155 18th St., N.W., Washington 6, D.C.
DIRECTORY This section includes: CHEMICALS KXCH AX( ;E—Cheni irais, Resins. Chillis, Oil·?. Waxes, Pigments, e t r . ; EiJUIPMKXT MART —Xew nn,.,, 400 PSpFac. packed, $ | J 50 type 304, 16 sauge,
N o . 5OS, ur c r d i i REAGENTS KIT No. 505 -$10.00
ο ω -m 3 4>. Φ
2 ο
:opïes
m
ω b ο
•m
ces b
Research · Development · Testing Toxicology · Evaluations · Pharmaco J ogy Microbiology · Chemistry · Trace Element, Tissue Residue, Food Additive» Isotope Studies l i rile for Hn»'hnn HARRIS LABORATORIES, INC. P. O . B o x 4 Î 7 # L i n c o l n 1 , N e b r a s k a M e m b e r : Amor. Council of Independent Laboratories.
"Ό 2 "Ό
ill in the s
Send for information 1Î7 H A W T H O R N E
Assays
ncl
J. S
Pharmaceyfical Hormone
ivisio
W r o b ! / w , M . F , Λ f ciDc,
Toxicity
with
2.
Toxicity
Cosmetic
rice:
MB,B,B,BBKGKHHJKGKG KGGGGKGGKGKKGKGK
Φ
Industrial
DONT WASTE iOMENTS OR MOTION! j u s t fill out and post For the most prompt receipt of the most recent book of I1STIICTS OF MEEÏiie PJtPEIS Chicago, September 3 8, 1961 end
The attention of Industrial Physicians b directed to recent reports n · - ' of increased Serum Trans aminase >'SGO-Ti levels following exposure to cer tain chemicals: although these studies are still i n early stages, they seem to indicate a great diagnostic value to the routine and emergency determinations of S G O - T .
Rci:
TECHNICAL SERVICES
AfHilvfis ofOniutiir (To//m/.i. fb-SiiJh itifftin oitr uwk. Elements» f u n c t i o n a l G r o u p s , M o l e c u l a r W e i g h t s , P h y s i c a l Constants, Spectra. A n a l y s i s of Boro-FloorO; and Silicon Compounds Trace A n a l y s i s
Fold on above line. Mail in window envelope or use your own plain enveiope with this address.
MICROANALYTICAL RESEARCH 5 6 - 1 9 37th A v e . , W o o d s i d e 7 7 , N e w York T.4i*t»»«·»,·: I I \ Λ Ο Π Ι Ο > * Μ · l M>2 I B , * M i 2 2 i t
BROWN COMPANY, C H E M I C A L PRODUCTS DIV. Berlin» New Hampshire
4^ Ο
"Chemistry of Lifef? Reprint
"f||go.YViÉ«*ii-ia " " " ^ Ox v$£«»n- § 1 G A s
^o(j
L4BflLr
_0
COMPOUNDS
ΥΕ0Α Res,»Si.Lh .ind D.ncΙορτηο·ηΙ Cu. LUI. «t the W c ' f f l J i w tnsKt.it» at Scicnvf
RCHÛVOTH. ISRAEL
You may still order reprints of this popular
series
which
appeared
in
AVAILABLE IN RESEARCH for prices
other
research
QUANTITIES
and listing
of
chemicals
the ways in
which research is helping to explain how
genetic
information
is
trans
mitted by specific nucleic acids, how the human body converts amino acids to
TECHNICAL SERVICES
protein, and how life on earth
originated.
> ω S -Ό m m 70 O
ο
>
3
ζ
m 5 o m c I m ρ m m m ρ 2
?
SALE ifCAl SOCIETY
n Write
discuss
t_j
Η*
m tu Ξ*. m
ngton
1CT1VITE0 MANGANESE DIOXIDE
three articles
Ù)
Sixtee
C&EN of Way 8, 15 t and 2 2 . The
^
SI IV!
_—-
3
Φ
m
φ "Ό "D
m
3 0Ό
Prices for the 28~page combined lOon^
since 1922 •»©^
