121st NATIONAL ACS MEETING—MILWAUKEE acids, alcohols, and carbonyl compounds, with yields decreasing as t h e n u m b e r of carbon atoms increases over five. T h e relation of reaction m e c h a n i s m s to t h e production of materials covered in these four product papers was explained by A. W . Weitkamp, S t a n d a r d Oil, as a series of competing and concurrent reactions, roughly classified as initiation, chain extension, and termination. Vapor-Liquid Equilibria. F u n d a m e n t a l data on vapor-liquid equilibria for binary hydroearbon-water systems a n d t h e system propane-water h a v e been studied by Riki Kobayashi and Donald L. Katz at the University of Michigan. A correlation was shown b y Dr. Kobayashi, n o w at T h e Rice Institute, for dealing with these hydrocarbons when saturated with w a t e r , which should b e of value in such p l a n t problems as fractionating, drying, and pipeline transmission. Houdriforming Reactions. Studies of the Houdriforming reactions, where use of a dual-function catalyst allows achievement of more t h a n o n e reaction at once, have been m a d e in detail b y the Iloudry Processing Corp. Explanation of these reactions, believes Heinz H e i n e m a n n , lies in their occurrence on two "sites" on the catalyst, one where isomerization takes place, a n d a second which can hydrogenate a n d d e h y d r o g e n a t e , with transferal of an olefin intermediate b e t w e e n these sites on the catalyst. Details of catalyst composition, w h i c h would h a v e contributed considerably m o r e to the interest of the papers, were n o t revealed. Propane-Butane Pyrolysis. T h e literature has not h a d a single, complete picture on kinetics, product composition, and other phases of thermal decomposition of p r o p a n e a n d the b u t a n e s at high pressures, and this situation has b e e n remedied by IT. J. H e p p and F . E. Frey, Phillips Petroleum Co. Detailed yields w e r e reported b y Mr. H e p p , including composition of the gasoline fractions, l i e noted that the first products are olefins, which are polymerized and alkylated to form products of higher boiling point than the parent hydrocarbon. Gasoline products are next, followed by tar and coke, and coke formation necessitates stopping the reaction long before complete destruction of t h e original material is attained. C a t a l y s t Size Effects. Mass transfer rate is actually a limiting factor inside catalyst granules greater than about 0.02 inches in diameter, making t h e inner portions of t h e catalyst less effective than the outer. T h i s conclusion was reached, said V. C. F. H o l m , Phillips Petroleum Co., after studies of b u t a n e dehydrogenation over chromia-alumina catalyst at 530° C. and hydrogen transfer over silica-alumina at 340° C , for several sizes of granules. Mass transfer of b u t a n e from t h e inner portions of t h e silièa-alurnina catalysts was followed by saturating t h e catalyst with butane labeled w i t h radioactive carbon, passing unlabeled b u t a n e over t h e catalysts, a n d measuring t h e r a t e of appearance of radioactivity in t h e effluent.
1524
D I V I S I O N O F POLYMER C H E M I S T R Y
Interest in Blood Plasma Substitutes Spurs Research in Polymers • Refined techniques aid in elucidation of structure, open new avenues of research • First single nucleic acid molecule shown as aid in chromsome investigations Χ H E possible physiological a n d p h a r m a cological applications of water soluble polymers, particularly the blood plasma substitutes a n d t h e nucleic acids (constitu ents of c h r o m o s o m e s and g e n e s ) , has led to intensified research on these products. In a review of recent progress, t h e Divi sion of P o l y m e r Chemistry, jointly with the Division of Colloid Chemistry, organ ized a S y m p o s i u m on W a t e r Soluble Poly mers of Biological Interest. Charles O. Becknumn, C o l u m b i a University, presided over the o n e - d a y session which h e a r d some of t h e older m e t h o d s of starch and glyco gen research a d a p t e d to t h e p r o b l e m s of the newer c o m p o u n d s with m a r k e d suc cess. As a s i d e l i g h t to his p a p e r , R. Mont gomery of t h e University of Minnesota pointed out that improved techniques were beginning to turn u p small residues the significance of which may have im portant b e a r i n g on polymer theory. As ne\vt*r m e t h o d s b e c o m e more specific and more accurate, the purity of t h e com pounds w e work with will b e c o m e in creasingly iinportant, h e a d d e d . Structure by Enzymes. Specific en zymatic a c t i o n was used b y J. L a m e r and Gerty T. Cori, W a s h i n g t o n University, to establish t h e validity of t h e regularly branched s t r u c t u r e for glycogen and amylopectin first proposed by Meyer. In addition. Dr. L a n i e r , stated that their method iiulic-ates t h e existance of regular, alternate tiers of 1,4 and 1,6 branch points. In their experiments, t h e limit dex trin p r o d u c e d b y t h e action of phosphoryT h e b r a n c h e d structure for amylopectin and glycogen p r o p o s e d by J. L a m e r and G e r t y Cori of Washington University. T h e figures i n d i c a t e tiers of b r a n c h points
CHEMICAL
lase (specific for 1,4 linked glucose chains) was t r e a t e d with glucosidase to p r o d u c e a limit dextrin in w h i c h 1,6 glucose chains had b e e n attacked. This procedure could be r e p e a t e d to obtain as m a n y as four consecutive limit dextrins, corresponding to 90
