Eastman takes a look at the second law of thermodynamics
T
hose who find themselves able to look at things philosophically may recognize that the problem of deterioration of materials is but a troublesome manifestation of the second law of thermodynamics. Because heat, UV radiation and other agen cies in this restless portion of the universe have a habit of knocking electrons out of place, and because such wayward particles rarely seem to bode well for man, the reactions they initiate mostly end up with valuable substances being degraded, dispersed and destroyed. The neatly engineered fuel cut, the ingeniously wrought polymer, the lovingly prepared food—all appear fated to go to perdition before our very eyes and noses. And the work expended in developing these products—where does it go but to the uni versal heat sink? If this doesn't represent an in crease in the general randomness and cussedness of things, we'll eat a rancid cupcake. Rather than organize a "Ban the Second Law!" movement, though, we at Eastman have
ing foods, feeds, drugs and packaging materials. Tenox® BHA, Tenox BHT and Tenox PG are our desig nations for food-grade butylated hydroxyanisole, butylated hydroxytoluene, and propyl gallate. Without peer in guarding the flavor, bouquet and appearance of co mestible products, they operate by acting as proton donors, in effect short-circuiting the autooxidative cy cle. Carbonyl content stays down, palatability remains high. As one man's meat is not often like another's, Eastman supplies these antioxidants alone and in many different ratios and combinations—Tenox 2, 4, 7, R, S-l and others—to meet specific processing requirements. We also sell technical BHT (we call it Tenamene® 3.) But see the next section for more on fuels. S u b s t i t u t e d Amines— excellent as gum inhibitors, sweetening catalysts and metal deactivators in petro leum distillates, and as antiozonants in elastomer stocks. The first of these compounds, N-butylated-p-aminophenol or Tenamene 1, could as well have been included among the phenols, except that its rather toxic nature more logically places it here. Two of its congeners are Tenamene 60 and Tenamene MD 50, chemically disalicylalpropylenediimine, which find wide use as metal de activators in liquid fuels. The others in this group are all substituted p-phenyl-
directed our efforts towards more productive and profitable ends: the manufacture and sale of a wide variety of antioxidants, inhibitors, anti ozonants and stabilizers. On these pages you will find a brief discussion of these species, and a few hints on where you can use them in your own personal battle against increasing entropy. S u b s t i t u t e d Phenols—particularly useful for prevent ing rancidity and other oxidation effects in fat-contain-
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Name
Substituent Groups
Function
Tenamene 2
N,N'-di-sec-butyl
Antioxidant, sweetening agent
Tenamene 4
N,N'-bis-(l ,4-dimethylpentyl)
Antioxidant,
Tenamene 5
Ν,Ν'-di-isopropyl
Antioxidant,
sweetening agent sweetening agent Eastozone®30 N,N'-bis-(l-methylheptyl)
Antiozonant
Eastozone31
N,N'-bis-(1-ethyl-3-methylpentyl)
Antiozonant
Eastozone 33
N,N'-bis-(l,4-dimethylpentyl)
Antiozonant
Eastozone 34
N-phenyl-N'-isopropyl
Antiozonant
and otters some thoughts on the degradation or materials ene-diamines. The alkyl, or alkyl and aryl substituent groups are indicated below. Variations in efficiency and
economy make the several substances suited to particu lar refinery or rubber plant operations. Qllinones— eminently suited to the needs of those seeking polymerization inhibitors and shortstops. t-Butylhydroquinone, p-benzoquinone and just plain old hydroquinone (we call our technical grade Tecquinol®) are rather good polymerization inhibitors for un saturated polyester systems. Another that we sell, 2,5diphenyl-p-benzoquinone, is specially good for isophthalates. For inhibition of acrylic and vinyl monomers we offer the well known hydroquinone monomethyl ether. And finally, for those who want to use them as is, or in the synthesis of more formidable antioxidant molecules, there are toluhydroquinone and 2,5-di-tbutylhydroquinone. 2 - H y d r o x y b e n z O p h e n o n e s — where the materials to he protected are plastics and where the culprit is light. When opacity, intense color or high fluorescence are of little consequence, carbon black or a light stable, in tensely fluorescing dye such as 6,13-dichloro-3,10-diphenyldioxazine may be used to protect polymers from actinic degradation. Where clarity and low color are important for reasons of function or fashion, however, the answer may not be found so readily. For chemists in
this fix we offer some 2-hydroxybenzophenones. These substances perform excellently, absorbing the offending quanta of short wave radiation and harmlessly dissipat ing the energy via resonating chelate structures. East man sells Inhibitor DOBP (4-dodecyloxy-2-hydroxybenzophenone), Inhibitor OPS (p-octylphenyl salicy late), and Inhibitor RMB (resorcinol monobenzoate). These last are really more than kissin' cousins—under the influence of UV they rearrange to 2-hydroxybenzo phenones. O d d Ball—there is one in every family. Ours is called Inhibitor HPT—hexamethylphosphoric triamide. In terms of molecular orbital theory we are still not sure how it functions, but we know it's good: after seven years on our rooftop a piece of HPT-stabilized PVC strip was still in fine condition. And we get a fair amount of sunlight at Kingsport.
As you very well know, there is a lot more to maintain ing the chemical and physical integrity of materials than merely adding a dash of this or a pinch of that. As a first step in your quest for the right antioxidant, inhibitor or stabilizer, therefore, you ought to get in touch with Eastman for advice as well as for samples. Tell us as much as you can about your particular problem. It will save time for us both, and will help us do a better job for you. Send your letter to Chemicals Division, Eastman Chemical Products, Inc., subsidiary of Eastman Kodak Company, Kingsport, Tennessee.
Eastman ANTIOXIDANTS AND
STABILIZERS
SALES OFFICES: Eastman Chemical Products, Inc., Kingsport, Tennes see; Atlanta; Boston; Buffalo; Chicago; Cincinnati; Cleveland; Dallas; Detroit; Greensboro, North Carolina; Houston; Memphis; New York City; Philadelphia; St. Louis. Western Sales Representative: Wilson & Geo. Meyer & Company, San Francisco; Los Angeles; Salt Lake City; Seattle.
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