MARKETS - C&EN Global Enterprise (ACS Publications)

Versatile CMC sports the right inverse proportion: production going up; prices ... Even in Germany it remained a laboratory curiosity until the late 1...
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MARKETS CELLULOSE G U M A N D TECHNICAL GRADE CMC PRICE TRENDS 1944-1953 WHOLESALE PRICE INDEX ** (CHEMICALS) INDEX - 1944 - 10O

CELLULOSE GUM AND TECHNICAL GRADE CM\DE C M C PR ICES

50

k

45

!

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CURRENT P R I C E 3 9 cents

\

\-

\ '

40

1945

Î946

1947 4

COMMOD ITY

*

1948

1949

1950

1951

1st 6 1952 Μοβ. Αν 1953

1953

U. S BUREAU OF LABOR STATISTICS

. R. HAROLD JENKINS, JR., Hercules Powder Co., Wilmington, Dei

CAItBOXYMETHYLCEtLULOSE Versatile C M C sports the right inverse proportion: pro­ duction going up; prices d o w n . It is expected that this wili lead into n e w e r a n d even more diversified markets. 3310

CHEMICAL

AND

ENGINEERING

NEWS

A HE newest addition to the family of commercially" significant cellulose derivatives, caxboxymethylcellulose, has been widely accepted b y industry because of the unusual versatility of its properties, spuch as aqueous solution thickening, solids suspending, emulsion stabilization, and film formation. While carbaxymethylcellulose itself is not new, a patent having been issued in Germany in 1918, it has been available in this country i n commercial quantities fox less than 10 years. Even in Germany it remained a laboratory curiosity until the late 1930's when it was discovered that carboxymethylcellulose was useful in promoting detergency. This property was widely utilized during World War II b y the Germans to help supplement their critical supply of fatty acids used in soaps. In addition, Germany, as well as other European comntries, pioneered the use of carboxymethylcellulose in adhesives, textile sizing, solution thickening, and other applications as a starch replacement. The first significant commercial production im this country was started around 1944 by Hercules. Today D u Pont and Wyandotte, as well as Hercules, are all producing this material. D u Pont anS from 0.7 to the vicinity of 1.2 will c a u s e a decrease in 1% vis­ cosity to t h e range of 100 to 300 cps. Keeping t h e DS constant at 0.7, b u t lowering t h e DP to the low end of the range will reduce the resulting water viscosity t o less than 100 cps. Thus it is impossible to vary the viscosity of t h e CMC over quite a broad range b y control of these variables. T h e basic properties that make C M C of commercial interest are its ability to thicken water, to suspend solids in aqueous media, to stabilize oil-water emulsions, and to form water-soluble films. These properties are utilized in such widely divergent applications as detergents, adhesives, oil-well drilling m u d s , latex paints, textile sizing and printing, calender stack and beater ad­ dition to paper, ceramic glazes, soil conditioning, and laundry sizing. In t h e pharmaceutical field, the purified cellulose g u m finds application in bulk laxatives, obesity aids, pharmaceutical suspensions, and other relative prod­ ucts. A few of the newer developments that are of considerable interest at present axe the use of C M C as a wall­ p a p e r adhesive, as a soil conditioner, and as a fabric size, with particular emphasis on the specialized field of laundry frnishes. Soil Conditioner Potential

While not as widely publicized as t h e polyacrylate type soil conditioners, field studies currently being carried out a t various agricultural colleges in­ d i c a t e that C M C is equivalent in every way i n conditioning problem soils, such as clay c*r high clay-content soils t h a t crust badly. When properly applied, C M C acts to improve the structure of these problem soils to facilitate better seedling emergence. The problem of resistance to microbial deterioration has been overcome by the utilization of t h e higher substituted C M C types, since past tests indicate that t h e higher substituted C M C types are resistant to such degradation. Stainless W a l l p a p e r Paste

T h e recent demand for deep-toned w a l l p a p e i in homes has emphasized t h e need for a wallpaper adhesive that can b e removed from the paper without leaving t h e stains that are apparent with conventional pastes. This need for a noostaining type of adhesive has led t o the use of CMC for this applica­ tion. Simce C M C is water-soluble, any adhesive stains appearing on the wall­ 3312

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