L A B O R A T O R Y R E P O R T N O . 11 O X I D E S D I V I S I O N
CABOT C O R P O R A T I O N
DEPT. CN11, 125 HIGH STREET, BOSTON, MASS. 02110 (617) 423-6000
how to prevent settling with
CABOSIL Increase product uniformity, attractiveness, and eliminate the need to "shake well before using." Avoid the sales losses which result from having quality formulations clas sified as "cheap" because solids or liquids separate. Save handling, mixing, and clean-up time when settling occurs in drums or tank cars. Maintain stability over wide tem perature differentials. Small amounts of CAB-O-SIL achieve stability in most liquid systems. It increases viscosity and thixotropy by locking solid particles in suspension through hydrogen-bonding of the CAB-O-SIL particles. The hydrogen-bonding process causes the chain-like structure of CAB-O-SIL to group into a "chicken-wire" pattern which entraps solid particles or liquids having different characteristics. The degree to which a liquid responds to this phenomenon depends primarily upon its polarity. Non-polar liquids do not hydrogen-bond and therefore permit the groups of CAB-O-SIL particles to hydrogen-bond to each other. These liquids require very little CAB-O-SIL to achieve suspension. Typical liquids are toluene, mineral spirits, mineral oils and carbon tetrachloride. About .05 to 2 % CAB-O-SIL by weight will usually hold solids in suspension. Liquids which have medium or high polarity are capable of hydrogen-bonding to the CAB-O-SIL particles, and there fore more CAB-O-SIL is required to achieve suspension. Among these liquids are water, ethanol, ethyl acetate, methyl ethyl ketone and glycerol.
Effect of CAB-O-SIL on settling characteristics Of chromium oxide green in oil.
HOW ADDITIVES WORK
Additives intensify the suspension efficiency of CAB-O-SIL by providing additional hydroxyl groups for hydrogenbonding. The most effective additives have a short carbon chain (not over 4 carbon atoms), and at least two sites for hydrogen-bonding to the CAB-O-SIL surface. Additives, by their "bridging" action between CAB-O-SIL particles, also tend to improve stability on aging. Try CAB-O-SIL in your product to achieve improved stability and uniformity. Mail the coupon below for more informa tion and a sample for evaluation. Examples:
ADDITIVES INCREASE EFFICIENCY
The amount of CAB-O-SIL needed to prevent settling in polar liquids can be reduced from 1 5 % - 2 0 % to l % - 3 % by weight of the total system, if about l % - 3 % of a nonionic surfactant such as polyether alcohol, or a cationic surfactant like quaternary ammonium chloride, is added.
Interior Enamel Paint — 0.08 lb. CAB-O-SIL per gallon showed no pigment settling after 5 months. Alkyd Resin Primer — Showed no settling after 6 months with 0.08 lb. CAB-O-SIL per gallon. Aqueous Suspension of Ti0 2 — 0.4% CAB-O-SIL, 0.4% Marasperse additive and 0.2% Arquad 2S-75 additive eliminated settling. Tranquilizer Capsule—Pellets dispersed in corn oil settled within a few weeks, whereas 3 % CAB-O-SIL plus 0 . 1 % glycerol maintained suspension. C A B O T C O R P O R A T I O N - O X I D E S DIVISION Dept. CN11, 125 High Street, Boston, Mass. 02110 D RUSH FREE SAMPLE and literature on CAB-O-SIL Π Please call me for appointment. Tel.: I am especially interested in
NameTitle— CompanyAddress—
Calamine Lotion — With 3 % CAB-O-SIL, 9 7 % of the solu tion remained in suspension after 30 days.
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