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 A B O T C O R P O R A T I O N DEPT. CNH, 125 HIGH STREET, BOSTON, MASS. 02110 (617) 423-6000
how to prevent settling with
CAB-OSIL Increase product uniformity, attractiveness, and eliminate the need to "shake well before u s i n g . " Avoid the sales losses which result from having quality formulations classified as " c h e a p " because solids or liquids separate. Save handling, mixing, and clean-up time when settling occurs in drums or tank cars. Maintain stability over wide temperature 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 " c h i c k e n - w i r e " 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 therefore 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 " b r i d g i n g " 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 information 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 D e p t C N 1 1 , 125 H i g h Street, B o s t o n , Mass. 02110
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D RUSH FREE SAMPLE and literature on CAB-O-SIL D Please call me for appointment. Tel.: I am especially interested in
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Company Address Calamine Lotion — With 3 % CAB-O-SIL, 9 7 % of the solution remained in suspension after 3 0 days.
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