BENTONE 27 rheological additive is an organic derivative of a hectorite clay.
BENTONE 27 is designed for moderate to high-polarity organic systems and for synthetic binders.
BENTONE 27 rheological additive for lubricating grease manufacture.
Product Name: Stearalkonium hectorite
Synonyms: Bentone 27;Bentone 27V; Bentone Gel SS 71V
CAS Number: 12691-60-0
BENTONE 27 is specifically designed to improve thickening efficiency in synthetic and other organic fluids of medium- to high-polarity.
BENTONE 27 rheological additive is a modified hectorite organoclay for use in high polarity aromatic and oxygenated solventborne paint and coating systems.
BENTONE 27 is an organic derivative of a hectorite clay.
BENTONE 27 increases viscosity.
BENTONE 27 provides thixotropy.
BENTONE 27 acts as a rheology modifier for medium to high polarity systems and for synthetic binders.
BENTONE 27 provides sag resistance on vertical surfaces and penetration on porous substrates.
BENTONE 27 improves flow and leveling and prevents pigment settling during storage, and prevents syneresis in thixotropic systems.
BENTONE 27 is used for anti-corrosive paints, anti-fouling paints, foundry moulds paints, gravure and flexographic printing inks, industrial finishes, and wash primers.
BENTONE 27 has a shelf life of 4 years.
Applications of BENTONE 27:
BENTONE 27 is an effective gellant for esters, vegetable oils, polyalkylene glycols and certain silicone fluids.
Attributes of BENTONE 27:
BENTONE 27 rheological additive
• Ease of manufacturing
• Resistance to melting
• Resistance to oil separation
• Excellent worked stability
• Wide range of temperature applications
Chemical and Physical Data about BENTONE 27:
Composition - organically modified hectorite clay
Color – creamy white
Form - finely divided powder
Density - 1.80 g/cm³
Moisture – 3% Maximum
Incorporation of BENTONE 27:
Equipment:
BENTONE 27 rheological additive can be readily blended into oils and fluids using normal grease equipment.
BENTONE 27 produced must be sheared through a colloid mill or homogenizer to obtain maximum yield.
Process:
Grease is generally manufactured at room temperature and requires no heat for the gelation of the oil.
The normal process briefly is:
1. mix the BENTONE 27 into a portion or all of the base fluid
2. add a suitable polar activator* such as propylene carbonate, methanol or acetone
3. mix until a significant increase in viscosity occurs
4. add the remaining base fluid (if less than the total amount was used initially) and any other desired additives
5. mill
*Polar Activators:
Below are common polar activators with typical starting point use levels.
Polar activator level should be optimized for each grease formulation.
Use range based on Weight of Organoclay:
Acetone 25 - 40%
Methanol/H2O 95/5 7 - 20%
Ethanol/ H2O 95/5 12 - 28%
Propylene Carbonate 8 - 25%
BENTONE 27 rheological additive is an organic derivative of a hectorite clay.
BENTONE 27 is designed for moderate to high-polarity organic systems and for synthetic binders.
KEY PROPERTIES
- BENTONE 27 rheological additive: increases viscosity; provides thixotropy; prevents pigment settling during storage; improves flow and leveling; controls sagging on vertical surfaces and penetration on porous substrates; prevents syneresis in thixotropic systems
CHEMICAL & PHYSICAL PROPERTIES of BENTONE 27:
Composition: organic derivative of a hectorite clay
Color / Form: Off-white to white powder
Density: 1.8 g/cm³
Moisture: max 3.0 %
APPLICATIONS of BENTONE 27:
- Adhesives and mastic compounds
- Anti-corrosive paints
- Anti fouling paints
- Cosmetics
- Foundry mould paints
- Gravure and flexographic printing inks
- Industrial finishes
- Plastisols, organosols
- Wash primers
BENTONE 27 is an organic derivative of hectorite clay.
BENTONE 27 is used as a rheology modifier: increases viscosity, provides thixotropy, improves flow and leveling, prevents pigment settling during storage, and prevents syneresis in thixotropic systems.
BENTONE 27 is designed for solvent-based systems with moderate to high polarity, as well as for synthetic binders, adhesives and mastic compounds.
KEY PROPERTIES of BENTONE 27:
- Increases viscosity
- Provides thixotropy
- Prevents pigment settling during storage
- Improves flow and leveling
- Controls sagging on vertical surfaces and penetration on porous substrates
- Prevents syneresis in thixotropic systems
BENTONE 27 is a modified hectorite organoclay for use in high polarity aromatic and oxygenated solventborne paint and coating systems.
KEYWORDS:
12691-60-0, Stearalkonium hectorite, Bentone 27V, Bentone Gel SS 71V, Bentone 28, Bentone 34, Bentone SD1, Bentone P 380, Bentone EW, Bentone STG 146
INCORPORATION of BENTONE 27:
General:
Incorporation of BENTONE 27 in organic systems (e.g. paints) requires high-shear dispersion equipment and a chemical activator.
Two basic incorporation methods can be used:
1. Addition of BENTONE 27 as a dry powder for in-situ dispersion and activation
The BENTONE 27 powder is added directly to the resin/solvent blend and is thoroughly mixed for 10 minutes.
A chemical activator (see below) should be added next and mixed for 10 minutes.
The pigments and fillers are then added and dispersed with high shear for at least 15 minutes.
2. Addition of BENTONE 27 as pregel of 5 –10% by weight
The solvent is charged to the mixing tank.
BENTONE 27 powder is added and dispersed under high shear.
A chemical activator can then be introduced to optimize gelation (see below).
For incorporation in the full formulation the pregel is added to the resin/solvent mixture with stirring.
Pigments and fillers are then incorporated and dispersed under high shear.
For more details see Rheology Handbook.
Suitable dispersion equipment:
High-speed disc impellers (Cowles dissolver);
Ultra-Turrax, pearl-, sand-, ball- and three-roll mills.
Chemical activators:
Recommended to ensure full activation, i.e. optimum efficiency of BENTONE 27.
Suitable chemical activator % based on weight of dry BENTONE 27:
Methanol/H2O (95/5) 33 %
Propylene carbonate 33 %
Propylene carbonate/ H2O (95/5) 33 %
Ethanol/ H2O (95/5) 50 %
Acetone/ H2O (95/5) 60 %
Levels of Using BENTONE 27:
Typically 5 - 8 % BENTONE 27 rheological additive is required.
A concentration loading study is recommended to optimize the level of addition.
LEVELS OF USE:
The level depends on the system in which BENTONE 27 is to be used.
In paints of intermediate or high polarity, typical levels range between 0.2 and 1.0 % BENTONE 27 (dry) based on total system weight. In synthetic resins (epoxy, polyester), quantities to be added are between 0.5 and 1.0 %.
HEALTH AND SAFETY of BENTONE 27:
Before using BENTONE 27 please consult our Safety Data Sheet (SDS) for information on safe handling and storage.
The SDS can be found on the company website.
Health and Safety of BENTONE 27:
Before using BENTONE 27 please consult our Material Safety Data Sheet.
STORAGE RECOMMENDATIONS of BENTONE 27:
Store BENTONE 27 in a cool, dry location.
SHELF LIFE of BENTONE 27:
BENTONE 27 has a shelf life of 4 (four) years from date of manufacture.