Ultrasonic Dispersion of Xanthan and Guar Gums
- Shear-thinning materials such as xanthan gum and guar gum are widely used as rheological modifiers.
- In order to take full advantage of the properties of xanthan gum or guar gum, the powders must be uniformly dispersed in the formulation.
- The intense high shear forces of ultrasonics is a reliable method to blend xanthan and guar gums into homogeneous product formulations.
Ultrasonic Formulating of Xanthan and Guar Gums
Xanthan and guar gums are frequently used as rheological modifiers, thickeners and stabilizers. Both, guar gum and xanthan gum are very economical rheology additives due to their high water-thickening capacity. The viscosity of xanthan gum and guar gum solutions decreases with higher shear rates; this is called shear-thinning or pseudoplasticity. This means that a product subjected to shear, whether from mixing or shaking, will thin out, but, once the shear forces are removed, the product will thicken back up. The combined use of xanthan gum and guar gum shows synergetic effects resulting in an even more efficient and faster viscosity built-up.
To integrate xanthan gum and guar gum efficiently and fast into formulations, e.g. drilling fluids, food or cosmetics, the powders must be homogeneously dispersed and blended. Conventional agitators and dispersers often reach their limits when it comes to viscous slurries with high particle loads. Clumping of powders, also referred to as “fish-eyes”, result in low product qualities as particles can enfold their characteristics only in a single-dispersed state.
Ultrasonic shear forces are a reliable method to disperse shear-thinning materials into slurries. High particle loads, high viscosities and high volume streams can be easily processed by ultrasonication. For commercial manufacturing, ultrasonic homogenizers are installed inline for continuous slurry processing. As the particles are fed directly into the cavitational zone, a reliable and efficient dispersion is achieved.
Ultrasonic blending saves you time and money!
- Less raw material
- Very uniform dispersion
- High quality products
- Fast dispersion
- High particle load
- High viscosities
Ultrasonic Blending & Dispersing
When intense ultrasonic waves are induced into liquids and slurries, the alternating high pressure and low pressure cycles generate cavitation bubbles. The implosion of these bubbles create locally extreme conditions – so-called hot-spots – that are characterized by high pressure differentials, high temperatures of up to 6000K, high cooling rates and liquid jets of up to 280m/s. These extraordinary ultrasonic forces can be effectively used for various applications such as milling & grinding, dispersions, emulsions and disintegration.
Hielscher’s range of ultrasonic high-shear mixers offers the suitable device from lab and R&D to full-industrial production. Ultrasonic disperser can be installed as in-line systems to process high volumes at high dispersion rates. Industrial ultrasonicators such as the UIP4000, UIP10000 or UIP16000 are designed for heavy duty applications in demanding environments – convincing by their robustness and efficiency.
Due to their excellent properties as rheological modifiers, xanthan gum and guar gum are widely used in manifold industrial sectors. To make full advantage of their material’s characteristics, xanthan and guar gum must be evenly mixed into the formulation. Ultrasound is a fast and reliable technique to prepare a homogeneous formulation on lab, bench-top and industrial scale. As well as xanthan and guar gums are widely used in many industries, likewise ultrasonicators are used in manifold industries and are highly recommended due to their outstanding high shear mixing.
Use of Xanthan Gum
Oil Drilling Industry:
Preparing drilling fluids, the oil industry used xanthan gum in large quantities, usually to thicken drilling mud. These fluids serve to carry the solids cut by the drilling bit back to the surface. Xanthan gum provides great “low end” rheology. The viscosity of the drilling fluid increases when movement decreases, allowing the fluid to have a liquid consistency when drilling is occurring and then turn into a more solid substance when drilling has stopped.
Xanthan gum is a frequent additive used in processed food such as salad dressings, sauces, soups, and baked goods. Gluten can be excellently substituted by xanthan gum. Therefore, xanthan gum is an important ingredient in gluten-free products.
In cosmetics, xanthan gum is used to prepare water gels, usually in conjunction with bentonite clays. For example, it is a very typical thickener in shampoos. It is also used in oil-in-water emulsions to stabilize the oil droplets against coalescence. It is also known for its skin hydrating properties.
Use of Guar Gum
The food industry consumes the largest part of guar gum (known as food additive E412) and are frequently for gluten-free products.
Oil Drilling Industry:
Besides xanthan gum, guar gum a frequently used rheological modifier as ist builds up viscosity and has a very good water-thickening potency. Used as stabilizer, guar gum prevents particles from settling.
Other industry branches which use guar gum include the textile industry for sizing, finishing and printing, the paper industry for improved sheet formation, folding and denser surface for printing, the explosives industry as waterproofing agent mixed with ammonium nitrate and nitroglycerin, the fire retardant industry as thickener, and the nano-material related industries e.g. to produce silver or gold nanoparticles, or to develop innovative medicine delivery mechanisms for drugs in pharmaceutical industry.
Facts Worth Knowing
Ultrasonic tissue homogenizers are often referred to as probe sonicator/ sonificator, sonic lyser, ultrasound disruptor, ultrasonic grinder, sono-ruptor, sonifier, sonic dismembrator, cell disrupter, ultrasonic disperser, emulsifier or dissolver. The different terms result from the various applications that can be fulfilled by sonication.