Other Additives
Tek-Mix™ technology has been demonstrated to provide profound benefits to mixes and blends containing a wide range of additives. Some additives are used in powder form, others as liquids, and still others as particles. Below is a partial list of additives which could benefit from the Tek-Mix™ mixer:
- Antimicrobials
- Antistatics
- Flame retardants
- Fillers
- Lubricants
- Nucleating agents
- Stabilizers
- Plasticizers
- Talcs
- Nanoclays
- Pigments
- Nanotubes
- Thermally sensitive additives
Thanks to low average shear rates and excellent heat transfer resulting from a thin melt layer in contact with “pocketed” metallic surfaces, the processing temperatures can be kept very low. Due to the shape of the barrel and rotor, the melt is kept in a constant stretched condition and simultaneously subjected to a series of highly transient shear and extensional deformations due to flow in and between the uniquely shaped pockets (to read more on extensional flow technology, click here).
The low temperatures in the Tek Mix ™ mixer permit the addition of thermally sensitive additives (liquid and solid), creation of blends using thermally sensitive resins, and processing of other sensitive materials. Organic pigments and additives, which are often less thermally stable than inorganic pigments, can often be used when mixed using Tek Mix™ technology. Liquids can be injected and immediately dispersed without volatile flashing. Typical processing temperatures of several resins are listed below, compared with the actual temperature achieved in the Tek-Mix™ treatment. Temperatures were measured by direct immersion of the probe into the melt stream at the die exit. Many of the Tek-Mix™ temperatures approach the melting point for crystalline polymers, or the glass transition temperature for amorphous polymers.
These Tek-Mix™ processing temperatures allow improvements in Reactive Extrusion ("REX") per the following points:
Reactive Extrusion (REX) – REX is used for monomer grafting, dynamic reactive mixing of polymer blends, and customizing molecular weights These tasks normally fall in the domain of twin screw technology. However, Stratek’s Tek-Mix™ mixer some important advantages:
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a.
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Adjustable residence time, 15 to 400 seconds
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b.
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Temperature control ±½°C
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c.
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Process temperatures ranging from crystallization or glass transition temperature to 350 °C
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d.
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Tight control of reaction pressure, 200 to 2,500 psi
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e.
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Improved dispersion of reactants, leading to improved reaction yield
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f.
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Improved cooling:
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- The Tek-Mix™ mixer uses water-saturated cool air, which reduces thermal gradients and stabilizes the process. By reducing viscosity in the treater, yet maintaining a cool environment, reactant volatility is reduced and mass transfer into the melt is improved.
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Tek-MixTM - Extensional / Elongational Flow
The Next Step in Mixing & Blending
The Next Step in Mixing & Blending
