Sigma Mixer

Film Formation. Starch-g-PAN samples used for this study were prepared as described above, except that the small amounts of PAN homopolymer were not removed by DMF extraction. For the graft polymerization with gelatinized starch, the starch-water slurry was heated for 30 min at 85°C before reaction at room temperature with acrylonitrile and ceric ammonium nitrate. Saponifications in these experiments were carried out by stirring. 55 g of graft copolymer with 450 ml of 0.711 sodium hydroxide solution in a sigma mixer for 2 hr at 90-100°C. 

Adhesives, prepared in the Sigma mixer, are tested for their viscosity and homogeneity before application onto the surface of the vessel to be lined. It is usual to give a first and primer coat of the adhesive over the blasted surface immediately after sand blasting. 

Oil or electric heated 650 ml sigma mixer is used in this method. Temperature of mixer jacket is adjusted to 88°C. Standard formulation is used for this test, containing PVC - 225 g, Burgess No. 30 clay - 40 g, and diisodecyl phthalate - 124 g. Time is measured from the moment of plasticizer addition to the diy point which is easy to determine from a sudden drop of torque. 

Used in the manufacture of hot-melt pressure sensitive adhesives using single or twin-screw extruders. Can also be used with sigma mixers to achieve a more uniform dispersion of antioxidants. 

Fig. 38. Various mixer types for viscous pastes (a) the change-can mixer, (b) rake mixer, (c) double-rake mixer, and (d) sigma-blade kneader.

Screw-Discharge Batch Mixers A variant of the sigma-blade mixer is now available with an extrusion-discharge screw located in the saddle section. During the mixing cycle the screw moves the material within the reach of the mixing olades, thereby accelerating the... 

Kneadermaster This mixer (Patterson Industries, Inc,) is an adaptation of a sigma-blade mixer for continuous operation. Each two... 

Since paste mixing is not within the scope of this section, such widely used paste mixers as the sigma blade and banbury types will not be covered here but instead are discussed in Sec. IS. 

Kneaders, Z- and sigma-blade, and Banbury mixers as shown in Figure 7.20, are generally used for the mixing of high-viscosity liquids, pastes, rubbers, doughs, and so on. The tanks are usually mounted horizontally and two impellers are often used. The impellers... 

Hah, K. R. and Godfrey, J. C. Trans. Inst. Chem. Eng. 46 (1968) 205. The mixing rales of highly viscous Newtonian and non-Newtonian fluids in a laboratory sigma blade mixer. 

Sigma-blade mixer, in bar soap manufacture, 22 751 Signaling smokes, 5 827, 830 Signal processing in the element (SPRITE), 29 162-163... 

Sapanification. S xxiifications were carried out in a Readco steam-jaoiketed sigma double-arm mixer with 1 quart working Cc city (Teledyne Raadoo, York, PA). There were holes in the lid to accommodate a reflux condenser and to permit addition of reagents. 

Mixing of the crystalline ingredients of oxidant, fuel elastomer binder (butadiene-2-methyl-5 vinyl-pyridine copolymer plasticized with the formal of diethylene glycol monobutyl ether) 26% by vol is done in a sigma blade mixer. The completed mix is blocked in a hydraulic press to form a chge suitable for extrusion. The extruded strand is cut into grain blanks which are cured at... 

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