Laboratory mixer

Applications for mixers in blending operations vary from small laboratory mixers to large petroleum tanks of several million gallons. Three common mixing operations are ... 

The specimen was prepared by the following method. After mixing HAF carbon black (50 phr) with natural rubber (NR) in a laboratory mixer, carbon gel was extracted from unvulcanized mixture as an insoluble material for toluene for 48 h at room temperamre and dried in a vacuum oven for 24 h at 70°C. We made the specimen as a thin sheet of the carbon gel (including carbon black) by pressing the extracted carbon gel at 90°C. The cured specimen was given by adding sulfur (1.5 phr) to the unvulcanized mixture and vulcanized for 30 min at 145°C. The dynamic viscoelastic measurement was performed with Rheometer under the condition of 0.1% strain and 15 Hz over temperatures. 

Heavy Duty Laboratory Mixer Emulsifier, Model L4RT-A, Silverson Machines Ltd., Waterside Chesham, Bucks., England, HP5 1PQ. 

Compact laboratory mixer used for stirring small sample volumes in containers (i.e., test tubes, centrifuge tubes, colorimetric tubes, small flasks). Volume 1(1,3). 

Sulfur Dispersion by Laboratory Mixer. The influence of the following variables on the dispersion of sulfur in asphalt was assessed in the laboratory. The mixes were prepared using 85-100 pen grade asphalt with all of the mix ingredients preheated to 140°-150°C. 

These particles require no activation, but can be made super-fine by stirring a 10% suspension in 0.1 M NaHCOs, pH 8.5-9, with a high-speed mixer (e.g., Silverson Laboratory Mixer-Emulsifier). 

Conduct tests at several, perhaps 5, flow rates through the laboratory mixer. 

Select a flow rate for the laboratory mixer that gives acceptable yield. 

Residence time = 0.0437 icc (same as the laboratory mixer reactor). 

When new drugs and drug-delivery systems are developed in the laboratory, the correlation of the necessary production equipment may be very difficult indeed. For example, the shear needed to create the desired particle size of an emulsion with the help of laboratory equipment may pose serious problems in the selection of plant equipment necessary to reproduce the attributes of the product. Recording the speed of a laboratory mixer is not sufficient by itself for this task definition of the operating principle and equipment design is necessary to accomplish the task. 

In testing an equation which he gives for calculating the theoretical variance of samples taken from a randomly mixed batch of two materials, P and Q, Stange uses data for a laboratory mixer which he refers to as "an older model of the Werner Pfleiderer firm, Stuttgart. This is a sigma-blade mixer, which ordinarily is used for sticky materials rather... 

Several basic designs of the internal batch-type mixers are available. The most popular are the laboratory mixers manufactured by, e.g., Brabender or Haake, and their homologues on the larger scale manufactured by, e.g., Banbury or Moriyama dispersion mixers. 

Polymer-stabilizer mixtures were homogenized in the W 50 EH chamber of a Brabender Plasti-Corder laboratory mixer at 190 °C and 60 rpm for 10 min. After removing the material from the chamber, 6 mm thick plaques 8 x 8 cm were molded in a laboratory hot press at 200 °C for 2 min under 50 kN for deairation plus another 2 min nnder 100 kN followed by water cooling to 70 °C for ca. 15 min under 150 kN. 

Compositions were prepared by blending CN with melted polymer in a laboratory mixer Brabender at 190°C. TOPANOL (l,l,3-tris(2-methyl-4-hydroxy-5-t-butylphe-nyl)butane) and dilamylthiodipropionate (DLTP) were added in the amount of 0.3 wt% and 0.5 wt% as antioxidants to prevent thermal-oxidative degradation during polymer processing. 

PP-g-GMA (1 part)/PPE-g-MA (1 part) Laboratory mixer at 270 °C/mechanical properties vs. blends with unfunctionalized polymers/PP grafted in separate extrusion with 10 wt% styrene and 3 wt% GMA/also used p-phcmylcaiediamine as coupling agent Togo et al. 1988... 

Following the trend of using PVC as matrix, research on the use of EFB as composite in PVC matrix was also reported. Bakar et at [37] used the EFB as filler in unplasticized poly(vinyl chloride) (PVC-U). They studied the effects of extracted EFB on the processability, impact and flexural properties of EFB/PVC-U composites. PVC-U resin, EFB and other additives were first dry-blended using a heavy-duty laboratory mixer and then milled into sheets on a two-roll mill before being hot-pressed and cut into impact and flexural test specimens. There were two kinds of EFB used in this experiment, which were extracted and xmextracted. The FTIR showed that the unextracted EFB contained oil residue, while the extracted one contained less oil residue. The results showed that both extracted and unextracted EFB decreased the fusion time and melt viscosity. However, the fusion time increased with the increase of extracted EFB content. Meanwhile, there was no significant difference in both the impact and flexural properties of extracted and xmextracted EFB. 

Under the conditions of this experiment [308], the minimum suspension concentration, corresponding to the maximum adhesion, is reached at a speed of 5 rev/sec for the laboratory mixer. 

Blender n. A round, softish brush of badger hair or similar material with a blunt tip, used for blending colors and removing brush marks left by coarser brushes. (2) A small laboratory mixer used to dispense pigment in a vehicle. 

Jamrack, W. D., Logsdail, D. H., and Short, G. D. C. Laboratory mixer-settlers. Progress in Nuclear Energy, Ser. Ill, vol. 2, Process Chemistry. Pergamon Press. 

A laboratory mixer (Haake Buchler) with two nonintermeshing counter-rotating rotors and an electrical heater in the barrel wall was used. A specially designed front piece with a glass was attached to measure the circulation time, shown schematically in Figure 1 [22-26]. 

The objects of study were selected mixture of low-density polyethylene (LDPE) with wood flour (WF), natural rubber (NR) and ethylene-propylene rubber (EPDM). WF content is 40 wt.%. Rubber injected at 10 and 20 masses %. As composite materials based on LDPE blending performed on a laboratory mixer at a temperature of 140°C for 5 minutes and then get the film samples in a laboratory press. The sample thickness was 100 10 microns. 

The blend preparation was produced by mechanical mixing of PP and LDPE in a laboratory mixer at a temperature of lOO C for 5 minutes in the nitrogen atmosphere to prevent oxidation of LDPE. Isotropic films were fabricated by pressing with cellophane substrate at a temperature of 190°C and pressure of 7.8 MPa, followed by quenching in water (25°C). The thickness of the PP/LDPE films was 130 10 pm. 

In the first studies on MFCs, the composites were prepared on a laboratory scale performing every one of the three aforementioned processing stages separately, one after another. Blending was done in a laboratory mixer or a single-screw extruder to obtain non-oriented strands that were cold-drawn afterward in a machine for tensile testing, followed by annealing of the oriented strands with fixed ends [14,15,58-60]. 

Processing conditions or chemical reactions occurring in one or both phases of the blend can strongly affect the phase inversion. Of course, these two parameters have a direct effect on the viscosity ratio of the components. The same blend of polyamide/styrene-acrylonitrile copolymer developed phase morphology where PA6 is the matrix when processed using a single-screw extruder, whereas the inverse situahon occurred when the blend was mixed several times in a laboratory mixer. 

Studied mixes containing boron oxide and other mineral fillers (Table 8.1) were prepared with a Brabender-Plasticorder laboratory mixer (Germany), whose rotors were operating with 20 rpm during components... 

Components were mixed in a ratio determined by the specification of the planned experiment (Table 1) in a 0.2-dm laboratory mixer Werner-Pfleiderer. At first, epoxide and liquid rubber were mixed together. Then a catalyst and buffing dust were added, and after further mixing, diisocyanate... 

Rubber chemists often note that the compound made under laboratory conditions differs from a batch made as normal factory production. Whilst laboratory mixers do, as a general rule, impart more mixing per unit volume than a production-size mixer, the laboratory mixer giving more intensive mixing for the same temperature rise, it is also very likely that the chemicals are far more accurately weighed under laboratory conditions. 

It is often not practical to use actual process fluids in the mixing laboratory, as this can involve the use of expensive and obstructive safety precautions as well as inconvenient temperatures and pressures. To avoid these problems, suitable simulant fluids must be found that will behave in a manner representative of the process fluid in the laboratory mixer. It should be noted that the simulant fluid must have the correct rheological properties for the scale at which the measurements are to be made. This is not necessarily the same as simply having the same properties as the fluid in the process for example, if it is non-Newtonian. 

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