Haake ‘Rheocord

We carried out experiments to define the optimal conditions in a reactive extrusion process, and to obtain maleic anhydride grafted polymers of polypropylene copolymers (3050 MN 4 supplied by ATOCHEM). The previous studies were carried out in a batch mixer (HAAKE RHEOCORD), at a temperature of 220° C and a mixing speed of 64 rpm, during 20 minutes. Three different systems were tested i. with pure maleic anhydride ii. in the presence of a solvent (toluene or chorobenzene) iii. by introduction... 

The next example is of a Pre-Startup Review or a Process Hazards Audit held on a piece of purchased processing equipment, a Haake Rheocord Torque Rheometer and Laboratory Twin-screw Extruder. The organization responsible for this extruder has a standard checklist of eleven pages of items to be considered by the technical person or persons in charge of the equipment or process, before the review is held. Copies of the completed checklist are then sent to each committee member before the meeting for review. Generally, in a review of this type, the group will convene at the location of the equipment rather than in a conference room to go over the material provided. In this case, the committee consisted of ... 

Puaux et al. [117] studied the bulk polymerization process of L-lactide initiated by stannous octoate in a laboratory batch reactor. They conducted the polymerization reactions in a Haake Rheocord internal mixer with a R600 chamber. Their set-up... 

The Haake rheocord is an alternate procedure used to prepare TPEs. The component polymers are mixed thoroughly and then the curatives, if any, are added. Peroxides are added just before damping." The material, while hot, is sheeted out on a mixing mill and then granulated. Aju et al. prepared NBR/PP and NR/PP blends by this method." ... 

Mechanical Properties of Native and Chemically-Modified Zein Mechanical strength measurement was performed to evaluate the bulk properties of the tensile bars from both native and chemically-modified zeins. Triediylene glycol (TEG) is an excellent plasticizer (12) for zein. Native and chemically modified zeins were each blended with either 10 or 1S% TEG in a Haake Rheocord 90 torque rheometer equipped with high shear roller blades to yield a taffy like matrix. The rheometer was stopped when the torque dropped and became constant. 

Mechanical Properties were measured with Haake Rheocord 90 equipped with high sheer roller blades Carver Press, Model C with ASTM D 638 type V bar Instron Model 4201. 

Preparation of Tensile Bars by Compression Molding As stated in Discussion of Result section blends of TEG with either native or chemically modified zein were prepared with a Haake Rheocord 90 torque rheometer. The taffy like matrix were zen with liquid nitrogen and ground in a Wiley mill. The powder was molded into tensile bars with a Carver Press, Model C at... 

Haake Rheocord EU 10-V unit. In this procedure 80 g filler was preblended with the necessary amount of surfactant, then it was introduced into the mixer at various temperatures and was homogenized at 100 rpm for 10 min. Since the compounds used in the project melt over a wide range, the temperature of the coating was selected to be 30 °C higher than the melting temperature of the surfactant in order to create similar conditions in all cases. 

Figure 1 The effect of processing aid on the fusion of rigid PVC compound (Haake Rheocord bowl torque versus temperature, heating at 4°C/min).

Swelltest die heads also allow contactless estimation of die-swell to be obtained. A Planetarimixing head also allows the study of powdery materials (again useful in PVC processing). Temperatures up to 300°C can be studied. Current equipment of this type is produced by Brabender ( Plasticorder ), Haake ( Rheocord ) and Hampden Instruments (variable torque rheometer). 

These capillary rheometers are principally the same as those described in Sections 3.2.1 and 3.2.2 except for the melt transport system which is of the screw extrusion type rather than the plunger type discussed earlier. A schematic diagram of an extrusion capillary rheometer is shown in Fig. 3.5. Commercially available extrusion capillary rheometers are the Haake Rheocord (Haake Buchler Instruments, Inc., Saddle Brook, NJ) and the Brabender Plasticorder (Brabender, Duisburg, Germany). The rheological property measurements can be done using a circular or slit orifice, as these are separate attachments for the miniaturized single screw extruder. 

CRPP sample production was carried out in a Haake Rheocord 90 unit equipped with a Rheomix 3000 batch mixer. Experiments were carried out at various temperatures (230, 250, 270 and 290 C) and NOR free radical generator concentrations (0, 0.75%, 1.5% and 3%). Expoiments using the paoxide initiator were carried out only at one concentration of 250 ppm. At each set of conditions, samples wo-e collected at a preset run time of 5 minutes. All experiments were carried out at 100 rpm. 

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