Brabender ‘Plasticorder

De Sarkar et al. [52] have reported a series of new TPEs from the blends of hydrogenated SBR and PE. These binary blends are prepared by melt mixing of the components in an internal mixer, such as Brabender Plasticorder. The tensile strength, elongation at break, modulus, set, and hysteresis loss of such TPEs are comparable to conventional rubbers and are excellent. At intermediate blend ratio, the set values show similarity to those typical of TPEs (Table 5.5). 

Initially, the co-agents were mixed with PVDF and FMVQ separately and the mixtures were subjected to mild irradiation. Solubility tests indicated no cross-hnking during this operation. The polymeric components were then mixed in the presence of CaO/MgO in a Brabender plasticorder at a rotor speed of 60 rpm at 160°C. Subsequently, the temperature was lowered to 130°C and a 0.2% benzoyl peroxide paste was added. Mixing was continued for 10 more minutes. Cure characteristics... 

Akhtar has studied the morphology and physical properties of NR and high-density polyethylene blends prepared in Brabender plasticorder at 150°C at a rotor speed of 60 rpm [53]. Films were molded between two chromium plates at a pressure of 0.34 MPa. The films along with mold were... 

The effect of the components and conditions of preparation on the properties of a 70/30 LDPE/clay composite is shown in Table I. The 10/90 mixture of LDEE Bakelite Polyethylene Resin DYNH-1 (Union Carbide Corp.) and Hydrite 10 clay (Georgia Kaolin Co.) was compounded at 150 C in the Brabender Plasticorder in the presence of MAH and/or t-butyl perbenzoate (tBPB). The EE-coated clay was then mixed with additional DYNH-1 LDPE at 130°C to yield a 70/30 PE/clay composite. A 30 70 PE/clay concentrate was prepared in a similar manner at 150 C and converted to a 70/30 EE/ clay composite at 130 C. The 10/90 PE/clay concentrate is an easily handled, clay-like product while the 30/70 concentrate is... 

Plastics. The plastic films used in this study were prepared by the Otey semi-dry method (3), and were formulated to contain (dry weight basis) 40% starch, 45% poly(ethylcne-co-acrylie acid) (EAA), 15% urea (starch/EAA plastic) or 40% starch, 25% EAA, 25% low density polyethylene (PE), 10% urea (starch/PE/EAA plastic). Films were blown with a Brabender Plasticorder extruder as described in detail elsewhere (3). 

Treatment of PVC, suspended in chlorobenzene, with Et2AlCl followed by the addition of methanol greatly improved the thermal stability (6). This will be the subject of a separate publication. However, the nature of the improvement was different—i.e., film pressed in air at 200°C was yellow not colorless, but processing stability as determined by the torque rheometer test in the Brabender Plasticorder at 195°C was far superior and was measured in hours rather than minutes. The removal of labile chlorine atoms by Et2AlCl undoubtedly contributed to heat resistance. However, in the absence of a further reaction, such dehalo-genation probably became dehydrohalogenation, contributing to color development. 

High Density Polyethylene - [Both regular and high molecular weight (HMW)]. The time to increase in torque at 220°C. by the Brabender Plasticorder was determined as a measure of crosslinking. Yellowness Index after the Brabender test at 220°C. and after the first extrusion at 260°C. were also performed. 

Employing the Brabender plasticorder at 220°C, 50 R.P.M. with the ram open compounds 1, 2, 3 and prevent crosslinking about three times longer than BHT and AO-1 alone. 

Materials. Two types of standard tire cord obtained from Gen Corporation were used in this investigation polyester, 1300/3, and nylon 66, 1260/3. The rubber composition to which the adhesively dipped cords were bonded had the following composition in parts by weight styrene-butadiene rubber (SBR) 1502, 100 N330 carbon black, 50 zinc oxide, 5 stearic acid, 0.5 sulfur, 1.7 2-morpholinothio-benzothiazole, 2. Master batches were mixed 7 min in a 350-ml Brabender Plasticorder, and curatives were added on a cool two-roll mill. Cure characteristics at 155 °C were determined with an oscillating disc rheometer (ASTM D 2084). The time to reach 90% of the final cure state was 23 min, and the Shore A hardness of the final vulcanizate was approximately 60. 

The use of the Brabender Plasticorder is widespread in the development and quality control of formulations destined to be used in uPVC foam extrusion applications. The morphology transformations associated with the process have been widely studied but the particularities of the application have not often been taken into account - low K-value and high concentration of high molecular weight process aid. This work uses a commercially viable formulation to examine the fusion aspect of the transformation process. Differential scanning calorimetry is used to observe the degree of fusion. 9 refs. 

The polypropylene used in these experiments was Hercules Profax 6501. Small batches (48 gram resin) were fluxed at 190°C in the mixing cam heat of a Brabender Plasticorder with 1% minutes addition time for resin and additives and a 3 minute mix at 30 rpm. Mixes were cooled in a room temperature hydraulic press. 20 mil thick plaques (8" x 8"), were pressed at 215°C and 20,000 lbs in a Pasadena hydraulic press. 

Procedure Thirty-eight grams of Lupolene 5260 Z containing 0.05% AO-1 and 0.05% processing stabilizer were mixed in a Brabender Plasticorder 50 operating at a temperature of 220°C, the rotor rotating at a speed of 50 r.p.m. in an air atmosphere. 

The reaction is done in equipment such as a Brabender Plasticorder or extruder it can be a batch or a continuous process. Maleic anhydride is dissolved in styrene at 60°C, and the solution (still at 60°C) is injected into the molten polymer which is being fluxed or mixed at the desired temperature. Since the polymerization and grafting reactions are just about instantaneous, no reaction time is needed after monomer addition is finished. 

When the grafting reaction is done in the Brabender Plasticorder, the polymer is fluxed for two minutes. The monomer mixture is continuously injected into the molten mass over one minute, and the reaction mixture then discharged from the Plasticorder. 

Published information on urethane polymerization detail largely concerns thermoset urethane elastomers systems.4 13 In particular, the work of Macosko et. al. is called to attention. The present paper supplements this literature with information on the full course of linear thermoplastic urethane elastomer formation conducted under random melt polymerization conditions in a slightly modified Brabender PlastiCorder reactor. Viscosity and temperature variations with time were continuously recorded and the effects of several relevant polymerization variables - temperature, composition, catalyst, stabilizer, macroglycol acid number, shortstop - are reported. The paper will also be seen to provide additional insight into the nature and behavior of thermoplastic polyurethane elastomers. 

In the present study we utilized Plasticorder torque values (polymer viscosity) on a relative basis, principally to follow the course of thermoplastic polyurethane elastomer polymerization, and the effect of several relevant variables on this polymerization. These torque data, expressed in meter-grams, served our purposes well, and we have not attempted to translate them to absolute rheological units. Such translation, which is a rather complex problem, has been addressed by others using a different rotor type and other polymers in the Plasticorder.14 That study concluded that the shear rate, y, of the Brabender Plasticorder with a somewhat different rotor configuration (roller blade) is in the range of 23 - 228 sec 1 over the rotor speed range of 30 - 200 rpm. 

In Polymers 14 and 15 the shortstop, 1-propanol, was added to the polymerizing reaction mixture in the Brabender Plasticorder reactor 7 minutes after the polymerization had been started (see asterisk in Figure 9). 

The Brabender Plasticorder is also a useful device for studying the effect of shear and heat on fully formed polymeric materials. And this is another way that we used it in the present study. The technique employed was to bring the Plasticorder mixing chamber to temperature, then add granules of thermoplastic polyurethane elastomer (at 25°C) to the chamber and record the viscosity-time-temperature pattern that developed. ... 

Using new methods (7) for following the transformation of metal soaps in the polymer, this chapter studys the synergism obtained from chloride ions between zinc and calcium stearate in the absence or presence of secondary stabilizers during PVC thermomechanical treatments in the Brabender plasticorder or in a rolling mill. 

To follow the consumption of zinc and calcium carboxylates during heating time in the Brabender plasticorder at 190 °C, the following recipe was used PVC, 30 g dioctylphthalate, 9 g zinc or calcium stearate, 6.6 phr for the synergistic mixture zinc stearate, 3.3 phr and calcium stearate, 3.3 phr. These amounts of stabilizers are about three or four times larger than the quantity used in industrial conditions to facilitate the methods of titration. The plasticorder is stopped occasionally, and from all the samples only one part is placed in solution in tetrahydrofuran for titration of chlorides and stearic acid. 

For zinc and calcium-stearate mixture, there is always an excess of transformed stearate from stearic acid titration with respect to metal chlorides titration during gelation of plasticized PVC in the Brabender plasticorder (area 1-3 on the plastogram, and Curves 1 and 2 on Figure... 

Synergistic Mixture Zinc Stearate and Organo Compounds as Secondary Stabilizers. From the previous results, it is clear that in order to prevent PVC cross-linking and to increase the action time of stabilizer (previously defined with the Brabender plasticorder (1,3,4,6,7)), it is necessary to impede zinc chloride accumulation in the polymer. 

Ternary blends of iPP(Moplen T 30 S, 300,000, Montecatini), PB-1 (PB 8340, 700,000, Shell), and HOCP (Escorez, 630, Esso Chemical) were prepared by melt processing in the 50 ml mixing room of a Brabender Plasticorder PEE 330 mixer at 60 rpm and 195°C for 15 min, dry nitrogen was continuously purged into the mixing chamber. Neat iPP and PB-1 processed under similar conditions were investigated as reference materials. The weight ratio of the blend components are reported in Table 6.10. 

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