Brabender mixing

Table II. Torque-Generation Data Obtained During Brabender Mixing of Resins IV and V ...

The significant improvement in flow properties of resin IV vs. V is evident from the data. First, the torque from Brabender mixing indicates that resin IV is an easier-flowing material (Table II). The lower torque values for IV indicate the necessity of a lower-energy input to mix the polymer melt. This lower rotational force therefore indicates the polymer melt has a lower melt viscosity. Secondly, injection-molding conditions demonstrate the improved processability of resin IV (Table III) in comparison with resin V. At the same injection cylinder temperatures, the injection pressure for the tensile bar and Izod/heat distortion bar molds is lowered by 300 psi and 250 psi, respectively. 

The best glass reinforcement for both the Brabender mixed polystyrene and the Brabender mixed and injection molding compounded polypropylene was a high integrity strand with 408 hlaments of a 10-/tm diameter, 1/4 in. or 1/8 in. long ... 

Properties of Brabender Mixed Polystyrene/Glass Composites 25%... 

All compounds were melt-blended in a Brabender mixing chamber. It is evident from the results in Table 7.4 that all the filled polymers had improved flame retardant properties. For EVA and EVA-based nanocomposites containing 2.5 phr of filler, the PHRR decreased as follows EVA > organoclays purified MWCNTs. For EVA and EVA-based composites containing 5.0 phr of filler, the PHRR decreased as follows EVA > organoclays > purified MWCNTs = crude MWCNTs. Crude MWCNTs were as effective in the rednction of PHRR as purified MWCNTs Increasing the filler content from 2.5 phr to 5.0 phr caused an additional flame retardant effect that was most significant when purified or crude MWCNTs were used. 

Compounds of SWCNTs and MWCNTs in LDPE BPD 8063 were melt blended in a Brabender mixing chamber according to the formulations indicated in Tables 7.5 and 7.6. The corresponding cone calorimeter measurements are shown... 

Solid residue was obtained by two processes to reduce discarded tires pyrolysis and thermal shock. Techniques such as X-ray, FTIR, TGA and SEM were used to characterize the samples. Two types of polyethylenetherephtalate, PET (virgin and recycled) were analysed physicochemical and mechanically to be used as matrix. A composite material was manufactured by employing a Brabender mixing chamber in order to nse the grannies as fdler on PET at different concentrations. The mixed material was laminated and tension test were undertaken in samples to acquire the mechanical properties. Studies of ffactography were performed to understand the failure mechanics. 

In preliminary tests, melt mixed blends of PP and LCP were processed at six different temperatures (Tcyi 230, 240, 250, 260, 270, and 280°C) with a Brabender Plasti-Corder PLE 651 laboratory single-screw extruder. The measured melt temperatures were about 10°C higher than the cylinder temperatures (Tcyi). The objective was to study the influence of temperature on the size and shape of the dispersed LCP phase. Two different polypropylenes were used to ascertain the effect of the viscosity of the matrix on the final morphology. Different draw ratios were obtained by varying the speed of the take-up machine. 

DSC revealed that the XG and starch did not interact synergistically and hence did not promote the formation of three-dimensional network structures. However, the hydrocolloid significantly decreased the retrogradation and syneresis of the starch paste, particularly in blends with a starch/XG ratio of 8.5/1.5. Mixing 1% or 2% tamarind XG with 9% cornstarch resulted in an increase in the paste viscosity from 385 to 460 and 560 BU (Brabender units), respectively [298]. The XG is associated with starch, as was evident from the lowering of the pasting temperature and the synergistic increase in pseudoplasticity and yield value of the blend pastes. However, carboxymethylated and hydroxypropylated XGs showed a diminished interaction. 

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). 

For the compatible elastomer-thermoplastic blends, melting of the two polymers is the first step followed by subsequent vulcanization of the elastomeric phase. A typical mixing cycle for dynamically vulcanized NR-PE blend (DVNR) in a Brabender mixer is as follows [58] ... 

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... 

Melt-mix Brabender high-intensity flux mixer 63,800 900 4.3 0.1... 

The researches of ZnCFO compatibility with the matrix of isoprene rubber in plasticorder "Brabender" PLE 6511 have shown, that the disperse process of composite is accompanied by lower power consumption and its best compatibility in comparison with zinc oxide (fig. 4). The absence of ZnCFO particles as extraneous impurities in rubber mix also was visually observed, while the zinc oxide particles were well appreciable [7],... 

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... 

Studies on the kinetics of carbon black dispersion in various rubbers have been reported using a Brabender mixer fitted with cam-type rotors [110]. Dispersion rating, determined by visual inspection of photomicrographs, was found to depend strongly on mixing time. For an SBR emulsion, it was observed that there was an initial delay period where the carbon black agglomerates were thought to be fractured and incorporated into the rubber. Subsequently, the process of dispersion continued for a considerable time thereafter. 

For gel processing, the components, UHMWPE, optionally filler, processing oil, and lubricant are mixed. The components are preferably mixed in a continuous fashion, e.g., in a twin-screw extruder or a Brabender extruder, or a screw extruder with a blown film die. After mixing, the mixture is shaped. Shaping will depend upon the... 

The apparatus used for the first tests included a 3/4-inch diameter, 20 1 L/D laboratory extruder. The second series of evaluations was run on a Brabender torque rheometer equipped with mixing head. The third tests utilized large scale processing equipment including a two-roll,... 

Brabender Processing. In another series of tests, two commercial (stabilized) resins, unstabilized polypropylene, and the latter with 0.4% DLTDP + 0.1% PPP were masticated for five minutes at 50 r.p.m. and 180 °C. in the Brabender apparatus, then mixed for 25 minutes at 150 r.p.m. and 200°-215°C. Meter-gram torque readings were plotted over the mixing cycle along with temperature, and intrinsic viscosity was measured for each formulation before and after processing. 

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