BRABENDER MIXER

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] ... 

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. 

Poly(ethylene)/ZCHS nanocomposites were prepared via melt blending using established methods (7). Poly(ethylene) nanocomposites were prepared by mixing x g of the additive with (100- x g) of pristine poly(ethylene) to achieve x % mass fractions. Melt blending was then performed on a Brabender mixer for 10 minutes at a temperature of about 130°C and speed of 60 rpm. The prepared nanocomposites are identified as PE/ZCHS-5 and PE/ZCHS-10 for 5% and 10% loadings respectively. A reference sample of pure poly(ethylene) was prepared by following the same procedure in the absence of additive. 

Figure 9.14 Transmission electron micrograph of a section of bicontinuous phase formed by 53 wt% polystyrene and 47 wt% polymethylmethacrylate blended with a Brabender mixer at a rate of 20 rpm, which is roughly equivalent to 90 sec, at 200°C. At this shear rate, the two components have about the same viscosity, around 1000 Pa s. The characteristic domain width is around 1 /xm. (From Miles and Zurek 1988, reprinted with permission from the Society of Plastics Engineers.)...

Recycled EVA/GRT powder blends of three particle sizes of greater than 200 turn, 200-500 turn, and greater than 500 p,m with concentrations up to 70 wt.% were prepared by using a Brabender mixer (Mujal-Rosas et al., 2011). The stress-strain behavior showed that upon the addition of smaller particles to the matrix up to 10%, the Young s modulus of the blends increased, while other mechanical properties reduced. At the higher concentration of GRT, all mechanical properties decreased. However, conductivity, permittivity, and dielectric loss factor of blends increased with the powder concentration. 

EHelectric constants and conductivities of PP and PP/MWCNT nanocomposites prepared using a Brabender mixer. (Reprinted from Tjong, S.C. et al, Scr. Mater., 57,461,2007.)... 

Kanomata et al. (2011) prepared compatibilized blends of PA-6 and polyethersulfraie using PES having hydroxyphenyl end-groups. Blends prepared in a Brabender mixer were characterized using TEM and torque iheometiy in comparison with control blends. 

PA-6/UHMWPE/ HDPE-g-MA Brabender mixer/mechanical and tribological properties/FTIR Wang et al. 2007b... 

PA-6/LDPE/PE-g-MA Brabender mixer/SEM/DSC/selective solvent extraction/comparison of blend properties to those of blends with EAA in place of PE-g-MA Jiang et al. 2003... 

PA-6 (25-75)/LDPE (75-25)/E-GMA Brabender mixer/SEM/rheology/DSC/ morphology as function of blcmd composition, compatibilizer concentration, and GMA content/ also used LDPE-g-GMA, SEBS-g-GMA Wei et al. 2005 Minkova et al. 2002... 

PA-66 (3 parts)/PPE (7 parts)/ MA (1 part) Brabender mixer at 250-300 °C/ mechanical properties vs. blend without MA Ueno and Maruyama 1982a... 

PA-6/PPE/PPE-f- phthalimide/SEBS Brabender mixer/traqne rheometry/FTIR/ NMR/mechanical properties/PPE end-capped using N-methyl-4-nitrophthalimide/maximum impact strength at 1.65 % functionalized PPE in blend Ghidonietal. 1996... 

Poly(lactic acid)-g-MA (50)/PVAl (50) Brabender mixer/mechanical properties/NMR/ also blends containing unfunctionalized PLA Quintana et al. 2012... 

Schmukler et al. (1986a, b) prepared compatibilized blends of PVAl with an anhydride-functionalized polyethylene. For example, 50 wt% PVAl was reacted at 325 °C in a Brabender mixer with 50 wt% HOPE grafted with 1.5 wt% methylbicyclo(2.2.1)-hept-5-ene-2,3-dicarboxylic anhydride. Characterization showed evidence for copolymer formation and no gross phase separation. 

Hohlfeld (1986) prepared compatibUized blends of EAA and unfunctionalized PPE by extrusion with st3rene-isopropenyl oxazoline copolymer (S-IPO). In one example, a blend of EAA (30 parts), PPE (35 parts), and S-IPO (35 parts) was mixed in a Brabender mixer at 280 °C. Torque level was higher and mechanical properties were significantly improved compared to blends with PS used in place of S-IPO. See also Xu et al. (1999b) for a study of similar blends. 

PP/ENR/triallyl cyanurate Brabender mixer coupled with an electron accelerator to introduce functional Rooj et al. 2011... 

EMA-co-GMA/SMA Brabender mixer or TSE/mechanical properties/rheology/morphology/comparison to blend with unfimctionalized EMA Bayamet al. 2001... 

ERA (30-50)/PS-co-butyl acrylate-co-(t-butylperoxy methacryloyloxyethyl carbonate) (70-50) Brabender mixer at 180 °C/selective solvent extraction/effect of temperature on grafting efficiency/also blends of peroxide-containing polymer with PP Moriya et al. 1988 (see also Moriya et al. 1989)... 

Product development work is usually carried out in a pilot plant. Here one can use a small Banbury or a Brabender mixer for a batch process and a small twin-screw mixer or a co-kneader for development work on a continuous process. 

This p(ET/HBA) TLCP was mixed with bisphenol-A PC [Sinvet 251, Enimont America, Inc.] in 50 50% wt., blended at 300 C for 30 mins, at 40 r.p.m. in a 30 ml Brabender mixer. Additional 50 50% PC p(ET/HBA) blends with a catalyst, tetrabutylorthotitanate (TBOT) in the amounts of 0.15% and 0.30% wt., were produced under the same conditions. Pure components were processed at the same conditions to determine if processing changed their initial physical properties. All materials were vacuum dried at a minimum temperature of lOO C for 24 hours before processing. 

In our work we used new modifiers in order to improve polymer-fiUer interactions. The modification process was carried out in Brabender mixer. During this process the coupling agent was grafted on the polymer macromolecule and then the reaction with chemical groups on the carbon black surface took place [5]. 

Modified polycaprolactorre was synthesized by melt reaetion of PCL and reactive monomers such as gfycidyl methacrylate (GMA) and maleic anhydride (MAH) in the presence of benzoyl perioxide in a Brabender mixer [138]. Reactive blends of the PCL-g-GMA and the gelatinized starch with gfycerin were prepared and their meehanieal properties and biodegradabilities... 

Melt mixing has been also used to disperse conductive polymers in SBS rubber. Polyaniline doped with dodecylbenzenosulfonic acid was mixed with SBS rubber in a Brabender mixer [119]. A conductivity of 2 S cm was achieved with a loading of 50% of the conductive polymer. According to the authors, this blend could be extruded. However, no supplementary data supporting this conclusion were provided. 

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