Internal mixer mechanism

PA-6/HDPE/EPDM-g-MA Internal mixer/mechanical properties/ morphology/DSC/rheology Dou et al. 2013... 

PETG/EVAc-g-MA Internal mixer/mechanical properties/Young s modulus/gel content/effect of MA and DCP RI level on EVAc properties Hwang et al. 2012... 

Elastomer-plastic blends without vulcanization were prepared either in a two roll mill or Banbury mixer. Depending on the nature of plastic and rubber the mixing temperature was changed. Usually the plastic was fed into the two roll mill or an internal mixer after preheating the mixer to a temperature above the melting temperature of the plastic phase. The plastic phase was then added and the required melt viscosity was attained by applying a mechanical shear. The rubber phase was then added and the mixture was then melt mixed for an additional 1 to 3 min when other rubber additives, such as filler, activator, and lubricants or softeners, were added. Mixing was then carried out with controlled shear rate... 

The devolatilization of a component in an internal mixer can be described by a model based on the penetration theory [27,28]. The main characteristic of this model is the separation of the bulk of material into two parts A layer periodically wiped onto the wall of the mixing chamber, and a pool of material rotating in front of the rotor flights, as shown in Figure 29.15. This flow pattern results in a constant exposure time of the interface between the material and the vapor phase in the void space of the internal mixer. Devolatilization occurs according to two different mechanisms Molecular diffusion between the fluid elements in the surface layer of the wall film and the pool, and mass transport between the rubber phase and the vapor phase due to evaporation of the volatile component. As the diffusion rate of a liquid or a gas in a polymeric matrix is rather low, the main contribution to devolatilization is based on the mass transport between the surface layer of the polymeric material and the vapor phase. 

Of all the methods for the production of block and graft polymers, the greatest importance, from the view of commercial simplicity, involves mechanical synthesis. The block and graft reactions can be potentially performed directly during polymer processing and in standard equipments, such as internal mixers, injection molding machines, and extruders. 

Mixing Mechanisms Consider a calendering process for manufacturing PVC floor covering. The line consists of a ribbon-type blender in which the PVC is dry-blended, and an internal mixer that feeds a SSE equipped with a static mixer, feeding the first nip of the calender. What types of mixing mechanisms does the polymer experience Specify the locations at which each mechanism occurs. 

Mechanical Mixing of PFAP(II) Compounds. PFAP(II) O-ring seal formulations were mixed in a Brabender internal mixer equipped with a mixer head of 85-mL volume and cam-type blades. The mix order was as follows (1) PFAP(II), (2) silica (Quso WR82, silane-treated surface) (3) magnesium oxide and (4) bis(8-oxyquinolate)zinc(II). This compound then was placed on a small two-roll rubber mill (2 in. X 6 in.) and dicumyl peroxide was mixed in at 57°C. 

BR rubbers or high styrene ESBR rubber. Usually, these rubbers are not compatible [9]. Figure 1.5 shows, for example, the DSC thermograms of SSBR/BR (75/25) samples mechanically blended in an internal mixer at 50°C and solution (cyclo-hexane) blended. The Tg-value of the BR phase (-110°C) is unaffected however, the glass-rubber transition of the SSBR phase is influenced on the low temperature side. The two transition effects clearly present are an indication for the non-compatibility of these two polymers. 

SEM / selective solvent extraction / FTIR / DMTA / WAXS thermal redistribution in internal mixer at 260°C / NMR / TLC / DSC internal mixer at 240°C / torque rheometry / SEM / GPC / mechanical properties / effects of mixing time / effects of PA amine and acid end-group concentrations internal mixer at 240°C / selective solvent extraction /... 

Mascia and Hashim [1997] have prepared compatibilized blends of PA with PVDF by using car-boxyhc acid-functionalized PVDF. In an example 20 parts PA-6 was combined with 80 parts PVDF-g-MAA (10% MAA) in an internal mixer at 240°C. The graft copolymer-containing blend was characterized by SEM, FTIR, mechanical properties, selective solvent extraction, and rheology. The effects of adding zinc acetate were studied. 

PA-6 (100-75) / EDPE (0-25) / LDPE-g-BA (18% BA) (0-2.4) internal mixer coupled to SSE at 260°C / SEM / torque rheometry / mechanical properties / water absorption / hardness / effect of premixing EDPE + EDPE-g-BA Raval etal., 1991... 

PA-6 (90) / EMAA (10) internal mixer at 250°C / mechanical properties and morphology as function of MAA content / ETIR / selective solvent extraction / DSC / role of H-bonding MacKnight et al., 1985... 

PA-6 (85) / PP (7.5-15) / PP-g-AA (6% AA) (0-7.5) internal mixer or TSE at 235-255°C / selective solvent extraction / morphology /mechanical and viscosity properties / reaction kinetics from torque measurements Dagli etal., 1994... 

PA-6 (95-60) / SMA (5-40) internal mixer at 250°C / mechanical properties / SEM / WAXS / SAXS / blends with SMA pre-reacted with 0-100% octadecylamine based on MA content Kelnar et al., 1997... 

DSC / SEM / mechanical properties / selective solvent extraction / ETIR internal mixer at 240°C / torque rheometry /... 

FTIR / DSC / DMTA / mechanical properties internal mixer at 200-250°C torque vs. time, temperature / DSC / DMA / improved modulus and tensile strength as copolymer forms internal mixer at 230, 250, or 270°C / torque rheometry / DSC / mechanical and thermal properties SSE at 265-270°C / thermal redistribution during molding at 270-320°C / DMA... 

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