Twin screw extrusion reactive

AA Adewole, K Dackson, M Wolkowicz. Adv Polym Technol 13 219-230, 1994. BD Favis, D. Therrien. Processing/Morphology Relationships in Polymer Blends During Twin-Screw Extrusion. 2nd Intern. Congress on Compatibihzer and Reactive Polymer Alloying, Compalloy 90. 1990, p. 59. 

Ammonium Substituents by Reactive Twin-Screw Extrusion Processing, J.Appl.Polym.Sci, 54, 1855-1861. 

Carr ME. 1994a. Preparation of cationic starch containing quaternary ammonium substituents by reactive twin-screw extrusion processing. J Appl Polym Sci 54 1855-1861. 

White, J. L. 1990. Twin Screw Extrusion (Hauser, Munich). Xanthos, M., Ed. 1992. Reactive Extrusion (Hauser, Munich). 

Example 3. Hydrolysis in an Extruder.69 PET reactive extrusion experiments were carried out on a 25-mm Berstorff ZE25 corotating twin-screw extruder with a barrel length-to-screw ratio of 28 1. The extruder consisted of six barrel sections equipped for heating, cooling, and controlling the temperature of each section of the extruder. Initially reaction extrusion of PET and water was performed with cold water at room temperature injected into the extruder. Typical operating conditions were reaction temperatures of 230-265° C, extruder speeds... 

Homopolymers and copolymers from amido-sulfonic acid or salt containing monomers can be prepared by reactive extrusion, preferably in a twin screw extruder [1660]. The process produces a solid polymer. Copolymers of acrylamide, N-vinyl-2-pyrrolidone, and sodium-2-acrylamido-2-methyl-propane sulfonate have been proposed to be active as fluid loss agents. Another component of the formulations is the sodium salt of naphthalene formaldehyde sulfonate [207]. The fluid loss additive is mixed with hydraulic cements in suitable amounts. 

SAN can be modified, for example by grafting. For example, maleic anhydride (MA) can be grafted onto SAN. This process occurs preferably in a twin-screw extruder by reactive extrusion. An advantage of reactive extrusion is the absence of solvent as the reaction... 

Carr et al.119 investigated grafting via reactive extrusion of starch with cationic methacrylate, acrylamide and acrylonitrile monomers. Starch, monomer and CAN initiator were metered into a twin-screw extruder at starch contents of approximately 35% solids. The cationic methacrylate monomer showed poor reactivity during extrusion, with essentially no add-on. Acrylamide-starch systems (1 1 w/w) gave conversions of approximately 20% and add-ons of 16% to 18%. Acrylonitrile displayed the greatest reactivity during extrusion, with conversions of 74% and 63% for 1 1 and 1 2 w/w acrylonitrile/starch ratios, respectively. The corresponding add-ons were 27% and 42%. 

Wang, Q., Chen, Y.H., Liu, Y., Yin, H., Nico, A., and Kierkels, R. 2004. Performance of an intumescent-flame-retardant master batch synthesized by twin-screw reactive extrusion Effect of the polypropylene carrier resin. Polym. Int. 53 439 148. 

Reactive extrusion takes place when the twin screw system is designed to incorporate one or more chemical reactions during the process, such as grafting or even polymerization. Grafting is the process of attaching pendant molecules onto the backbone of a polymer chain. For example, a small concentration of maleic anhydride can be incorporated into polypropylene to make the... 

Michaeli, W., Grefenstein, A. Engineering analysis and design of twin-screw extruders for reactive extrusion. Advances in Polymer Technology 14(4), 263-276 (1995)... 

Fig. 3 Ti,ed-3/n - relation of oligoamide 6 (controlled degradation by TMAn). t]red in o-dichlorobenzene/o-cresol, c = 0.2 gdl lab series lab reaction in a stirred glass vessel extrusion series reactive extrusion in a twin-screw extruder (ZSK 28, Werner Pfleiderer) [5]...

The use of modified PTFE micropowder in combination with the mechanism of the controlled degradation of polyamide and the utilisation of melt-mixing devices like a lab melt mixer or twin-screw extruders are the basis of the reactive compa-tibilisation of the completely immiscible polymers. On the basis of the discussed mechanism PTFE polyamide block copolymers are formed by reactive extrusion ... 

Choulak et al. (2004) Polymerization of caprolactone A one-dimensional dynamic model of a twin-screw reactive extrusion Predicts pressure, filling ratio, temperature, molar conversion profiles and residencetime distributions under various operating conditions... 

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