Tubular reactor, plasma polymerization

The hydrodynamic factors that influence the plasma polymerization process pose a complicated problem and are of importance in the application of plasma for thin film coatings. When two reaction chambers with different shapes or sizes are used and when plasma polymerization of the same monomer is operated under the same operational conditions of RF power, monomer flow rate, pressure in the reaction chamber etc., the two plasma polymers formed in the two reaction chambers are never identical because of the differences in the hydrodynamic factors. In this sense, plasma polymerization is a reactor-dependent process. Yasuda and Hirotsu [22] systematically investigated the effects of hydrodynamic factors on the plasma polymerization process. They studied the effect of the monomer flow pattern on the polymer deposition rate in a tubular reactor. The polymer deposition rate is a function of the location in the chamber. The distribution of the polymer deposition rate is mainly determined by the distance from the plasma zone and the... 

Fig. 6 Schematic representation of the vertical tubular reactor for plasma polymerization onto powders [41]...

The effects of the discharge power on the distribution of polymer deposition in a tubular reactor (Fig. 20.1) are shown in Figures 20.19-20.22. Figure 20.19 depicts the change in polymer deposition pattern due to the discharge power observed in the plasma polymerization of styrene at a fixed flow rate of 5.6 seem. 

Figure 3.3 illustrates the tubular reactor for the plasma polymerization. The reactor diameter is 75 mm and its length is 300 mm. A porous polysulfone substrate membrane (Brunswick SDM 90-25, average pore diameter 0.1 /im) disk of 70 mm in diameter is placed in the reactor. After evacuating the reactor, a mixed... 

Figure 3.3. Tubular reactor for plasma polymerization. (Reproduced with permission of the author.)...

The plasma system consisted of a standard vacuum pump and a tubular Pyrex reactor with a 13.56 MHz RF generator coupled to it using external copper electrodes [26]. During the experiments, surfaces of PVC powder and PE granules were modified in carbon tetrachloride and vinyl chloride plasma for the first polymer, and in acetylene plasma for the latter. The plasma treatment conditions are presented in Table 7. Plasma is known to yield mainly surface modifications with a minimum (if any) of plasma polymerization. The oligomer VCO was also used without application of plasma to prepare reference blends. 

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