Polymerization electrical discharge

Active sites created by an electric discharge method were being used for graft copolymerization by Akutin et al. (130). When a solution of a polymer in a suitable monomer is subjected to high voltage electric discharge polymerization of monomer is initiated as a result of the pressure impulses acting on the system. The authors studied the copolymerization of methyl methacrylate onto polyvinyl chloride, and of vinyl chloride onto ethylcellulose. 

The deposition of organic films by plasma polymerization is an important application of non-thennal plasmas 1301. Plasma polymers are fonned at the electrodes and the walls of electrical discharges containing organic vapours. Oily products, soft soluble films as well as hard brittle deposits and powders are fonned. The properties of plasma... 

The reaction of gaseous SO2 or SO3 with O2 in a silent electric discharge gives colourless polymeric condensates of composition S03+ t (0 < jc < 1). These materials are derived from yS-SO3 by random substitution of oxo-bridges by peroxo-bridges ... 

Thallium(I) hydride has been identified spectroscopically in the products of an electric discharge in hydrogen at a thallium cathode, or from thallium and atomic hydrogen.343 An unstable polymeric solid has also been reported.344 The borohydride TIBH4 can be obtained by reacting Tl1 compounds with LiBHU, and T1A1H4 is formed similarly 344 the borohydride, which has an ionic lattice, can also be prepared from KBH4 and aqueous TlNOs-345... 

As described in the previous chapter, in the work on electrolytic polymerization which has appeared in the literature, the active species were formed by an electrode reaction from the compounds added to the reaction system and thus initiated polymerization. However, the possibility has been considered of direct electron transfer from the cathode to monomer or from monomer to the anode forming radical-anion or -cation, followed by initiating polymerization. Polymerization of styrene initiated by an electron has been observed when the monomer was exposed to the electric discharge of a Tesla coil (74), y-radiation (75, 16) and to cathode rays from a generator of the resonant transformer type (77). 

Harteck179 was the first to report that RNO could polymerize. He passed hydrogen through an electric discharge and then into NO, and was able to trap a yellow solid of empirical formula (HNO)n at liquid air temperature. This solid decomposed on warming. 

Sulfur tetroxide is fonned by reaction of pure oxygen and sulfur dioxide under the silent electric discharge. It is not obtained pure, but in a variable SCVSO4 ratio, and as a polymerized white solid. Another peroxide. (SC OOSC O), which is written as S2O7, is known. 

Polymeric silicon chlorides One of the first detailed studies of the silicon chlorides was published by Besson and Fournier34) in 1909. The authors found that a compound (SiCl2) was formed during silent electrical discharge in SiHCl3/H2 mixtures. 

The action of the silent electric discharge upon organic compounds takes its starting point in the observation that oxygen under its influence is polymerized to ozone.. Although the work done in this field, which until recently was chiefly carried on by the French school, has not yet shown great practical results, we need not doubt that these phenomena deserve... 

The material deposition that occurs in the low-pressure electrical discharge has been discussed under various terminologies such as plasma polymerization (PP), plasma-enhanced chemical vapor deposition (PECVD), plasma-assisted chemical vapor deposition (PACVD), plasma chemical vapor deposition (PCVD), and so forth [1]. However, none of these terminologies seems to represent the phenomenon adequately. The plasma aspect in the low-pressure discharge is remote, although it plays a key role in creating the environment from which material deposition occurs to the extent that no chemical reaction occurs without the plasma. In this sense, PECVD and PACVD could be out of the context in many cases in which nothing happens without plasma. In such cases, PP or PCVD would describe the phenomenon better. If the substrate was not heated substantially above the ambient temperature, the use of PECVD or PACVD should be avoided. 

Plasma polymerization or PCVD Electrical discharge Gas Coupled... 

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