The adsorption of vinyl chloride and vinylidene chloride monomers on their polymers

 

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dc.contributor.advisor Linder, Peter W en_ZA
dc.contributor.author Torrington, Ralph George en_ZA
dc.date.accessioned 2016-03-21T19:25:14Z
dc.date.available 2016-03-21T19:25:14Z
dc.date.issued 1970 en_ZA
dc.identifier.citation Torrington, R. 1970. The adsorption of vinyl chloride and vinylidene chloride monomers on their polymers. University of Cape Town. en_ZA
dc.identifier.uri http://hdl.handle.net/11427/18119
dc.description.abstract Following semi-quantitative investigations of the kinetics and equilibria of:- (a) Vinyl chloride monomer vapour adsorbed on polyvinyl chloride; (b) Vinylidene chloride monomer vapour adsorbed on polyvinyl chloride; (c) Vinylidene chloride monomer vapour adsorbed on polyvinylidene chloride; it became evident that, for a number of reasons detailed in the text, it would be worthwhile to study system (a) in detail. Thorough investigations were therefore made at the two temperatures, 25⁰ C and 42.6⁰ C, and in the pressure range 20 torr to 600 torr, with the following results: (i) Attainment of equilibrium, especially at the higher pressures, was very slow and as a result only approximate isotherms could be obtained. These isotherms were shown to exhibit hysteresis. Comparison of the amount of monomer adsorbed at the higher pressures within the above limits, with the amount of krypton required to cover the surface with a monolayer, indicated that multimolecular adsorption occurred. The ascending branches of the isotherms appeared to obey the Freundlich isotherm and the approximate isosteric heats of adsorption calculated from the equilibrium data fell off linearly as the logarithm of the amount of monomer adsorbed increased; as would be expected if the Freundlich isotherm were obeyed. The values of the heats of adsorption found were such that comparison between them and the latent heat of vapourisation of the monomer made it difficult to decide whether the first layer on the surface was chemisorbed or physically adsorbed. (ii) The kinetic data showed that there was always an initial instantaneous adsorption which was reversible towards pressure, followed by a very much slower uptake of monomer. The kinetics of the slow uptake of monomer was studied, at the two temperatures, under both constant pressure and constant volume conditions and was shown to consist of two processes. en_ZA
dc.language.iso eng en_ZA
dc.subject.other Chemistry en_ZA
dc.title The adsorption of vinyl chloride and vinylidene chloride monomers on their polymers en_ZA
dc.type Doctoral Thesis
uct.type.publication Research en_ZA
uct.type.resource Thesis en_ZA
dc.publisher.institution University of Cape Town
dc.publisher.faculty Faculty of Science en_ZA
dc.publisher.department Department of Chemistry en_ZA
dc.type.qualificationlevel Doctoral
dc.type.qualificationname PhD en_ZA
uct.type.filetype Text
uct.type.filetype Image
dc.identifier.apacitation Torrington, R. G. (1970). <i>The adsorption of vinyl chloride and vinylidene chloride monomers on their polymers</i>. (Thesis). University of Cape Town ,Faculty of Science ,Department of Chemistry. Retrieved from http://hdl.handle.net/11427/18119 en_ZA
dc.identifier.chicagocitation Torrington, Ralph George. <i>"The adsorption of vinyl chloride and vinylidene chloride monomers on their polymers."</i> Thesis., University of Cape Town ,Faculty of Science ,Department of Chemistry, 1970. http://hdl.handle.net/11427/18119 en_ZA
dc.identifier.vancouvercitation Torrington RG. The adsorption of vinyl chloride and vinylidene chloride monomers on their polymers. [Thesis]. University of Cape Town ,Faculty of Science ,Department of Chemistry, 1970 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/18119 en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Torrington, Ralph George AB - Following semi-quantitative investigations of the kinetics and equilibria of:- (a) Vinyl chloride monomer vapour adsorbed on polyvinyl chloride; (b) Vinylidene chloride monomer vapour adsorbed on polyvinyl chloride; (c) Vinylidene chloride monomer vapour adsorbed on polyvinylidene chloride; it became evident that, for a number of reasons detailed in the text, it would be worthwhile to study system (a) in detail. Thorough investigations were therefore made at the two temperatures, 25⁰ C and 42.6⁰ C, and in the pressure range 20 torr to 600 torr, with the following results: (i) Attainment of equilibrium, especially at the higher pressures, was very slow and as a result only approximate isotherms could be obtained. These isotherms were shown to exhibit hysteresis. Comparison of the amount of monomer adsorbed at the higher pressures within the above limits, with the amount of krypton required to cover the surface with a monolayer, indicated that multimolecular adsorption occurred. The ascending branches of the isotherms appeared to obey the Freundlich isotherm and the approximate isosteric heats of adsorption calculated from the equilibrium data fell off linearly as the logarithm of the amount of monomer adsorbed increased; as would be expected if the Freundlich isotherm were obeyed. The values of the heats of adsorption found were such that comparison between them and the latent heat of vapourisation of the monomer made it difficult to decide whether the first layer on the surface was chemisorbed or physically adsorbed. (ii) The kinetic data showed that there was always an initial instantaneous adsorption which was reversible towards pressure, followed by a very much slower uptake of monomer. The kinetics of the slow uptake of monomer was studied, at the two temperatures, under both constant pressure and constant volume conditions and was shown to consist of two processes. DA - 1970 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 1970 T1 - The adsorption of vinyl chloride and vinylidene chloride monomers on their polymers TI - The adsorption of vinyl chloride and vinylidene chloride monomers on their polymers UR - http://hdl.handle.net/11427/18119 ER - en_ZA


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