Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.777109
Title: Studies on the hydrochlorination of rubber latex
Author: Carbarns, Thomas
Awarding Body: University of Glasgow
Current Institution: University of Glasgow
Date of Award: 1957
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Abstract:
A technique described by earlier workers (6) is used to follow the kinetics of hydrochlorination of several natural and synthetic polyisoprene latexes by means of density measurements. The main purpose is to study the mechanism of the particle surface locus reaction involving an outer skin of about three molecular layers of polymer. A theoretical mechanism proposed by Gordon (11) is successfully fitted to the experimental data. The mechanism treats the double bonds of the polymer as fixed on a pseudo-lattice, and considers a reactive species such as a solvated ion pair (H2Cl+. Cl-) to diffuse inwards across the particle surface to react with these bonds. The reagent has an exceedingly low equilibrium concentration in the aqueous phase surrounding the polymer particle (~10-13 mole/l.); inside the non-polar polymer it has a short life-time (~10-19 sec.) after which it reverts to inactive covalent HCl, unless it finds a double bond as reaction partner or diffuses back into the aqueous phase. This generalised Hill-Hermans mechanism of diffusion-reaction accomodates well the kinetic effects observed v/hen the pressure of HCl, the temperature, or the particle size of the latex are varied. A specially fine synthetic polyisoprene latex (Latex Vl) of average particle diameter ~180 A was prepared for these studies, in which half the particle mass was accessible to the surface locus mechanism. The small effect on the surface and bulk locus rates of admixture of sulphuric acid with the aqueous phase has been investigated. The study of bulk locus kinetics has been extended to include runs at 11/2 and 21/2 atm. HCl pressure on natural latex.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.777109  DOI: Not available
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