Characterisation of complex polymer mixtures

Abstract

The polymer of intrinsic microporosity PIM-1 was synthesized following various procedures:(i) from fluoro-monomer by the conventional method, (ii) from fluoro-monomer by a hightemperature, high shear mixing method and (iii) from chloro-monomer. For a more completeunderstanding of the structure of the resultant products of a series of polymerizations underdifferent reaction conditions, a multi-detector gel permeation chromatography (GPC) methodwas established and validated. A procedure for fractionating PIM-1 using chloroformmethanol solvent mixtures was established and validated. A combination of multi-detectorGPC and matrix-assisted laser desorption/ionization - time of flight (MALDI-ToF) massspectrometry was used for the determination of molar mass distribution and to identifystructural differences between fractions and between the products from different syntheticprocedures. High molar mass samples tended to have broader molar mass distributions. BothMark-Houwink plots and hydrodynamic volume plots showed deviation from linearity at Mw= 200000 g mol-1, which was attributed to branching. A low cost route for the preparation ofPIM-1 from chloro-monomer was successfully established, though samples prepared by thisroute had broader polydispersities than those prepared from fluoro-monomers. It was foundthat stable flexible membranes were formed from samples with Mw > 83000 g mol -1.In addition, a comparison of two analytical methods for extraction and determination ofadditives in HDPE, LLDPE and PP polymers of interest to Saudi Basic IndustriesCorporation was performed. A comparison of dissolution with ultrasonic assisted extractionmethods for the determination of anti-oxidant additives in polyolefins was performed.Ultrasound assisted extraction methods were found to be superior for HDPE and LLDPE,where conventional dissolution was preferred for PP.

Date of Award	1 Aug 2011
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Stephen Yeates (Supervisor) & Peter Budd (Supervisor)