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The miscibility of the base polymer poly (vinyl chloride) (PVC) and the extractant Aliquat 336 in polymer inclusion membranes (PIMs) was investigated by characterisation of thermal transitions using differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The extractions of Cd (II) and Zn (II) using PVC/Aliquat 336 PIMs with different base polymer/extractant composition and different extraction temperature were also investigated. Changes in the PIM's heat capacity measured by DSC were small, thus, could only be used to determine the glass transition temperature (Tg) of PIMs with low Aliquat 336 content. On the other hand, DMA results clearly identify the (Tg) and melting temperature (Tm) of separate PVC and Aliquat 336 rich phases in the PIMs. Results reported here indicate that the PVC/Aliquat 336 PIMs are phase separated. This phase separation has important implications to the extraction of target metallic ions by PIMs. Extraction studies showed that the extraction of metallic ions occurred only when the proportion of Aliquat 336 in PIMs was about 30 wt.% or higher. The extraction rate could be improved by increasing the temperature and thus the target ion transport in the Aliquat 336 phase.

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Electrospun fibres and polymer inclusion membranes (PIMs) were prepared from polyvinyl chloride (PVC) and Aliquat 336. Morphological and thermomechanical properties of the electrospun mats differed notably from those of PIMs. The plasticizing effect of Aliquat 336 on electrospun PVC/Aliquat 336 fibres was confirmed by the shifting of the glass transition temperature (Tg). By contrast, Aliquat 336 did not act as a plasticizer in PIMs as Tg was independent of Aliquat 336 concentration. Cadmium extraction to electrospun fibres could occur at a lower Aliquat 336 content (i.e. 6 wt.%) compared with PIMs. At 40 wt.% Aliquat 336 content, both PIMs and electrospun fibrous mats exhibited similar extraction rate.