A series of ‘pellicular’ type supports were fabricated by direct gamma‐radiation‐mediated graft polymerisation of styrene onto polypropylene, followed by aminomethylation. Raman spectroscopy was used for measuring the level of penetration of polystyrene graft into polypropylene, and other structural features such as density of graft and depth of functionalisation. The kinetics of the coupling of fluorenylmethylcarbamate (Fmoc)‐labelled amino acids, to the aminomethylated polystyrene grafts have been measured by UV absorption followed cleavage of the Fmoc chromophore. The Raman spectroscopy results showed that for this series of experiments the calculated rate coefficient for coupling of Fmoc‐labelled amino acids was primarily dependent on graft thickness, but was also influenced by the proportion of polystyrene graft to polypropylene. In general, it was also shown that with increasing loading capacity of support the calculated rate coefficient for amino‐acid coupling decreased correspondingly. In addition, a support that had both a high rate coefficient and a high loading capacity was prepared from polypropylene base material with a co‐continuous porous structure (high surface area). Copyright © 2003 Society of Chemical Industry

Siloxane-based side-chain liquid crystalline polymers (SCLCP) can be induced to phase separate by annealing near the clearing point in the biphasic region. This has been observed by differential scanning calorimetry (DSC), in which the isotropization endotherm becomes split, and in optical microscopy experiments. The effect was observed in all samples, independent of the chemical structure of the SCLCP synthesized. Only annealing at or below the maximum of the DSC clearing point endotherm was effective in inducing biphasic separation. When the samples were reheated above the clearing point, the demixed phases persisted for varying lengths of time, dependent on the nature of the spacer group covalently linking the mesogen side group to the siloxane backbone. Optical microscopy supports the demixing, which is proposed to be due to the distribution in molecular weight of the siloxane backbone. The effect of annealing in the biphasic region on the crystalline melting point and the glass transition was also examined. The number of precipitations of the SCLCP, which leads to a change in molecular weight distribution, also has an effect on the rate of the separation process.

Several series of stilbene derivatives for possible use as smart additives in polymers used as packaging films have been prepared and characterized. Differential scanning calorimetry was performed on some of the stilbenes in order to determine any liquid crystal properties. Those compounds which had multiple phase transitions were also shown to have two liquid crystalline phases according to optical microscopy.

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