This study investigated the molecular structure of the polyhydroxyalkanoate (PHA) produced via a microbiological shake flask experiment utilizing oxidized polypropylene (PP) waste as an additional carbon source. The bacterial strain Cupriavidus necator H16 was selected as it is non-pathogenic, genetically stable, robust, and one of the best known producers of PHA. Making use of PHA oligomers, formed by controlled moderate-temperature degradation induced by carboxylate moieties, by examination of both the parent and fragmentation ions, the ESI-MS/MS analysis revealed the 3-hydroxybutyrate and randomly distributed 3-hydroxyvalerate as well as 3-hydroxyhexanoate repeat units. Thus, the bioconversion of PP solid waste to a value-added product such as PHA tert-polymer was demonstrated.

Novel methacrylate copolymers containing polysiloxane (SiMA) and mixed poly(ethyleneglycol)-perfluorohexyl side chains (MEF) were synthesised and dispersed as surface-active additives in crosslinked PDMS films. The amphiphilic behaviour of the copolymers caused surface reconstruction in water which was characterised by dynamic and static contact angle measurements and angle-resolved X-ray photoelectron spectroscopy (XPS) analysis. The XPS CF2/OCH2 ratio between the hydrophobic fluoroalkyl segments and the hydrophilic oxyethylenic segments was high (15/64) for the copolymer richest in MEF (93 mol%), which also had a high percentage of surface fluorine (∼30%). By contrast, an especially low CF2/OCH2 ratio (0/16) and a low percentage of surface fluorine (∼2%) were identified for the copolymer poorest in MEF (14 mol%). Such large differences in surface chemical composition reflected different antifouling and fouling-release properties against the green macroalga Ulva linza. Generally, the films containing the copolymer with the smallest MEF content were able to resist the settlement of zoospores better than those with a high MEF content and had a superior release of sporelings (young plants)

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