A novel approach to the recycling of polystyrene is reported here; polystyrene is converted to a biodegradable plastic, namely polyhydroxyalkanoate (PHA). This unique combinatorial approach involves the pyrolysis of polystyrene to styrene oil, followed by the bacterial conversion of the styrene oil to PHA by Pseudomonas putida CA-3 (NCIMB 41162). The pyrolysis (520 degrees C) of polystyrene in a fluidized bed reactor (Quartz sand (0.3-0.5 mm)) resulted in the generation of an oil composed of styrene (82.8% w/w) and low levels of other aromatic compounds. This styrene oil, when supplied as the sole source of carbon and energy allowed for the growth of P. putida CA-3 and PHA accumulation in shake flask experiments. Styrene oil (1 g) was converted to 62.5 mg of PHA and 250 mg of bacterial biomass in shake flasks. A 1.6-fold improvement in the yield of PHA from styrene oil was achieved by growing P. putida CA-3 in a 7.5 liter stirred tank reactor. The medium chain length PHA accumulated was comprised of monomers 6, 8, and 10 carbons in length in a molar ratio of 0.046:0.436:1.126, respectively. A single pyrolysis run and four fermentation runs resulted in the conversion of 64 g of polystyrene to 6.4 g of PHA.

Different highly substituted C1 symmetric metallocenes have been investigated for the copolymerization of ethene and norbornene. The influence of the feed ratio and the polymerization temperature were varied to characterize the polymer by means of microstructure, thermal properties and catalysts activity. The bulky structured ligands of the catalysts lead to highly stereoregular copolymers with semi‐crystalline phases even at low norbornene incorporation. Two different allyl ethers (allyl ethyl and allyl propyl ether) have been used to copolymerize with ethene using metallocene catalyst system (rac‐[Me2Si(2‐Me‐4‐(1‐Ph)Ind)2]ZrCl2/MAO). In order to investigate the influence to ether incorporation to polymer properties, we have performed experiments varying comonomers concentration in feed, polymerization temperature and ratio Al(MAO)/Zr. The higher comonomer incorporation was followed by loss of cristallinity of the produced polymer. Additionally, the catalytic activity and melting point of the polymers also decrease with increase in comonomer concentration in feed.

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