Poly (3-hydroxyalkanoate) paint and method for the preparation thereof

Poly(3-hydroxyalkanoates) (PHAs) are used as binders for drying paint systems, wherein the poly (3-hydroxyalkanoate) component comprises poly (3-hydroxyalkanoate) containing mono- and/or poly-unsaturated side groups. Medium chain length PHAs based on unsaturated vegetable fatty acids are preferred. PHAs are used in the form of a solution in organic solvents and in the form of a dispersion in water. The PHA binders are used for the formulation of solvent-based PHA paint systems and for the formulations of PHA latexes

Hydrido rhodium diphosphite catalysts in the asymmetric hydroformylation of styrene

Chiral diphosphites based on (2R,3R)-butane-2,3-diol, (2R,4R)-pentane-2,4-diol, (2S,5S)-hexane-2,5-diol, (1S,3S)-diphenylpropane-1,3-diol and N-benzyltartarimide as chiral bridges have been used in the rhodium-catalysed asymmetric hydroformylation of styrene. Enantioselectivities up to 76% at 50% conversion have been obtained with stable hydridorhodium diphosphite catalysts. High regioselectivities (>95%) and high conversions (>99%) to 2-phenylpropanal were found under relatively mild reaction conditions [25-40°C, 9 bar of CO-H2 (1:1) pressure]. The solution structures of [RhH(L)(CO)2] complexes (L = bidentate diphosphite) have been studied; NMR and IR spectroscopic data revealed fluxional behaviour. Depending on the structure of the bridge, the diphosphite adopts equatorial-equatorial or equatorial-axial co-ordination to the rhodium. The structure and the stability of the catalysts seems to play a fundamental role in the asymmetric induction