Toru Tokimitsu

Chain transfer polymerization of methyl methacrylate initiated by organolanthanide complexes

A novel chain transfer polymerization mediated by Cp 2 *Sm(III) species and organic acids is described. The chain transfer polymerization involves the reaction of organic acids such as thiols or ketones with an active bond between samarium(III) and the enolate in a living chain and of poly(methyl methacrylate) (PMMA). This chain transfer reaction resulted in termination of the living chain end and the regeneration of the active initiator which would consist of (C 5 Me 5 ) 2 Sm(III) and deprotonated organic acids. The chain transfer polymerization was confirmed by turnover numbers (TON). tert-Butyl thiol exhibited the chain transfer reactivity effectively to control the molecular weight of PMMA without decreasing of the polymer yield and the stereoregularity. As a result of this chain transfer polymerization, thermal and optical propertics of the PMMA obtained were improved by the control of chain end groups or by reducing a large amount of the samarium initiator.

Performance of see-through prism CPV module for window integrated photovoltaics.

We have examined the performance of a see-through photovoltaics module that uses a low-concentration prism concentrator by undertaking ray-tracing analysis and an on-site experiment. The incident angle dependency of the prism concentrator makes it possible to concentrate direct solar radiation onto solar cells and transmit diffuse solar radiation. Fewer solar cells can then be used without sacrificing the conversion efficiency or lighting performance. The module generates approximately 1.15 more electricity than a conventional module while operating with 63% less solar cell area. We also introduce a design method for the concentrator geometry that adjusts the incident angle dependency for different latitude and tilt angles.