Heterogeneous catalysts for the controlled ring-opening polymerisation of rac-lactide and homogeneous silsesquioxane model complexes.
نویسندگان
چکیده
In this communication we report, for the first time, the ring-opening polymerisation in the melt of rac-lactide with heterogeneous catalysts. Homogeneous model systems based on silsesquioxanes have been prepared for comparison.
منابع مشابه
Dicationic and zwitterionic catalysts for the amine-initiated, immortal ring-opening polymerisation of rac-lactide: facile synthesis of amine-terminated, highly heterotactic PLA.
Dicationic, zwitterionic and "conventional" yttrium compounds act as catalysts for the primary or secondary amine-initiated immortal ROP of rac-lactide; amine-terminated, highly heterotactic poly(rac-lactides) with narrow polydispersities and well-controlled molecular weights are prepared in this manner.
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متن کاملSalalen aluminium complexes and their exploitation for the ring opening polymerisation of rac-lactide.
In this paper we report the first use of Al(III) salalen complexes for the ring opening polymerisation of rac-lactide. Polylactides with narrow polydispersities (PDIs range from 1.04-1.65) and moderate degrees of stereoselectivity were formed. Eight salalen Al(III) complexes have been prepared and fully characterised by solution-state NMR spectroscopy and, where appropriate, single crystal X-ra...
متن کاملZirconium complexes of bipyrrolidine derived salan ligands for the isoselective polymerisation of rac-lactide.
Herein we report the synthesis and characterisation of a series of Zr(IV) 2,2'-bipyrrolidine-salan derived complexes and their exploitation for the ring opening polymerisation of rac-lactide to afford highly isotactically enriched polymers.
متن کاملZinc-Catalyzed Highly Isoselective Ring Opening Polymerization of rac-Lactide
A family of chiral zinc amido-oxazolinate complexes are shown to be highly active and isoselective initiators for the ring-opening polymerization (ROP) of rac-lactide, yielding isotactic stereoblock polylactides (PLA) with Pm up to 0.91. This represents the highest isoselectivity observed with zinc-based catalysts for ROP of rac-lactide.
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ورودعنوان ژورنال:
- Dalton transactions
دوره 28 شماره
صفحات -
تاریخ انتشار 2008