%0 Journal Article
%T Highly Branched Poly(¦Á-Methylene-¦Ã-Butyrolactone) from Ring-Opening Homopolymerization
%A Pascal Binda
%A Zakiya Barnes
%A Dechristian Guthrie
%A Rasaan Ford
%J Open Journal of Polymer Chemistry
%P 76-91
%@ 2165-6711
%D 2017
%I Scientific Research Publishing
%R 10.4236/ojpchem.2017.74006
%X <div style=\"text-align:justify;\">
	New heteroleptic lanthanide complex [L<sup>1I</sup>LaN{Si(CH<sub>3</sub>)<sub>2</sub>}] (1) containing tridentate
[ONO] ancillary ligand was synthesized from an acid-base ligand exchange
reaction with ligands H<sub>2</sub>L<sup>1</sup> and corresponding homoleptic lanthanide
compound La[N{Si(CH<sub>3</sub>)<sub>3</sub>}<sub>2</sub>]<sub>3</sub>. Meanwhile, dimeric complexes [L<sup>1</sup>LaCl] (2)
and [L<sup>1I</sup>LaCl] (3) were prepared from salt metathesis reaction between one
equivalent of ligands H<sub>2</sub>L<sup>I,II</sup>, three equivalent of NaN{Si(CH<sub>3</sub>)<sub>3</sub>}<sub>2</sub>, and one equivalent
of LaCl<sub>3</sub>. These compounds were characterized by nuclear magnetic resonance
(300 MHz) and elemental analysis. These complexes were used as catalysts in
the ring-opening homopolymerization of ¦Á-methylene-¦Ã-butyrolactone. While
compound <strong>1</strong> did not show any significant reactivity, compounds <strong>2</strong> and <strong>3</strong> gave
significant amount of highly branched poly(¦Á-methylene-¦Ã-butyrolactone) as
confirmed by <sup>1</sup>H NMR spectroscopy and Malvern¡¯s triple detector GPCMax
analysis in DMSO with molecular weights of over 500,000 Dalton. The
glass-transition temperatures of the branched polymer samples were determined
using a Dynamic Mechanical Analyzer, DMA Q800.
</div>
%K Lanthanide
%K &lt
%K i&gt
%K ¦Á&lt
%K /i&gt
%K -Methylene-&lt
%K i&gt
%K ¦Ã&lt
%K /i&gt
%K -Butyrolactone
%K Polyesters
%K Ring-Opening Polymerization
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=80744