- Efficiency of liquid tin(ii): N -alkoxide initiators in the ring-opening polymerization of l-lactide: Kinetic studies by non-isothermal differential scanning calorimetry
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Novel soluble liquid tin(ii) n-butoxide (Sn(OnC4H9)2), tin(ii) n-hexoxide (Sn(OnC6H13)2), and tin(ii) n-octoxide (Sn(OnC8H17)2) initiators were synthesized for use as coordination-insertion initiators in the bulk ring-opening polymerization (ROP) of l-lac
- Chaiwon, Tawan,Meepowpan, Puttinan,Molloy, Robert,Punyodom, Winita,Sriyai, Montira
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p. 43566 - 43578
(2020/12/25)
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- Bulk polymerization of L-lactide with dibenzoylmethane Sn(II) compounds
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The bulk polymerization behavior of L-lactide monomer using dibenzoylmethane (DBM)-based Sn(II) compounds (DBM)Sn(OBu) (2) and (DBM)2Sn (3) is investigated. Compounds 2 and 3 were prepared from the reaction of Sn(OBu)2,/inf> (1) with 1 or 2 equiv of DBM,respectively. X-ray diffraction studies revealed that, while 2 exists as a dimeric form linked by 1-butoxide bridges, 3 is monomeric in the solid state. The Sn(II) centers in both compounds adopt distorted square-pyramidal geometry. Ring-opening polymerization of L-lactide with 1-3 efficiently produced poly(L-lactide)s with high molecular weight and narrow polydispersities (PDI 2 > 3, indicating that the DBM ligand causes a sluggish coordinative insertion of the lactide monomer into the Sn(II) center. In particular, the addition of dodecanol (DDO, 0.1 mol%) substantially improved the catalytic activity for all compounds. The comparative polymerization using Sn(Oct) 2 (Oct = 2-ethylhexanoate) in the absence and presence of DDO further showed that 1 is higher in activity than Sn(Oct)2 and that Sn(II) alkoxides are the actual active species in the polymerization of Llactide.
- Yoon, Sung Cheol,Park, And Seung Young,Lee, Kang Mun,Lee, Min Hyung
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p. 340 - 345
(2015/03/03)
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- PROCESS FOR THE PREPARATION OF LIQUID TIN(II) ALKOXIDES
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This invention describes the synthetic process of producing liquid tin(II) alkoxides for use as either reagents in the synthesis of lactide or as initiators in the polymerization of cyclic ester monomers to yield biodegradable polyesters. The synthetic process employs anhydrous tin(II) chloride dissolved in n-heptane and mixed with dry diethylamine. Alcohols, ROH, in which the R groups are n-C4H9, n-C6H13, and n-C8H17 are added to the reaction mixture and stirred for 12 hours. The reaction mixture isthen filtered under nitrogen or argon before being evaporated to dryness to yield the three tin(II) alkoxides, namely: tin(II) n-butoxide, tin(II) n- hexoxide, and tin(II) n-octoxide. All three tin(II) alkoxides are viscous, dark yellow liquids which are highly soluble in most common organic solvents. Furthermore,they can all be stored under an inert atmosphere for long periods without any significant change in their vi nd therefore in their effectiveness as rea ents/initiators.
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Page/Page column 9; 10
(2014/06/11)
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- ORGANOTIN COMPOUND, METHOD FOR PREPARING SAME, AND METHOD FOR PREPARING POLYLACTIDE USING SAME
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The present invention relates to an organotin compound represented by R1O-Sn-OR2 (where R1 and R2 are independently a primary, secondary, or tertiary alkyl group having 5 to 30 carbon atoms), a preparation method thereof, and a preparation method for polylactide using the organotin compound. The organotin compound of the present invention is easy to prepare and is used to prepare a polylactide resin having a high molecular weight at a high yield without using a separate initiator.
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Page/Page column 9
(2012/08/14)
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- Electrosynthesis of tin(II) alkoxides
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The anodic dissolution of tin metal in absolute alcohols yields oxoalkoxides with the general formula Sn6O4(OR) 4 (R = Me (1), Et (2), i-Pr (3)) and orthoalkoxides with the general formula Sn(OR)2 (R = n-Bu (4),
- Suslova,Turova,Kessler,Belokon
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p. 1682 - 1686
(2008/10/09)
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- Synthesis and structural characterization of tin(II) and zinc(II) derivatives of cyclic (α-hydroxyketones, including the structures of Sn(maltol)2, Sn(tropolone)2, Zn(tropolone)2, and Zn(hinokitiol)2
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Zinc(II) and tin(II) derivatives of maltol (Hmalt), ethylmaltol (HEtmalt), tropolone (Htrop), hinokitiol (Hhino), and kojic acid (Hkoj) have been prepared and characterized, and the crystal structures of M(trop)2 (M = Zn, Sn), Zn(hino)2·EtOH, and Sn(malt)2 have been determined. The Zn(trop)2 is a polymeric structure in which tropolone has both a bridging and chelating role; zinc(hino)2 crystallizes as an ethanol adduct of which the structure is a dimeric fragment of the Zn(trop)2 polymer and in which each metal is capped by a molecule of alcohol. The tin complexes are notably air-stable despite adopting monomeric pseudo-trigonal-bipyramidal structures (SnO4E; E is a stereochemically active lone electron pair) in which the ligands only chelate a single metal center.
- Barret,Mahon,Molloy,Steed,Wrightt
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p. 4384 - 4388
(2008/10/08)
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