Synthesis of Block Copolymers of Varying Architecture Through Suppression of Transesterification during Coordinated Anionic Ring Opening Polymerization

Well-defined di- and triblock copolymers consisting ofε-caprolactone (CL), L-lactide (LA), and trimethylene carbonate (TMC) were synthesized via “PLA first route” in coordinated anionic ring opening polymerization/copolymerization (CAROP) with tin (II) octoate as catalyst. The desired block structure was preserved by use of protective additiveα-methylstyrene by preventing the transesterification side-reactions. MALDI-TOF analysis revealed that the protection mechanism is associated withα-methylstyrene and tin (II) octoate complexation. Additionally, it was shown that use ofα-methylstyrene in ring opening polymerization allowed the formation of polyesters with high molar mass.

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Using Triethylborane to Manipulate Reactivity Ratios in Epoxide-Anhydride Copolymerization: Application to the Synthesis of Polyethers with Degradable Ester Functions

Molecules ◽

10.3390/molecules27020466 ◽

2022 ◽

Vol 27 (2) ◽

pp. 466

Author(s):

Vamshi K. Chidara ◽

Yves Gnanou ◽

Xiaoshuang Feng

Keyword(s):

Ethylene Oxide ◽

Ring Opening ◽

Molar Mass ◽

Reactivity Ratio ◽

Reactivity Ratios ◽

High Molar Mass ◽

Alternating Copolymers ◽

Poly Ethylene Oxide ◽

Anionic Ring ◽

Poly Ethylene

The anionic ring-opening copolymerization (ROCOP) of epoxides, namely of ethylene oxide (EO), with anhydrides (AH) generally produces strictly alternating copolymers. With triethylborane (TEB)-assisted ROCOP of EO with AH, statistical copolymers of high molar mass including ether and ester units could be obtained. In the presence of TEB, the reactivity ratio of EO (rEO), which is normally equal to 0 in its absence, could be progressively raised to values lower than 1 or higher than 1. Conditions were even found to obtain rEO equal or close to 1. Samples of P(EO-co-ester) with minimal compositional drift could be synthesized; upon basic degradation of their ester linkages, these samples afforded poly(ethylene oxide) (PEO) diol samples of narrow molar mass distribution. In other cases where rEO were lower or higher than 1, the PEO diol samples eventually isolated after degradation exhibited a broader distribution of molar masses because of the compositional drift of initial P(EO-co-ester) samples.

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High Molar Mass Poly(trimethylene carbonate) by Ph2BiOEt and Ph2BiBr-Initiated Ring-Opening Polymerizations

Journal of Macromolecular Science Part A ◽

10.1080/10601320902724800 ◽

2009 ◽

Vol 46 (4) ◽

pp. 353-359 ◽

Cited By ~ 8

Author(s):

Hans R. Kricheldorf ◽

Gesa Behnken ◽

Gert Schwarz ◽

Peter Simon ◽

Maren Brinkmann

Keyword(s):

Ring Opening ◽

Molar Mass ◽

Trimethylene Carbonate ◽

High Molar Mass

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Synthesis and Characterization of Polyphosphazenes Modified with Hydroxyethyl Methacrylate and Lactic Acid

International Journal of Polymer Science ◽

10.1155/2013/645869 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Evelyn Carolina Martínez Ceballos ◽

Ricardo Vera Graziano ◽

Gonzalo Martínez Barrera ◽

Oscar Olea Mejía

Keyword(s):

Lactic Acid ◽

Ring Opening ◽

Room Temperature ◽

Block Structure ◽

Ring Opening Polymerization ◽

Synthesis And Characterization ◽

Poly Lactic Acid ◽

Hydroxyethyl Methacrylate ◽

H Nmr

Poly(dichlorophosphazene) was prepared by melt ring-opening polymerization of the hexachlorocyclotriphosphazene. Poly[bis(2-hydroxyethyl-methacrylate)-phosphazene] and poly[(2-hydroxyethyl-methacrylate)-graft-poly(lactic-acid)-phosphazene] were obtained by nucleophilic condensation reactions at different concentrations of the substituents. The properties of the synthesized copolymers were assessed by FTIR,1H-NMR and31P-NMR, thermal analysis (DSC-TGA), and electron microscopy (SEM). The copolymers have a block structure and show twoTg's below room temperature. They are stable up to a temperature of 100°C. The type of the substituents attached to the PZ backbone determines the morphology of the polymers.

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