scholarly journals Macromolecular Dyes by Chromophore-Initiated Ring Opening Polymerization of L-Lactide

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1979
Author(s):  
Francesca Cicogna ◽  
Guido Giachi ◽  
Luca Rosi ◽  
Elisa Passaglia ◽  
Serena Coiai ◽  
...  

End functionalized polylactides are prepared by ring opening polymerization of L-lactide in the presence of stannous octoate (Sn(Oct)2). Three chromophores, 9H-carbazol-ethanol (CA), 9-fluorenyl-methanol (FM), and 2-(4-(2-chloro-4-nitrophenylazo)-N-ethylphenylamino)ethanol (Disperse Red 13, DR), are for the first time used as co-initiators in the polymerization process. The polymerization reaction is initiated by conventional thermal treatment, but in the case of FM, microwave-assisted polymerization is also carried out. CA and FM absorb and emit in the UV portion of the electromagnetic spectrum, whereas DR absorbs in the visible part. The obtained end-capped polylactides derivatives show the same photophysical properties as the initiator, so they are “macromolecular dyes” (MDs) that can be used “as synthesized” or can be blended with commercial poly(lactic acid) (PLA). The blends of PLA with MDs have ultraviolet-visible (UV-Vis) absorption and fluorescence emission features similar to that of MDs and thermal properties typical of PLA. Finally, migration tests, carried out onto the blends of PLA with MDs and PLA with free chromophores, show that MDs are less released than free chromophores both in solution and in the solid phase.


2021 ◽  
Vol 11 (4) ◽  
pp. 1561
Author(s):  
Gabrielle Foran ◽  
Nina Verdier ◽  
David Lepage ◽  
Arnaud Prébé ◽  
David Aymé-Perrot ◽  
...  

Solid polymer electrolytes have been widely proposed for use in all solid-state lithium batteries. Advantages of polymer electrolytes over liquid and ceramic electrolytes include their flexibility, tunability and easy processability. An additional benefit of using some types of polymers for electrolytes is that they can be processed without the use of solvents. An example of polymers that are compatible with solvent-free processing is epoxide-containing precursors that can form films via the lithium salt-catalyzed epoxide ring opening polymerization reaction. Many polymers with epoxide functional groups are liquid under ambient conditions and can be used to directly dissolve lithium salts, allowing the reaction to be performed in a single reaction vessel under mild conditions. The existence of a variety of epoxide-containing polymers opens the possibility for significant customization of the resultant films. This review discusses several varieties of epoxide-based polymer electrolytes (polyethylene, silicone-based, amine and plasticizer-containing) and to compare them based on their thermal and electrochemical properties.



2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Evelyn Carolina Martínez Ceballos ◽  
Ricardo Vera Graziano ◽  
Gonzalo Martínez Barrera ◽  
Oscar Olea Mejía

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.





2016 ◽  
Vol 49 (13) ◽  
pp. 4699-4713 ◽  
Author(s):  
Nicholas J. Sherck ◽  
Hyun Chang Kim ◽  
You-Yeon Won






2019 ◽  
Vol 3 (2) ◽  
pp. 112-119
Author(s):  
Jesús Miguel Contreras Ramírez ◽  
Dimas Medina ◽  
Francisco López-Carrasquero ◽  
Ricardo Rafael Contreras

Background: The synthesis of the aliphatic polyesters obtained by the ring opening polymerization has been achieved using as initiators a large amount of organometallic compounds derivative from: Alkali metals, alkaline earth metals, transition metals and lanthanide metals. Of all these compounds, the lanthanide derivatives have acquired great importance in the synthesis of aliphatic polyesters, since these show a greater catalytic activity and also can provide polymer with characteristics that will be very useful in the design of biomaterials. Objective: It was proposed the synthesis of poly(L-lactida) (PL-LA) through a ring opening polymerization process of L-lactide initiated with samarium(III) acetate (Sm(OAc)3) under solvent-free melt conditions. The influence of different parameters of reaction, such as temperature, time, molar ratio monomer to initiator, on typical variables of polymers, e.g., conversion, dispersity, and molar mass, were analyzed. Methods: All polymerizations were carried out under solvent-free melt conditions in ampoules-like flasks, equipped with a magnetic stirrer. The obtained polyesters were characterized by size exclusion chromatography (SEC) and 1H-NMR. Results: The Sm(OAc)3 induces the polymerization of L-LA at high conversion, and produce polyesters with number-average molecular weights of 1.00 x 103 to 30.00 x 103 Dalton. The 1H-NMR analysis indicates a typical polymerization mechanism of coordination-insertion, with a breakdown of the acyl-oxygen bond of the L-LA. Conclusion: Sm(OAc)3 was an effective initiator for the ring-opening polymerization of L-LA. SEC chromatography showed that, at high temperatures and prolonged reaction times, the molar mass of the polyester decreases, which is associated with the transesterification collateral reactions that occur during the polymerization process.



2019 ◽  
Vol 27 (4) ◽  
pp. 847-861 ◽  
Author(s):  
Chaniga Chuensangjun ◽  
Kyohei Kanomata ◽  
Takuya Kitaoka ◽  
Yusuf Chisti ◽  
Sarote Sirisansaneeyakul


Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 800 ◽  
Author(s):  
Orlando Santoro ◽  
Xin Zhang ◽  
Carl Redshaw

This review describes the recent advances (from 2008 onwards) in the use of Schiff-base metal complexes as catalysts for the ring opening polymerization (ROP) of cyclic esters. The synthesis and structure of the metal complexes, as well as all aspects concerning the polymerization process and the characteristics of the polymers formed, will be discussed.



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