Tailor-made block copolymers of <scp>l</scp>-, <scp>d</scp>- and <i>rac</i>-lactides and ε-caprolactone <i>via</i> one-pot sequential ring opening polymerization by pyridylamidozinc(<scp>ii</scp>) catalysts

D’Auria, Ilaria; D’Alterio, Massimo Christian; Tedesco, Consiglia; Pellecchia, Claudio

doi:10.1039/c9ra07133d

Cited by 30 publications

(44 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The synthesis of CL/LA copolymers has been widely investigated in recent years, focusing on either block or random copolymers [ 16 , 17 , 18 , 19 , 20 ]. Copolymers of CL and LA generally show softer character in comparison with the PLA and PCL homo-polymers.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Thermo-Rheological and Shape Memory Properties of Block and Random Copolymers of Lactide and ε-Caprolactone

2021

View full text Add to dashboard Cite

Biodegradable block and random copolymers have attracted numerous research interests in different areas, due to their capability to provide a broad range of properties. In this paper, an efficient strategy has been reported for preparing biodegradable PCL-PLA copolymers with improved thermal, mechanical and rheological properties. Two block-copolymers are synthesized by sequential addition of the cyclic esters lactide (L-LA or D,L-LA) and ε-caprolactone (CL) in presence of a dimethyl(salicylaldiminato)aluminium compound. The random copolymer of L-LA and CL was synthetized by using the same catalyst. Chain structure, molar mass, thermal, rheological and mechanical properties are characterized by NMR, SEC, TGA, DSC, Rheometry and DMTA. Experimental results show that by changing the stereochemistry and monomer distribution of the copolymers it is possible to obtain a variety of properties. Promising shape-memory properties are also observed in the di-block copolymers characterized by the co-crystallization of CL and L-LA segments. These materials show great potential to substitute oil-based polymers for packaging, electronics, and medicine applications.

show abstract

Section: Introductionmentioning

confidence: 99%

“…Synthetic strategies have therefore been used to control the design of the polymeric chains. Several research efforts have focused on the synthesis of well-defined LA/CL copolymeric chain, either block [ 17 , 18 , 20 , 24 ], or random [ 19 , 25 , 26 , 27 , 28 ].…”

Section: Introductionmentioning

confidence: 99%

Thermo-Rheological and Shape Memory Properties of Block and Random Copolymers of Lactide and ε-Caprolactone

2021

View full text Add to dashboard Cite

show abstract

“…A wide range of elements is capable of binding / coordinating esters and promoting polymerization reactions, [ 15,16 ] and common metals that are used as the replacement of tin in the ROP are aluminum, [ 17–21 ] magnesium, [ 21–24 ] calcium, [ 24–26 ] and zinc. [ 20,21,24,26–38 ] Furthermore and in addition to the metal itself, an appropriate ligand system is crucial for an efficient ROP, and ligand design helps to optimize the catalytically active species in terms of activity and selectivity. [ 16 ] Cooperative effects originating from dinuclear complexes recently received significant interest, [ 39–48 ] and the related bimetallic catalysts often excel their mononuclear counterparts.…”

Section: Introductionmentioning

confidence: 99%

Catalytic Activity of Various β‐Diketiminate Zinc Complexes toward the Ring‐Opening Polymerization of Caprolactone and Derivatives

Köhler

Rinke

Fiederling

et al. 2021

Macro Chemistry & Physics

View full text Add to dashboard Cite

The ring‐opening polymerization (ROP) of lactones is mainly catalyzed by tin(II) octanoate Sn(Oct)2, due to its efficiency and easy handling despite the toxic issues of tin. Herein, two novel dinuclear bis(β‐diketiminate) complexes with flexible alkylene bridging groups (1,2‐ethylene and 1,3‐propylene) and biocompatible zinc centers are introduced. The complexes are obtained by deprotonation of the protio‐ligands with Zn(HMDS)2 and fully characterized. Afterwards the complexes are studied regarding their catalytic activity towards the ROP of caprolactones. Briefly, ε‐caprolactone (CL), ε‐phenyl‐ε‐caprolactone (phCL) and ε‐methyl‐ε‐caprolactone (meCL) with and without benzyl alcohol (BnOH) as initiator in toluene are homopolymerized and compared to the known dinuclear 1,4‐phenylene bridged bis(β‐diketiminate) zinc catalyst and the mononuclear counterpart. Thereby, the catalysts are classified upon their efficiency by in situ IR measurements, selectivity, and polymerization control by size exclusion chromatography (SEC) of samples, which are terminated at 60% conversion. The novel zinc catalysts prevent Sn(Oct)2 typical molar mass broadening, show slower reaction rates than 1,4‐phenylene bridged bis(β‐diketiminate) and improve control compared to the mononuclear relative. However, a drastic loss of polymerization control resulting in high molar masses and polydispersities occurrs in the absence of BnOH. Furthermore, these complexes allow the ROP of phCL but are inactive for meCL.

show abstract

“…BCPs of l ‐, d ‐ and rac‐lactides and 3‐caprolactone were synthesized by one‐pot ROP in the presence of pyridylamidozinc(II) catalysts under mild reaction conditions in short reaction time. DSC analyses confirm the formation of highly isotactic di‐BCPs that crystallized in the high melting stereo complex phase 65 …”

Section: Biomedical Applications Of Bcpsmentioning

confidence: 79%

Recent developments in biodegradable block copolymers

Tekale

Rottenberg

Ingle

et al. 2021

Polymers for Advanced Techs

View full text Add to dashboard Cite

Block copolymers consist of two or more segments of polymer chains in a typical arrangement through connected covalent bonds. Biodegradable block copolymers have emerged as useful carriers for controlled drug release, tissue engineering, and other biomedical applications due to their ability to form colloidal systems and tunable properties. This review focuses on recent advancements in the synthesis, characterization, and biomedical applications of biodegradable block copolymers.

show abstract

Tailor-made block copolymers of l-, d- and rac-lactides and ε-caprolactone via one-pot sequential ring opening polymerization by pyridylamidozinc(ii) catalysts

Abstract: New 3-coordinated Zn ROP catalysts afford lactide stereo-block copolymers with variable block lengths and steric structures and diblock ε-caprolactone-lactide copolymers at room temperature and in short reaction times.

Cited by 30 publications

References 53 publications

Thermo-Rheological and Shape Memory Properties of Block and Random Copolymers of Lactide and ε-Caprolactone

Thermo-Rheological and Shape Memory Properties of Block and Random Copolymers of Lactide and ε-Caprolactone

Catalytic Activity of Various β‐Diketiminate Zinc Complexes toward the Ring‐Opening Polymerization of Caprolactone and Derivatives

Recent developments in biodegradable block copolymers

Contact Info

Product

Resources

About