Access to Poly-β-Peptides with Functionalized Side Chains and End Groups via Controlled Ring-Opening Polymerization of β-Lactams

2009 ◽  
Vol 131 (4) ◽  
pp. 1589-1597 ◽  
Author(s):  
Jihua Zhang ◽  
Denis A. Kissounko ◽  
Sarah E. Lee ◽  
Samuel H. Gellman ◽  
Shannon S. Stahl
Keyword(s):  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Side Chains ◽  
End Groups ◽  
Functionalized Side

scholarly journals Anionic Polymerization of β-Butyrolactone Initiated with Sodium Phenoxides. The Effect of the Initiator Basicity/Nucleophilicity on the ROP Mechanism

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1221 ◽  
Author(s):  
Adrian Domiński ◽  
Tomasz Konieczny ◽  
Magdalena Zięba ◽  
Magdalena Klim ◽  
Piotr Kurcok
Keyword(s):  
Anionic Polymerization ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Elimination Reaction ◽  
Mild Conditions ◽  
Acidic Proton ◽  
End Groups ◽  
Anionic Ring

It was shown that selected sodium phenoxide derivatives with different basicity and nucleophilicity, such as sodium p-nitrophenoxide, p-chlorophenoxide, 1-napthoxide, phenoxide and p-methoxyphenoxide, are effective initiators in anionic ring-opening polymerization (AROP) of β-butyrolactone in mild conditions. It was found that phenoxides as initiators in anionic ring-opening polymerization of β-butyrolactone behave as strong nucleophiles, or weak nucleophiles, as well as Brønsted bases. The resulting polyesters possessing hydroxy, phenoxy and crotonate initial groups are formed respectively by the attack of phenoxide anion at (i) C2 followed by an elimination reaction with hydroxide formation, (ii) C4 and (iii) abstraction of acidic proton at C3. The obtained poly(3-hydroxybutyrate) possesses carboxylate growing species. The ratio of the observed initial groups strongly depends on the basicity and nucleophilicity of the sodium phenoxide derivative used as initiator. The proposed mechanism of this polymerization describes the reactions leading to formation of observed end groups. Moreover, the possibility of formation of a crotonate group during the propagation step of this polymerization is also discussed.

Mixed Molecular Brushes with PLLA and PS Side Chains Prepared by AGET ATRP and Ring-Opening Polymerization

2006 ◽  
Vol 39 (22) ◽  
pp. 7513-7519 ◽  
Author(s):  
Dongxia Wu ◽  
Yongfang Yang ◽  
Xiaohui Cheng ◽  
Li Liu ◽  
Jia Tian ◽  
...  
Keyword(s):  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Side Chains ◽  
Aget Atrp ◽  
Molecular Brushes

The Study of Thermolplastic Elastomer Based on Polyamide 6: Preparation, Morphology and Mechanical Performance

2011 ◽  
Vol 332-334 ◽  
pp. 1490-1493
Author(s):  
Chun Wang Yi ◽  
Nan Fan Li ◽  
Chao Sheng Wang ◽  
Zhi Han Peng ◽  
Shi Yan Chen
Keyword(s):  
Adipic Acid ◽  
Acid Content ◽  
Ring Opening ◽  
Mechanical Performance ◽  
Thermoplastic Elastomer ◽  
Polyamide 6 ◽  
Ring Opening Polymerization ◽  
Polymerization Process ◽  
End Groups ◽  
Mechanical Performances

In this study,a new thermoplastic elastomer based on polyamid 6, and polytetrahydrofuran was prepared by continuous hydrolytic ring-opening polymerization process. The effective of adipic acid content on the number-average molecular and the content of amino end groups was investigated. The morphology deduce of TPMP, mechanical performances were also investigated.

Mesophase and Optical Properties of Side Chain Copolyacrylate with Mesogens and OLLA Segments Side Chains

2011 ◽  
Vol 181-182 ◽  
pp. 397-400
Author(s):  
Ya Ping Liu ◽  
Zhuo Hua Li ◽  
Ling Min Sun ◽  
Run Tao Dong ◽  
Hong Ru Chen ◽  
...  
Keyword(s):  
Ring Opening ◽  
Optical Rotation ◽  
Helical Structure ◽  
Ring Opening Polymerization ◽  
Side Chain ◽  
Side Chains ◽  
Induce Effect ◽  
Phase Structures ◽  
Acrylate Esters ◽  
Phase Behaviors

Thermal properties and phase behaviors of series of newly synthesized copolyacrylate esters with oligomeric-L-LA (OLLA) segments (DP = 10-40) and mesogens as side chains were characterized. The OLLAs prepared by ring opening polymerization of L-LA with active HO-group were modified to form polymerizable acrylate esters and then copolymerized with polymerizable mesogens. The thermal behaviors of these copolyacrylate esters were studied by DSC and POM measurements and phase structures by XRD measurements. The mesogens showed very good induce effect on the formation of layered structures. CD measurements were used to determine the helical structure and the optical rotation power of the side chain copolyacrylate esters.

scholarly journals Pentamethylcyclopentadienyl Molybdenum(V) Complexes Derived from Iodoanilines: Synthesis, Structure, and ROP of ε-Caprolactone

Catalysts ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1554
Author(s):  
Tian Xing ◽  
Mark R. J. Elsegood ◽  
Sophie H. Dale ◽  
Carl Redshaw
Keyword(s):  
Molecular Weight ◽  
Comparative Studies ◽  
Ring Opening ◽  
Kinetic Studies ◽  
Ring Opening Polymerization ◽  
Molecular Structures ◽  
Low Molecular Weight ◽  
End Groups ◽  
Amine Complex ◽  
Reaction Stoichiometry

The reaction of [Mo(η-C5Me5)Cl4] with the ortho-, meta-, or para-iodo-functionalized anilines 2-IC6H4NH2, 3-IC6H4NH2, 4-IC6H4NH2 yields imido or amine products of the type [Mo(η-C5Me5)Cl2(IC6H4N)] (2-I, 1, 3-I, 3, 4-I, 5) or [Mo(η-C5Me5)Cl4(IC6H4NH2)] (3-I, 2, 4-I, 4), respectively, depending on the reaction stoichiometry/conditions; we were unable to isolate an amine complex of the 2-I derivative. The reaction of [Mo(η-C5Me5)Cl4] with one equivalent of 2-I,4-FC6H3NH2 in the presence of Et3N afforded [Mo(η-C5Me5)Cl2(2-I,4-FC6H3N)]·MeCN (6·MeCN), which, upon exposure to air, afforded the Mo(VI) imido complex [Mo(η-C5Me5)Cl3(2-I,4-FC6H3N)] (7). For comparative studies, the structure of the aniline (C6H5NH2)-derived complex [Mo(η-C5Me5)Cl2(2-C6H3N)] (8) has also been prepared. The molecular structures of 1–8 have been determined and reveal packing in the form of zig-zag chains or ladders. The complexes catalyze, in the presence of benzyl alcohol under N2, the ring-opening polymerization (ROP) of ε-caprolactone affording relatively low molecular weight products. The MALDI-ToF spectra indicate that a number of polymer series bearing a variety of end groups are formed. Conducting the ROPs as melts or under air results in the isolation of higher molecular weight products, again bearing a variety of end groups. Kinetic studies reveal the aniline-derived imido complex 8 performs best, whilst a meta-iodo substituent and a Mo(V) centre are also found to be beneficial. The structures of the side products 2-IC6H4NH3Cl and 3-IC6H4NH3Cl are also reported.

Synthesis of Polylactide with Thiol End Groups

2003 ◽  
Vol 68 (6) ◽  
pp. 1131-1140 ◽  
Author(s):  
Štěpán Popelka ◽  
František Rypáček
Keyword(s):  
Allyl Alcohol ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Synthetic Methods ◽  
Thiol Groups ◽  
End Groups ◽  
Synthetic Routes ◽  
Subsequent Modification

Four synthetic routes to poly(L-lactide) with thiol end groups based on ring-opening polymerization of L-lactide (LA) catalysed with tin(II) 2-ethylhexanoate (Sn(Oct)2) are reported. The following alcohols were used as co-initiators of polymerization: 2-sulfanylethan-1-ol, 2-[(2,4-dinitrophenyl)sulfanyl]ethan-1-ol, 2-(tritylsulfanyl)ethan-1-ol and allyl alcohol. End groups introduced into polymers by co-initiators were transformed to thiol groups by a subsequent modification reaction. The efficiencies of the used synthetic methods were evaluated and discussed. The best results were obtained with co-initiator 2-(tritylsulfanyl)ethan-1-ol.

scholarly journals Cationic Polymerization of Hexamethylcyclotrisiloxane in Excess Water

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4402
Author(s):  
Quentin Barnes ◽  
Claire Longuet ◽  
François Ganachaud
Keyword(s):  
Cationic Polymerization ◽  
Ring Opening ◽  
Room Temperature ◽  
Colloidal Stability ◽  
Short Communication ◽  
Ring Opening Polymerization ◽  
Chain Extension ◽  
Excess Water ◽  
End Groups ◽  
Cationic Ring Opening Polymerization

Ring-opening ionic polymerization of cyclosiloxanes in dispersed media has long been discovered, and is nowadays both fundamentally studied and practically used. In this short communication, we show some preliminary results on the cationic ring-opening polymerization of hexamethylcyclotrisiloxane (D3), a crystalline strained cycle, in water. Depending on the catalyst or/and surfactants used, polymers of various molar masses are prepared in a straightforward way. Emphasis is given here on experiments conducted with tris(pentafluorophenyl)borane (BCF), where high-molar polymers were generated at room temperature. In surfactant-free conditions, µm-sized droplets are stabilized by silanol end-groups of thus generated amphiphilic polymers, the latter of which precipitate in the course of reaction through chain extension. Introducing various surfactants in the recipe allows generating smaller emulsions in size with close polymerization ability, but better final colloidal stability, at the expense of low small cycles’ content. A tentative mechanism is finally proposed.

High temperature reaction between poly(glycolic acid) and ε-caprolactone in ionic liquids

e-Polymers ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Souad Dali ◽  
Hervé Lefebvre ◽  
Rachid El Gharbi ◽  
Alain Fradet
Keyword(s):  
Ionic Liquids ◽  
Ring Opening ◽  
Glycolic Acid ◽  
Reaction Rate ◽  
Ring Opening Polymerization ◽  
Nmr Studies ◽  
High Temperature Reaction ◽  
End Groups ◽  
C Nmr ◽  
Interchange Reactions

Abstractε-Caprolactone (CL) was reacted with PGA oligomers in ionic liquids in the presence of Ti(OBu)4, both ring-opening polymerization initiator and polyesterification catalyst. 1H and 13C NMR studies showed that the fast polymerization of CL was followed by simultaneous slow polyesterification and ester-interchange reactions leading to random PGA/CL copolyesters after 6 h reaction. The nature of the catalyst and the ionic liquid did not influence much reaction rate. Hydroxyacetyl end-groups appeared to be much less reactive than the corresponding hydroxycaproyl end-groups, which were consumed at the beginning of reaction. The 50/50 and 60/40 oxyacetyl (G)/oxycaproyl (L) (mass-%) copolyesters were amorphous, while copolyesters containing larger amounts of G units were semi-crystalline. The variations of the Tg of all copolyesters versus composition follow the Flory-Fox law.

Brush macromolecules with thermo-sensitive coil backbones and pendant polypeptide side chains: synthesis, self-assembly and functionalization

2015 ◽  
Vol 6 (8) ◽  
pp. 1316-1324 ◽  
Author(s):  
Zheng Wei ◽  
Shuzhe Zhu ◽  
Hanying Zhao
Keyword(s):  
Self Assembly ◽  
Ring Opening ◽  
Chain Transfer ◽  
Ring Opening Polymerization ◽  
Side Chains ◽  
Reversible Addition

Macromolecular brushes with thermo-sensitive coil backbones and pendant poly(γ-benzyl-l-glutamate) side chains were synthesized by reversible addition–fragmentation chain transfer and ring-opening polymerization. Functionalization and self-assembly of the macromolecules were investigated.

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