scholarly journals Brønsted base mediated one-pot synthesis of catechol-ended amphiphilic polysarcosine-b-poly(N-butyl glycine) diblock copolypeptoids

2019 ◽  
Vol 91 (3) ◽  
pp. 363-374
Author(s):  
Hailemariam Gebru ◽  
Xin Wang ◽  
Zhenjiang Li ◽  
Jingjing Liu ◽  
Jiaxi Xu ◽  
...  
Keyword(s):  
Ring Opening ◽  
Diblock Copolymers ◽  
Aqueous Dispersion ◽  
Functionalized Polymers ◽  
One Pot ◽  
Manganese Oxide Nanoparticles ◽  
Molecular Weights ◽  
Dopamine Hydrochloride ◽  
Brønsted Base ◽  
Catechol Moiety

Abstract Catechol moiety offers a versatile platform in the preparation of functionalized polymers, but it is not usually compatible with catalysis in polymerizations. To address these challenges, we suggest employment of one Brønsted base in masking the activity of catechol moiety and to modulate the polymerization. Based on this strategy, the ring-opening polymerization (ROP) of sarcosine N-carboxyanhydrides (Sar-NCA) was carried out using dopamine hydrochloride as an initiator and triethylamine as a Brønsted base. PSar with predicted molecular weights (Mn,NMR=3.7 kg mol−1) and narrow dispersities (Đ<1.13) was prepared. Catechol initiator was successfully linked to PSar end as confirmed by MALDI-ToF MS. Subsequently, copolymerization of N-butyl glycine N-carboxyanhydrides (Bu-Gly-NCA) from the PSar in one-pot produced catechol end-functionalized amphiphilic polysarcosine-block-poly(N-butyl glycine) diblock copolypeptoids (cat-PSar-b-PGlyBu). Further, cat-PSar-b-PGlyBu enabled the aqueous dispersion of manganese oxide nanoparticles which was attributable to the anchor of the diblock copolymers onto the surface of the nanoparticles. The strategy for catechol masking and polymerization mediating by one Brønsted base offered a new avenue into the synthesis of catechol-ended block copolymers.

scholarly journals One-Pot Synthesis of Star Copolymers by the Combination of Metal-Free ATRP and ROP Processes

Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1577 ◽  
Author(s):  
Gorkem Yilmaz
Keyword(s):  
Visible Light Irradiation ◽  
Ring Opening ◽  
Reaction Medium ◽  
Ring Opening Polymerization ◽  
One Pot ◽  
Metal Free ◽  
Molecular Weights ◽  
Star Copolymers ◽  
Living Polymerizations ◽  
Chromatographic Evidence

A completely metal-free strategy is demonstrated for the preparation of star copolymers by combining atom transfer radical polymerization (ATRP) and ring-opening polymerization (ROP) for the syntheses of block copolymers. These two different metal-free controlled/living polymerizations are simultaneously realized in one reaction medium in an orthogonal manner. For this purpose, a specific core with functional groups capable of initiating both polymerization types is synthesized. Next, vinyl and lactone monomers are simultaneously polymerized under visible light irradiation using specific catalysts. Spectral and chromatographic evidence demonstrates the success of the strategy as star copolymers are synthesized with controlled molecular weights and narrow distributions.

A switch from anionic to bifunctional H-bonding catalyzed ring-opening polymerizations towards polyether–polyester diblock copolymers

2018 ◽  
Vol 9 (2) ◽  
pp. 154-159 ◽  
Author(s):  
Yaya Liu ◽  
Xin Wang ◽  
Zhenjiang Li ◽  
Fulan Wei ◽  
Hui Zhu ◽  
...  
Keyword(s):  
Ring Opening ◽  
Diblock Copolymers ◽  
One Pot ◽  
Cyclic Esters

A switch of an anionic ROP of epoxides into a bifunctional H-bonding ROP of cyclic esters paved a new avenue to one-pot, sequential, and block copolymerizations to previously rare polyether-block-polyester copolymers.

scholarly journals Diblock dialternating terpolymers by one-step/one-pot highly selective organocatalytic multimonomer polymerization

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jiaxi Xu ◽  
Xin Wang ◽  
Nikos Hadjichristidis
Keyword(s):  
Ring Opening ◽  
Polymeric Materials ◽  
Structural Diversity ◽  
One Pot ◽  
Molecular Weights ◽  
Molecular Weight Distributions ◽  
Weight Distributions ◽  
One Step ◽  
The One

AbstractThe synthesis of well-defined block copolymers from a mixture of monomers without additional actions (“one-pot/one-step”) is an ideal and industrially valuable method. In addition, the presence of controlled alternating sequences in one or both blocks increases the structural diversity of polymeric materials, but, at the same time, the synthetic difficulty. Here we show that the “one-pot/one-step” ring-opening terpolymerization of a mixture of three monomers (N-sulfonyl aziridines; cyclic anhydrides and epoxides), with tert-butylimino-tris(dimethylamino)phosphorene (t-BuP1) as a catalyst, results in perfect diblock dialternating terpolymers having a sharp junction between the two blocks, with highly-controllable molecular weights and narrow molecular weight distributions (Ð < 1.08). The organocatalyst switches between two distinct polymerization cycles without any external stimulus, showing high monomer selectivity and kinetic control. The proposed mechanism is based on NMR, in-situ FTIR, SEC, MALDI-ToF, reactivity ratios, and kinetics studies.

scholarly journals Amphiphilic diblock copolymer of hydrophilic-functionalized lactone and lactide via switchable organocatalytic polymerization

RSC Advances ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. 1905-1908
Author(s):  
Jinmei Bai ◽  
Xiaoying Tang ◽  
Yuan Zhang ◽  
Jingjing Lin ◽  
Minfeng Li
Keyword(s):  
Particle Size ◽  
Diblock Copolymer ◽  
Ring Opening ◽  
Diblock Copolymers ◽  
Main Chain ◽  
Ring Opening Polymerization ◽  
Acid Base ◽  
One Pot ◽  
Amphiphilic Diblock Copolymers ◽  
Organocatalytic Polymerization

Main-chain degradable amphiphilic diblock copolymers prepared by one-pot ring-opening polymerization via actively manipulating catalytic states of an acid–base catalytic system were capable of forming stable micelle with optimal particle size.

Stereoretentive Ring-Opening Metathesis Polymerization to Access All-cis Poly(p-phenylene vinylene)s with Living Characteristics

2020 ◽  
Author(s):  
Ting-Wei Hsu ◽  
Cheoljae Kim ◽  
Quentin Michaudel
Keyword(s):  
Organic Material ◽  
Ring Opening ◽  
Diblock Copolymers ◽  
Conductive Polymer ◽  
Synthetic Methods ◽  
Phenylene Vinylene ◽  
Ring Opening Metathesis Polymerization ◽  
Metathesis Polymerization ◽  
Molecular Weights ◽  
Responsive Polymers

Poly(p-phenylene vinylene)s (PPVs), a staple of the conductive polymer family, consist of alternating alkene and phenyl groups in conjugation. The physical properties of this organic material are intimately linked to the cis/trans configuration of the alkene groups. While many synthetic methods afford PPVs with alltrans stereochemistry, very few deliver the all-cis congeners. We report herein the first synthesis of all-cis PPVs with living characteristics via stereoretentive ring-opening metathesis polymerization (ROMP). Exquisite catalyst control allows for the preparation of homopolymers or diblock copolymers with perfect stereoselectivity, narrow dispersities, and predictable molecular weights. All-cis PPVs can then serve as light-responsive polymers through clean photoisomerization of the stilbenoid units.

Stereoretentive Ring-Opening Metathesis Polymerization to Access All-cis Poly(p-phenylene vinylene)s with Living Characteristics

2020 ◽  
Author(s):  
Ting-Wei Hsu ◽  
Cheoljae Kim ◽  
Quentin Michaudel
Keyword(s):  
Organic Material ◽  
Ring Opening ◽  
Diblock Copolymers ◽  
Conductive Polymer ◽  
Synthetic Methods ◽  
Phenylene Vinylene ◽  
Ring Opening Metathesis Polymerization ◽  
Metathesis Polymerization ◽  
Molecular Weights ◽  
Responsive Polymers

Poly(p-phenylene vinylene)s (PPVs), a staple of the conductive polymer family, consist of alternating alkene and phenyl groups in conjugation. The physical properties of this organic material are intimately linked to the cis/trans configuration of the alkene groups. While many synthetic methods afford PPVs with alltrans stereochemistry, very few deliver the all-cis congeners. We report herein the first synthesis of all-cis PPVs with living characteristics via stereoretentive ring-opening metathesis polymerization (ROMP). Exquisite catalyst control allows for the preparation of homopolymers or diblock copolymers with perfect stereoselectivity, narrow dispersities, and predictable molecular weights. All-cis PPVs can then serve as light-responsive polymers through clean photoisomerization of the stilbenoid units.

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