Precision polymer synthesis by controlled radical polymerization: Fusing the progress from polymer chemistry and reaction engineering

Progress in Polymer Science, Journal Year: 2022, Volume and Issue: 130, P. 101555 - 101555

Published: May 7, 2022

Language: Английский

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General route to design polymer molecular weight distributions through flow chemistry

Nature Communications, Journal Year: 2020, Volume and Issue: 11(1)

Published: June 18, 2020

Abstract The properties of a polymer are known to be intrinsically related its molecular weight distribution (MWD); however, previous methodologies MWD control do not use design and result in arbitrary shaped MWDs. Here we report precise synthesis protocol for producing targeted with simple use, chemistry agnostic computer-controlled tubular flow reactor. To support the development this protocol, constructed general reactor rules by combining fluid mechanical principles, polymerization kinetics, experiments. ring opening lactide, anionic styrene, metathesis used as model polymerizations develop synthesize profiles. derivation mathematical enables quantitative prediction experimental results, provides tool explore limits any protocol.

Language: Английский

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Where Biology and Traditional Polymers Meet: The Potential of Associating Sequence-Defined Polymers for Materials Science

JACS Au, Journal Year: 2021, Volume and Issue: 1(10), P. 1556 - 1571

Published: Aug. 26, 2021

Polymers with precisely defined monomeric sequences present an exquisite tool for controlling material properties by harnessing both the robustness of synthetic polymers and ability to tailor inter- intramolecular interactions so crucial many biological materials. While polymer scientists traditionally synthesized studied physics long molecules best described their statistical nature, derive highly tailored functions from controlled sequences. Therefore, significant effort has been applied toward developing new methods synthesizing, characterizing, understanding non-natural sequence-defined polymers. This perspective considers synergistic advantages that can be achieved via tailoring precise sequence control attributes traditional in a single system. Here, we focus on potential associating systems, unique properties, such as enhanced proton conductivity, attained incorporating sequence. In particular, examine these materials key model systems studying previously unresolvable questions including role chain shape near interfaces how compatibilization between dissimilar blocks. Finally, discuss critical challenges─in truly scalable approaches, characterization modeling tools, robust assembly pathways─that must overcome attain achieve ubiquity.

Language: Английский

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Tailoring polymer dispersity by mixing chain transfer agents in PET-RAFT polymerization

Polymer Chemistry, Journal Year: 2020, Volume and Issue: 11(31), P. 4968 - 4972

Published: Jan. 1, 2020

Here we report a simple and versatile batch methodology to tailor polymer dispersity utilizing PET-RAFT polymerization.

Language: Английский

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Tailoring Polymer Dispersity in Photoinduced Iron-Catalyzed ATRP

ACS Macro Letters, Journal Year: 2020, Volume and Issue: 9(4), P. 459 - 463

Published: March 16, 2020

Although dispersity (Đ) plays an important role in controlling polymer properties, there are very few chemical methods that can sufficiently tune it. Here we report a simple, batch, and environmentally benign photoinduced iron-catalyzed ATRP methodology enables the efficient control of Đ for both homopolymers block copolymers. We show by judiciously varying concentration FeBr3/TBABr catalyst, range dispersities be obtained (1.18 < 1.80) while maintaining monomodal molecular weight distributions. High end-group fidelity was confirmed MALDI-ToF-MS further supported synthesis situ copolymers where second could controlled upon demand. Importantly, through use low ppm amounts perfect temporal attained during intermittent "on/off" cycles. This work considerably expands toolbox tuning homo-

Language: Английский

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Machine learning for polymeric materials: an introduction

Polymer International, Journal Year: 2021, Volume and Issue: 71(5), P. 537 - 542

Published: Dec. 4, 2021

Abstract Polymers are incredibly versatile materials and have become ubiquitous. Increasingly, researchers using data science polymer informatics to design new understand their structure–property relationships. Polymer is an emerging field. While there many useful tools databases available, not widely utilized. Herein, we introduce the field of discuss some available tools. We cover how share data, approaches for preparing a dataset machine learning recent applications property prediction synthesis. © 2021 Society Industrial Chemistry.

Language: Английский

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Precise Control of Both Dispersity and Molecular Weight Distribution Shape by Polymer Blending

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(35), P. 19383 - 19388

Published: June 16, 2021

The breadth and the shape of molecular weight distributions can significantly influence fundamental polymer properties that are critical for various applications. However, current approaches require extensive synthesis multiple polymers, limited in dispersity precision typically incapable simultaneously controlling both distributions. Here we report a simplified approach, whereby on mixing two polymers (one high Đ one low Đ), any intermediate value be obtained (e.g. from 1.08 to 1.84). Unrivalled is achieved, with values even nearest 0.01 1.37→1.38→1.39→1.40→1.41→1.42→1.43→1.44→1.45), while maintaining fairly monomodal This approach was also employed control obtain diblock copolymers accuracy. straightforward nature our methodology alongside its compatibility wide range polymerisation protocols ATRP, RAFT), expands toolbox tailored polymeric materials makes them accessible all researchers.

Language: Английский

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A co-anchoring strategy for the synthesis of polar bimodal polyethylene

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: March 15, 2023

Since polar groups can poison the metal centers in catalysts, incorporation of comonomers usually comes at expense catalytic activity and polymer molecular weight. In this contribution, we demonstrate bimodal polyethylene as a potential solution to trade-off. The more-polar/more-branched low-molecular-weight fraction provides polarity processability, while less-polar/less-branched high-molecular-weight mechanical melt properties. To achieve high miscibility between these two fractions, three synthetic routes are investigated: mixtures homogeneous separately supported heterogeneous co-anchoring strategy (CAS) heterogenize different catalysts on one solid support. CAS route is only viable for synthesis with good level entanglement minimal phase separation. This produces polyolefin materials excellent properties, surface/dyeing gas barrier well extrudability 3D-printability.

Language: Английский

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Precise Synthesis of Optically Active and Thermo‐degradable Poly(trifluoromethyl methylene) with Circularly Polarized Luminescence

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(20)

Published: March 14, 2023

Developing high performance and environment-friendly fluoropolymers is greatly desired. In this work, we found that 2-diazo-1,1,1-trifluoroethane can be polymerized by air-stable alkyne-palladium(II) catalysts following a living polymerization mechanism, affording fluoropolymer, poly(trifluoromethyl methylene) in yield with controlled molar mass low dispersity. This polymer bears trifluoromethyl on every main chain atom thus has good resistance to chemical corrosion, hydrophobicity, excellent dielectric constant loss. Due the steric hindrance between pendants, synthetic twist into stable helix. The one-handed preferred helices synthesized using chiral PdII -catalysts exhibit optical activity circularly polarized luminescence. Remarkably, such completely degraded (E)-1,1,1,4,4,4-hexafluorobut-2-ene at temperatures (>280 °C). Additionally, taking advantage of end, further modified.

Language: Английский

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Shifting Boundaries: Controlling Molecular Weight Distribution Shape for Mechanically Enhanced Thermoplastic Elastomers

Macromolecules, Journal Year: 2020, Volume and Issue: 53(17), P. 7479 - 7486

Published: Aug. 24, 2020

Thermoplastic elastomers (TPEs) based on polystyrene (PS) are commonplace in society. The elastomeric properties of these materials often sacrificed to increase mechanical such as stiffness, strength, and toughness. We sought produce stiff, strong, tough TPEs that retain their by shifting the lamellar phase boundary toward higher PS content. By precisely controlling molecular weight distribution (MWD) shape one block polystyrene-block-polyisoprene-block-polystyrene (SIS), we produced continuous at atypically high volume fractions, from 0.33 triblocks with a narrow MWD ∼0.39 broadened block. Furthermore, observed hexagonal/lamellar coexistence fraction 0.39 when first was asymmetric. These exhibit enhanced consistent fractions morphologies.

Language: Английский

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