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Mechanochemical polymerization of lactide is carried out by using ball milling. Mechanical energy from collisions between the balls and the vessel efficiently promotes an organic-base-mediated metal- and solvent-free solid-state polymerization. Investigation of the parameters of the ball-milling synthesis revealed that the degree of lactide ring-opening polymerization could be modulated by the ball-milling time, vibration frequency, mass of the ball media, and liquid-assisted grinding. Liquid-assisted grinding was found to be an especially important factor for achieving a high degree of mechanochemical polymerization. Although polymer-chain scission from the strong collision energy prevented mechanical-force-driven high-molecular-weight polymer synthesis, the addition of only a small amount of liquid enabled sufficient energy dissipation and poly(lactic acid) was thereby obtained with a molecular weight of over 1×10 5  g mol -1 ., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This comprehensive review aims to provide an in‐depth analysis of the catalytic performance of 1,5,7‐triazabicyclo[4,4,0]dec‐5‐ene (TBD) in polymer synthesis. TBD, a well‐established organic superbase, possesses a distinctive bifunctional character that grants it exceptional capabilities, particularly in processes such as transesterification or transamidation. TBD has garnered considerable attention since its initial report by Hedrick and Waymouth in 2006, and it has played a pivotal role in diverse polymerization reactions. Its versatility spans various polymerization modes, including chain‐growth and step‐growth polymerization, post‐polymerization modification, and network thermoset formation. More recently, its utility has extended to the green chemical recycling of polymers. By providing an encompassing overview of TBD's historical journey, this review delves into its past accomplishments while shedding light on its present and future potential to organocatalysts in polymer science. [ABSTRACT FROM AUTHOR]

Mechanochemistry – the utilization of mechanical forces to induce chemical reactions – is a rarely considered tool for polymer synthesis. It offers numerous advantages such as reduced solvent consumption, accessibility of novel structures, and the avoidance of problems posed by low monomer solubility and fast precipitation. Consequently, the development of new high-performance materials based on mechanochemically synthesised polymers has drawn much interest, particularly from the perspective of green chemistry. This review covers the constructive mechanochemical synthesis of polymers, starting from early examples and progressing to the current state of the art while emphasising linear and porous polymers as well as post-polymerisation modifications. [ABSTRACT FROM AUTHOR]

A new sequential post‐polymerization modification route has been developed for the synthesis of multifunctional polymers from a simple aldehyde polymer. In the first modification step, a template polymer derived from the radical polymerization of 4‐vinyl benzaldehyde undergoes Rh‐catalyzed hydroacylation with alkenes to furnish a group of ketone polymers. In the second modification step, Schiff base formation with alkoxy ammonium salts introduces a second group—an oxime functionality. Both the steps are highly efficient, introducing evenly distributed dual functionalities at the same position. [ABSTRACT FROM AUTHOR]

Despite their superior stability and facile handling, ionic polymers have limited solubility in most organic solvents, restricting the range of substrates and reaction conditions to which they can be applied. To overcome this solubility issue, the present study presents a solvent‐free mechanochemical reaction. Specifically, a post‐polymerization modification of ammonium‐functionalized polyether was demonstrated using a solvent‐free vibrational ball‐milling technique. The formation of imine bonds between the ionic polymer and an aromatic aldehyde led to the complete conversion to imine within 1 h without any bond breakage on the polymer backbone. The viability of this approach for a wide range of aldehydes was also evaluated, highlighting the potential of the mechanochemical post‐polymerization modification of polymers that are inaccessible by conventional solution approaches. [ABSTRACT FROM AUTHOR]

ABSTRACT Post-polymerization modification is an important synthetic method to produce macromolecules with various chemical and physical properties. With this technique, functional groups of polymer molecules within the same structural scaffold can be varied, and thus, accurate research on structure-property relationships is possible. To add practicality, the direct post-polymerization of commodity polymers has been pursued, but only limited success has been realized. In this report, a study on various transesterification methods for the synthesis of functional polyacrylates beginning with a poly(methyl acrylate) (PMA), one common acrylate polymer, is presented. The Zn-based catalytic system, a combination of Zn4(OCOCF3)6O and 4-dimethylaminopyridine with instant methanol removal, exhibited the highest reactivity among many catalysts and conditions. Assorted alcohols were reacted with PMA to produce the corresponding polyacrylates. This method was successfully extended to post-polymerization modification of a PMA-containing block copolymer, PS- b-PMA and synthesis of acrylate copolymers with functional group density control. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2554-2560 [ABSTRACT FROM AUTHOR]

The first example of metal-free hydrosilylation polymerization between dienes and disilanes is developed by using a borane catalyst, B(C6F5)3 to replace precious transitionmetal-based systems. Under the easy-to-handle and mild conditions, a step-growth polymerization of two readily available diene and disilane units was achieved with high degrees of polymerization. Various combinations of dienes and disilanes produced polycarbosilanes with a broad range of structures and properties. [ABSTRACT FROM AUTHOR]

We report a method for the synthesis of multisegmentedpolycarbonate graft copolymers. Using a β-diiminate zinc catalystwith a norbornene carboxylate initiator, we achieved living blockcopolymerizations of functionalized cyclohexene oxides and CO2, yielding norbornenyl-terminated macromonomers with variableblock sequences. Subsequent ring-opening metathesis polymerizationof the norbornenyl-terminated macromonomers produced segmented graftcopolymers. This method provides a facile route to core–shellstructures with readily controllable molecular parameters. [ABSTRACT FROM AUTHOR]

Keywords: imine bond; mechanochemistry; polymers; post-polymerization modification; solid-state reactions EN imine bond mechanochemistry polymers post-polymerization modification solid-state reactions 3633 3633 1 09/22/21 20210920 NES 210920 B The Cover Feature b shows the post-polymerization modification of ammonium-functionalized polyether using a solvent-free vibrational ball-milling technique. Cover Feature: Solvent-Free Mechanochemical Post-Polymerization Modification of Ionic Polymers (ChemSusChem 18/2021) Imine bond, mechanochemistry, polymers, post-polymerization modification, solid-state reactions. [Extracted from the article]