Are RAFT and ATRP Universally Interchangeable Polymerization Methods in Network Formation?

Solid-Phase Synthesis of Well-Defined Multiblock Copolymers by Atom Transfer Radical Polymerization

Solid-phase polymer synthesis, historically rooted in peptide synthesis, has evolved into a powerful method for achieving sequence-controlled macromolecules. This study explores solid-phase polymer synthesis by covalently immobilizing growing polymer chains onto a poly(ethylene glycol) (PEG)-based resin, known as ChemMatrix (CM) resin. In contrast to traditional hydrophobic supports, CM resin's amphiphilic properties enable swelling in both polar and nonpolar solvents, simplifying filtration, washing, and drying processes. Combining atom transfer radical polymerization (ATRP) with solid-phase techniques allowed for the grafting of well-defined block copolymers in high yields. This approach is attractive for sequence-controlled polymer synthesis, successfully synthesizing di-, tri-, tetra-, and penta-block copolymers with excellent control over the molecular weight and dispersity. The study also delves into the limitations of achieving high molecular weights due to confinement within resin pores. Moreover, the versatility of the method is demonstrated through its applicability to various monomers in organic and aqueous media. This straightforward approach offers a rapid route to developing tailored block copolymers with unique structures and functionalities.

Tuning the Mechanical Properties of 3D-printed Objects by Mixing Chain Transfer Agents in Radical Promoted Cationic RAFT Polymerization

The utilization of (cationic) reversible addition-fragmentation chain transfer (RAFT) polymerization in photoinduced three-dimensional (3D) printing has emerged as a robust technique for fabricating a variety of stimuli-responsive materials. However, methods for precisely adjusting the mechanical properties of these materials remain limited, thereby constraining their broader applicability. In this study, a facile way is introduced to modulate the mechanical properties of 3D printed objects by mixing two chain transfer agents (CTAs) within a radical-promoted cationic RAFT (RPC-RAFT) polymerization-based 3D printing process. Through systematic investigations employing tensile testing and dynamic mechanical analysis (DMA), the influence of CTA concentration and molar ratio between two CTAs on the mechanical behavior of the printed objects are explored. These findings demonstrate that higher concentrations of CTAs or a greater molar ratio of the more active CTA within the mixed CTAs result in decreased Young's modulus and glass transition temperatures of the printed objects. Moreover, the tensile failure strain increased with the increasing CTA content, i.e., the samples became more ductile. This methodology broadens the toolbox available for tailoring the mechanical properties of 3D printed materials.

Characterization Methods to Determine Interpenetrating Polymer Network (IPN) in Hydrogels

Significant developments have been achieved with the invention of hydrogels. They are effective in many fields such as wastewater treatment, food, agriculture, pharmaceutical applications, and drug delivery. Although hydrogels have been used successfully in these areas, there is a need to make them better for future applications. Interpenetrating polymer networks (IPNs) can be created to make hydrogels more adjustable and suitable for a specific purpose. IPN formation is an innovative approach for polymeric systems. It brings two or more polymer networks together with entanglements. The properties of IPNs are controlled by its chemistry, crosslinking density, and morphology. Therefore, it is necessary to understand characterization methods in order to detect the formation of IPN structure and to develop the properties of hydrogels. In recent studies, IPN structure in hydrogels has been determined via chemical, physical, and mechanical methods such as Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), X-ray diffraction (XRD), and rheology methods. In this paper, these characterization methods will be explained, recent studies will be scrutinized, and the effectiveness of these methods to confirm IPN formation will be evaluated.

Interplay of Spatial and Topological Defects in Polymer Networks

Polymer networks are widely used in applications, and the formation of a network and its gel point can be predicted. However, the effects of spatial and topological heterogeneity on the resulting network structure and ultimately the mechanical properties, are less understood. To address this challenge, we generate in silico random networks of cross-linked polymer chains with controlled spatial and topological defects. While all fully reacted networks investigated in this study have the same number of end-functionalized polymer strands and cross-linkers, we vary the degree of spatial and topological heterogeneities systematically. We find that spatially heterogeneous cross-linker distributions result in a reduction in the network's primary loops with increased spatial heterogeneity, the opposite trend as observed in homogeneous networks. By performing molecular dynamics simulations, we investigated the mechanical properties of the networks. Even though spatially heterogeneous networks have more elastically active strands and cross-linkers, they break at lower extensions than the homogeneous networks and sustain slightly lower maximum stresses. Their shear moduli are higher, i.e., stiffer, than theoretically predicted, and higher than their homogeneous gel counterparts. Our results highlight that topological loop defects and spatial heterogeneities result in significantly different network structures and, ultimately, different mechanical properties.

New Chemistries for Degradable Pressure-Sensitive Adhesive Networks

With the increasing use of pressure-sensitive adhesives (PSAs) in various industries, there is a need for greater sustainability, particularly in developing polymer materials from renewable resources, as well as the reuse and recycling of materials to reduce environmental impact, reduce waste, or extend their life. Here, we outlined the required properties of PSAs which are governed by the molecular parameters (molecular weights, dispersities, molecular weight between entanglement, molecular weight between cross-links and gel content) of polymer materials which subsequently define the physical properties (storage and loss moduli, glass transition temperature) that are required for good performance in peel, tack and shear tests. The sustainable approach discussed here is the development of degradable polymer materials featuring selectively degradable linkages in the backbone. This provides a viable alternative for the design of PSAs that could overcome the 'stickies' problem and make the recycling of glass and cardboard more efficient.

Network Polymer Properties Engineered Through Polymer Backbone Dispersity and Structure

Dispersity (Ð or Mw/Mn) is an important parameter in material design and as such can significantly impact the properties of polymers. Here, polymer networks with independent control over the molecular weight and dispersity of the linear chains that form the material are developed. Using a RAFT polymerization approach, a library of polymers with dispersity ranging from 1.2-1.9 for backbone chain-length (DP) 100, and 1.4-3.1 for backbone chain-length 200 were developed and transformed to networks through post-polymerization crosslinking to form disulfide linkers. The tensile, swelling, and adhesive properties were explored, finding that both at DP 100 and DP 200 the swelling ratio, tensile strength, and extensibility were superior at intermediate dispersity (1.3-1.5 for DP 100 and 1.6-2.1 for DP 200) compared to materials with either substantially higher or lower dispersity. Furthermore, adhesive properties for materials with chains of intermediate dispersity at DP 200 revealed enhanced performance compared to the very low or high dispersity chains.

Confinement of Sustainable Carbon Dots Results in Long Afterglow Emitters and Photocatalyst for Radical Photopolymerization

Sustainable carbon dots based on cellulose, particularly carboxymethyl cellulose carbon dots (CMCCDs), were confined in an inorganic network resulting in CMCCDs@SiO2. This resulted in a material exhibiting long afterglow covering a time frame of several seconds also under air. Temperature-dependent emission spectra gave information on thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) while photocurrent experiments provided a deeper understanding of charge availability in the dark period, and therefore, its availability on the photocatalyst surface. The photo-ATRP initiator, ethyl α-bromophenylacetate (EBPA), quenched the emission from the millisecond to the nanosecond time frame indicating participation of the triplet state in photoinduced electron transfer (PET). Both free radical and controlled radical polymerization based on photo-ATRP protocol worked successfully. Metal-free photo-ATRP resulted in chain extendable macroinitiators based on a reductive mechanism with either MMA or in combination with styrene. Addition of 9 ppm Cu2+ resulted in Mw/Mn of 1.4 while an increase to 72 ppm improved uniformity of the polymers; that is Mw/Mn=1.03. Complementary experiments with kerria laca carbon dots confined materials, namely KCDs@SiO2, provided similar results. Deposition of Cu2+ (9 ppm) on the photocatalyst surface explains better uniformity of the polymers formed in the ATRP protocol.

Controlling primary chain dispersity in network polymers: elucidating the effect of dispersity on degradation

Although dispersity has been demonstrated to be instrumental in determining many polymer properties, current synthetic strategies predominantly focus on tailoring the dispersity of linear polymers. In contrast, controlling the primary chain dispersity in network polymers is much more challenging, in part due to the complex nature of the reactions, which has limited the exploration of properties and applications. Here, a one-step method to prepare networks with precisely tuned primary chain dispersity is presented. By using an acid-switchable chain transfer agent and a degradable crosslinker in PET-RAFT polymerization, the in situ crosslinking of the propagating polymer chains was achieved in a quantitative manner. The incorporation of a degradable crosslinker, not only enables the accurate quantification of the various primary chain dispersities, post-synthesis, but also allows the investigation and comparison of their respective degradation profiles. Notably, the highest dispersity networks resulted in a 40% increase in degradation time when compared to their lower dispersity analogues, demonstrating that primary chain dispersity has a substantial impact on the network degradation rate. Our experimental findings were further supported by simulations, which emphasized the importance of higher molecular weight polymer chains, found within the high dispersity materials, in extending the lifetime of the network. This methodology presents a new and promising avenue to precisely tune primary chain dispersity within networks and demonstrates that polymer dispersity is an important parameter to consider when designing degradable materials.

Exploiting the Monomer-Feeding Mechanism of RAFT Emulsion Polymerization for Polymerization-Induced Self-Assembly of Asymmetric Divinyl Monomers

We exploited the monomer-feeding mechanism of reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization to achieve the successful polymerization-induced self-assembly (PISA) of asymmetric divinyl monomers. Colloidally stable cross-linked block copolymer nanoparticles with various morphologies, such as vesicles, were directly prepared at high solids. Morphologies of the cross-linked block copolymer nanoparticles could be controlled by varying the monomer concentration, degree of polymerization (DP) of the core-forming block, and length of the macro-RAFT agent. X-ray photoelectron spectroscopy (XPS) characterization confirmed the presence of unreacted vinyl groups within the obtained block copolymer nanoparticles, providing a landscape for further functionalization via thiol-ene chemistry. Finally, the obtained block copolymer nanoparticles were employed as additives to tune the mechanical properties of hydrogels. We expect that this study not only offers considerable opportunities for the preparation of well-defined cross-linked block copolymer nanoparticles, but also provides important insights into the controlled polymerization of multivinyl monomers.

Biomass RNA for the Controlled Synthesis of Degradable Networks by Radical Polymerization

Nucleic acids extracted from biomass have emerged as sustainable and environmentally friendly building blocks for the fabrication of multifunctional materials. Until recently, the fabrication of biomass nucleic acid-based structures has been facilitated through simple crosslinking of biomass nucleic acids, which limits the possibility of material properties engineering. This study presents an approach to convert biomass RNA into an acrylic crosslinker through acyl imidazole chemistry. The number of acrylic moieties on RNA was engineered by varying the acylation conditions. The resulting RNA crosslinker can undergo radical copolymerization with various acrylic monomers, thereby offering a versatile route for creating materials with tunable properties (e.g., stiffness and hydrophobic characteristics). Further, reversible-deactivation radical polymerization methods, such as atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain transfer (RAFT), were also explored as additional approaches to engineer the hydrogel properties. The study also demonstrated the metallization of the biomass RNA-based material, thereby offering potential applications in enhancing electrical conductivity. Overall, this research expands the opportunities in biomass-based biomaterial fabrication, which allows tailored properties for diverse applications.

Customized Nanostructured Ceramics via Microphase Separation 3D Printing

To date, the restricted capability to fabricate ceramics with independently tailored nano- and macroscopic features has hindered their implementation in a wide range of crucial technological areas, including aeronautics, defense, and microelectronics. In this study, a novel approach that combines self- and digital assembly to create polymer-derived ceramics with highly controlled structures spanning from the nano- to macroscale is introduced. Polymerization-induced microphase separation of a resin during digital light processing generates materials with nanoscale morphologies, with the distinct phases consisting of either a preceramic precursor or a sacrificial polymer. By precisely controlling the molecular weight of the sacrificial polymer, the domain size of the resulting material phases can be finely tuned. Pyrolysis of the printed objects yields ceramics with complex macroscale geometries and nanoscale porosity, which display excellent thermal and oxidation resistance, and morphology-dependent thermal conduction properties. This method offers a valuable technological platform for the simplified fabrication of nanostructured ceramics with complex shapes.

Process intensification of continuous-flow seATRP by a sonicated multi-reactor setup

Simplified electrochemically mediated atom transfer radical polymerization (seATRP) is a versatile technique for synthesizing polymers with precise control and complex architecture. Continuous-flow seATRP has recently been realized by using a sonicated microreactor but still faces limitations such as relatively low conversion and difficulties in synthesizing polymers with high molecular weight. Herein, a novel multi-reactor setup is demonstrated. By tuning the currents applied to different reaction stages in the setup, 90% conversion can be achieved while maintaining relatively low dispersity (<1.35). Meanwhile, the unique design enables a wider processing window for sonication due to greater viscous attenuation in the second reactor, thus largely addressing the problem associated with high viscosity during the synthesis of high molecular weight polymers. The developed setup also offers an alternative strategy for future scale-up of continuous-flow seATRP.

Degradable, Ultraviolet-Crosslinked Pressure-Sensitive Adhesives Made from Thioester-Functional Acrylate Copolymers

Pressure-sensitive adhesives (PSAs) are made from soft, irreversibly lightly crosslinked polymers. Even after removal from surfaces, they retain insoluble networks which pose problems during the recycling of glass and cardboard. Herein, degradable PSAs are presented that provide the required performance in use but have networks that can be degraded after use. A series of copolymers was prepared through radical copolymerization of n-butyl acrylate, 4-acryloyloxy benzophenone (ABP) photo-crosslinker, and dibenzo[c,e]oxepin-5(7H)-thione (DOT) to provide degradable backbone thioesters. The optimum tack and peel strengths were found for molar contents of 0.05 mol% ABP and 0.25 mol% DOT. Degradation of the backbone thioesters through aminolysis or thiolysis led to the full dissolution of the networks, loss of adhesive properties of films (decreases in the measured tack and peel strengths), and the quick detachment of model labels from a substrate. Inclusion of DOT into PSAs offers a viable route toward degradable and recyclable packaging labels.

RAFT Polymerisation and Hypercrosslinking Improve Crosslink Homogeneity and Surface Area of Styrene Based PolyHIPEs

The influence of a polymerisation mechanism (reversible addition-fragmentation chain transfer; RAFT vs. free radical polymerisation; FRP) on the porous structure of highly porous poly(styrene-co-divinylbenzene) polymers was investigated. The highly porous polymers were synthesised via high internal phase emulsion templating (polymerizing the continuous phase of a high internal phase emulsion), utilising either FRP or RAFT processes. Furthermore, residual vinyl groups in the polymer chains were used for the subsequent crosslinking (hypercrosslinking) applying di-tert-butyl peroxide as the source of radicals. A significant difference in the specific surface area of polymers prepared by FRP (between 20 and 35 m²/g) and samples prepared by RAFT polymerisation (between 60 and 150 m²/g) was found. Based on the results from gas adsorption and solid state NMR, it could be concluded that the RAFT polymerisation affects the homogeneous distribution of the crosslinks in the highly crosslinked styrene-co-divinylbenzene polymer network. During the initial crosslinking, RAFT polymerisation leads to the increase in mesopores with diameters between 2 and 20 nm, resulting in good accessibility of polymer chains during the hypercrosslinking reaction, which is reflected in increased microporosity. The fraction of micropores created during the hypercrosslinking of polymers prepared via RAFT is around 10% of the total pore volume, which is up to 10 times more than for polymers prepared by FRP. Specific surface area, mesopore surface area, and total pore volume after hypercrosslinking reach almost the same values, regardless of the initial crosslinking. The degree of hypercrosslinking was confirmed by determination of the remaining double bonds by solid-state NMR analysis.

Mechanistic aspect for the atom transfer radical polymerization of itaconimide monomers with methyl methacrylate: a computational study

Atom transfer radical polymerization (ATRP) is a versatile & famous technique for the synthesis of well defined molecular architectures. In ATRP, there is a dynamic equilibrium exists between active & dormant species. Therefore, ATRP progress through a sequence of activation & deactivation cycles, ending upon complete monomer consumption & termination reactions are minimized. This paper presents a systematic computational study on kinetics & thermodynamics associates in the ATRP of itaconimide monomers & methyl methacrylate (MMA). For this, the copolymerization system is modeled as a unimer, dimer & trimer of various itaconimides & MMA monomer. The density functional theory with B3LYP functional & 6–31 + G(d)/LanL2DZ basis sets is used in the prediction of geometries & energetics associated with the dissociation of terminal R–X bond present in the unimer, dimer & trimer. The relative equilibrium constant (K ATRP) for the ATRP activation/deactivation steps is calculated from the free energy values associated with dissociation of R–X bond. The relative K ATRP values of dimer & trimer of selected monomers is compared with their respective unimer. From the transition state geometries of the dimeric propagating radical, activation energy is calculated. The gas phase rate coefficients for propagation (k p) (of itaconimides & MMA copolymerization) are calculated using the standard transition state theory. The effect of system parameters such as solvent, temperature & substituent on K ATRP & k p values of dimer is investigated systematically. The change in the initiating system & temperature has significant effect on k p values as compared to solvent & various substituent. The K ATRP values of dimer & trimer dormant species are higher as compared to their respective monomeric species. The neighboring monomer & penultimate monomer plays vital role in kinetics & thermodynamics associated with copolymerization. The obtained initial results show that the mechanism of copolymerization of itaconimide monomers & MMA follows penultimate model.

Gelation in Photoinduced ATRP with Tuned Dispersity of the Primary Chains

We investigated gelation in photoinduced atom transfer radical polymerization (ATRP) as a function of Cu catalyst loading and thus primary chain dispersity. Using parallel polymerizations of methyl acrylate with and without the addition of a divinyl crosslinker (1,6-hexanediol diacrylate), the approximate values of molecular weights and dispersities of the primary chains at incipient gelation were obtained. In accordance with the Flory-Stockmayer theory, experimental gelation occurred at gradually lower conversions when the dispersity of the primary chains increased while maintaining a constant monomer/initiator/crosslinker ratio. Theoretical gel points were then calculated using the measured experimental values of dispersity and initiation efficiency. An empirical modification to the Flory-Stockmayer equation for ATRP was implemented, resulting in more accurate predictions of the gel point. Increasing the dispersity of the primary chains was found not to affect the distance between the theoretical and experimental gel points and hence the extent of intramolecular cyclization. Furthermore, the mechanical properties of the networks, such as equilibrium swelling ratio and shear storage modulus showed little variation with catalyst loading and depended primarily on the crosslinking density.

Modelling Development in Radical (Co)Polymerization of Multivinyl Monomers

Radical polymerization (RP) of multivinyl monomers (MVMs) provides a facile solution for manipulating polymer topology and has received increasing attention due to their industrial and academic significance. Continuous efforts have been made to understand their mechanism, which is the key to regulating materials structure. Modelling techniques have become a powerful tool that can provide detailed information on polymerization kinetics which is inaccessible by experiments. Many publications have reported the combination of experiments and modelling for free radical polymerization (FRP) and reversible-deactivation radical polymerizations (RDRP) of MVMs. Herein, a minireview is presented for the most important modelling techniques and their applications in FRP/RDRP of MVMs. This review hopes to illustrate that the combination of modelling and wet experiments can be a great asset to polymer researchers and inspire new thinking for the future MVMs experiment optimization and product design.

PET-RAFT Increases Uniformity in Polymer Networks

Photoinduced electron/energy transfer (PET)-reversible addition-fragmentation chain transfer polymerization (RAFT) and conventional photoinitiated RAFT were used to synthesize polymer networks. In this study, two different metal catalysts, namely, tris[2-phenylpyridinato-C2,N]iridium(III) (Ir(ppy)₃) and zinc tetraphenylporphyrin (ZnTPP), were selected to generate two different catalytic pathways, one with Ir(ppy)₃ proceeding through an energy-transfer pathway and one with ZnTPP proceeding through an electron-transfer pathway. These PET-RAFT systems were contrasted against a conventional photoinitated RAFT process. Mechanically robust materials were generated. Using bulk swelling ratios and degradable cross-linkers, the homogeneity of the networks was evaluated. Especially at high primary chain length and cross-link density, the PET-RAFT systems generated more uniform networks than those made by conventional RAFT, with the electron transfer-based ZnTPP giving superior results to those of Ir(ppy)₃. The ability to deactivate radicals either by RAFT exchange or reversible coupling in PET RAFT was proposed as the mechanism that gave better control in PET-RAFT systems.

Ultrafast Visible-Light-Induced ATRP in Aqueous Media with Carbon Quantum Dots as the Catalyst and Its Application for 3D Printing

Photoinduced atom transfer radical polymerization (ATRP) has been proved to be a versatile technique for polymer network formation. However, the slow polymerization rates of typical ATRP limited its application in the field of additive manufacturing (3D printing). In this work, we introduced carbon quantum dots (CQDs) for the first time to the ATRP in aqueous media and developed an ultrafast visible-light-induced polymerization system. After optimization, the polymerization could achieve a high monomer conversion (>90%) within 1 min, and the polydispersity index (PDI) of the polymer was lower than 1.25. This system was then applied as the first example of ATRP for the 3D printing of hydrogel through digital light processing (DLP), and the printed object exhibited good dimensional accuracy. Additionally, the excellent and stable optical properties of CQDs also provided interesting photoluminescence capabilities to the printed objects. We deduce this ATRP mediated 3D printing process would provide a new platform for the preparation of functional and stimuli-responsive hydrogel materials.

Thermally Degradable Poly(n-butyl acrylate) Model Networks Prepared by PhotoATRP and Radical Trap-Assisted Atom Transfer Radical Coupling

Model poly(n-butyl acrylate) (PBA) networks were prepared by photoinduced atom transfer radical polymerization (photoATRP), followed by curing of polymer stars via atom transfer radical coupling (ATRC) with a nitrosobenzene radical trap. The resulting nitroxyl radical installed thermally labile alkoxyamine functional groups at the junctions of the network. The alkoxyamine crosslinks of the network were degraded back to star-like products upon exposure to temperatures above 135 °C. Characterization of the degraded products via gel permeation chromatography (GPC) confirmed the inversion of polymer topology after thermal treatment.

Open-air green-light-driven ATRP enabled by dual photoredox/copper catalysis

Photoinduced atom transfer radical polymerization (photo-ATRP) has risen to the forefront of modern polymer chemistry as a powerful tool giving access to well-defined materials with complex architecture. However, most photo-ATRP systems can only generate radicals under biocidal UV light and are oxygen-sensitive, hindering their practical use in the synthesis of polymer biohybrids. Herein, inspired by the photoinduced electron transfer-reversible addition–fragmentation chain transfer (PET-RAFT) polymerization, we demonstrate a dual photoredox/copper catalysis that allows open-air ATRP under green light irradiation. Eosin Y was used as an organic photoredox catalyst (PC) in combination with a copper complex (X–Cu^II/L). The role of PC was to trigger and drive the polymerization, while X–Cu^II/L acted as a deactivator, providing a well-controlled polymerization. The excited PC was oxidatively quenched by X–Cu^II/L, generating Cu^I/L activator and PC˙⁺. The ATRP ligand (L) used in excess then reduced the PC˙⁺, closing the photocatalytic cycle. The continuous reduction of X–Cu^II/L back to Cu^I/L by excited PC provided high oxygen tolerance. As a result, a well-controlled and rapid ATRP could proceed even in an open vessel despite continuous oxygen diffusion. This method allowed the synthesis of polymers with narrow molecular weight distributions and controlled molecular weights using Cu catalyst and PC at ppm levels in both aqueous and organic media. A detailed comparison of photo-ATRP with PET-RAFT polymerization revealed the superiority of dual photoredox/copper catalysis under biologically relevant conditions. The kinetic studies and fluorescence measurements indicated that in the absence of the X–Cu^II/L complex, green light irradiation caused faster photobleaching of eosin Y, leading to inhibition of PET-RAFT polymerization. Importantly, PET-RAFT polymerizations showed significantly higher dispersity values (1.14 ≤ Đ ≤ 4.01) in contrast to photo-ATRP (1.15 ≤ Đ ≤ 1.22) under identical conditions.

Fully oxygen-tolerant photoinduced atom transfer radical polymerization (photo-ATRP) allowed the synthesis of well-defined polymers using a Cu catalyst and eosin Y at ppm levels in both aqueous and organic media.

Living Polymer Networks Prepared by Controlled Radical Polymerization Techniques

Controlled radical polymerization (CRP) techniques have become widely accepted and used in polymer research and development. While much has been done towards their traditional usage in linear and branched systems,...

Nanoengineering with RAFT polymers: from nanocomposite design to applications

Reversible addition–fragmentation chain-transfer (RAFT) polymerization is a powerful tool for the precise formation of macromolecular building blocks that can be used for the construction of well-defined nanocomposites.