Conventional Polymerization Research Articles

Scalable Synthesis and Characterization of Multilayer γ-Graphyne, New Carbon Crystals with a Small Direct Band Gap.

γ-Graphyne is the most symmetric sp2/sp1 allotrope of carbon, which can be viewed as graphene uniformly expanded through the insertion of two-carbon acetylenic units between all the aromatic rings. To date, synthesis of bulk γ-graphyne has remained a challenge. We here report the synthesis of multilayer γ-graphyne through crystallization-assisted irreversible cross-coupling polymerization. A comprehensive characterization of this new carbon phase is described, including synchrotron powder X-ray diffraction, electron diffraction, lateral force microscopy, Raman spectroscopy, infrared spectroscopy, and cyclic voltammetry. Experiments indicate that γ-graphyne is a 0.48 eV band gap semiconductor, with a hexagonal a-axis spacing of 6.88 Å and an interlayer spacing of 3.48 Å, which is consistent with theoretical predictions. The observed crystal structure has an aperiodic sheet stacking. The material is thermally stable up to 240 °C but undergoes transformation at higher temperatures. While conventional 2D polymerization and reticular chemistry rely on error correction through reversibility, we demonstrate that a periodic covalent lattice can be synthesized under purely kinetic control. The reported methodology is scalable and inspires extension to other allotropes of the graphyne family.

Recent Concepts for Supramolecular 2D Materials

Bottom-up approaches are one strategy geared towards designing novel two-dimensional materials. Supramolecular polymerization has proven to be an effective way of obtaining these architectures due to the increasing control and tunability offered by different functional groups, which are not afforded by conventional polymerization. In this short review, we highlight examples of supramolecular assemblies held together by well-known non-covalent interactions, as well as new approaches that are becoming more relevant in recent years.

Systematic study on interfacial polymerization mechanism of toluene diisocyanate and water for the preparation of polyurea microspheres

• Droplets-based microfluidics is used to generate TDI droplets in aqueous phase. • Polyurea microspheres were prepared by interface polymerization of TDI with water. • Interface polymerization mechanism of TDI with water is studied in details. Polyureas (PU) are important materials in wide range of applications from protective coatings and catalyst supports to biomaterials for drug release and hydrogels. However, it has been a challenging task to prepare porous PU with definite form or shape limited by the nature of the PU synthesis, that is, precipitation polymerization. New chemical and physical techniques of PU synthesis have gained great attention in order to fabricate these materials with diverse morphologies and structural features. In this communication, droplet-based microfluidics approach is adopted to convert conventional precipitation polymerization of PU synthesis to interface polymerization and PU microspheres with porous morphology are prepared. In this process, first toluene diisocyanate (TDI) droplets were generated in flowing PVA aqueous solution inside a tube and then converted to uniform porous PU microspheres through interface polymerization. The interface polymerization mechanism is discussed in details by controlling the polymerization time. It was found that polymerization of TDI with water was started at the interface of TDI droplet and water, and PU shell was formed around the TDI droplets, leading to formation of microcapsules. After the formation of PU shell, polymerization was continued inside the microcapsule by the diffusion of water molecules through the PU shell until all the TDI was finished and PU microspheres with porous morphology were obtained. This communication provides therefore a systematic study on interfacial polymerization of TDI with water to get porous PU microspheres and enabling technical advantages for potential applications to get PU materials with specific shapes and textural modifications.

Improving PDLC electro-optical performance using a photomask multi-step polymerisation method

ABSTRACT Polymer-dispersed liquid crystals (PDLCs) have been intensively studied for their light scattering properties and are of great use in electro-optical display devices. In this paper, high performance PDLCs were prepared by a multi-step polymerisation method using a photomask through a polymerisation-induced phase separation (PIPS) process. The effect of the photomask on the polymerisation of polymerisable monomers was investigated and it was confirmed that the photomask could effectively polymerise the polymerisable monomers in the light-transmitting fraction preferentially to form polymer-dominated spacer columns. In the subsequent complementary polymerisation process, the liquid crystal content of the previously unpolymerised fraction increases, which leads to a decrease in threshold and drive voltage and an increase in contrast of the PDLC film. Compared to conventional polymerisation methods, the multi-step polymerisation method can reduce the threshold voltage to 38.5 V, the drive voltage to 55.8 V and the contrast to 42, which greatly improves the overall electro-optical properties of PDLC, and the formation of spacer columns improves the bonding of the film, offering new possibilities for achieving energy efficient PDLC films and flexible films.

Structurally-unique polymeric materials obtained through catalytic post-polymerization protocols

Polyolefins are organic polymers of great importance in everyday life, however, the lack of functional groups in their structure significantly limits their wider potential use. Therefore, development of efficient protocols based on catalytic or stoichiometric transformations and leading to functionalized polyolefins is a challenge worth taking on. Herein, we present a high-yield synthesis of a novel polymeric precursor containing side ethynylsilyl groups, and their subsequent functionalization through a wide range of transition metal-catalyzed reactions. The transformation of a versatile unsaturated polymeric precursor allowed us to obtain a library of hydrocarbon polymeric materials of unique structures with specific functional moieties, that are otherwise inaccessible, difficult or too expensive to be obtained by conventional polymerization techniques. The demonstrated approach opens new opportunities for the design and synthesis of polymers with properties precisely tailored to the target applications.

Synthesis and Gas Separation Properties of Aromatic Polyimides Containing Noncoplanar Rigid Sites

Four aromatic polyimides were prepared using a conventional two-stage polymerization reaction of diamine monomers containing different noncoplanar rigid sites with commercially available dianhydride 6FDA. All polymers displayed high relative molecular masses, excellent solubilities, and outstanding thermal properties with Tg values higher than 260 °C, which ensured that they were able to be casted as dense films for gas permeation measurement. The comprehensive gas transport properties of four prepared polyimides were higher than conventional aromatic polyimides (e.g., Matrimid 5218 and Kapton), which suggested that the incorporation of the noncoplanar rigid groups into the polymer main chain was beneficial to prevent segment packing as well as to enhance the gas separation properties. The pure CO2 permeability coefficient of the spirobichroman-based polyimide (6FDA-BDA) was 2.9 times as high as that of Matrimid 5218, without sacrificing selectivity. Moreover, the effect of different noncoplanar rigid sites on the gas separation performance of aromatic polyimides was systematically investigated. By measurements of FFV, density, and d-spacing, it has been observed that the incorporation of different noncoplanar rigid sites significantly affected the microstructure, thus affecting the gas transport. For example, because the polyimide containing pendent phenyl groups (6FDA-BDM) had the lowest FFV and the densest segment packing, it exhibited the lowest permeability. Hence, the basic insights to the structure/property relationships of the four polyimides obtained in this work offer a meaningful guide for next-generation gas separation membranes.

Fabrication of positively charged nanofiltration membrane with uniform charge distribution by reversed interfacial polymerization for Mg2+/Li+ separation

Nanofiltration is considered a promising technology for separation of multivalent/monovalent ions such as extracting lithium from Salt Lake brine with high Mg2+/Li+ ratio. However, the nanofiltration membranes fabricated via conventional interfacial polymerization process generally possess negatively charged surface and have low Mg2+/Li+ selectivity. Herein, we proposed a new and facile method, i.e., reversed interfacial polymerization (RIP), to prepare nanofiltration membranes with positively charged surface and uniform charge distribution. The sequence of amine (polyethyleneimine, PEI) and acyl chloride (trimesoyl chloride, TMC) monomers on polysulfone support was reversed compared to the conventional interfacial polymerization (IP) process. Moreover, the solvent of amine monomer was acetone instead of water. The nanofiltration membranes fabricated by this method exhibited higher water flux (from 4.88 to 22.25 Lm−2h−1) and MgCl2 rejection (from 84.36% to 97.71%). Meanwhile, LiCl/MgCl2 separation factor in single salt solution reached up to 13.93, which was almost quadruple compared to the conventional control membrane. In addition, the developed nanofiltration membrane also exhibited an excellent separation selectivity (SLi, Mg = 9.22) in mixture system (Mg2+/Li+ mass ratio of 20), which had good application potential in extracting lithium resources from Salt Lake brine.

Metal-assisted multiple-crosslinked thin film composite hollow fiber membrane for highly efficient bioethanol purification

Polyamide (PA)-based thin film composite (TFC) membranes have been extensively applied in various membrane-based separations. However, research works for bioethanol purification are relatively limited due to insufficient hydrophilicity and chain packing density of the PA selective layer by conventional interfacial polymerization. In this work, a new TFC hollow fiber (HF) membrane is fabricated by metal-assisted multiple crosslinking strategy, that is, metal-coordinated crosslinking of the pristine PA layer and coordination complexation between metal ions and phytic acid (PhA) for advanced water/ethanol separation. By tuning coordination abilities of metal ions with PA and PhA and the cycle number of PhA/metal ion assembly, PA-based TFC HF membrane is perfected. Additionally, a joint experiment/simulation characterization is deployed to reveal the coordination abilities of various metal ions with the pristine PA and grafted PhA. Ultimately, the synergistic effect between PA layer and PhA-metal ion complexes (i.e., 1 + 1 > 2 effect) is embodied in the separation performance of water/ethanol separation. The resulting TFC-Fe3+-PhA membrane with the strongest PhA-metal ion coordination ability exhibits the best water/ethanol separation performance, i.e., the separation factor of 1703 (34 times higher than pristine PA TFC HF membrane) and total flux of 1705 g/m2 h. This metal-assisted multiple crosslinking strategy is therefore believed to shed important lights on the development of next-generation high-performance TFC membranes for bioethanol purification.

Effect of surfactant concentration and monomer polarity on particle nucleation in emulsion step polymerization of dithiol with diene

The dependence of the number of particles Np as a function of the surfactant concentration [S] is investigated for the step polymerization of dithiol-diene emulsions. A sigmoidal curve for log Np vs log [S] is found for a range of monomers regardless of their polarity. Above the critical micellar concentration (6–20 mM), a Np ∝ [S]x relationship is established with an exponent x dependent on the polarity of the two co-monomers. When the two co-monomers are highly water insoluble, x varies typically between 0.6 and 1. With two relatively water soluble co-monomers, x is close to 0. When two co-monomers with contrasting water solubility are involved, the power dependence is more difficult to predict and ranges from 0 to 1, but high x value are generally found when one of the two monomers is highly hydrophobic. This overall trend can be reconciled with the behavior of a conventional emulsion radical chain polymerization. Graphical abstract

Chemical initiator-free synthesis of Poly (acrylic acid-co-itaconic acid) using radiation-induced polymerization for application in dental cements

Glass ionomer cements (GICs) have been explored by the researchers around the world for their applications in dentistry because of numerous advantages such as their distinctive clinical properties e.g., anticariogenic properties, chemical adhesion to tooth surface and biocompatibility. However, the GICs prepared through the conventional chemical polymerization methods suffer from many disadvantages including release of unreacted monomer and toxic initiator into oral cavity. Therefore, in the present work, attempts were made to synthesize the polymer to be used in GICs using toxic initiator-free γ-irradiation technique. Different molar ratios of acrylic acid and itaconic acid were polymerized using Co-60 γ-source to produce Poly(acrylic acid-co-itaconic acid, PAA-co-IA). The synthesized copolymers, were characterized by FTIR, DSC and TGA. Compressive strengths of GIC specimens formed by incorporating fluoro-aluminosilicate (FAS) glass with synthesized copolymers, were investigated after storing for 1, 7, 14 and 28 days in distilled water. FESEM was performed to study the surface morphology of the cements. The working and setting time were determined as per ISO4049. The copolymers PAA-co-IA were synthesized via γ-irradiation method to form GIC. The results show that DC/PAA-co-IA/2:1 have higher Compressive Strength (CS) of 157.65 ± 4.02 M Pa as compared to control. High acidic erosion stability was observed, which was in agreement with the FESEM studies showing lower cracks and voids. Thus, γ-irradiation polymerization technique was initiator-free, facile and proficient for the synthesis of copolymers used in preparing GICs.

Can the NF membrane directly obtained by the interfacial polymerization of MPD and TMC?

In the practical application of nanofiltration (NF) membrane, regular chemical cleaning is necessary to eliminate the membrane fouling and ensure the normal operation of the system. Generally, the commercial NF membranes can be divided into MPD-TMC membranes and PIP-TMC membranes of which the permeability and pH resistance cannot be balanced. In this work, the ultra-low concentration monomers of MPD and TMC were used to fabricate the dense polyamide layer of NF membrane through a conventional interfacial polymerization reaction. The newly prepared membrane exhibited a smooth surface with very low roughness. Besides, the pore size distribution and desalination performance including water permeability and salt rejection of our membrane were comparable to the lab-made and commercial PIP-TMC membranes. The membrane was also confirmed to have an excellent separation efficiency to SO42−/Cl− anions and good resistance to extreme pH conditions. Overall, this study presents a new insight for the preparation of high-performance NF membrane with good chemical stability.

Vapor-phase polymerization of fibrous PEDOT on carbon fibers film for fast pseudocapacitive energy storage

Poly(3,4-ethylenedioxythiophene) (PEDOT) has emerged as one of promising conductive polymers in energy storage devices. However, the conventional solution oxidative polymerization usually produces PEDOT with low conductivity and limited surface area. This work reports the preparation of highly conductive fibrous PEDOT by a vapor-phase polymerization initialized with Fe2O3 nanosheets that are uniformly electrochemically deposited on the N-doped carbon nanofibers (CNFs) film. The incorporation of highly conductive PEDOT nanofibers expands the film and simultaneously increase the film conductivity by 80 times (103 S cm−1). Accordingly, an areal capacitance of 1926 mF cm−2 at 5 mA cm−2 with a PEDOT mass loading of 8.68 mg cm−2 has been achieved. Importantly, the fast pseudocapacitive charge storage mechanism afford the CNF-PEDOT a high-rate capability which retains 68% capacitance in 5–50 mA cm−2. Especially, the CNF-PEDOT film electrode exhibits an outstanding stability with 87% capacitance retention after 10,000 consecutive charging and discharging cycles at 50 mA cm−2. A CNF-PEDOT-based supercapacitor delivers an energy density of 97 μWh cm−2 at power density of 0.45 mW cm−2, surpassing state-of-the-art PEDOT-based devices. This work will open a new avenue for preparing highly conductive PEDOT hybrid electrodes towards high-performance supercapacitors.

Facile access to ultra-highly branched polyethylenes using hybrid “sandwich” Ni(II) and Pd(II) catalysts

The branching type and amount in polyolefins have a significant impact on the material properties. In this study, a family of “sandwich” or “semi-sandwich” α-diimine ligands with unilateral steric hindrance and the corresponding Ni(II) and Pd(II) complexes have been designed and synthesized. In the nickel-catalyzed ethylene polymerization, the developed Ni(II) catalysts exhibited moderate activities and yielded highly branched polyethylenes with high molecular weights (up to 473.2 kg/mol). Unexpectedly, the hybrid “sandwich” Ni(II) catalyst bearing 8-aryl- and 2-dibenzosuberyl-naphthyl fragments generated ultra-highly branched (146–168/1000C) polyethylene with a unique branching distribution pattern under conventional polymerization conditions. More uniquely, the branching density of the obtained polyethylene decreased gradually with increasing temperature, contrary to the previous literature reports. In the palladium-catalyzed ethylene polymerization, the Pd(II) catalysts displayed moderate activities and yielded hyperbranched polyethylenes with high molecular weights (up to 191 kg/mol). Similar to the nickel-catalyzed ethylene polymerization, the hybrid “sandwich” Pd(II) catalyst also yielded polyethylenes with higher branching densities (112–118 vs 88–95/1000C) and molecular weights (101–191 vs 59–130 kg/mol) than the corresponding “semi-sandwich” Pd(II) catalysts. Moreover, the hybrid “sandwich” Pd(II) catalyst generated E-MA copolymers with the highest branching densities and incorporation ratios among the catalysts. Overall, the hybrid sandwich structure facilitates the synthesis of higher branched polyethylene in the Ni(II) and Pd(II) catalyzed ethylene (co)polymerization reactions.

Preparation of One-Dimensional Polyaniline Nanotubes as Anticorrosion Coatings.

Uniform polyaniline (PANI) nanotubes were synthesized by a self-assembly method under relatively dilute hydrochloric acid (HCl) solution. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and UV-Vis-NIR spectroscopy were employed to characterize the morphology and molecular structure of the PANI products. SEM images show that the PANI nanotubes have uniform morphology and form compact coating on the substrate surface. For comparison, aggregated PANI was also synthesized by conventional polymerization method. The performance of the PANI products on carbon steel was studied using eletrochemical measurement and immersion corrosion experiment in 3.5 wt% NaCl aqueous solution. The corrosion potentials of carbon steel samples increase by 0.196 V and 0.060 V after coated with PANI nanotubes and aggregated PANI, respectively, and the corrosion currents density decrease by about 76.32% and 36.64%, respectively. The 6-day immersion experiment showed that the carbon steel samples coated by PANI nanotubes showed more excellent anticorrosion performance, because the more compact coating formed by PANI nanotubes may inhibit the corrosion process between the anodic and cathodic.

Circular Discovery in Small Molecule and Conjugated Polymer Synthetic Methodology.

Simple and efficient methods are a key consideration for small molecule and polymer syntheses. Direct arylation polymerization (DArP) is of increasing interest for preparing conjugated polymers as an effective approach compared to conventional cross-coupling polymerizations. As DArP sees broader utilization, advancements are needed to access materials with improved properties and different monomer structures and to improve the scalability of conjugated polymer synthesis. Presented herein are considerations for developing new methods of conjugated polymer synthesis from small molecule transformations, exploring how DArP has successfully used this approach, and presenting how emerging polymerization methodologies are developing similarly. While it is common to adapt small molecule methods to polymerizations, we demonstrate the ways in which information gained from studying polymerizations can inform and inspire greater advancements in small molecule transformations. This circular approach to organic synthetic method development underlines the value of collaboration between small molecule and polymer-based synthetic research groups.

Ultrasonication-induced and diluent-assisted suspension polymerization for size-controllable synthesis of polydimethylsiloxane droplets

Submicroscale polydimethylsiloxane (PDMS) spheres are emerging as a promising solution for a variety of engineering applications due to their unique material properties and size. It is, however, still considered as challenging to produce submicroscale PDMS droplets. This leads to the need for development of a deterministic method for producing size-controllable, monodisperse PDMS droplets and, by extension, comprehensive understanding of the physicochemical players and processes involved in the synthesis method. Here, we develop an ultrasonication-induced and diluent-assisted (UIDA) suspension polymerization process to achieve the scalable synthesis of monodisperse PDMS droplets. The UIDA suspension polymerization process is essentially the same as conventional suspension polymerization processes except ultrasonic agitation and organic diluent addition. The use of ultrasonication is intended to controllably reduce the size of PDMS droplets, while the addition of a diluent to PDMS is designed to enhance the monodispersity of PDMS droplets (major) and decrease their size (minor). First, we explore the dependence of PDMS droplet size and polydispersity on rudimentary factors such as stabilizer (i.e., polyvinyl alcohol (PVA)), magnetic stirring, ultrasonication, diluent (i.e., benzene), and synthesis vessel. Next, a time-variant change in the size and size distribution of PDMS droplets under UIDA suspension polymerization process are investigated by deconvoluting the droplet dispersity in size into two components, each of which is described using an envelope of the log-normal distribution. The main cause of a bimodal distribution is also identified. Finally, we demonstrate the applicability of PDMS droplets in altering the hydrodynamic properties of polymer surfaces by fabricating a set of rose petal-inspired substrates through evaporation coating of PDMS droplets on flat PDMS surfaces. The findings of this study will lead to better understanding of suspension polymerization for synthesizing monodisperse submicroscale droplets made of thermosetting polymers.

Stereochemistry-Induced Discrimination in Reaction Kinetics of Photo-RAFT Initialization

Photoinduced reversible addition–fragmentation chain transfer (photo-RAFT) polymerization combines conventional RAFT polymerization with photochemistry, in which the carbon radicals (R radicals) are generated from RAFT agents (except the cases using external radical photoinitiators) by direct photolysis or photoredox catalysis. As one of the key components, RAFT agent is responsible for living control of photo-RAFT polymerization and various reaction kinetics in the processes of activation/deactivation, propagation, and termination. Despite considerable efforts having been devoted to investigating structural effect of RAFT agents on polymerization kinetics, the impact of stereochemistry in RAFT agents is still underexplored. In this article, we presented a significant stereochemical effect of initial RAFT agents on the kinetics of a photo-RAFT polymerization during the initialization period (the period of consumption of initial RAFT agent). Specifically, two diastereomeric RAFT agents were synthesized and employed for photo-RAFT polymerization. Under a condition of low monomer/RAFT agent ratio, we observed distinct consumption rates of two RAFT agents in separated polymerization systems, with one diastereomer faster than the other. A similar result was observed in the mixed polymerization system (a 1:1 mixture of two diastereomeric RAFT agents), demonstrating a discrimination in RAFT agent consumption in spite of the presence of RAFT chain transfer. Additionally, this discrimination was also present in thermally initiated RAFT polymerization, whereas an opposite trend was observed in the separated systems. The kinetics of initialization processes was analyzed with the aid of density functional theory calculations, which provided plausible explanation of such discrimination. The reported stereochemical effect applies to long dormant RAFT polymer chains beyond the initialization period, in which different stereochemical R groups are always present over the course of RAFT polymerization.

ZIF-67 templated thin-film composite forward osmosis membrane: Importance of incorporation method on morphology and performance

In this study, a promising strategy is reported to synthesize a high water-permeable polyamide (PA) rejection layer using ZIF-67 nanoparticle as a sacrificial templating material. ZIF-67 nanoparticle was incorporated into the PA rejection layer using two different strategies (i) conventional blending interfacial polymerization (IP) and (ii) newly introduced in-situ growth methods. The primary aim was to study the effects of various incorporation strategies on template removal efficiency. In the conventional blending IP method, the pre-synthesized ZIF-67 nanoparticle was dispersed in the amine monomer solution and incorporated into the PA layer of thin-film composite membranes (TFN-ZIF-PS, modified with pre-synthesized ZIF-67). But in the in-situ method, ZIF-67 was synthesized and incorporated simultaneously with the formation of the PA layer via interfacial reaction of aqueous amine/Co+2 and organic acid chloride/Hmim solutions (TFN-ZIF-IS, modified with in-situ synthesized ZIF-67). After IP reaction, ZIF-67 nanoparticles were removed by water dissolution, which created nanovoids within the PA layer. Systematic membrane characterization confirmed that the incorporation method significantly affects template removal efficiency, where the TFN-ZIF-IS membrane shows a quite different morphology after ZIF-67 removal (membrane with nanovoids (NV), TFC-NV-IS). The effective incorporation and removal of ZIF-67 nanoparticles increased the water permeability of TFC-NV-IS to 5.6 LMH/bar, which is about 5-fold compared with the control TFC membrane. Additionally, TFC-NV-IS exhibited forward osmosis water flux that was raised about 2-fold compared with the control TFC one with a negligible decrease in selectivity. These considerably enhanced separation performances can be attributed to the improved water transport through the as-formed nanovoids. Thus, our strategies (incorporation and template removal) in this study provide a new avenue to synthesize advanced TFC-FO membranes with exceptional performance.

Amphiphilic polymeric photoinitiator composed of PEG-b-PCL diblock copolymer for three-dimensional printing of hydrogels

Herein, poly(ethylene glycol)-block-poly(ɛ-caprolactone) (PEG114-b-PCLx) copolymer is employed to enhance the water solubility of fashionable photoinitiator, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO). PEG114-b-PCLx copolymers are first polymerized via the conventional ring-opening polymerization. Subsequently, TPO encapsulated nanoparticles (TPO@PEG114-b-PCLx) are prepared through the nanoprecipitation method, followed by a water removal process using lyophilization. By altering the PEG114-b-PCLx molecular weights and TPO: PEG114-b-PCLx ratios, the resulting nanoparticles exhibited hydrodynamic average sizes ranging from 190 to 360 d.nm with the TPO encapsulation efficiency of approximately 21–35%. Afterward, these prepared photoinitiators were formulated with poly(ethylene glycol dimethacrylate) (PEGDMA) and methacrylate-functionalized dextran (Dex-MA) before fabricating the 3D-printed hydrogels through digital light processing (DLP). The compressive moduli of the hydrogels covered from 0.13 to 1.79 MPa, depending on the content of PEGDMA and Dex-MA and the degree of substitution of Dex-MA. The cytotoxicity results of printed specimens revealed that the hydrogels are noncytotoxic to chondrocyte and fibroblast.

Preparation of well-defined Poly(Vinyl alcohol) by hydrolysis of Poly(Vinyl acetate) synthesized by RAFT suspension polymerization

Poly(vinyl alcohol) (PVA) is a widely used synthetic polymer that is made by hydrolysis of poly(vinyl acetate) (PVAc). A significant challenge in the production of well-defined PVA arises due to the high frequency of chain transfer reactions that occur in the radical polymerization of PVAc, which limits the molecular weight and leads to branching. Upon hydrolysis of PVAc, both acetate groups and branch points can be hydrolyzed, resulting in a PVA with a significantly lower molecular weight than the parent PVAc, making control over the molecular weight distribution of PVA difficult. In this work we demonstrate the production of PVAc with a well-defined and linear structure by reversible addition-fragmentation chain transfer (RAFT) polymerization under conditions in which chain transfer is reduced. PVAc samples were prepared by suspension polymerization using both conventional free-radical polymerization and RAFT polymerization at 50 °C. When using RAFT polymerization, upon hydrolysis there was a minimal decrease of the degree of polymerization and high molecular weight PVA of low dispersity was obtained. These results demonstrate the synthesis of well-defined PVA and offers a potential route to the production of PVAc and PVA products with uniform properties.