Reversible Addition-fragmentation Chain Transfer Copolymerization Research Articles

Kinetics of RAFT polymerization and copolymerization of vinyl monomers by size exclusion chromatography

New method to study kinetics of homo- and copolymerization of vinyl monomers based on size exclusion chromatography (SEC) was developed. The use of this method is associated with some special requirements like identity of an eluent for SEC and the solvent for polymerization, and possessing refractive index increments dn/dc of a monomer and corresponding polymer. Monomer conversion was calculated by comparing intensity of the signals in SEC elution curves attributed to a monomer and corresponding polymer, and taking into account differences in their dn/dc values. The developed method is also applicable to study kinetics of copolymerization including evolution of copolymer composition if one of the monomers is a macromonomer (possess relatively high molecular weight). Suitability of the proposed method was demonstrated by studying kinetics of Reversible Addition Fragmentation Chain Transfer (RAFT) polymerization and copolymerization of 2-hydroxyethyl methacrylate (HEMA) and two poly(ethylene oxide) monomethyl ether methacrylates (PEO5MEMA and PEO9MEMA). It was shown that the new method has some advantages over the other methods used to study kinetics of polymerization (e.g., 1H NMR spectroscopy), since, in the case of SEC with triple detection, it not only enables to calculate monomer conversion and polymerization rate, but simultaneously provides comprehensive information about polymer characteristics (Mn, Mw, Mw/Mn, copolymer composition, etc.) and development of these characteristics during (co)polymerization. It was determined that the synthesized copolymers of HEMA and PEO9MEMA were characterized by low dispersity and gradient distribution of the monomeric units.

Effects of alkyl group size on the structure and dynamics of poly(n-alkyl methacrylate)-based ionomers

The effects of alkyl group size on the structure and dynamics of poly(n-alkyl methacrylate)-based ionomers were investigated in this study. Ionomer samples were synthesized via the reversible addition–fragmentation chain transfer copolymerization of sodium styrene sulfonate and alkyl methacrylate with different alkyl groups (methyl, butyl, hexyl, lauryl, and octodecyl groups) and with varying ion contents. The samples were characterized by dielectric response spectroscopy (DRS), X-ray scattering, and linear viscoelasticity (LVE) measurements. X-ray scattering revealed ionic peaks indicative of spacing between ion aggregates. The interaggregate spacing decreased with increasing ion content when the alkyl groups were methyl, butyl, or hexyl groups. This observation is in accordance with the trend reported for sulfonated polystyrene, which has been extensively studied. In contrast, the interaggregate correlation peak merged with the backbone correlation peak when the alkyl groups were lauryl or octodecyl groups, suggesting that the steric repulsion of the long side chains partly suppressed the interchain association. Quantitative analysis of LVE showed that the sol-to-gel transition occurred at a higher number of ions per chain for samples with longer alkyl groups, lending support to the idea that long side chains generated increased steric repulsion. In addition, the plateau region broadened gradually with increasing alkyl group size, reflecting an increase in electrostatic interaction energy among the ionic groups. This increase was attributed to a reduction in the polarity of the polymer medium as the size of the nonpolar alkyl group increased, as detected by DRS.The effects of alkyl group size on the structure and dynamics of poly(n-alkyl methacrylate)-based ionomers were investigated in this study. Ionomer samples were synthesized via the reversible addition–fragmentation chain transfer copolymerization of sodium styrene sulfonate and alkyl methacrylate with different alkyl groups (methyl, butyl, hexyl, lauryl, and octodecyl groups) and with varying ion contents. The samples were characterized by dielectric response spectroscopy (DRS), X-ray scattering, and linear viscoelasticity (LVE) measurements. X-ray scattering revealed ionic peaks indicative of spacing between ion aggregates. The interaggregate spacing decreased with increasing ion content when the alkyl groups were methyl, butyl, or hexyl groups. This observation is in accordance with the trend reported for sulfonated polystyrene, which has been extensively studied. In contrast, the interaggregate correlation peak merged with the backbone correlation peak when the alkyl groups were lauryl or octodecyl gro...

Preparation of an amphiphilic diblock copolymer composed of polystyrene and hydrophilic alternating copolymer blocks

Generally, conventional free-radical polymerization of an allyl monomer affords low-molecular-weight oligomers. However, since the allyl monomer can form a charge transfer complex with maleic anhydride (MA), in which the former acts as an electron donor and the latter acts as an acceptor, relatively high-molecular-weight alternating copolymers can be obtained via copolymerization of an allyl monomer and MA. In this study, hydrophilic alternating copolymers (P(11EO/MA)m) of methoxy poly(ethylene glycol) allyl ether (11EO) and MA were prepared via reversible addition–fragmentation chain transfer (RAFT)-controlled radical polymerization. The alternating nature of the polymers was confirmed by the consumption of both monomers during polymerization. The MA units in P(11EO/MA)m were hydrolyzed to prepare pendant carboxylic acid group-containing polymers (P(11EO/MH)m). Furthermore, an amphiphilic diblock copolymer (P(11EO/MH)m-PSn) was prepared via RAFT copolymerization of styrene monomer using P(11EO/MH)m as a macro-chain transfer agent. The association behavior of P(11EO/MH)m-PSn in water was also investigated. Hydrophilic alternating copolymers (P(11EO/MA)m) of methoxy poly(ethylene glycol) allyl ether (11EO) and maleic anhydride (MA) were prepared via controlled radical polymerization. The MA units in P(11EO/MA)m were hydrolyzed to prepare pendant carboxylic acid group-containing polymers (P(11EO/MH)m). Furthermore, an amphiphilic diblock copolymer (P(11EO/MH)m-PSn) was prepared via block copolymerization of styrene using P(11EO/MH)m as a macro-chain transfer agent. The association behavior of P(11EO/MH)m-PSn in water was also investigated.

Semiautomated Parallel RAFT Copolymerization of Isoprene with Glycidyl Methacrylate.

Copolymerization of isoprene (IP) with glycidyl methacrylate (GMA) was performed under RAFT (reversible addition-fragmentation chain-transfer) polymerization conditions in a platform for high-output experimentation. Covering the range between 1 and 0.2 molar fraction of IP in the feed, four sets of reactions were carried out at 10, 15, 20, and 30 h at 115 °C. The kinetic data obtained were used to estimate the reactivity ratios using a nonlinear least-squares approach (NLLS). Reactivity ratios rGMA = 0.61 and rIP = 0.74 indicate that both monomers tend to crosspropagate in agreement with known literature values. Concerning the RAFT study, relatively good control and livingness of the copolymerization was observed except for the experiment in which IP represents 20 mol % in the feed. 1H NMR characterization confirmed the presence of both monomers in the final copolymer, particularly the presence of the epoxy ring of GMA which is susceptible to post polymerization reactions. Finally, preliminary results on the hydrogenation of various polymers are discussed.

Fabrication of novel magnetic graphene oxide nanocomposites for selective adsorption of mercury from aqueous solutions.

In this work, a novel functionalized graphene oxide (GO) was used as an effective and selective adsorbent for removal of mercury (Hg2+). The magnetic nanocomposite adsorbent (MNA) based on GO was prepared through surface reversible addition-fragmentation chain transfer copolymerization of acrylic monomers and then the formation of Fe3O4 nanoparticles. The structure of MNAs was characterized by using FTIR, SEM, TEM, VSM, XRD, and nitrogen adsorption/desorption isotherms. The results of ion adsorption of MNAs demonstrated high selectivity and adsorption efficiency for Hg2+ in the presence of competing ions. Furthermore, the removal of Hg2+ obeyed a pseudo-second-order model and fitted well to the Langmuir isotherm model with the maximum Hg2+ uptake of 389 mg g-1. The MNA was also confirmed as good materials for re-use and maintained 86% of its initial adsorption capacity for mercury after the fifth regeneration cycles. Finally, the experimental results demonstrated that the solution pH, ion concentration, and temperature had a major impact on Hg(II) adsorption capacity. The results indicate that the MNAs with high adsorption abilities could be very promising adsorbents for the selective recovery of ions in wastewater treatment process. Graphical abstract.

Photocleavable Peptide-Poly(2-hydroxyethyl methacrylate) Hybrid Graft Copolymer via Postpolymerization Modification by Click Chemistry To Modulate the Cell Affinities of 2D and 3D Materials.

Controlling the surface properties of engineered materials to enhance or reduce their cellular affinities remains a significant challenge in the field of biomaterials. We describe a universal technique for modulating the cytocompatibilities of two-dimensional (2D) and three-dimensional (3D) materials using a novel photocleavable peptide-grafted poly(2-hydroxyethyl methacrylate) (PHEMA) hybrid. The reversible addition-fragmentation chain transfer copolymerization of HEMA and propargyl acrylate was successfully controlled. The resultant alkyne-containing PHEMA was then used to modify the azide-terminated oligopeptides [Arg-Gly-Asp-Ser (RGDS)] with a photolabile 3-amino-3-(2-nitrophenyl)propanoic acid moiety via the copper-catalyzed alkyne-azide click chemistry. This strategy was readily used to decorate the surfaces of both hydrophilic and hydrophobic materials with RGDS peptides due to the high film-forming abilities of the PHEMA unit. The resultant thin film acted as an effective scaffold for improving cell adhesion and growth of NIH/3T3 fibroblasts and MC3T3-E1 osteoblast-like cells in vitro. In addition, UV irradiation of the surface led to the detachment of cells from the material surface accompanied by the photocleavage of RGDS grafts and enabled the 2D-patterning of cells and cell sheet engineering. The applicability of this system to 3D materials was investigated, and the cell adhesion was remarkably enhanced on a 3D-printed poly(lactic acid) object. This facile, biocompatible, and photoprocessable peptide-vinyl polymer hybrid system is valuable for its ability to advance the fields of tissue engineering, cell chips, and regenerative medicine.

Miniemulsion RAFT Copolymerization of MMA with Acrylic Acid and Methacrylic Acid and Bioconjugation with BSA.

Polymerization through reversible addition-fragmentation chain-transfer (RAFT) polymerization has been extensively employed for the production of polymers with controlled molar mass, complex architectures and copolymer composition distributions intended for biomedical and pharmaceutical applications. In the present work, RAFT miniemulsion copolymerizations of methyl methacrylate with acrylic acid and methacrylic acid were conducted to prepare hydrophilic polymer nanoparticles and compare cell uptake results after bioconjugation with bovine serum albumin (BSA), used as a model biomolecule. Obtained results indicate that the RAFT agent 2-cyano-propyl-dithiobenzoate allowed for successful free radical controlled methyl methacrylate copolymerizations and performed better when methacrylic acid was used as comonomer. Results also indicate that poly(methyl methacrylate-co-methacrylic acid) nanoparticles prepared by RAFT copolymerization and bioconjugated with BSA were exceptionally well accepted by cells, when compared to the other produced polymer nanoparticles because cellular uptake levels were much higher for particles prepared in presence of methacrylic acid, which can probably be associated to its high hydrophilicity.

New strategy of improving the dispersibility of acrylamide-functionalized graphene oxide in aqueous solution by RAFT copolymerization of acrylamide and acrylic acid

Graphene Oxide (GO) is a very unique material with a broad potential. However, modifying GO effectively to achieve maximum dispersion stability in a medium is very critical for various applications. In this paper, GO/poly(acrylamide-co-acrylic acid) (PAM-co-PAA) composites (GMAs) were readily prepared by a two-step method. Firstly, acrylamide (AM) monomer was immobilized onto GO sheets through an amidation reaction, followed by copolymerization of acrylamide (AM) and acrylic acid (AA) on the surface of GO sheets in a second step via reversible addition-fragmentation chain transfer (RAFT) polymerization, GO-AM (GM) acting as a macro monomer to participate in the copolymerization. Characterization by Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) provided evidence for the successful polymerization of AM/AA on the surface of GM. Thermogravimetric analysis (TGA) revealed greater than 50 wt% grafting of PAM-co-PAA. X-ray diffraction (XRD) analysis showed that the d-spacing of the GO sheets increased with the introduction of the polymer. The morphological studies were performed by Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscope (TEM), showing that a polymeric layer covered the surface of GO sheets. Compared to the original morphologies of GO sheets, the more disordered structures were attributed to the intercalation of polymer molecules into the spacing of the GO sheets and the reaction of functional groups on the surface of GO sheets. The dispersion stability test demonstrated that the reported facile method could generate GO-polymer hybrid nanomaterials stably dispersed in aqueous solution for more than 15 days, showing a great potential and practical applications for composite coatings.

Controlled synthesis of thermoresponsive polymers derived from l‐Lysine, a biorenewable resource

ABSTRACTRenewable lysine was cyclized to its corresponding α‐amino‐ε‐caprolactam and then underwent the reaction with acryloyl chloride to harvest a 2‐acrylamido‐caprolactam (ACL) monomer. Subsequent reversible addition–fragmentation chain transfer copolymerization of the obtained monomer with oligo(ethylene glycol)acrylate (OEGA) gave well‐defined P(ACL‐co‐OEGA) with low distribution. Nuclear magnetic resonance , size exclusion chromatography, and matrix‐assisted laser desorption ionization–time‐of‐flight–mass spectrometry measurements indicated the controlled feature of the polymerization. Moreover, the resultant copolymers demonstrated thermoresponsiveness, and the cloud points (Tcp) can be adjusted from 34 to 79 °C, by changing pH values, and the fraction of cyclic lysine. These results suggested that these lysine‐based thermoresponsive polymers might be used as new materials in biomedical fields. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 862–868

The First Synthesis of Periodic and Alternating Glycopolymers by RAFT Polymerization: A Novel Synthetic Pathway for Glycosaminoglycan Mimics.

This study concerned the controlled synthesis of periodic glycopolymers by reversible addition-fragmentation chain transfer (RAFT) copolymerization. To this end, maltose- and lactose-substituted vinyl ethers (MalVE and LacVE, respectively) and maltose-substituted maleimide (MalMI) were newly synthesized. RAFT copolymerization of MalVE and ethyl maleimide (EtMI) (monomer feed ratio: MalVE:EtMI = 1:1) afforded periodic glycopolymers (poly(MalVE-co-EtMI)) consisting of major parts of alternating structure (-(MalVE-EtMI)n-) and a small part of consecutive sequences of EtMI (–EtMI-EtMI-). Occurrence of the latter sequences was caused by the homopolymerizability of maleimide under the present polymerization condition, and the formation of the consecutive sequences of EtMI was successfully suppressed by varying the monomer feed ratio. RAFT copolymerization of LacVE and EtMI was also found to proceed and similarly yielded periodic glycopolymers (poly(LacVE-co-EtMI)). Moreover, RAFT copolymerization of LacVE and MalMI (monomer feed ratio: LacVE:MalMI = 1:1) was performed to give copolymers (poly(LacVE-co-MalMI)) having composition ratio of LacVE/MalMI ≈ 36/64. The resultant periodic glycopolymers poly(MalVE-co-EtMI) and poly(LacVE-co-EtMI) were subjected to lectin binding assay using concanavalin A and peanut agglutinin, exhibiting the glycocluster effect. Moreover, these glycopolymers obtained from the copolymerization of VE and MI were found to be non-cytotoxic.

Starlike Branched Polyacrylamides by RAFT Polymerization-Part I: Synthesis and Characterization.

Starlike branched polyacrylamides (SB-PAMs) were synthesized using reversible addition–fragmentation chain transfer copolymerization of acrylamide (AM) and N,N′-methylenebis(acrylamide) (BisAM) in the presence of 3-(((benzylthio) carbonothioyl)thio)propanoic acid as a chain transfer agent, followed by chain extension with AM. The amount of incorporated BisAM in the core and the amount of AM during chain extension have been systematically varied. Core structures were achieved by incorporation of total monomer ratios [BisAM]/[AM] ranging from 0.010 to 0.143. The obtained macromolecular chain transfer agents had weight average molecular weights in the range of (2.2–7.8) × 103 Da and polydispersity indices between 1.2 and 15.1. Kinetic experiments were performed to investigate the extent of control of polymerization. Finally, the expansion of the core structures by chain-extension polymerization resulted in the successful preparation of high molecular weight SB-PAMs with apparent molecular weights ranging from 19 to 1250 kDa.

Hyper-Cross-Linked Polymer with Enhanced Porosity by In Situ Removal of Trimethylsilyl Group via Electrophilic Aromatic Substitution.

We report the synthesis of microporous hyper-cross-linked polymers (HCPs) with increased specific surface area and porosity by the in situ removal of trimethylsilyl (TMS) groups during hyper-cross-linking. We synthesized poly(4-trimethylsilylstyrene-co-vinylbenzyl chloride-co-divinylbenzene)s (P(TMSS-co-VBzCl-co-DVB)s) with different compositions by reversible addition-fragmentation chain transfer copolymerization and converted them into HCPs by reacting with FeCl3 in 1,2-dichloroethane. The nearly quantitative removal of the TMS groups was observed during the reaction following the electrophilic aromatic substitution mechanism, where the TMS group shows higher reactivity than an aromatic hydrogen. Substantial enhancement in pore characteristics including surface area, microporosity, and mesoporosity was noticed up to a certain level of TMSS incorporation, compared with HCP derived from P(VBzCl-co-DVB). We suggest the porogenic TMS group increases porosity mainly by in situ removal via facilitated substitution reaction, which creates permanent voids in the hyper-cross-linked network. The use of TMSS provides a feasible and complementary route to tuning the pore characteristics of HCPs by varying DVB content, and is applicable to the synthesis of hierarchically porous polymers containing micropores within a mesoporous framework from block polymer precursors.

Controlled Radical Copolymerization of Cinnamic Derivatives as Renewable Vinyl Monomers with Both Acrylic and Styrenic Substituents: Reactivity, Regioselectivity, Properties, and Functions.

A series of cinnamic monomers, which can be derived from naturally occurring phenylpropanoids, were radically copolymerized with vinyl monomers such as methyl acrylate (MA) and styrene (St). Although the monomer reactivity ratios were close to zero for all the cinnamic monomers, such as methyl cinnamate (CAMe), cinnamic acid (CA), N-isopropyl cinnamide (CNIPAm), cinnamaldehyde (CAld), and cinnamonitrile (CN), they were incorporated into the copolymers and significantly increased the glass transition temperatures despite the relatively low incorporation rates of up to 40 mol % due to their rigid 1,2-disubstituted structures. The regioselectivity of the radical copolymerization of CAMe was evaluated on the basis of the results of ruthenium-catalyzed atom transfer radical additions as model reactions. The obtained products suggest that the radicals of MA and St predominantly attack the vinyl carbon of the carbonyl side of CAMe and that the propagation of CAMe mainly occurs via the styrenic radical. The ruthenium-catalyzed living radical polymerization, nitroxide-mediated polymerization (NMP), and reversible addition-fragmentation chain transfer (RAFT) polymerization provided the copolymers with controlled molecular weights, narrow molecular weight distributions, and controlled comonomer compositions. The copolymers of N-isopropylacrylamide (NIPAM) and CNIPAm prepared via RAFT copolymerization showed thermoresponsivity with a lower critical solution temperature (LCST) that could be tuned by altering the comonomer incorporation and a higher LCST than the copolymers of NIPAM and St, which possessed similar molecular weights and similar NIPAM contents, due to the additional N-isopropylamide groups in the CNIPAm units compared to the St units.

Synthesis of stimuli-responsive chitosan nanocomposites via RAFT copolymerization for doxorubicin delivery

In this study, a unique stimuli-responsive hydrogel nanocomposite was prepared via surface reversible addition fragmentation chain transfer (RAFT) copolymerization of acrylic acid and N‑isopropyl acrylamide onto chitosan and subsequent in situ synthesis of magnetic Fe3O4 nanoparticles. In the next age, the structure and morphology of synthetic magnetic nanocomposite were characterized by FTIR, XRD, VSM, SEM, and TEM techniques. The modified hydrogel nanocomposite was employed as an excellent carrier for controlled releasing of anticancer drug doxorubicin (DOX). The results indicated that the maximum of DOX loading efficiency of nanocomposite was 89%. Notably, in vitro drug release studies showed that DOX was released in a sustained-release manner for the nanocomposites. From the results of in vitro release studies, dual temperature and pH responsiveness of the nanocomposite was demonstrated, and 82% of total DOX was released from the hydrogel within 2 days. Due to the unique structures and properties, the chitosan-based nanocomposite may be utilized as a promising drug carrier for controlled and sustained release of anticancer drugs.

Synthesis of magnetic functionalized MWCNT nanocomposite through surface RAFT co-polymerization of acrylic acid and N-isopropyl acrylamide for removal of cationic dyes from aqueous solutions

In this study, magnetic multi-walled carbon nanotube (MMWCNT) composites were prepared via surface reversible addition fragmentation chain transfer (RAFT) co-polymerization of acrylic acid (AA) and N-isopropyl acrylamide (NIPAM) in the presence of Fe3O4 nanoparticles. First, a novel RAFT agent (RA) was prepared and then immobilized onto the surface of MWCNT to fabricate RA-g-MWCNT. Then, Fe3O4 nanoparticles were attached onto the surface of RA-g-MWCNT. Finally, RAFT co-polymerization of AA and NIPAM monomers was carried out via Fe3O4-g-RA-g-MWCNT RAFT agent. The structure and morphology of the prepared polymer-coated MWCNT was examined by FTIR, SEM, TEM, XRD, VSM, and TGA. The adsorption behaviours of the cationic dyes were studied. The equilibrium isotherm and kinetics of cationic dyes were investigated. Thermodynamics investigations also depicted that the adsorptions of cationic dyes were spontaneous and endothermic in nature. The synthesized dye adsorbent with high adsorption capacities, reusability, and easy recovery makes it as a good candidate for wastewater treatment.

Estimation of Reactivity Ratios in the RAFT Copolymerization of Styrene and Glycidyl Methacrylate

AbstractThe bulk reversible addition‐fragmentation chain transfer (RAFT) copolymerization of glycidyl methacrylate (GMA) and styrene (S) at several GMA molar feed fractions in the presence of 2‐cyano isopropyl dodecyl trithiocarbonate as RAFT agent and 1,10‐azobis(cyclohexane carbonitrile) as initiator is reported. The reaction conditions are similar to those used in the industrial production of crystal and high‐impact polystyrene by free radical polymerization with the purpose of synthesizing well‐defined copolymers in current industrial processes with only minor changes. Reactivity ratios calculated with linear Kelen–Tüdos, extended Kelen–Tüdos, and nonlinear regression (error in all variables) methods are reported. The results obtained suggest that the RAFT process modifies copolymer composition development. Increased preference for the monomer with the higher reactivity ratio is observed.

Stepwise Light-Induced Dual Compaction of Single-Chain Nanoparticles.

A photochemical strategy for the sequential dual compaction of single polymer chains is introduced. Two photoreactive methacrylates, with side chains bearing either a phenacyl sulfide (PS) or an α-methylbenzaldehyde (photoenol, PE) moiety, are selectively incorporated by one-pot iterative reversible-addition fragmentation chain transfer copolymerization into the outer blocks of a well-defined poly(methyl methacrylate) based ABC triblock copolymer possessing a nonfunctional spacer block (Mn = 23 400 g mol-1 , Đ = 1.2; ≈15 units of each photoreactive moieties of each type) as well as in model statistical copolymers bearing only one type of photoreactive unit. Upon UVA irradiation, PS and PE lead to highly reactive thioaldehydes and o-quinodimethanes, which rapidly react with dithiol and diacrylate linkers, respectively. The monomerfunctional copolymers are employed to establish the conditions for controlled intramolecular photo-crosslinking, which are subsequently applied to the bifunctional triblock copolymer. All compaction/folding experiments are monitored by size-exclusion chromatography and dynamic light scattering. The dual compaction consists of two events of dissimilar amplitude: the first folding step reveals a large reduction in hydrodynamic diameters, while the second compaction lead to a far less pronounced reduction of the single-chain nanoparticles size, consistent with the reduced degrees of freedom available after the first covalent compaction step.

Syntheses of triblock bottlebrush polymers through sequential ROMPs: Expanding the functionalities of molecular brushes

Syntheses of triblock bottlebrush polymers through sequential ROMPs: Expanding the functionalities of molecular brushes

Metal‐containing ionic liquid‐based, uncharged–charged diblock copolymers that form ordered, phase‐separated microstructures and reversibly coordinate small protic molecules

Metal‐containing ionic liquid‐based, uncharged–charged diblock copolymers that form ordered, phase‐separated microstructures and reversibly coordinate small protic molecules

Synthesis and charcterization of diblock copolymers containaing monothio-orthoester functions using raft polymerization

The acyclic and cyclic monothio-orthoester monomers were synthesized by modification of aromatic monomers containing dithioester function in the side chain. Reversible addition-fragmentation chain transfer (RAFT) polymerization was employed for the preparation of polymers containing a dithioester end as macro-chain transfer agents (macro-CTA) using 4-benzyl methyldithiobenzoate (BMDTB) as chain transfer agent (CTA) and 2,2-azobisisobutyronitrile (AIBN) as initiator. A series of diblock copolymers were prepared by RAFT copolymerization of MVDTB, MMMS and MVPOCO, using the different macro-chain transfer agents (macro-CTA) and AIBN as initiator. All polymerizations were carried out at 60 °C for 24 or 30 hours in dry THF. Homopolymers and diblock copolymers are characterized by 1 H NMR, 13 C NMR, IR, SEC, DSC and TGA.