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Induction, transfer, and modulation of intriguing supramolecular chirality were achieved in a chiral domino-type polymer system using a chiral α-end azobenzene (Azo) moiety as one chiral terminus and achiral Azo repeating units as building blocks. The Azo polymers prepared by atom transfer radical polymerization were imparted with well-controlled chain lengths and a chiral moiety at a well-defined position. One chiral terminus can effectively dictate the helical orientation of the achiral Azo stacks in the aggregation state. The spacer length between the chiral residue and the achiral repeating units dominates the preferred handedness of the side-chain Azo stacks. For instance, the R-configuration moiety with a short alkyl chain (with 0, 2, and 3 carbons) induces right-handed supramolecular chirality, whereas those with long alkyl chains (with 4, 5, and 6 carbons) induce the opposite helical orientation of the Azo units. Moreover, the chiral regulation of polymer aggregates is successfully achieved using the unique photoisomerization transition of the Azo chromophore and the heat-assisted reassembly approach. Chiral induction and chiral-to-achiral communication are further verified viatheoretical simulations.

Single-walled carbon nanotubes (SWCNTs) have attracted significant attention due to their outstanding properties. For their wide applications in electronics and optoelectronics, pure semiconducting SWCNTs (s-SWCNTs) and their precise placement are preconditions. Recent advances have focused on developing effective strategies to separate s-SWCNTs from raw SWCNTs, a mixture of metallic and semiconducting nanotubes, and deposit s-SWCNTs on target substrates. Herein, a polyfluorene-based alternative copolymer (PFBP) containing the benzophenone group was employed. PFBP achieved higher yield for s-SWCNTs than the well-studied poly(9,9-dioctylfluorene) through solution process. Subsequently, the dispersed s-SWCNTs were immobilized on a flexible polyethylene terephthalate in a facile manner by the photoreactive benzophenone group upon exposure to UV irradiation, and chemically robust patterns were fabricated from micro to macro scales through photomasks. Our method accomplished by utilizing photoimmobilization is a simple cleaning procedure and an important step forward in pitch scaling for further applications of conjugated polymer wrapped s-SWCNTs.

Sequence plays a crucial role in dictating the properties and applications of both natural and artificial polymers. Therefore, chemists have made great efforts to control the sequence of monomers along a polymer chain in the past decades. This focus review outlines the recent advances in sequence-controlled polymers (SCPs), mainly based upon the author’s research on constructing SCPs through maleimide chemistry, and discusses their potential applications.

The first example of atom tramsfer radical polymerization using activators generated by electron transfer (AGET ATRP) of styrene in bulk and solution was investigated in the presence of catalytic amounts of NaOH or Fe(OH)3, using FeCl3·6H2O as the catalyst, (1-bromoethyl)benzene (PEBr) as the initiator, vitamin C (VC) as the reducing agent, and a cheap and commercially available tetrabutylammonium bromide (TBABr) or tetra-n-butylphosphonium bromide (TBPBr) as the ligand. It was found that both the polymerization rate and controllability over molecular weights and molecular weight distributions (∼1.2) of the resultant polymers could be enhanced in the presence of the catalytic amounts of base as compared with those without base. For example, the polymerization rate of bulk AGET ATRP with a molar ratio of [St]0/[PEBr]0/[FeCl3·6H2O]0/[TBABr]0/[VC]0/[NaOH]0= 250/1/1/2/2/1.5 using NaOH as the additive was much faster than that without NaOH. The former was 3.5 times the latter. Furthermore, the polymerization of styrene could be successfully carried out even in the conditions when the amount of iron salts, FeCl3·6H2O as the catalyst, reduced to ppm level.

Nanoparticle morphology significantly affects the application of nanometer-scale materials. Understanding nanoparticle formation mechanisms and directing morphological control in nanoparticle self-assembly processes have received wide attention. Herein, a series of brush-like amphiphilic liquid crystalline block copolymers, PChEMAm-b-POEGMAn, containing cholesteryl mesogens with different hydrophobic/hydrophilic block ratios were designed and synthesized. The self-assembly behaviors of the resulting PChEMAm-b-POEGMAnblock copolymers in different solvents (tetrahydrofuran/H2O, 1,4-dioxane/H2O, and N,N-dimethylformamide) were investigated in detail. Desirable micellar aggregates with well-organized architectures, including short cylindrical micelles, nanofibers, fringed platelets, and ellipsoidal vesicles with smectic micellar cores, were observed in 1,4-dioxane/H2O with an increasing hydrophobic block ratio. Although both amphiphilicity and smectic order governed the self-assembly, these two factors were differently balanced in the different solvents. This unique supramolecular system provides a new strategy for the design of advanced functional nanomaterials with tunable morphologies.

Transition metal-mediated atom transfer radical polymerization (ATRP) is well known as one of successful reversible deactivation radical polymerizations for synthesizing various designable structures. However, the resultant polymers are usually contaminated or colored by large amounts of metal catalyst, which does not facilitate its industrialization. How to efficiently separate and recycle the metal catalyst has triggered lots of interest in green chemistry and ATRP. In this review, we mainly focus on a recyclable liquid/liquid thermo-regulated phase separable catalysis (TPSC) strategy applied in ATRP, which provides a facile and efficient method combining homogeneous reaction with heterogeneous separation just by simply changing temperature. TPSC-based ATRP systems include but not limit to the following systems: fluorous biphasic system, lower alcohol/alkane biphasic system, poly(ethylene glycol) (PEG) biphasic system and thermo-regulated ionic liquids biphasic system and so on.

Special research attention has been paid to phosphorus-containing materials and their corresponding applications. This mini review considers recent publications devoted to the “living”/controlled radical (co)polymerization of phosphorus-containing monomers. In addition, different properties of the polymers involved in the phosphonate group in various chemical environments are demonstrated, and their potential applications are briefly discussed.

By introducing flexible spacers between pendant fullerenes and the backbone, side-chain fullerene polyesters with high fullerene content and good solubility were synthesized by condensation polymerization. These polyesters are a new class of soluble high refractive index polymers (HRIPs) with the highest value of 1.79 at the sodium D line (589 nm).

A novel strategy of preparing multifunctional nanoparticles (NPs) with near infra red (NIR) fluorescence and magnetism showing good hydrophilicity and low toxicity was developed via surface-initiated atom transfer radical polymerization with activators generated by electron transfer (AGET ATRP) of poly(ethylene glycol) monomethyl ether methacrylate (PEGMA) and glycidyl methacrylate (GMA) employing biocompatible iron as the catalyst on the surface of silica coated iron oxide (Fe3O4@SiO2) NPs. The small molecules (CS2), a NIR fluorescent chromophore, can be fixed into the covalently grafted polymer shell of the NPs by chemical reaction through a covalent bond to obtain stable CS2 dotted NPs Fe3O4@SiO2@PPEGMA-co-PGMA@CS2. The fluorescence intensity of the as-prepared NPs could be conveniently regulated by altering the silica shell thickness (varying the feed of silica source TEOS), CS2 feed, or the feed ratio of VPEGMA/VGMA, which are easily realized in the preparation process. Thorough investigation of the properties of the final NPs including in vivodual modal imaging indicate that such NPs are one of the competitive candidates as imaging agents proving a promising potential in the biomedical area.

The RAFT agents RAFT‐1 and RAFT‐2 were used for RAFT polymerization to synthesize well‐defined bimodal molecular‐weight‐distribution (MWD) polymers. The system showed excellent controllability and “living” characteristics toward both the higher‐ and lower‐molecular‐weight fractions. It is important that bimodal higher‐molecular‐weight (HMW) polymers and block copolymers with both well‐controlled molecular weight (MW) and MWD could be prepared easily due to the “living” features of RAFT polymerization. The strategy realized a mixture of higher/lower‐molecular‐weight polymers at the molecular level but also preserved the features of living radical polymerization (LRP) of the RAFT polymerization.

We demonstrate surface‐initiated activators generated by electron transfer atom‐transfer radical polymerization (SI‐AGET ATRP) of methyl methacrylate (MMA) and tert‐butyl acrylate (t‐BA) on activated carbon (AC), and polyacrylic acid (PAA) graft AC (AC@PAA) is obtained after hydrolysis of poly(tert‐butyl acrylate) [P(t‐BA)]. Interestingly, the sorption capabilities of the copper ions by AC@PAA are larger than AC and can be adjusted by varying chain lengths of grafted PAA, giving these materials potential application in wastewater treatment. The linear polymerization kinetics, linear evolution of the molecular weight of the cleaved polymer and monomer conversion all demonstrate a well‐controlled polymerization.

The combination of zero‐valent iron (Fe(0) powder) and copper(II) bromide was used to mediate the polymerization of methyl methacrylate (MMA) or styrene (St) at 25 ° C. The results demonstrated that the solvent played an important role on the polymerization rate and molecular‐weight control. The polymerization in toluene displayed a poorly controlled process with remarkably low polymerization rate. With dimethyl sulfoxide (DMSO) as solvent, the polymerization proceeded in a relatively high rate, and the number‐average molecular weights were controlled especially at higher conversion. High conversions (80%) of St could be achieved with narrow molecular weight distributions in DMSO at 25 °C. It was supposed that Fe(0) played a dual role, the activator for the generation of active radical and the reducing agent for CuBr2.

Optically active cofacial π–π phthalocyanine (Pc) stacked supramolecules were spontaneously and successfully generated from a mixture of four possible geometric isomers (C4h, D2h, C2v, Cs) of achiral 4(5),4′(5′),4′′(5′′),4′′′(5′′′)‐tetracarboxymetallophthalocyanine (tcPcM; M=Ni, Cu) induced by an equimolar amount of inexpensive chiral diamine molecular sources in DMSO/CHCl3mixed solvent under optimized conditions of the volume ratio of poor/good cosolvents, the molar ratio of chiral molecular diamine to tcPcM, the cavity metal of phthalocyanine, and the addition order of the amines. The sign and amplitude of circular dichroism spectra due to the supramolecular chirality and structure of the diamine molecules are impossible to remove by additions of the antipode diamine and trifluoroacetic acid. The chiral diamine was partly contained in nanofibers, and that retained in the solution can be recycled and reused to induce optically active tcPcM supramolecules.

A novel method for iron‐mediated atom transfer radical polymerization with activators generated by electron transfer (AGET) ATRP of a polar monomer, methyl methacrylate (MMA), is developed in the presence of catalytic amounts of inorganic base NaHCO3or Na2CO3. The polymerization is carried out using FeCl3· 6H2O as the catalyst, triphenylphosphine as the ligand, ethyl 2‐bromoisobutyrate as the initiator, and vitamin C as the reducing agent at 70 °C. It is found that the addition of base into the polymerization system enhances the polymerization rate significantly but does not destroy the controllability over the molecular weight and molar‐mass dispersity.

Vitamin C sodium salt (VC‐Na) is used as a reducing agent for the iron‐mediated AGET ATRP (atom transfer radical polymerization using activators generated by electron transfer) of methyl methacrylate (MMA) with FeCl3/tris‐(3,6‐dioxa‐heptyl) amine (TDA‐1) as a catalyst complex and ethyl 2‐bromoisobutyrate (EBiB) as an initiator in the absence/presence of a limited amount of air. As compared with the reported iron‐mediated AGET ATRP of MMA, the current catalyst system shows a faster polymerization rate. For example, a conversion of 82.3% is obtained in 3.1 h with a molar ratio of [MMA]0/[EBiB]0/[FeCl3.6H2O]0/[TDA‐1]0/[VC‐Na]0= 500:1:1:3:0.5 at 90 °C. The kinetics of polymerizations of MMA in bulk or anisole demonstrate features of “living” or controlled free‐radical polymerization, such as the number‐average molecular weights increasing linearly with monomer conversion and maintaining narrow molecular weight distributions ($\overline {M} _{w} $/$\overline {M} _{n} $= 1.20–1.44).

Wagenburg‐Design: Definierte cyclische Poly(4‐vinylbenzylcarbazol)‐Polymere (PVBCZs) mit unterschiedlichen Molekulargewichten wurden effizient durch eine Folge aus radikalischer Atomtransfer‐Polymerisation (ATRP) und einer Klick‐Reaktion aufgebaut (siehe Bild; Σ=Azidgruppe, Δ=Alkinylgruppe). Die cyclischen PVBCZs haben höhere Glasübergangstemperaturen als ihre linearen Vorstufen und verfügen über eine stärkere Fluoreszenz.

Circle the wagons: Well‐defined cyclic poly(4‐vinylbenzylcarbazole) (cyclic PVBCZ) polymers with differing molecular weights were prepared efficiently by successive atom‐transfer radical polymerization (ATRP) and a click reaction (see picture; Σ=azide, Δ=alkynyl groups). The cyclic PVBCZ displayed a higher glass transition temperature than its linear precursor and has a higher fluorescence emission.

Polished 316 L stainless steel (SS) was first treated with air plasma to enhance surface hydrophilicity and was subsequently allowed to react with 2-(4-chlorosulfonylphenyl)ethyltrimethoxysilane to introduce an atom transfer radical polymerization (ATRP) initiator. Accordingly, the surface-initiated atom transfer radical polymerization of polyethylene glycol methacrylate (PEGMA) was carried out on the surface of the modified SS. The grafting progress was monitored by water contact angle measurements, X-ray photoelectron spectroscopy and atomic force microscopy. The polymer thickness as a function different polymerization times was characterized using a step profiler. The anticoagulative properties of the PEGMA modified SS surface were investigated. The results showed enhanced anticoagulative to acid-citrate-dextrose (ACD) blood after grafting PEGMA on the SS surface.

A new method, AGET ATRP mediated by an iron(III) catalyst using Fe(0) powder as a reducing agent and MMA as a model monomer, is reported. The polymerizations can be carried out in the absence or presence of a limited amount of air and show the features of a “living”/controlled radical polymerization. MMA conversions of 90.3 and 80.0% can be obtained in 3.5 and 4.0 h in the absence/presence of a limited amount of air, respectively, for the iron‐mediated AGET ATRP with a molar ratio of [MMA]0/[EBiB]0/[FeCl3· 6H2O]0/[PPh3]0/[Fe(0)]0= 600:1:0.5:2:0.1 at 90 °C. PMMA with molecular weights of 55 060 and 47 790 g · mol−1and with molar‐mass dispersity of 1.24 and 1.28, respectively, can be obtained correspondingly.

Photoelectrochemical (PEC) cells based on silicon nanowire arrays (SiNWs) have, to date, exhibited modest power conversion efficiency (PCE) and suffered serious degradation, though they exhibit advantageous properties of charge-transfer/transport properties at the radial-junction and strong light-trap capabilities. The main challenge for this low-cost PEC cell is the surface photooxidation and photocorrosion of the silicon surface when contacting with the electrolyte. In this report, SiNWs derivatized with covalently attached methyl groups, prepared viaa two-step chlorination/methylation procedure, demonstrate excellent stability even in the presence of water. Furthermore, SiNWs PEC cells utilizing a room temperature ion liquid (IL) acting as an electrolyte solvent display neglectable surface oxidation. A PEC cell based on a platinum (Pt) nanodots decorated and methylated (−CH3) SiNWs electrode in combination with an IL electrolyte yields a PCE of 6.0% and shows excellent stability under simulated air mass (AM) 1.5 solar spectrum irradiation, while the PCE of a PEC cell based on planar silicon only exhibits 0.003%. The inherent performance of these structures indicates that a −CH3(Pt) SiNWs electrode in combination with an IL is a new approach to develop a high-performance and low-cost solar cell.

A novel main‐chain azobenzene cyclic polymer, cyclic‐PEHPA, has been successfully synthesized by ‘click’ cyclization of the α‐alkyne‐ω‐azido hetero‐difunctional linear precursors (linear‐PEHPA), which is synthesized by a step‐growth polymerization of the 3′‐ethynylphenyl[4‐hexyl‐(2‐azido‐2‐methyl‐ propionate) phenyl] azobenzene (EHPA). Gel permeation chromatography, and 1H NMR and FT‐IR spectra confirmed the complete transformation of linear‐PEHPA into cyclic‐PEHPA. With the same molecular weights, the cyclic‐PEHPAs are found to have higher glass transition temperatures than the linear‐PEHPAs, but almost the same decomposition temperatures. In addition, the obtained cyclic azobenzene polymer with lower molar mass shows a slightly better trans–cis–transphotoisomerization ability than the corresponding linear‐PEHPA.

Abstract: This tutorial review summarizes recent progress in the research field of controlled/“living” radical polymerization (CLRP) from Soochow University. The present paper gives a broad overview of the mechanism study and molecular design in CLRP. The mechanism study in CLRP aided by microwave, initiated by γ-radiation at low temperature, mediated by iron, in reversible addition-fragmentation chain transfer (RAFT) polymerization and the mechanism transfer between different CLRP processes are reviewed and summarized. The molecular design in CLRP, especially in RAFT polymerization for mechanism study, and in achieving tailor-made functional polymers is studied and discussed in the later part.

A clickable alkyne monomer, PgMA, was successfully polymerized in a well‐controlled manner viasingle electron transfer initiation and propagation through the radical addition fragmentation chain transfer (SET‐RAFT) method. The living nature of the polymerization was confirmed by the first‐order kinetic plots, the linear relationships between molecular weights and the monomer conversions while keeping relatively narrow $\overline M _{\rm w} /\overline M _{\rm n}$(≤1.55), and the successful chain‐extension with MMA. The better controllability of SET‐RAFT than other CRP methods is attributed to the less competitive termination in view of the presence of the CTA as well as the Cu(II) that is generated in situ. Moreover, a one‐pot/one‐step technique combining SET‐RAFT and “click chemistry” methods has been successfully employed to prepare the side‐chain functionalized polymers.

Initiators for continuous activator regeneration in atom transfer radical polymerization (ICAR ATRP) is a new technique for conducting ATRP. ICAR ATRP has many strong advantages over normal ATRP, such as forming the reductive transition metal species in situ using oxidatively stable transition metal species and a lower amount of metal catalyst in comparison with the normal ATRP system. In this work, the iron‐mediated ICAR ATRP of styrene and methyl methacrylate are reported for the first time using oxidatively stable FeCl3· 6H2O as the catalyst in the absence of any thermal radical initiator. The kinetics of the polymerizations and effect of different polymerization conditions are studied. It is found that the polymerization of styrene can be conducted well even if the amount of iron(III) is as low as 50 ppm.

Two new copperI complexes, Cubdmpm2PF61 bis3,5dimethyl1Hpyrazol1ylmethane bdmpm and CuµbdmppMeCN2PF622 2,6bis3,5dimethyl1Hpyrazol1ylpyridine bdmpp, were prepared by reactions of CuMeCN4PF6 with bdmpm or bdmpp in MeCN. Xray analysis revealed that 1is a mononuclear complex with the central Cu being chelated by two bdmpm ligands. 2has a doublestranded helicate structure in which each of the two CuµbdmppMeCNcations is linked by the other bdmpp ligand. Both 1and 2exhibited high catalytic activity in the polymerization of methyl methacrylate MMA. Even though the ratio of MMA to catalyst was raised up to 1 000:1, the PDI for 1reaction time was fixed at 5 h is below 1.6 and the conversion is up to 66.0 while that for 2reaction time was fixed at 6 h is below 1.5 and the conversion is up to 75.2. In addition, the effects of solvents, reaction temperatures as well as ratios of MMA to catalyst were also investigated.

The atom transfer radical polymerization of styrene using activators generated by electron transfer (AGET ATRP) has been carried out in bulk in a limited amount of air at 110 °C, using 1,3,5‐(2′‐bromo‐2′‐methylpropionato)benzene (BMPB) as an initiator and FeCl3· 6H2O/tris(3,6‐dioxaheptyl) amine (TDA‐1)/ascorbic acid (VC) as a novel FeIII‐mediated catalyst system. The results of the polymerizations demonstrate the features of ‘living’/controlled free‐radical polymerization, such as the number‐average molecular weights being close to their corresponding theoretical values and increasing linearly with monomer conversion, and narrow molecular weight distributions ($\overline M _{\rm w} /\overline M _{\rm n}$= 1.18–1.26). The end functionality of the obtained polymers was confirmed by 1H and 13C NMR spectra as well as a chain‐extension reaction.

A novel procedure, atomtransfer radical polymerization using activators generated by electron transfer AGET ATRP mediated by iron catalyst, was developed, using an oxidatively stable FeCl3triphenylphosphine as a catalyst complex, ascorbic acid as a reducing agent, and methyl methacrylate as a monomer. The polymerization can be conducted successfully in the presence of a limited amount of air and shows the features of “living”controlled freeradical polymerizations such as numberaverage molecular weights increasing linearly with monomer conversion and narrow molecular weight distributions. The living feature of the obtained polymer was further verified by a chain extension experiment.

Summary:A novel amphiphilic ABCBA‐type pentablock copolymer with properties that are sensitive to temperature and pH, poly(2‐dimethylaminoethyl methacrylate)‐block‐poly(2,2,2‐trifluoroethyl methacrylate)‐block‐poly(ε‐caprolactone)‐block‐poly(2,2,2‐ trifluoroethyl methacrylate)‐block‐poly(2‐dimethylaminoethyl methacrylate) (PDMAEMA‐ b‐PTFEMA‐b‐PCL‐b‐PTFEMA‐b‐PDMAEMA), was synthesized via consecutive atom transfer radical polymerizations (ATRPs). The copolymers obtained were characterized by gel permeation chromatography (GPC) and 1H nuclear magnetic resonance (NMR) spectroscopy, respectively. The aggregation behaviors of the pentablock copolymers in aqueous solution with different pH (pH = 4.0, 7.0 and 8.5) were studied. Transmission electron microscopic images revealed that spherical micelles from self‐assembly of the pentablock copolymer were prevalent in all cases. The mean diameters of these micelles increased from 34, 46, to 119 nm when the pH of the aqueous solution decreased from 8.5, 7.0, to 4.0, respectively.

Summary:The reversible addition–fragmentation chain transfer (RAFT) random copolymerization of N‐vinylcarbazole (NVC) and vinyl acetate (VAc) was carried out using s‐benzyl‐o‐ethyl dithiocarbonate (BED) as the chain transfer agent and 2,2′‐azoisobutyronitrile (AIBN) as the initiator in 1,4‐dioxane solution at 70 °C. The polymerization showed the characteristics of ‘living’ free radical polymerization behaviors: first order kinetics, linear relationships between molecular weight and conversion, and narrow polydispersity of the polymers. The reactivity ratios of NVC and VAc were calculated via the Kelen–Tudos (KT) and non‐linear error in variable (EVM) methods and showed as r1= 1.938 ± 0.191, r2= 0.116 ± 0.106. The thermal behavior of the copolymers with different content of NVC and VAc was investigated by DSC and TGA. The results showed that the introduction of a VAc segment into copolymer significantly reduced the Tgof the NVC homopolymers. FT‐IR spectra, fluorescence spectra, and cyclic voltammetric behavior of these copolymers were also measured and compared with those of NVC homopolymers. The copolymers showed similar oxidative behavior to the NVC homopolymer. However, there was only one reductive potential peak shown for the copolymers at about 0.058 V.

Summary:Two multifunctional iniferters, 1,4‐bis‐(α‐N,N‐diethyldithiocarbamyl‐isobutyryloxy)‐benzene (BDCIB) and 1,3,5‐tris‐(α‐N,N‐diethyldithiocarbamyl‐isobutyryloxy)‐benzene (TDCIB), were successfully synthesized and used as initiators to initiate the polymerization of styrene in the presence of a CuBr/PMDETA complex. The polymerization results demonstrated that the kinetic plots in all cases were first‐order to the monomer, the molecular weight of the polymers increased linearly with the monomer conversion; meanwhile, the molecular weight distribution of the polymer was kept to a very low value (Mw/Mn≤ 1.35). Furthermore, the measured molecular weights were very close to the calculated values, which indicated the high efficiency of the initiator for the polymerization of styrene. The effect of catalyst concentration and initiator concentration was not obvious and the influence of polymerization temperature was apparent, and the polymerization rate increased with the polymerization temperature. The results of chain‐extension and 1H NMR analysis proved that the polymer obtained was capped with diethylthiocarbamoylthiy (DC) group.

PBHEMA was prepared by RAFT polymerization in the presence of CPDN and AIBN. Diazobenzene groups were introduced into the sidechains by post-azo‐functionalization. The resulting polymers containing benzotriazol and azobenzene groups exhibited higher molecular weight than original polymers, narrow MWD ($\overline M _{\rm w} /\overline M _{\rm n} $ = 1.17–1.26) and adjustable degrees of functionality. Thermal stabilities and glass transition temperatures of the polymers increased with the introduction of diazo chromophores. The molecular weight of the polymer had a slight effect on the Tg of the polymer. The polymer showed partial crystallization as the diazo content increased above 36%.

Reversible addition–fragmentation chain transfer (RAFT) polymerizations of styrene under microwave irradiation (MI), with or without azobisisobutyronitrile, were successfully carried out in bulk at 72 and 98 °C, respectively. The results showed that the polymerizations had living/controlled features, and there was a significant enhancement of the polymerization rates under MI in comparison with conventional heating (CH) under the same conditions. The polymer structures were characterized with 1H and 13C NMR. The results showed the same structure for both polymers obtained by MI and CH. Successful chain‐extension experimentation further demonstrated the livingness of the RAFT polymerization carried out under MI. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6810‐6816, 2006

2‐(1‐Bromoethyl)‐anthraquinone (BEAQ) was successfully used as an initiator in the atom transfer radical polymerization of styrene with CuBr/N,N,N′,N′,N″‐pentamethyldiethylenetriamine as the catalyst at 110°C. The polymerizations were well controlled with a linear increase in the molecular weights (Mn's) of the polymers with monomer conversion and relatively low polydispersities (1.1 < weight‐average molecular weight (Mw)/Mn < 1.5) throughout the poly merizations. The resultant polystyrene thus possessed one chromophore moiety (2‐ethyl‐anthraquinone) at the α end and one bromine atom at the ω end, both from the initiator BEAQ. The intensity of UV absorptions of the resultant polymers decreased with increasing molecular weights of the polymers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2081–2085, 2006

A novel benzodithioate compound with an anthracene structure (anthracen-9-ylmethyl benzodithioate, AMB) was synthesized. Using AMB as the chain transfer agent, the RAFT polymerizations of styrene with AIBN as an initiator were carried out in difference reaction conditions. The polymerization results showed that AMB was an effective RAFT agent for the RAFT polymerizations of styrene with the characteristics of “living”/controlled free radical polymerization. The structure of the obtained polymers was characterized by 1H NMR. The results showed that the polymers contained an anthrancene moiety of AMB in the end and showed enhanced fluorescence property than AMB in DMF solution. The chain extension experiments of the obtained polymer with two different monomers (styrene and methyl acrylate) were successfully carried out. A novel benzodithioate compound with an anthracene structure (anthracen-9-ylmethyl benzodithioate, AMB) was synthesized. Using AMB as the chain transfer agent, the RAFT polymerizations of styrene with AIBN as an initiator were carried out in difference reaction conditions. The polymerization results showed that AMB was an effective RAFT agent for the RAFT polymerizations of styrene with the characteristics of “living”/controlled free radical polymerization. The structure of the obtained polymers was characterized by 1H NMR. The results showed that the polymers contained an anthrancene moiety of AMB in the end and showed enhanced fluorescence property than AMB in DMF solution. The chain extension experiments of the obtained polymer with two different monomers (styrene and methyl acrylate) were successfully carried out.

A series of (di)picolinic acids and their derivates are investigated as novel complexing tridentate or bidentate ligands in the iron‐mediated reverse atom transfer radical polymerization of methyl methacrylate in N,N‐dimethylformamide at 100 °C with 2,2′‐azobisisobutyrontrile as an initiator. The polymerization rates and polydispersity indices (1.32–1.8) of the resulting polymers are dependent on the structures of the ligands employed. Different iron complexes may be involved in iron‐mediated reverse atom transfer radical polymerization, depending on the type of acid used. 1H NMR spectroscopy has been used to study the structure of the resulting polymers. Chain‐extension reactions have been performed to further confirm the living nature of this catalytic system. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2912–2921, 2006

A novel reversible addition–fragmentation chain transfer polymerization (RAFT) of methyl methacrylate (MMA) in the presence of oxygen was carried out for the first time without added chemical initiators. The polymerization was mediated by 2‐cyanoprop‐2‐yl 1‐dithionaphthalate (CPDN) or cumyl dithionaphthalenoate (CDN) as RAFT agent. The polymerization demonstrated the features of a living/controlled radical polymerization. The polymerization rate increased with oxygen concentration. Polymers with molecular weight Mn up to 520,000 g/mol, polydispersity Mw/Mn ∼1.46 and RAFT efficiency Mn,th/Mn,GPC ∼1.026 in the case of CPDN and Mn ∼331,500 g/mol, Mw/Mn ∼1.35, and Mn,th/Mn,GPC ∼1.137 in the case of CDN were obtained. The possible mechanism of the thermal‐initiated RAFT polymerization of MMA in the presence of oxygen was discussed. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3343–3354, 2006

A new dinitroxide (1,4‐di (1‐oxy‐2,2,6,6‐tetramethyl‐1‐piperidin‐4‐yl)‐xylene) (DTPX) was synthesized and successfully used in stable free radical polymerization of styrene. The results of the polymerizations showed that the DTPX was a suitable mediating agent for stable free radical polymerization of styrene. However, it was found that the dinitroxide mediating process resulted in a higher level of decomposition of the internal bisalkoxyamine linkage in the polymer chain, which resulted in polymers possessing a terminal alkoxyamine and an adjacent hydroxylamine, and the decomposition became more obvious at high conversion through monitoring the change of molecular weights with the conversion by gel permeation chromatography and the polymer structure by 1H‐NMR. The reaction temperature showed obvious effects on the polymerization, and the polymerization of styrene at 110°C led to a better controlled polymerization than that at 125°C with narrower molecular weight distributions and slight decomposition of the nitroxide up to monomer conversions of 76.7%, however, the rate of the polymerization was decreased and an induction period appeared at 110°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1137–1145,2006

Two novel dithiocarbamates [2‐Y‐benzoimidazole‐1‐carbodithioic acid benzyl esters: Y = methyl (1b) or phenyl (1c)] were synthesized and successfully used in the reversible addition–fragmentation chain transfer (RAFT) polymerization of styrene in bulk with thermal initiation. The effects of the temperatures and concentration ratios of the styrene and RAFT agents on the polymerization were investigated. The results showed that the polymerization of styrene could be well controlled in the presence of 1b or 1c. The linear relationships between ln([M]0/[M]) and the polymerization time (where [M]0 is the initial monomer concentration and [M] is the monomer concentration) indicated that the polymerizations were first‐order reactions with respect to the monomer concentration. The molecular weights increased linearly with the monomer conversion and were close to the theoretical values. The molecular weight distributions [weight‐average molecular weight/number‐average molecular weight (Mw/Mn)] were very narrow from 5.3% conversion up to 94% conversion (Mw/Mn < 1.3). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 560–564, 2006

The plasma-initiated emulsion polymerization of MMA in the presence of 2-cyanoprop-2-yl 1-dithionaphthalate (CPDN) was first investigated. The polymers were characterized by GPC, 1H NMR, DSC and SEM. The results exhibit controlled polymerization characters: well-controlled molecular weight, relatively narrow polydispersity, molecular weight linearly increasing with conversion and successful chain extension reactions. The influence of the amount of the sodium dodecyl sulfate (SDS), CPDN concentration, plasma duration time on the polymerization rate, and micro-shape of the particle was investigated in this work. The plasma-initiation emulsion polymerization of octyl acrylate (OA) in the presence of CPDN is also carried out.

Reversible addition–fragmentation chain transfer (RAFT) polymerization of styrene was carried out in the presence of a novel RAFT reagent, bearing 1,3‐benzodioxole group, benzo [1,3]dioxole‐5‐carbodithioic acid benzo [1,3]dioxol‐5‐ylmethyl ester (BDCB), to prepare end‐functionalized polystyrene. The polymerization results showed that RAFT polymerization of styrene could be well controlled. Number–average molecular weight (Mn(GPC)) increased linearly with monomer conversion, and molecular weight distributions were narrow (Mw/Mn < 1.4). The successful reaction of chain extension and analysis of 1H NMR spectra confirmed the existence of the functional 1,3‐benzodioxole group at the chain‐end of polystyrene. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3535–3539, 2006

Optically active homopolymers and copolymers, bearing chiral units at the side chain and end chain, were prepared via atom transfer radical polymerization (ATRP) techniques. The well‐defined optically active polymers were obtained via the ATRP of pregnenolone methacrylate (PR‐MA), β‐cholestanol acrylate (CH‐A), and 20‐(hydroxymethyl)‐pregna‐1,4‐dien‐3‐one acrylate (HPD‐A) with ethyl 2‐bromopropionate as the initiator and CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine as the catalytic system. The experimental results showed that the polymerizations of PR‐MA, CH‐A, and HPD‐A proceeded in a living fashion, providing pendent chiral group polymers with low molecular weight distributions and predetermined molecular weights that increased linearly with the monomer conversion. Furthermore, the copolymers poly(pregnenolone methacrylate)‐b‐poly[(dimethylamino)ethyl methacrylate] and poly(pregnenolone methacrylate‐co‐methyl methacrylate) were synthesized and characterized with 1H NMR, transmission electron microscopy, and polarimetric analysis. In addition, when optically active initiators estrone 2‐bromopropionate and 20‐(hydroxymethyl)‐pregna‐1,4‐dien‐3‐one 2‐bromopropionate were used for ATRPs of methyl methacrylate and styrene, terminal optically active poly(methyl methacrylate) and polystyrene were obtained. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1502–1513, 2006

2,2,6,6‐Tetramethyl‐4‐[d‐(+)‐10‐camphorsulfonyl]‐1‐piperidinyloxy was synthesized and used as a chiral nitroxide for the bulk polymerizations of styrene initiated with benzoyl peroxide (BPO), tetraethylthiuram disulfide (TETD), and thermal initiation. The results showed that the polymerizations proceeded in a controlled/living way; that is, the kinetics presented approximately first‐order plots, and the number‐average molecular weights of the polymers with narrow molecular weight distributions (weight‐average molecular weight/number‐average molecular weight) increased with the monomer conversion linearly. The molecular weight distributions in the case of thermal initiation were narrower than those in the case of BPO and TETD, whereas the polymerization rate with BPO or TETD as an initiator was obviously faster than that with thermal initiation. In addition, successful chain‐extension reactions were carried out, and the structures of the obtained polymers were characterized by gel permeation chromatography and 1H NMR. The specific rotations of the polymers were also measured by polarimetric analysis. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1522–1528, 2006

The atom transfer radical polymerizations of styrene were successfully carried out in bulk and solution, respectively, at 115 °C, with a novel photoiniferter reagent, (1‐naphthyl)methyl N,N‐diethyldithiocarbamate (NMDC), as an initiator in the presence of copper (I) bromide and N,N,N′,N″,N″‐pentamethyldiethylenetriamine. The results showed that NMDC was an effective initiator with high initiation efficiency for ATRP of St. The polymerization rate was first‐order with respect to the monomer concentration and the molecular weights of the obtained polystyrene (PS) increased linearly with the monomer conversion, with very narrow molecular weight distributions (Mw/Mn = 1.07–1.29). The functionalized naphthalene‐labeled PS bearing N,N‐(diethylamino)dithiocarbamoyl group which was confirmed by 1H NMR analysis, and chain extension of the PS exhibited fluorescence and ultraviolet absorption in chloroform (CHCl3). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 510–518, 2006

The atom transfer radical polymerizations (ATRPs) of styrene initiated by a novel initiator, ethyl 2‐N,N‐(diethylamino)dithiocarbamoyl‐butyrate (EDDCB), in both bulk and solution were successfully carried out in the presence of copper(I) bromide (CuBr) and N,N,N′,N″,N″‐pentamethyldiethylenetriamine at 115 °C. The polymerization rate was first‐order with respect to the monomer concentration, and the molecular weights of the obtained polymers increased linearly with the monomer conversions with very narrow molecular weight distributions (as low as 1.17) up to higher conversions in both bulk and solution. The polymerization rate was influenced by various solvents in different degrees in the order of cyclohexanone > dimethylformamide > toluene. The molecular weight distributions of the produced polymers in cyclohexanone were higher than those in dimethylformamide and toluene. The results of 1H NMR analysis and chain extension confirmed that well‐defined polystyrene bearing a photo‐labile N,N‐(diethylamino)dithiocarbamoyl group was obtained via ATRP of styrene with EDDCB as an initiator. The polymerization mechanism for this novel initiation system is a common ATRP process. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 32–41, 2006

Polymerizations of styrene with azobisisobutyronitrile initiation or thermal initiation have been performed in the presence of dithiocarbamates with different N‐groups, that is, benzyl 4,5‐diphenyl‐1H‐imidazole‐1‐carbodithioate (2a), benzyl 1H‐1,2,4‐triazole‐1‐carbodithioate (2b), benzyl indole‐1‐carbodithioate (2c), benzyl 2‐phenyl‐indole‐1‐carbodithioate (2d), benzyl phenothiazine‐10‐carbodithioate (2e), benzyl 9H‐carbazole‐9‐carbodithioate (2f), and benzyl dibenzo[b,f]azepine‐5‐carbodithioate (2g). The results show that the structure of the N‐group of dithiocarbamates has significant effects on the activity of dithiocarbamates for the polymerization of styrene. 2a, 2b, 2c, 2d, and 2f are effective reversible addition–fragmentation chain transfer (RAFT) agents for the RAFT polymerization of styrene, and the polymerizations have good living characteristics. However, in the cases of 2e and 2g, the obtained polymers have uncontrolled molecular weights and broad molecular weight distributions. The polymerization rate is markedly influenced by the conjugation structure of the N‐group of the dithiocarbamate, and the polymerization rate of 2b is greater than that of 2a. For 2b, the rate of polymerization seems independent of the RAFT agent concentration. However, a significant retardation in the rate of polymerization can be observed in the case of 2c. 2d is more effective than 2c, and the substitution group of phenyl on this dithiocarbamate has obvious effects on the effectiveness of the controlled polymerization of styrene. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4849–4856, 2005

2‐Bromopropionic acid 2‐(4‐phenylazophenyl)ethyl ester, 2‐bromopropionic acid 6‐(4‐phenylazophenoxy)hexyl ester (BPA6), 2‐bromopropionic acid‐(4‐phenylazoanilide), and 2‐bromopropionic acid 4‐[4‐(2‐bromopropionyloxy)phenylazo]phenyl ester (BPPE) were used as initiators with monofunctional or difunctional azobenzene for the heterogeneous atom transfer radical polymerization of methyl methacrylate with a copper(I) chloride/N,N,N′,N″,N″‐pentamethyldiethylenetriamine catalytic system. The rates of polymerizations exhibited first‐order kinetics with respect to the monomer, and a linear increase in the number‐average molecular weight with increasing monomer conversion was observed for these initiation systems. The polydispersity indices of the polymer were relatively low (1.15–1.44) up to high conversions in all cases. The fastest rate of polymerization and the highest initiation efficiency were achieved with BPA6, and this could be explained by the longer distance between the halogen and azobenzene groups and the better solubility of the BPA6 initiator. The redshifting of the UV absorptions of the polymers only occurred for the BPPE‐initiated system. The intensity of the UV absorptions of the polymers were weaker than those of the corresponding initiators in chloroform and decreased with the increasing molecular weights of the polymers in all cases. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2358–2367, 2005

The reversible addition–fragmentation chain transfer (RAFT) polymerizations of 2‐naphthyl acrylate (2NA) initiated by 2,2′‐azobisisobutyronitrile were investigated with 2‐cyanoprop‐2‐yl 1‐dithionaphthalate (CPDN) as a RAFT agent at various temperatures in a benzene solution. The results of the polymerizations showed that 2NA could be polymerized in a controlled way by RAFT polymerization with CPDN as a RAFT agent; the polymerization rate was first‐order with respect to the monomer concentration, and the molecular weight increased linearly with the monomer conversion. The polydispersities of the polymer were relatively low up to high conversions in all cases. The chain‐extension reactions of poly(2‐naphthyl acrylate) (P2NA) with methyl methacrylate and styrene successfully yielded poly(2‐naphthyl acrylate)‐b‐poly(methyl methacrylate) and poly(2‐naphthyl acrylate)‐b‐polystyrene block polymers, respectively, with narrow polydispersities. The P2NA obtained by RAFT polymerization had a strong ultraviolet absorption at 270 nm, and the molecular weights had no apparent effect on the ultraviolet absorption intensities; however, the fluorescence intensity of P2NA increased as the molecular weight increased and was higher than that of 2NA. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2632–2642, 2005

The graft polymerization of methyl methacrylate and butyl acrylate onto poly(vinyl chloride‐co‐vinyl acetate) with atom transfer radical polymerization (ATRP) was successfully carried out with copper(I) thiocyanate/N,N,N′,N′,N″‐pentamethyldiethylenetriamine and copper(I) chloride/2,2′‐bipyridine as catalysts in the solvent N,N‐dimethylformamide. For methyl methacrylate, a kinetic plot of ln([M]0/[M]) (where [M]0 is the initial monomer concentration and [M] is the monomer concentration) versus time for the graft polymerization was almost linear, and the molecular weight of the graft copolymer increased with increasing conversion, this being typical for ATRP. The formation of the graft polymer was confirmed with gel permeation chromatography, 1H‐NMR, and Fourier transform infrared spectroscopy. The glass‐transition temperature of the copolymer increased with the concentration of methyl methacrylate. The graft copolymer was hydrolyzed, and its swelling capacity was measured. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 183–189, 2005

The bulk polymerization of styrene was investigated with tetramethylthiuram disulfide (TMTD) as an initiator in the presence of 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO) at 123 °C. The polymerization proceeded in a controlled/living way; that is, the polymerization rate was first‐order with respect to the monomer concentration, and the molecular weight increased linearly with conversion. The molecular weights of the polymers obtained were close to the theoretical values, and the molecular weight distributions were relatively low (weight‐average molecular weight/number‐average molecular weight = 1.1–1.3). The rate of polymerization with TMTD as an initiator was faster than that with benzoyl peroxide, and the rate was independent of the initial concentration of TMTD in the presence of TEMPO. The obtained polystyrene was functionalized with ultraviolet‐light‐sensitive &bond;SC(S)N(CH3)2 groups, which was characterized with 1H NMR spectroscopy. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 543–551, 2005