Synthesis of [?CH2C(CO2Et)2CH2Ar?]n polymers and their unique optical properties by through‐space interactions between Ar and CO groups

Polymers of type [? CH₂C(CO₂Et)₂CH₂Ar? ]_n (Ar = 1,4‐phenylene, 2,6‐naphthylene, 9,10‐anthrylene, or 1,4‐phenylene‐ethynylene‐1,4‐phenylene) were synthesized by alkylation of diethyl malonate with XCH₂ArCH₂X (X = Cl or Br). These polymers exhibited unexpectedly enhanced UV absorption and strong, broad, bathochromically shifted fluorescence spectra compared with the parent Ar compounds. The origin of these photophysical characteristics was postulated to be a configuration interaction between the π→π* excitation of the aromatic moiety and the n→π* excitation of the carbonyl moiety on the trimethylene tether via intramolecular charge transfer. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Jacket‐like structure of donor–acceptor chromophores‐based conducting polymers for photovoltaic cell applications

Through the Stille coupling polymerization, a series of soluble acceptor/donor quinoxaline/thiophene alternating conducting polymers with a hole‐transporting moiety of carbazole as a side chain ( PCPQT ) has been designed, synthesized, and investigated. The UV–vis measurement of the charge‐transferred type PCPQT s of different molecular weights with low polydispersity exhibits a red shifting of their absorption maximum from 530 to 630 nm with increasing chain length (M_n: from 1100 to 19,200). The HOMO and LUMO energy levels of PCPQT can be determined from the cyclic voltammetry measurement to be ?5.36 and ?3.59 eV, respectively. Solar cells made from PCPQT/PCBM bulk heterojunction show a high open‐circuit voltage, V_oc of ～0.75 V, which is significantly higher than that of a solar cell made from conventional poly(3‐hexyl thiophene)/ PCBM as the active polymer PCPQT has lower HOMO level. Further improvements are anticipated through a rational design of the new low band‐gap and the structurally two‐dimensional donor–acceptor conducting polymers. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1607–1616, 2010     

A new soluble conducting polymer and its electrochromic devices

A new polythiophene derivative was synthesized by both chemical and electrochemical oxidative polymerization of 1‐(1‐phenylethyl)‐2,5‐di(2‐thienyl)‐1H‐pyrrole (PETPy). Of which the chemical method produces a polymer that is completely soluble in organic solvents. The structures of both the monomer and the soluble polymer were elucidated by nuclear magnetic resonance (¹H and ¹³C NMR) and Fourier transform infrared (FTIR) spectroscopy. The average molecular weight has been determined by gel permeation chromatography to be M_n = 3.29 × 10³ for the chemically synthesized polymer. Polymer of PETPy was synthesized via potentiostatic electrochemical polymerization in acetonitrile (AN)/NaClO₄/LiClO₄ (0.1 M) solvent–electrolyte couple. Characterizations of the resulting polymer were performed by cyclic voltammetry, FTIR, scanning electron microscopy, and UV–vis spectroscopy. Four‐probe technique was used to measure the conductivities of the samples. Moreover, the spectroelectrochemical and electrochromic properties of the polymer films were investigated. In addition, dual‐type polymer electrochromic devices based on P(PETPy) with poly(3,4‐ethylenedioxythiophene) were constructed. Spectroelectrochemistry, electrochromic switching, and open circuit stability of the devices were studied. They were found to have good switching times, reasonable contrasts, and optical memories. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2215–2225, 2006     

Optically high transparency and light color of organosoluble polyamides containing trifluoromethyl and kink diphenylmethylene linkage

New polyamides were prepared directly from a diamine, bis[4‐(2‐trifluoromethyl 4‐aminophenoxy)phenyl] diphenylmethane, containing an electron‐withdrawing trifluoromethyl group and a kink diphenylmethylene linkage with various aromatic dicarboxylic acids having inherent viscosities ranging from 0.66 to 0.83 dL g^?1. All the polyamides showed outstanding solubility and could be easily dissolved in amide‐type polar aprotic solvents (e.g., N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide, and N,N‐dimethylformamide) and even dissolved in less polar solvents (e.g., pyridine, cyclohexanone, and tetrahydrofuran). The dielectric constants of the polyamide films were 3.37–3.87 (100 KHz) and decreased with an increase in the frequency, which ranged from 1 Hz to 100 KHz. A low coefficient of thermal expansion for the polyamides was observed in the range of 54–78 ppm/°C (by thermomechanical analysis). These polyamides showed excellent thermal stability, and the 10% weight loss temperatures were in the range of 484–507 °C in an atmosphere of nitrogen. The polymers had an initial modulus of 1.8–2.2 GPa. The polyamides with kink and electron‐withdrawing trifluoromethyl units afforded light‐color polymer films with high transmittance in the visible region (400–700 nm), and their cutoff wavelength was lower than 362 nm. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4559–4569, 2005     

Synthesis and unexpected electrochemical behavior of the triphenylamine‐based aramids with ortho‐ and para‐trimethyl‐protective substituents

Two series of new organosoluble polyamides with methyl‐substituted triphenylamine (MeTPA) units showing anodically electrochromic characteristic were prepared from the phosphorylation polyamidation reaction of two diamine monomers, 4,4′‐diamino‐2″,4″,6″‐trimethyltriphenylamine (Me₃TPA‐diamine; 2 ) and 4,4′‐diamino‐4″‐methyltriphenylamine (MeTPA‐diamine; 2 ′), with various dicarboxylic acids, respectively. These polymers were readily soluble in many polar solvents and showed useful levels of thermal stability associated with relatively high glass‐transition temperatures (T_g) (314–329 °C) and high char yields (higher than 62% at 800 °C in nitrogen). In addition, the polymer films showed reversible electrochemical oxidation, high coloration efficiency (CE), low switching time, and anodic green electrochromic behavior. The unexpected electrochemical behavior of higher oxidation potential and lower electrochemical stability of Me₃TPA‐polyamides I than MeTPA corresponding polymers could be attributed to the higher steric hindrance of ortho‐substituents in Me₃TPA moieties, thus made the resonance stabilization of cation radical much more difficult for the Me₃‐substituted phenyl ring. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

Ion-beam irradiation effects on polyimide-UV–vis and infrared spectroscopic study

Ion-beam irradiation effects on polyimide, Kapton™, were studied with respect to optical and electronic properties. Stack films of Kapton™ (12.5 μm thick) were irradiated to various ion beams in air or vacuo at room temperature and subjected to ultraviolet–visible (UV–vis) spectroscopy, and change in absorbance and energy gap is discussed. The UV–vis absorption spectrum, which is assigned to the transition of electrons in benzene rings from π to π* orbital, upon He²⁺ (6 MeV/u) irradiation in air, shifted towards longer wavelength direction for all cases, and the shift was more obvious for higher linear energy transfer (LET) ion beams. The energy gap of the transition was estimated, and the H⁺ and He²⁺ ion beams caused little change in the transition energy gap Eg, while the heavier ions such as C⁶⁺ and Si¹⁴⁺ caused more significant decrease. This decrease is assumed to the structural changes around benzene rings, and the infrared spectroscopy revealed breakage in imide groups next to benzene ring in the repeating unit of polyimide.     

Synthesis and characterization of soluble conjugated polymers having pyrene moiety in the main chain

Three new alternating conjugated polymers consisting of pyrene and 3‐dodecylthiophene ( PPyMT ), 4,4′‐didodecyl‐2,2′‐bithiophene ( PPyBT ), or 9,9‐didodecylfluorene ( PPyFlu ) moieties have been prepared using Suzuki coupling reaction or Sugimoto approaches. The polymers were readily soluble in common organic solvents and exhibited good thermal stability in nitrogen and air atmospheres. The structures and optical properties of the polymers were characterized by NMR, FTIR, XRD, UV–vis, and fluorescence spectroscopy. PPyMT and PPYBT showed blue‐light emission in solution, whereas PPyFlu performed blue‐light emitting in film state. The polymers exhibited an intermolecular aggregation and structural ordering due to pyrene–pyrene π–π stacking interaction. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

Anthracene‐ and thiophene‐containing MEH‐PPE‐PPVs: Synthesis and study of the effect of the aromatic ring position on the photophysical and electrochemical properties

This contribution reports on the synthesis and characterization of thiophene‐ ( P1 , P2 , and P3 ) and anthracene‐ ( P4 and P5) containing PPE‐PPV copolymers. The thermostable, soluble and film‐forming polymers were fully characterized by NMR, IR and ELEM . ANAL .; they exhibit high molar masses with polydispersity indices below 2.5. The position of the thiophene in the polymeric backbone has insignificant influence on the spectroscopic properties of the polymers. In contrast, the anthracene‐containing polymers reveal position dependent optical properties. A constant bathochromic shift of 50 nm was observed going from P4 , where anthracene is surrounded by two double bonds, to P5 , where anthracene is at the bridge between a triple bond and a double bond, as well as from P5 to P6 where anthracene is surrounded by two triple bonds. This correlates to the decrease of the observed anthracene band around 255 nm going from P4 through P5 to P6 , amounting to the degree of contribution of the anthracene unit to the main chain conjugation. The phenomenon known as CN‐PPV effect was observed in the case of P4 [Φ_f (solution) = 3%, Φ_f (solid) = 13%]. Electrochemical studies carried out under absolute inert conditions revealed lower electrochemical band gap energies, E , than E . © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2243–2261, 2009     

Studies of interaction between a new synthesized minor-groove targeting artificial nuclease and DNA

Nuclease plays an important role in molecular biology, such as DNA sequencing. Synthetic polyamide conjugates can be considered as new tool in the selective inhibition of gene expression and as potential drugs in anticancer or antiviral chemotherapy. In this paper, a new synthesized minor-groove targeting artificial nuclease, oligopyrrol-containing peptide, was reported. It was found that this new compound can bind DNA in AT-riched minor groove with high affinity and site specificity. DNA binding behavior was determined by UV-vis and circular dichroism (CD) methods. It was indicated that compound 6 can enhance the Tm of oligomer DNA from 51.8 to 63.5 degrees C and possesses large binding constant (Kb=8.83x10(4)L/mol).     

Synthesis and properties of polyimides derived from 1,4‐bis(4‐aminophenoxy)‐2‐(6‐oxido‐6H‐dibenz[c,e] [1,2]oxaphosphorin‐6‐yl) phenylene

A new phosphorus‐containing aromatic diamine, 1,4‐bis(4‐aminophenoxy)‐2‐(6‐oxido‐6H‐dibenz[c,e] [1,2]oxaphosphorin‐6‐yl) phenylene ( 3 ) was synthesized by the nucleophilic aromatic substitution of 2‐(6‐oxido‐6H‐dibenz[c,e] [1,2]oxaphosphorin‐6‐yl)‐1,4‐dihydroxy phenylene ( 1 ) with 4‐fluoronitrobenzene, followed by catalytic hydrogenation. Light color, flexible, and creasable polyimides with high molecular weight, high glass transition, high thermal stability, improved organosolubility, and good oxygen plasma resistance were synthesized from the condensation of ( 3 ) with various aromatic dianhydrides in N,N‐dimethylacetamide, followed by thermal imidization. The number‐average molecular weights of polyimides are in the range of 7.0–8.3 × 10⁴ g/mol, and the weight‐average molecular weights are in the range of 12.5–16.5 × 10⁴ g/mol. The T_gs of these polyimides range from 230 to 304 °C by differential scanning calorimetry and from 228 to 305 °C by DMA. These polyimides are tough and flexible, with tensile strength at around 100 MPa. The degradation temperatures (T_d 5%) and char yields at 800 °C in nitrogen range from 544 to 597 °C and 59–65 wt %, respectively. Polyimides 5c and 5e , derived from OPDA and 6FDA, respectively, with the cutoff wavelength of 347 and 342 μm, respectively, show very light color. These polyimides also exhibit good oxygen plasma resistance. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2897–2912, 2007     

Synthesis of poly(1‐chloro‐2‐arylacetylene)s with high cis‐content and examination of their absorption/emission properties

A series of 1‐chloro‐2‐arylacetylenes [Cl‐C?C‐Ar, Ar = C₆H₅ ( 1 ), C₆H₄‐p‐i Pr ( 2 ), C₆H₄‐p‐Oi Pr ( 3 ), C₆H₄‐p‐NHC(O)Ot Bu ( 4 ), and C₆H₄‐o‐i Pr ( 5 )] were polymerized using (tBu₃P)PdMeCl/silver trifluoromethanesulfonate (AgOTf) and MoCl₅/SnBu₄ catalysts. The corresponding polymers [poly( 1 )–poly( 5 )] with weight‐average molecular weights of 6,500–690,000 were obtained in 10–91% yields. THF‐insoluble parts, presumably high‐molecular weight polymers, were formed together with THF‐soluble polymers by the Pd‐catalyzed polymerization. The Pd catalyst polymerized nonpolar monomers 1 and 2 to give the polymers in yields lower than the Mo catalyst, while the Pd catalyst polymerized polar monomers 3 and 4 to give the corresponding polymers in higher yields. The ¹H NMR and UV–vis absorption spectra of the polymers indicated that the cis‐contents of the Pd‐based polymers were higher than those of the Mo‐based polymers, and the conjugation length of the Pd‐based polymers was shorter than that of the Mo‐based polymers. Pd‐based poly( 5 ) emitted fluorescence most strongly among poly( 1 )–poly( 5 ). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 382–388     

Synthesis of imidazole‐containing conjugated polymers bearing phenol unit as side group and excited state intramolecular proton transfer‐mediated fluorescence

Dibromobenzimidazole and dibromoimidazole bearing hydroxyl group‐protected phenol unit ( 1 and 2 ) were prepared and they showed an intramolecular hydrogen bonding between ether oxygen and amino proton of imidazole. The palladium‐catalyzed Suzuki coupling polymerization of 1 and 2 with benzene bis(boronic acid) derivatives gave soluble polymers ( 3 and 4 ), where the molecular weights were limited probably due to the coordination ability of imidazole to palladium metal. The phenol hydroxyl groups were subsequently deprotected using BBr₃ to obtain 3 ′ and 4 ′. From the ¹H NMR spectra, the complete conversion to the hydroxyl group and the formation of another type of intramolecular hydrogen bonding between hydroxyl proton and imine nitrogen were confirmed. In the UV and PL spectra of 3 ′ and 4 ′, the excited state intramolecular proton transfer (ESIPT) occurred to shift the emission spectra toward lower energy region compared to 3 and 4 . Especially, the PL spectrum of 3 ′ demonstrated large stokes shift (145 nm) in THF solution. The ESIPT‐mediated fluorescence was influenced by the addition of methanol and trifluoroacetic acid, which inhibited the formation of intramolecular hydrogen bonding. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4822–4829, 2009     

Synthesis and characterization of fluorene end‐labeled polystyrene with atom transfer radical polymerization

Fluorene end‐labeled polystyrene was prepared by atom transfer radical polymerization with 9‐bromofluorene as the initiator. Reactions were carried out in bulk or tetrahydrofuran solutions at temperatures of 80 °C or above. Analysis by gel permeation chromatography indicated that the polymers formed had low polydispersities with molecular weights consistently 2–5 times higher than calculated based on monomer‐to‐initiator ratios. Coupling of two fluorenyl radicals, formed by activation of the 9‐bromofluorene, was found to compete with initiation, leading to the higher‐than‐expected molecular weight values while giving rise to a fluorene dimer. UV–vis spectrometry indicated near‐quantitative fluorene labeling of the polystyrene. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2657–2665, 2005     

Functionalization of silver and gold nanoparticles using amino acid conjugated bile salts with tunable longitudinal plasmon resonance

The vital bioactivities of bile salts are physiologically important molecules. The concept of using bile acids and their conjugates in nanoscience is a novel idea, which opens up fascinating prospects and gives way for various versatile properties. Here in, we report novel strategy for the synthesis of aqueous stable, silver and gold nanoparticles (Ag & AuNPs) using naturally occurring amino acid conjugated sodium salt of taurocholate (NaTC) and glycocholate (NaGC) as reducing and capping agents. The formation of nanoparticles was kinetically monitored using UV–vis spectroscopy at different time intervals. It was noticed, that the rate of reduction of AgNO₃ is much faster than the HAuCl₄ at fixed concentration of bile salts. Furthermore, the size and shape of the NPs are controlled and achieved by changing the nature of bile salts. The synthesized nanoparticles were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques for morphological studies. The interaction between nanoparticles with bile salts was investigated using FT-IR spectroscopy, cyclic voltammetry (CV) and thermogravimetric analysis (TGA).     

Electrochemical impedance studies of the undoping process of platinum phthalocyanine charge transfer microcrystals

Platinum phthalocyanine (PtPc) microcrystal films undergo three successive electrochemical oxidations. Each of these processes is associated with anion insertion or doping. The reverse process of anion insertion, undoping, has been investigated using electrochemical impedance spectroscopy and in-situ UV–vis spectroscopy. The impedance theory of conductive polymer films developed by Vorotyntsev et al. is applicable to this process. The kinetics of the undoping process depend upon the previous oxidative treatment, and thus the doping level. Three different states of the film can be demarcated, depending on the degree of oxidation (and thus the degree of doping) of the PtPc film. These are called the lightly doped, the conductive and the over-doped state, respectively. For lightly doped films, the film conductivity, the redox capacitance, the diffusion coefficient for charge transport and the rate of electrochemical reaction all decrease with decreasing potential. The film conductivity depends upon the concentration of free charge carriers. For the more highly doped conductive film, all of the above parameters are greatly enhanced, and the electrochemical reaction is accelerated and proceeds at a very high rate. The potential dependence of the redox capacitance and the diffusion coefficient depends on the type of anion. During undoping at 0 V, unusually high diffusion coefficients with a magnitude of order 10⁻² cm² s⁻¹ are observed and are attributed to the strong interactions between the electronic and ionic carriers during the phase transformation. For the over-doped film, undoping leads to an increase in the film conductivity and electrochemical reaction rate. The potential dependence of the redox capacitance and diffusion coefficients for charge transport implies strong interactions within the film. Hypsochromic shifts in UV–vis spectra with decreasing potential indicate conformational relaxation during the undoping process. SEM investigation confirms that the doped film swells during the de-doping process.     

Synthesis and properties of through‐space conjugated polymers based on π–π stacked 1,3‐biarylpropane tethering units

Novel skipped‐π polymers in which the π‐components are connected with 2‐substituted trimethylene tethering units exhibit bathochromically shifted, broadened ultraviolet absorption with a unique lower‐energy absorption band and a largely red‐shifted fluorescent emission. These results suggest that through‐space π–π interactions owing to a stair‐like stacking substructure in these polymers extend the π‐conjugation of the components in the ground and excited states. As the photophysical properties of the polymers observed both in a solution and in a dried film are similar to those of the J‐aggregates of π‐molecules, these polymers may be considered as pseudo J‐stacking (or J‐like‐stacking) polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3412–3419     

Synthesis and characterization of soluble low‐bandgap oligothiophene‐[all]‐S,S‐dioxides‐based conjugated oligomers and polymers

The synthesis and characterization of a new family of soluble oligothiophene‐S,S‐dioxides and their use as building blocks to form polythiophene‐S,S‐dioxides via microwave‐assisted Stille coupling polymerization are described. Incorporation of the sulfone group into the polythiophene backbone leads to narrowing of the polymer bandgap, and while the energies of both Frontier orbitals in polythiophene‐S,S‐dioxide are lower with respect to polythiophenes, this tendency is considerably stronger for the lowest unoccupied molecular orbital than for the highest occupied molecular orbital, resulting in greater electron‐accepting ability. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Aggregation of polythiophene homopolymer and block copolymer in solution utilizing the characteristics of pyridine at the side chain

Poly[3‐(5′‐hexylpyridine‐2′‐yl)thiophene] ( P3PT ) (M_n = 13900, H‐T content = 90%) was prepared by the regioselective Grignard metathesis reaction and the subsequent Kumada coupling polymerization. Likewise, poly(3‐hexylthiophene)‐b‐poly[3‐(5′‐hexylpyridine‐2′‐yl)thiophene] ( P3HT‐b‐P3PT ) (M_n = 17,300) was synthesized in the one‐pot and successive monomer addition protocol, in which the segment ratio was calculated to be 56 ( P3HT )/44 ( P3PT ) base on the ¹H NMR spectrum. The absorption and emission spectra of homopolymer P3PT(H) , obtained by the protonation of the pyridine nitrogen, in THF/cyclohexane shifted to the longer wavelength as compared with those collected in THF, suggesting the aggregation in poor solvent. The aggregation of P3PT induced by the addition of Sc(OTf)₃ could be controlled by the molar ratio of pyridine and scandium complex. The protonated block copolymer P3HT‐b‐P3PT(H) was also subjected to the aggregate formation. The absorption maximum in THF/CH₃OH showed a bathochromic shift and the fluorescence emission was almost quenched. From the ¹H NMR spectra and DLS measurements, P3HT‐b‐P3PT(H) forms nanometer scale aggregates particularly with the insolubility and stacking of non‐ionic P3HT in alcohol as the driving force. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3383–3389     

Synthesis and characterization of polythiophene derivatives with nitrogen heterocycles on the side chain

The Grignard metathesis reaction of 2,5‐dibromo‐3‐(5′‐hexylpyridine‐2′‐yl)thiophene ( M1 ) with i‐PrMgCl afforded 5‐bromo‐2‐chloromagnesio‐3‐(5′‐hexylpyridine‐2′‐yl)thiophene ( GM1 ) in the 86% selectivity. The Kumada coupling polymerization by Ni(dppp)Cl₂ gave poly M1 having the roughly controlled molecular weight between 6700 and 23,400. The characterization using the gel permeation chromatographic and matrix‐assisted laser desorption/ionization‐time of flight mass spectra indicated the diffusion of the nickel catalyst from the propagating end. Based on the GC and ¹H NMR spectra, the head‐to‐tail content of poly M1 was calculated to be 89%. The regioselective Grignard metathesis reactions of 5,5′‐dibromo‐4‐(5″‐hexylpyridine‐2″‐yl)‐2,2′‐bithiophene ( M2 ) and 5,5′‐dibromo‐4‐(5″‐hexylpyrimidine‐2″‐yl)‐2,2′‐bithiophene ( M3 ) also occurred at the ortho‐position of the nitrogen heterocycle. The Kumada coupling polymerizations gave poly M2 and poly M3 having the head‐to‐tail content of 75% and 85%, respectively. The UV–vis spectra of polymers suggested that the polymer conformation becomes more planar in the order of poly M1 < poly M3 < poly M2 , which was investigated by the theoretical calculation of the model oligomers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2166–2174     

Atom transfer radical polymerization of hexyl acrylate and preparation of its “all‐acrylate” block copolymers

This investigation reports the polymerization of hexyl acrylate (HA) using atom transfer radical polymerization technique and subsequently the preparation of its di‐ and triblock copolymers with methyl methacrylate. Atom transfer radical polymerization of HA was investigated using different initiators and CuBr or CuCl as catalyst in combination with varying ligands, e.g., 2,2′‐bipyridine and N,N,N′,N″,N″‐pentamethyl diethylenetriamine. Reaction parameters were adjusted to successfully polymerize HA with well‐defined molecular weights and narrow polydispersity indices. The polymerization was better controlled by the addition of polar solvents, which created a homogeneous catalytic system. UV–vis analysis showed that the polar solvent, acetone coordinated with copper (I), changes the nature of the copper catalyst, thereby influencing the dynamic equilibrium of activation–deactivation cycle. This resulted in improved control over polymerization as well as in lowering the polydispersity indices, but at the cost of polymerization rate compared with the bulk process. The presence of ? Br end group in the polymer chains was confirmed by ¹H NMR as well as MALDI‐TOF mass analysis. In addition, poly(hexyl acrylate) was used as macroinitiator to prepare various “all‐acrylate” block (diblock, triblock) copolymers that were characterized by GPC and ¹H NMR. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3499–3511, 2008