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Stimuli-responsive opposite emission (A)/absorption (B) polymer material (A∪B = Ω and A∩B = Ø) represents a novel polymer material that is difficult to prepare. Here, we demonstrate a one-pot strategy for the molecular design of stimuli-responsive opposite emission/absorption polymer material with intriguing properties of opposite emission/absorption and aggregation-induced emission (AIE) type nontraditional intrinsic luminescence (NTIL) in the visible region, through reversible addition-fragmentation chain transfer polymerization-induced emission (PIE) of the

The Barbier reaction is generally regarded as a one-pot Grignard reaction. Here, the Grignard reaction of cinnamaldehyde is demonstrated to give a 1,2-addition product, while the Barbier reaction of cinnamaldehyde yields a macromolecule with interesting aggregation-induced emission type non-conjugated luminescence properties, which indicates that the Barbier reaction cannot be regarded as a one-pot Grignard reaction.

A one-pot strategy for the design of stimuli-responsive luminescent polymers has been demonstrated through Barbier PIE, where the N,N-dimethyl moiety endows the polymers with both stimuli-responsive and red-shifted nonconjugated emission properties.

A novel method for the challenging synthesis of unsymmetrically tetrasubstituted NH-pyrroles from chalcone derivatives is reported. The pyrrolo[1,2-a]pyrimidine derivatives that were synthesized from NH-pyrroles exhibit AIE and AIEE property.

Barbier polymerization is realized at room-temperature with single-atom polymerization and polymerization-induced emission characteristics, which exhibits capability on sensitive explosive detection and artificial light-harvesting system fabrication.

The Barbier reaction, a classical name reaction for carbon-carbon bond formation, has played important roles in organic chemistry for over 120 years. The introduction of the Barbier reaction into polymer chemistry for the development of a novel Barbier polymerization, expands the methodology, monomer, chemical structure and property libraries of polymerization, aggregation-induced emission (AIE) and non-traditional intrinsic luminescence (NTIL). This mini review focuses on Barbier polymerization, including the brief introduction of the history and importance of polymerization methods design and the achievements of Barbier polymerization from molecular design strategies, functionalities and properties. An outlook of Barbier polymerization is also proposed. This mini review on Barbier polymerization therefore may cause inspirations to scientists in different fields.

The developments of the living alkene polymerization method have achieved great progress and enabled the precise synthesis of important polyalkenes with controlled molecular weight, molecular weight distribution, and architecture through an anionic, cationic or radical strategy. However, it is still challenging to develop a living alkene polymerization method through an all-in-one strategy where anionic and radical characteristics are merged into one polymerization species. Here, a versatile living polymerization method is reported by introducing a well-established all-in-one covalent-anionic-radical Barbier strategy into a living polymerization. Through this living covalent-anionic-radical Barbier polymerization (Barbier CARP), narrow distributed polystyrenes, with

The isosteric replacement of C═C by B-N units in conjugated organic systems has recently attracted tremendous interest due to its desirable optical, electronic and sensory properties. Compared with BN-, NBN- and BNB-doped polycyclic aromatic hydrocarbons, NBN-embedded polymers are poised to expand the diversity and functionality of olefin polymers, but this new class of materials remain underexplored. Herein, a series of polymers with BNB-doped π-system as a pendant group were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization from NBN-containing vinyl monomers, which was prepared via intermolecular dehydration reaction between boronic acid and diamine moieties in one pot. Poly{2-(4-Vinylphenyl)-2,3-dihydro-1H-naphtho[1,8-de][1,3,2]diazaborinine} (P1), poly{N-(4-(1H-naphtho[1,8-de][1,3,2]diazaborinin-2(3H)-yl)phenyl)acrylamide} (P2) and poly{N-(4-(1H-benzo[d][1,3,2]diazaborol-2(3H)-yl)phenyl)acrylamide} (P3) were successfully synthesized. Their structure, photophysical properties and application in metal ion detection were investigated. Three polymers exhibit obvious solvatochromic fluorescence. As fluorescent sensors for the detection of Fe

Luminescent polymer materials have gained considerable research efforts in the past decades and are generally molecular designed by extending the π system of the polymer main chain or by incorporating chromophores into the polymer chain, which suffer from poor solubility, difficult synthesis, or multi-step procedures. Meanwhile, according to the step-growth polymerization theory, synthesis of hyperbranched polymers from an AB-type monomer is still challenging. Herein, we report a one-pot synthesis of nonconjugated luminescent hyperbranched polymer material via Barbier hyperbranching polymerization-induced emission (PIE) from an AB-type monomer. The key step in the realization of the hyperbranched polymer is bi-functionalization of a mono-functional group. Through a Barbier reaction between an organohalide and an ester group in one pot, bi-functionalization of mono-functional ester is realized through two-step nucleophilic additions, resulting in hyperbranched polytriphenylmethanols (HPTPM). Attributed to through-space conjugation and inter- and intramolecular charge-transfer effects induced by polymer chain, nonconjugated HPTPMs are PIEgens, which are tunable by monomer structure and polymerization time. When all phenyl groups are rotatable, HPTPM is aggregation-induced emission type PIEgen. Whereas, it is aggregation-caused quenching type PIEgen if some phenyl groups are rotation forbidden. Further potential applications of PIEgen are in the fields of explosive detection and artificial light harvesting systems. This work, therefore, expands the monomer library and molecular design library of hyperbranched polymers through "bi-functionalization of mono-functional group" strategy, which eventually expands the preparation library of nonconjugated luminescent polymer materials through one-pot PIE from nonemissive monomer.

Pyrroles are among the most important heterocycles in pharmaceuticals and agrochemicals. Construction of pyrrole scaffolds with different substituents and a free NH group, however, is challenging. Herein, a metal-free method for the synthesis of unsymmetrically tetrasubstituted NH-pyrroles using a consecutive chemoselective double cyanation is reported. The desired pyrroles were obtained with yields up to 99% and good functional group tolerance. Mechanistic studies identified a reaction mechanism that features a subtle sequence of first cyano-addition and migration, followed by cyano-addition and aromatization to afford the pyrrole skeleton. Pyrrolo[1,2

α-Deuterated alcohols have important applications in pharmaceuticals and mechanism studies. Here, we report a new and practical strategy for the reductive deuteration of ketones using a Mg/BrCH2CH2Br/D2O system, which affords α-deuterated alcohols in good yields and with almost quantitative incorporation of deuterium. The synthetic value of this method has been demonstrated by the easy access to deuterated drugs or drug derivatives. This method may inspire the discovery of other deuterium-containing drugs.

Current synthetic strategies involving π-system coupling reactions for the molecular design of luminescent materials suffer from the challenging precise synthesis on the desired reactive site and also difficulty in solubility derived from the rigid structures of π-systems. Herein, a novel and versatile triarylmethanolation strategy for the molecular design of luminescent materials with facile synthesis and good solubility is reported. The prepared luminescent materials exhibit unique amorphization-induced emission (AmIE) behaviours, which represent an entropy-favoured and ubiquitous type of aggregation-induced emission that is currently famous and is contrary to crystallization-induced emission. Due to the outstanding AmIE behaviours, the luminescent materials exhibit applications in the fields of rewritable display and storage, extremely sensitive explosive detection at the ppb level, and high-efficiency artificial light-harvesting system with an antenna effect up to 21.3. This work therefore expands the methodology, structure, and functionality libraries of luminescent materials with outstanding properties in the application fields of explosive detection, energy transfer, and artificial light-harvesting systems.

As predicted by Flory–Stockmayer theory, precise control of polymer architecture, molecular weight, and molecular weight distribution in the polymerization of tri-vinyl monomers has been recognized as a considerable challenge in polymer chemistry. Multi-responsive polymers are generally designed by incorporating multiple sensitive moieties together in one polymer chain. However, this strategy suffers from issues of complicated synthesis and the compatibilities of these functional moieties. The design of multi-responsive polymers by incorporating only one sensitive moiety is of considerable importance. Here, we report the successful, well-controlled polymerization of tri-vinyl containing dynamic covalent boroxine (DCB) monomer, and utilization of DCB as a side-chain building block in the molecular design of a multi-responsive polymer. Benefiting from dynamic characteristics, the DCB-incorporated polymer exhibits tunable penta-responsive behavior leading to response/sensing of water, fluoride ion, and acid and base, as well as lower critical solution temperature-type thermo-responsive properties, which cover a wide temperature range, and with both solution–colloid transition and sol–gel transition observed. The utilization of only one DCB moiety in the design of the tunable penta-responsive polymer breaks the stimulus record of multi-responsive polymers, and opens up a new avenue in the molecular design and application of functional polymer materials.

A new type of organic proton donor for the strong-acid/base-free hydrogen evolution reaction is reported, by taking advantage of the electron deficiency of the boron center of borinic acid and the strong affinity and hydrolysis reaction between borinic acid and water with hydrogen ion formation. The borinic acid proton donor exhibits even higher current density than H2SO4 to promote hydrogen evolution performance in DMF.

A simple and efficient synthesis of NBN-doped conjugated polycyclic aromatic hydrocarbons (such as diazaborinines) has been accomplished by a catalyst-free intermolecular dehydration reaction at room temperature between boronic acid and diamine moieties with yields up to 99 %. Polycyclic aromatic hydrocarbons with a six-membered NBN ring are a new class of aggregation-induced emissive luminogens. Extremely sensitive detection of ppb levels of TNT by phenyl naphthodiazaborinine is straightforward. Visual detection of TNT is illustrated by fabrication of TNT test strips, which can detect as little as 100 ng of TNT powder. This simple and sensitive detection of TNT has potential applications in the area of public safety and security against terrorist activities.

The introduction of main group elements into conjugated scaffolds is emerging as a key route to novel optoelectronic materials. Herein, an efficient and versatile way to synthesize polymerizable 9,10-azaboraphenanthrene (BNP)-containing monomers by aromaticity-driven ring expansion reactions between highly antiaromatic borafluorene and azides is reported, and the corresponding conjugated small molecules and polymers are developed as well. The BNP-containing small molecules and conjugated polymers showed good air/moisture stability and notable fluorescence properties. Addition of fluoride ions to the BNP-based small molecules and polymers induced a rapid change in the emission color from blue to green/yellow, respectively, accompanied by strong intensity changes. The conjugated polymers showed better ratiometric sensing performance than small molecules due to the exciton migration along the conjugated chains. Further experiments showed that the sensing process is fully reversible. The films prepared by solution-deposition of BNP-based compounds in the presence of polycaprolactone also showed good ratiometric sensing for fluoride ions.

Electron-deficient borinic acid monomers and corresponding polymers were synthesized with different substituents via a one-pot reaction of Grignard reagents with trimethoxyborane and reversible addition–fragmentation chain transfer polymerization, respectively. Further investigations of substituent effects of borinic acid polymers (PBAs) were carried out, indicating that the thermoresponsive properties of PBAs benefit from the increase of steric hindrance of PBA substituent, while the binding affinity of PBAs with Alizarin Red S, 8-hydroxyquinoline (HQ), and fluoride ion decreases with the increase of steric hindrance of substituent. Attributed to the strong dative N → B bond and the strongly luminescent boron quinolate, the application of phenyl PBA for fluorescence detection of HQ is realized with high sensitivity at the ppm level. These results therefore confirm that borinic acid-containing polymer is a new type of stimuli-responsive polymer in the field of thermoresponsiveness over a wide temperature ...

α-Deuterated alcohols have important applications in pharmaceuticals and mechanism studies. Here, we report a new and practical strategy for the reductive deuteration of ketones using a Mg/BrCH

Luminescent polymers are generally constructed through polymerization of luminescent moieties. Polymerization itself, however, is mainly used for constructing polymer main chain, and the importance of polymerization on luminescence has yet to be explored. Here, we demonstrate a polymerization-induced emission strategy producing luminescent polymers by introducing Barbier reaction to hyperbranching polymerization, which allows luminescent properties to be easily tuned from the traditional type to an aggregation-induced emission type by simply adjusting the monomer structure and the polymerization time. When rotation about the phenyl groups in hyperbranched polytriphenylmethanols (HPTPMs) is hindered, HPTPMs exhibit traditional emission property. When all phenyl groups of HPTPM are rotatable, i.e., p,p',p″-HPTPM, it exhibits interesting aggregation-induced emission property with tunable emission colors from blue to yellow, by just adjusting polymerization time. Further applications of aggregation-induced emission type luminescent polymers are illustrated by the facile fabrication of white light-emitting diode (LED) and light-harvesting film with an antenna effect >14. This Barbier hyperbranching polymerization-induced emission provides a new strategy for the design of luminescent polymers and expands the methodology and functionality library of both hyperbranching polymerization and luminescent polymers.

Self-assembly of block copolymers (BCPs) in solution is a powerful technology to achieve a broad range of structures, such as spheres, cylinders, vesicles, and other hierarchical structures. However, the BCP self-assembly library is limited, especially with respect to tubular structures. Here we show a versatile strategy to expand the morphology library of block copolymer solution self-assemblies with tubular structures (including tubular dumbbells and tubules) via self-assembly of the most common diblock copolymers P4VP-b-PS BCPs in methanol. No special chemistry is needed in this strategy, which proves the universality of this method. The novelty of the strategy is to keep the BCPs both highly asymmetric and with very high molecular weight. The underlying formation mechanism and kinetics of these tubular structures were elucidated. The prepared tubular structures expand the structure library of BCP solution self-assemblies and open up a new avenue for the further applications of a variety of tubular mat...

Summary Polymerization and modification play central roles in polymer chemistry and are generally implemented in two steps, which suffer from the time-consuming two-step strategy and present considerable challenge for complete modification. By introducing the radical cascade reaction (RCR) into polymer chemistry, a one-step strategy is demonstrated to achieve synchronized polymerization and complete modification in situ. Attributed to the cascade feature of iron-catalyzed three-component alkene carboazidation RCR exhibiting carbon-carbon bond formation and carbon-azide bond formation with extremely high efficiency and selectivity in one step, radical cascade polymerization therefore enables the in situ synchronized polymerization through continuous carbon-carbon bond formation and complete modification through carbon-azide bond formation simultaneously. This results in a series of α, β, and γ poly(amino acid) precursors. This result not only expands the methodology library of polymerization, but also the possibility for polymer science to achieve functional polymers with tailored chemical functionality from in situ polymerization., Graphical Abstract, Highlights • Synchronized polymerization and modification • Radical cascade polymerization • Alkene functionalization polymerization, Polymer Chemistry; Organic Reaction; Polymers

The thermo-responsive properties of borinic acid polymers were investigated by experimental and molecular dynamics simulation studies. The homopolymer poly(styrylphenyl(tri-iso-propylphenyl)borinic acid) (PBA) exhibits an upper critical solution temperature (UCST) in polar organic solvents that is tunable over a wide temperature range by addition of small amounts of H2O. The UCST of a 1 mg mL(-1) PBA solution in DMSO can be adjusted from 20 to 100 °C by varying the H2O content from ∼0-2.5%, in DMF from 0 to 100 °C (∼3-17% H2O content), and in THF from 0 to 60 °C (∼4-19% H2O). The UCST increases almost linearly from the freezing point of the solvent with higher freezing point to the boiling point of the solvent with the lower boiling point. The mechanistic aspects of this process were investigated by molecular dynamics simulations. The latter indicate rapid and strong hydrogen-bond formation between BOH moieties and H2O molecules, which serve as crosslinkers to form an insoluble network. Our results suggest that borinic acid-containing polymers are promising as new "smart" materials, which display thermo-responsive properties that are tunable over a wide temperature range.

Borinic acid block copolymers have been prepared by reversible addition–fragmentation chain transfer (RAFT) polymerization and investigated as “smart materials” in sensory applications. Taking advantage of the hydrogen bond donating ability of the borinic acid groups, supramolecular aggregates of PNIPAM-b-PBA were generated by complexation with P4VP. The P4VP complex showed greatly improved fluoride ion detection efficiency relative to the PBA polymer by itself. The block copolymer PS-b-PBA was processed into porous films with tunable pore size by drop-casting from THF in the presence of trace amounts of water. A microporous polymer film that was deposited on an electrode was utilized as a biosensor for acetylthiocholine chloride detection after immobilization of acetylcholine esterase.

The Barbier reaction, a widely utilized reaction for carbon–carbon bond formation, has played important roles in modern organic chemistry for more than a century. Here, we show its successful introduction to polymer chemistry. Through one-pot Barbier polyaddition (both A2+B2 type and AB type) of monomers containing an organic halide and a benzoyl group, a series of phenylmethanol group containing polymers, including polymonophenylmethanol (PMPM), polydiphenylmethanol (PDPM), and polytriphenylmethanol (PTPM), have been synthesized. Para-PTPM exhibits interesting aggregation-induced emission, tunable thermo-responsive over a wide temperature range, sensory, luminescence enhancement of fluorescent dye in solid-state and processing properties. This significantly expands the libraries of monomer and polymer, and opens up an avenue for the design and application of functional polymer materials., The Barbier reaction, a widely utilized reaction for carbon–carbon bond formation, has played important roles in modern organic chemistry. Here, the authors show a one-pot Barbier polyaddition reaction of monomers containing an organic halide and a benzoyl group to form a series of phenylmethanol group containing polymers.

The morphology library of block copolymer (BCP) self-assemblies is limited, especially as far as tubular structures are concerned. Here, the morphology of clews of tubules is discovered for the first time by self-assembly of P4VP-b-PS BCPs with both high asymmetry and very high molecular weight, which successfully expands the morphology library of BCP self-assemblies.

A new type of smart borinic acid polymer with luminescence and multiple stimuli-responsive properties is reported. In DMSO with small amounts of water, the homopolymer PBA shows a tunable upper critical solution temperature (UCST). As the amount of water increases from 0 to 2.5 % (v/v), the UCST rises linearly from 20 °C to 100 °C (boiling point of water). Thus, the thermal responsive behavior can be tuned over a wide temperature range. Furthermore, polymer solutions in DMSO show a reversible response to fluoride ions, which can be correlated to the presence of the Lewis acidic borinic acid groups. Upon addition of fluoride, the polymer becomes soluble because the functional R2BOH groups are converted into ionic [R2BF2](-) groups, but turns insoluble again upon addition of H2O, which reverses this process.

A series of micelle-forming, amphiphilic copolymers or “polysoaps” with potential as dispersants for oil spill remediation has been synthesized via statistical RAFT copolymerization of specific molar ratios of 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and n-dodecyl acrylamide (DDAM). Control over composition, degree of polymerization, polydispersity, and reaction kinetics was attained by conducting the copolymerizations at 60 °C in dimethylformamide with AIBN and CEP as initiator and chain-transfer agent, respectively. Molecular weight, hydrodynamic dimensions, composition- and concentration-dependent associative properties, and hydrophobic domain characteristics in water for copolymers with 10, 20, 30, 40, 50, and 60 mol% feed of DDAM have been studied utilizing NMR, SEC/MALLS, DLS, SLS, surface tensiometry, and fluorescence spectroscopy. It was found that the lower hydrophobic content (10%, 20%, and 30%) polysoaps form multimeric associations as indicated by increasing hydrodynamic dimensions as concentration is increased. On the other hand, the higher hydrophobic content (40%, 50%, and 60%) polysoaps form unimolecular micelles with consistent sizes and with distinct hydrophobic cores over the entire concentration range probed. UV/Vis absorbance experiments provided additional insight into the association and sequestration properties of the polysoaps. The higher hydrophobic content polysoaps show increased capabilities for dissolution of pyrene as compared to SDS above its CMC. Finally, the cytotoxicity of these polysoaps was determined utilizing KB cell lines. The polysoaps of this study exhibited up to 60× less cytotoxicity than SDS as measured by IC50 values. It was also found that as the molecular weight of the polysoap increased, the cytotoxicity decreased. The results of this study point to potential of unimolecular micelles for oil spill remediation, allowing sequestration and subsequent hydrocarbon break-down by endogenous bacteria in the marine environment.

Free radical polymerization of B-vinyl- and B-styryl-functionalized azaborinine monomers gives well-defined hybrid polymers that were fully characterized by multinuclear NMR and GPC analysis; their solubility, thermal characteristics, and photophysical properties are dramatically different from those of the all-carbon polystyrene analogues.

A simplified one-pot and less harmful method has been introduced for the synthesis of borinic acid monomer. The corresponding borinic acid polymer (PBA) has been prepared by reversible addition-fragmentation chain transfer polymerization. Property investigations confirm the characteristics of PBA as a new type of "smart material" in the field of thermo-responsive polymer. The potential application of PBA in the field of enzymatic biofuel cell has been illustrated with a wide open circuit potential of 0.92 V.

A one-pot method is introduced for the successful synthesis of narrow-distributed (Đ = 1.22) vinyl polymer with both ultrahigh molecular weight (UHMW) (M w = 1.31 × 106 g mol-1 ) and micro-/nanomorphology under mild conditions. The method involves the following four stages: homogeneous polymerization, polymerization-induced self-assembly (PISA), PISA and reorganization, and PISA and multiple reorganizations. The key points to the production of UHMW polystyrene are to minimize radical termination by segregating radicals in different nanoreactors and to ensure sufficient chain propagation by promoting further reorganizations of these reactors in situ. This method therefore endows polymeric materials with the outstanding properties of both UHMW and tunable micro-/nanoparticles under mild conditions in one pot.

The assembly behavior of diblock copolymers in solution can be modulated by block length, block ratio, solvent properties, and preparation route. Different assembly morphologies such as spherical micelles, cylindrical micelles, vesicles, and large compound vesicles have been obtained for diblock copolymers with shorter solvated block, such as poly(acrylic acid)-b-polystyrene (PAA-b-PSt). In the present work, we reported an easy-going route to prepare PAA-b-PSt assemblies with different morphologies through reversible addition−fragmentation-transfer (RAFT) dispersion polymerization of styrene in methanol with trithiocarbonated PAA as macromolecular chain transfer agent. Because this RAFT dispersion polymerization exhibited controlled features, the consecutive growth of PSt block led to the successive transition of the obtained PAA-b-PSt assemblies from spherical micelles, cylindrical micelles, vesicles, to large compound vesicles, confirmed by the combination of electron microscopy, laser light scattering,...

A facile and feasible strategy for the preparation of vesicular morphologies has been developed using reversible addition-fragmentation chain transfer (RAFT) polymerization. The polymerization of styrene has been performed in a selected solvent, methanol, using S-1-dodecyl-S-(α,α'-dimethyl-α″-acetic acid)trithiocarbonate (TC)-terminated poly(4-vinylpyridine) as chain transfer agent and stabilizer. Various morphologies including spherical vesicles, nanotubes, and compound vesicles with different shapes are obtained by changing the feed ratios and reaction conditions. The final nanostructural materials are formed through formation of the block copolymers, self-assembly, and re-organization of the morphology in a one-pot polymerization. The latter two are induced by the propagation of PS blocks. The preparation of nanostructural materials can be performed at a concentration higher than 0.5 g · mL(-1) , thus this method offers a practical approach to prepare nanostructural materials on a large scale.

The atom transfer radical dispersion polymerization of 4-vinylpyridine (4VP) in an ethanol/H2O mixture displayed two stages of polymerization; the first stage is the formation of a diblock copolymer with the polymerization rate of 1.21 mol·L-1·h-1 before 1 h of polymerization, and the second is the main polymerization in micelles formed from the aggregation of the resultant block copolymers with the polymerization rate of 0.009 mol·L-1·h-1. The 2-bromoisobutyryl-terminated poly(ethylene glycol) methyl ether used in the polymerization acts as both a stabilizer and an initiator. The stable micelles with functional core were synthesized by a one-pot strategy via atom transfer radical dispersion copolymerization (ATRDCP) of 4VP and N,N‘-methylenebisacrylamide (MBA) in an ethanol/H2O solution for the first time. In the initial stage of polymerization, 4VP and MBA were copolymerized to form a block copolymer, PEG-b-(4VP-co-MBA), with pendent unreacted vinyl groups, and after phase separation at a critical chain...

Block copolymer (BCP) self-assembly is a versatile technique in the preparation of polymeric aggregates with varieties of morphologies. However, its morphology library is limited. Here, the discovery of pincushion of tubules is reported for the first time, via BCP self-assembly of poly(4-vinylpyridine)-b-polystyrene (P4VP-b-PS) with very high molecular weight (500 kDa) and asymmetry (2 mol% P4VP). The investigation confirms the importance of core-forming block length on morphology control of BCP self-assemblies, especially with respect to tubular structures. The morphology landscape of tubular structures is successfully established, where dumbbell of tubule, tubule, loose clew of tubules, tight clew of tubules, and pincushion of tubules can be prepared by adjusting the core-forming block length. This work therefore expands the structure library of BCP self-assemblies and opens up a new avenue for the further applications of these tubular materials.

A facile synthetic pathway for preparing block copolymers with pH-responsive L-glutamic acid segments for membrane disruption is reported. Aqueous reversible addition-fragmentation chain transfer (aRAFT) polymerization was first used to prepare biocompatible, nonimmunogenic poly[N-(2-hydroxypropyl)methacrylamide]. This macro chain transfer agent (CTA) was then converted into a macroinitiator via simultaneous aminolysis and thiol-ene Michael addition using the primary amine substituted N-(3-aminopropyl)methacrylamide. This macroinitiator was subsequently utilized in the ring-opening polymerization of the N-carboxyanhydride monomer of γ-benzyl-L-glutamate. After deprotection, the pH-dependent coil-to-helix transformations of the resulting HPMA-b-(L-Glu) copolymers were monitored via circular dichroism spectroscopy. HPMA segments confer water solubility and biocompatibility while the L-glutamic acid repeats provide reversible coil-to-helix transitions at endosomal pH values (~5-6). The endolytic properties of these novel [HPMA-b-(L-Glu)] copolymers and their potential as modular components in drug carrier constructs was demonstrated utilizing red blood cell hemolysis and fluorescein release from POPC vesicles.

A facile strategy for control of the polymer topologies can be achieved simply by tuning the feed molar ratio of catalyst to transfer agent in the controlled radical polymerization.

A series of well-defined diblock copolymers, poly(ethylene oxide)-block-poly(4-vinylpyridine) (PEO-b-P4VP) used as physical coating of capillaries, were synthesized by atom transfer radical polymerization (ATRP). EOF measurement results showed that all synthesized PEO-b-P4VP diblock copolymer-coated capillaries in this report could suppress EOF effectively compared to the bare fused-silica capillaries, and efficient separations of basic proteins were achieved. The effects of the molecular weight of P4VP block in PEO-b-P4VP and buffer pH on the separation of basic proteins for CE were investigated in detail. Moreover, the relationships between morphologies of PEO-b-P4VP diblock copolymers in buffer, which were studied by transmission electron microscopy, and the separation efficiencies of basic protein with PEO-b-P4VP diblock copolymers coatings were discussed.

A novel strategy for preparation of multiple nanostructural materials, which is the creation of such materials directly from controlled radical dispersion polymerization in one pot, has been developed. In the formation of polymeric nanomaterials, the chain length ratio of the hydrophobic to hydrophilic blocks is altered continuously, which induces two phase transitions, phase separation to form spherical micelles and re-organization of the resulting spheres to yield multiple morphologies including nanorods, nanotubes, vesicles and doughnuts. This is quite different from self-assembly of the block copolymer in a selective solvent, where nature and solubility parameter of the solvents are changed. In the reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene in methanol using poly(4-vinylpyridine) as macro RAFT agent, the resultant polymeric nanomaterials with various morphologies coexisted generally, however, uniform nanowires and vesicles could be prepared by appropriately selecting concentration of monomer and feed ratio, as well as by strict control of reaction conditions. One advantage of this strategy is that the nanomaterials with a concentration as high as 0.5 g mL−1 can be achieved, this provides possibility for studying extensive applications of the various nanomaterials.

Polymerization-induced self-assembly and re-organization (PISR) was used to prepare polymeric nanostructured materials with a variety of morphologies. Reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene in a selective solvent, methanol, was carried out using cyanoisopropyl dithiobenzoate-terminated poly(2-dimethylaminoethyl methacrylate) (PDMAEMA-DBT) as the macro chain transfer agent and stabilizer for investigation of the factors influencing the formation of morphologies. Various morphologies, including spherical micelles, nanostrings, vesicles and large compound vesicles, with different shapes were obtained by changing the feed ratios and reaction conditions. The sequential morphologic transitions from spherical micelles to nanostrings, to vesicles and to large compound vesicles via increasing the chain length ratio of the hydrophobic block to the hydrophilic one in the same system were observed for the first time. This approach can be performed at a high concentration, thus it can be scaled up for the reproducible preparation of nanostructured materials in a relatively high volume.