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Abstract: The phase behavior of coil-comb copolymers A–(B m+1C m ) (side chain number m = 1–5) is investigated by real-space self-consistent field theory (SCFT). Depending on the copolymer composition and architecture, eight two-dimensional ordered phases are observed, including two-color lamellae (LAM2), three-color lamellae (LAM3), hexagonal cylinders (HEX), core–shell hexagonal phase (CSH), hexagon outside hexagonal phase (HEX2), two interpenetrating tetragonal phase (TET2), lamellae with beads inside (LAM + BD), and lamellae with core–shell beads (LAM3 + CSB). When the volume fractions are comparable, i.e., f A ≈ f B ≈ f C, LAM_3 phase is found to be stable for m = 1 while the hexagonal phases (core–shell hexagonal phase CSH or hexagon outside hexagonal phase HEX2) are stable if m > 1. The phase region of the hexagonal phases HEX, CSH or HEX2 enlarges with increasing m. For short coil length, such as f A = 0.1, the phase diagram is complex, especially when m = 1. For longer coil length, the lamellae become the dominant phase. The phase transition from lamellar phase to hexagonal phase is observed with the increase of the side chain length when the side chain number m is large, which is in agreement with the experimental results. Our results give a good way to tailor the phase behavior of block copolymer and are very useful to further study the hierarchical structure of the coil-comb block copolymer. [Copyright &y& Elsevier]

Abstract: The self-assembly of amphiphilic AB diblock copolymer in solution with different molecular size was investigated by using the self-consistent field theory (SCFT). By continuously varying the solvent size and the polymer concentration, the phase diagram is constructed. The aggregate concentration of the amphiphilic AB diblock copolymer decreases in solution with larger solvent size. The phase will transit in solution with different solvent size due to the excluded volume interaction effect. This widely existing excluded volume effect is very useful for the separation of polymers and helpful for understanding the crowding effect in bio-molecules. [Copyright &y& Elsevier]

Abstract: The morphology and the phase diagram of the ABC block copolymer on the polymer-coated substrate were studied by using the self-consistent field theory. Due to the asymmetric surfaces for the block copolymer thin film, the rich hetero-structures occur, which are the combination of two different microstructures, such as perforated lamellar and lamellar phase (PL + L), cylindrical and lamellar phase (C + L). The phase diagrams were constructed for the identical interaction parameters case and the non-frustrated case. The effect of the film thickness is also considered at the fixed grafting density. Comparing the results, we found that the essence of the variation of the grafting density is the change of the effective film thickness in most cases. The relationship between the grafting density and the film thickness is constructed. Our results offer another way to tailor the phase behavior of the block copolymer thin film and obtain the hetero-structures on nanoscale. [ABSTRACT FROM AUTHOR]

Abstract: A real-space implementation of the self-consistent field theory (SCFT) has been used to study the morphologies of ABCD 4-miktoarm star block copolymers. For the sake of numerical tractability, the morphologies and the phase diagrams of ABCD 4-miktoarm star block copolymers are investigated in two dimensions (2D) by varying the volume fractions of the blocks and the interaction parameters. Many interesting and complex morphologies occur and compared with ABCD linear block copolymers; ABCD 4-miktoarm star block copolymers have more regular disciplines. We found that systems with similar components have similar morphologies and at the weaker segregation, the minority components always cannot separate from the other blocks and they easily dissolve to form one phase with other block(s), but with the increase of the segregation degree (large ), the ordered phases can be well separated. With the help of our computational prediction, experimental researchers can work more purposefully and efficiently. [Copyright &y& Elsevier]

Abstract: The order to disorder transition of comb copolymers A m+1B m is investigated by the self-consistent field theory. Although there are only two components in a molecule, the side chain number m affects the phase diagram largely due to the fact that the architecture of a comb copolymer is not invariant under the interchange of A- with B-monomers. With the increase of the side chain number, the interaction (Flory–Huggins) parameter of the order-to-disorder transition (ODT) increases at the same composition and the lowest ODT occurs at the smaller volume fraction of the main chain f A. The influences of the side chain density and the side chain length on the phase behavior were discussed in detail. The relation exists with the fixed main chain length. The comb copolymer with the large side chain number m and the long main chain sections (or short side chain) is more stable. The results are helpful to design nano- or bio-materials with complex architecture or tailor the phase behavior of comb copolymers. [Copyright &y& Elsevier]

The functionalization of telechelic star polymers (TSPs) bears the opportunity to obtain many different supramolecular structures and respective dynamic responses by controlling well-defined parameters such as the properties of functional groups, the arm number of the stars, the polymer flexibility. Hence, we employ both multiparticle collision dynamics and molecular dynamics simulations to investigate the self-organized network structures of TSPs by varying end-attraction strength, arm number, attractive end-group size and polymer flexibility. The equilibrium properties of end-functionalized TSP suspensions have been investigated. The structural properties change abruptly in the vicinity of end-attraction strength ε LJ = 3.5 k B T for flexible TSPs and ε LJ = 3 k B T for semiflexible and rigid TSPs. The coordination number is defined as the number of end-beads in close proximity of each other. The distribution of the coordination number is more uniform and narrower for stronger end-attractions. The coordination number decreases and the number of free end-beads increases with the increase of arm number for relatively rigid TSPs, and the diffusivity decreases as arm number increases. The coordination number increases with increasing attractive end-group size, while the number of free end-beads decreases. Finally, we find the semiflexible and rigid TSP suspension systems are anisotropic ones for strong end-attractions, relatively small arm numbers and big end-group sizes. We suppose this work could lead experimental researchers to design and develop new biological materials with complex architectures. Image 1 • Multiparticle collision dynamics and molecular dynamics simulations are employed. • Structural properties of telechelic star polymer suspensions are investigated. • The network structures are affected by end-attraction strength, arm number, etc. [ABSTRACT FROM AUTHOR]

Copolymerization is a powerful strategy for regulating the performance of materials, but it is still a challenge of in-situ electrochemical co-deposition for homogeneous thin films, mainly due to activity difference of electrochemical precursors. Herein we reported an electrochemical co-deposition from a pair of designed precursors combined luminescent OCBzC and additive E−3-Cz. Although the electrochemical activity of E−3-Cz is much higher than OCBzC, the co-deposition exhibits as a well linear growth remarkably, which produce the cross-linked thin films with enhanced luminescence and carrier mobility. The deposition rate of co-deposition is more than 2 times of OCBzC only. The copolymerization effectively makes film more compactness with refractive index increased from 1.742 (OCBzC only) to 1.763 (copolymers) and the hole mobility increased from 4.8 × 10−8 cm2 V−1 S−1 (OCBzC only) to 1.1 × 10−6 cm2 V−1 S−1 (copolymer). All the results exhibit potential applications of electro-copolymerization film in the field of electroluminescence and display. The copolymerization of OCBzC and E−3-Cz effectively makes film more compactness and exhibits higher hole mobility and fluorescence, which demonstrates the potential applications of electro-copolymerization film in the field of electroluminescence and display. Image 1 • Electrochemical co-deposition from a pair of designed precursors combined luminescent OCBzC and additive E−3-Cz. • The copolymerization effectively makes film more compactness and exhibits higher fluorescence and hole mobility. • Organic emitting-light diode based on copolymerized films exhibits lower work voltage and higher power efficiency. [ABSTRACT FROM AUTHOR]

Two monomers o -( m -triphenyl)-terephthaloyl chloride (TPH1-COCl) and m -( m -triphenyl)- isophthaloyl chloride (TPH2-COCl) with bulky pendant groups were prepared, and they were polymerized with p -phenylenediamine (PPD) or copolymerized with PPD and terephthaloyl chloride (TPC) to prepare aromatic polyamides which were named TPH1 polymer and TPH2 polymer, respectively. The structures of the monomers with bulky pendant groups and the polymers were characterized by 1 H NMR and gel permeation chromatography. The resulting polymers are soluble in some organic solvents such as N -methyl-2-pyrrolidone. However, the solubility of the two series of polymers was different due to the different structures of the two monomers, and it is affected by the feeding ratio of the monomers. Both kinds of polymers have good thermal stabilities with 5% weight loss temperatures close to 500 °C. And glass transitions of some TPH2 polymers were observed. Most of these polyamides show lyotropic liquid crystalline (LLC) behaviors as evidenced by polarized light microscopy results. And the LLC properties are influenced by the structures, molecular weights, and concentrations of the polymers. [ABSTRACT FROM AUTHOR]

Abstract: Nanofiltration (NF) membrane process has become increasingly attractive due to their unique characteristics to selectively remove specific compounds or ions. The most commonly NF membranes are negatively charged which is unsuitable for hardness removal. Therefore, the development of novel NF membranes with a positively charged skin has become a key issue for low pressure water softening. In this study, dual layer microporous hollow fiber membranes were fabricated using Torlon poly(amide-imide) (PAI) as the material of the selective outer layer and polyethersulfone (PES) as the material of the porous support inner layer. A positively charged NF-like selective layer was developed by a simple polyelectrolyte cross-linking using polyallylamine (PAAm). The newly developed (PAI–PAAm)–PES dual layer hollow fiber membranes show a salt water permeability of 15.8 L/m2 h bar and high Mg2+ and Ca2+ rejections of 94.2% and 92.3%, respectively, at operating pressure of 2 bar using a 3000 ppm TDS feed solution. This study provides a simple and effective approach to produce positively charged NF hollow fiber membranes for water softening applications with low energy consumption. [Copyright &y& Elsevier]

Abstract: Fluorescent glycopolymers were prepared via combined atom transfer radical polymerization (ATRP) and ‘Click Chemistry’ in one-pot synthesis, in the presence of 2-azidoethyl methacrylate (AzEMA), 2-propynyl α-d-mannopyranoside, N,N′-bis{2-[2-[(2-bromo-2-methylpropanoyl)oxy]ethoxy]ethyl}perylene-3,4,9,10-tetracarboxylic acid bisimide (PBI-Br), copper (I) bromide catalyst and pentamethyldiethylenetriamine (PMDETA) ligand. Simultaneous ATRP and ‘Click Chemistry’ is an attractive method for the synthesis of functional glycopolymers as the reaction conditions are compatible with ATRP of an azide monomer, as long as an alkynyl-functionalized carbohydrate is available for click coupling reaction. The fluorescent glycopolymers were characterized by 1H NMR, FT-IR, UV–visible absorption, fluorescence and X-ray photoelectron spectroscopies, as well as by gel permeation chromatography. Incubation of Escherichia coli (E. coli DH5α) with the fluorescent glycopolymers yielded green fluorescent bacterial clusters. The low cytotoxicity level of the fluorescent glycopolymers was revealed by incubation with 3T3 fibroblasts, macrophages and KB cells in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays in vitro. Subsequently, the water-soluble, biocompatible and fluorescent glycopolymers were used as effective fluorescent cell labeling agents. [Copyright &y& Elsevier]

A systematical calculation is performed to explore the equilibrium phase behaviors of linear-dendritic triblock copolymer A B ( 2 g + 1 − 2 ) C 2 g + 1 ( g is the generation number of the block B, and G g is short for A B ( 2 g + 1 − 2 ) C 2 g + 1 ) from G1 to G5 by using self-consistent field theory. Eight phases are found: two-colored lamellar phase, three-colored lamellar phase, hexagonal phase, core shell hexagonal phase, tetragonal phase, core shell tetragonal phase, two interpenetrating tetragonal phase, lamellar phase with beads except disordered phase, by varying the interaction parameters between different blocks, the volume fractions of the blocks and the generation number. While investigating the effect of linear coil length on morphology, we find the longer linear length ( f A = 0.5) for G1, G2 can be beneficial to form the lamellar phase, however, tend to form hexagonal phase easily with generation number increasing from 3 to 5, and short linear length ( f A = 0.2) can be better for inducing hexagonal phase from G1 to G5. It becomes more and more difficult to phase separate with generation number increasing from 1 to 5 due to the architectural complexity. However, increasing the interaction parameters is helpful to facilitate phase separation. It is likely to offer new opportunity for designing nanomaterials and applying to template technology by finely controlling the dendron generations, length of the linear chain, interaction parameters of linear-dendritic triblock copolymers. [ABSTRACT FROM AUTHOR]