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High molecular weight (HMW) poly(butyl acrylate)s (PBAs) and diblock copolymers consisting of PBA blocks were synthesized by ab initio emulsion polymerization using water-soluble organotellurium ch...

We report the synthesis of a bottlebrush statistical copolymer (BSCP) architecture and its role in directing molecular packing in the bulk state. Copolymers with a statistical distribution of two c...

High-temperature thermal gradient interaction chromatography (HT-TGIC) can be used to measure the chemical composition distribution of ethylene/α-olefin copolymers using a column packed with porous...

Herein, we report on an advanced design for polymer electrolytes (PEs) based on our previously reported microphase-separated poly(vinyl benzyl methoxy poly(ethylene oxide) ether)-block-polystyrene block copolymers (PVBmPEO-b-PS). Usually, such block copolymers are characterized by a high mechanical stability provided by the PS domain, while the PEO-based domain features decent ionic conductivities, however, mostly only at higher temperatures. To enable suitable ionic conductivities at lower temperatures, we selectively implemented two ionic liquids (ILs) as a model plasticizer for the PEO domain. Since those ILs are nonmiscible with PS, the latter domain is unaffected, thus still providing a great mechanical stability. To maintain the necessary self-standing film forming ability, we adjusted the size of the PS domain to match with the conducting PEO-based domain. For this, a series of four block copolymers with different PS:PVBmPEO block ratios were synthesized, thus enabling the study of the influence of different amounts of IL. Further, all derived polymer electrolytes were thoroughly characterized by thermal, rheological, morphological, and electrochemical analyses. We could prove the microphase-separated morphology with long-range order and a good thermal and mechanical stability as well as the selective mixing of the ILs within the conducting domain. Consequently, electrochemical impedance spectroscopy revealed a significant increase in ionic conductivity up to 2 orders of magnitude and a reduced interfacial resistance in comparison to a nonplasticized reference sample. Moreover, exhaustive studies of the lithium-ion transference number showed not only the importance of such detailed analysis for IL-containing PEs but also the true increase of the effective lithium-ion conductivity. Finally, we conducted a full cycling in Li||LiFePO4 (LFP) cells to clearly demonstrate the applicability of our approach.

The financial support of the National Natural Science Foundation of China (52022031, 21734004, 21971075) and the Fund of Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates (2019B030301003) is acknowledged.

We present the design, synthesis, and characterization of triple hydrogen-bond-forming precursors and their supramolecular triblock copolymers. Thymine end-functionalized polystyrene-b-polyisoprene...

The determination of the block sequence of triblock copolymers is difficult without information on the synthetic conditions, such as starting materials and reagents used or analysis using tandem ma...

Ethylene–vinyl alcohol copolymers (EVOHs) are important materials available in a variety of compositions and valued in countless applications. In spite of their great adaptability offered by the ad...

A class of heteroatom polymers through anionic chain growth copolymerization of epoxides and isothiocyanates has been successfully obtained under mild conditions via initiation by a simple salt of ...

Monodisperse polymers composed of a discrete number of repeating units have attracted considerable interest as model systems to investigate the behavior of polymers having chemical structures witho...

The synthesis of ethylene/myrcene copolymers was performed using half-titanocene catalysts in the presence of a methylaluminoxane (MAO) cocatalyst. Cyclopentadienyl-phenoxide catalysts, Cp*TiCl2(O-...

High-performance piezoelectric polymers are promising for a broad range of practical applications, such as sensors, actuators, and energy generators in medical devices, wearable electronics, and so...

We report results from Monte Carlo field-theoretic simulations (MC-FTS) of a compositionally asymmetric diblock copolymer melt (fA = 0.2) at an invariant degree of polymerization of N = 104 for bo...

Herein, we report on a new and innovative post-polymerization modification procedure for the ethylene-free synthesis of polyethylene copolymers and block copolymers. Poly[N-(acryloyloxy)phthalimide...

We describe how the organocatalytic, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-based lactide ring-opening polymerization can be effectively performed in a very polar solvent, N-methylpyrrolidone (NMP). Due to a low ceiling temperature, this “living” mechanism has been unreported to date, but we here demonstrate that through a combination of low temperature and repeated monomer additions (starve-fed process), this mechanism enables the generation of a plethora of multifunctional homo- and (stereo)block-poly(lactide)s (PLAs) with exquisite control of the molecular weight dispersity (typically Đ < 1.1) and topology (from linear through 4-, 6-, or 8-armed stars and up to ∼140 armed combs). They are scarcely obtainable or inaccessible through more classical synthetic methods due to the poor solubility of multifunctional initiators (polyols) in most organic solvents and monomer melts. In these precisely designed structures, branching significantly altered the nature of the materials’ hydrolytic degradation, allowing them to acquire a pronounced surface character (as opposed to the bulk degradation of linear polymers). Finally, we have assessed the amenability of this method to in situ block copolymerization by using the tacticity of PLLA blocks in PLLA-b-PDLLA versus PDLLA-b-PLLA (L-LA polymerized before or after DL-LA) as a sensitive method to detect (stereochemical) defects.

The microstructure of physically assembled gels depends on mechanical loading and environmental stimuli such as temperature. Here, we report the real-time change in the structure of physically assembled triblock copolymer gels that consist of 10 wt% and 20 wt% of poly(styrene)-poly(isoprene)-poly(styrene) [PS-PI-PS] triblock copolymer in mineral oil (i) during the gelation process with decreasing temperature, (ii) subjected to large oscillatory deformation, and (iii) during the stress-relaxation process after the application of a step-strain. The presence of loosely bounded PS-aggregates at temperatures higher than the rheometrically determined gelation temperature (Tgel) captures the progressive gelation process spanning over a broad temperature range. However, the microstructure fully develops at temperatures suciently lower than Tgel, and the storage modulus (G0 ) also reaches a plateau at those temperatures. The microstructure orients in the stretching direction with the applied strain. In an oscillation strain cycle, such oriented structure has been observed at low-strain. But, at large-strain, the oriented structure splits, and only a fraction of midblock participates in load-bearing. This has been attributed to the endblock pullout from the aggregates, likely caused by the strain localization in the samples. Both microstructure recovery and time-dependent moduli during the stress-relaxation process after the application of a step-strain can be captured using a stretched-exponential model. However, the microstructure recovery time has been found to be two orders of magnitude slower than the stress-relaxation time at room temperature, indicating a complex nature of relaxation process involving midblock relaxation, endblock pullout and reassociation process. Due to their viscoelastic nature, these gels' mechanical responses are sensitive to strain, temperature, and rate of deformation. Therefore, insights into the microstructural information as a function of these parameters will assist these gels' real-life applications and design new gels with improved properties

Rapid and reliable processing methods for forming ordered block copolymer (BCP) materials with low defect density in a thin film geometry are required for many nanotechnology applications. Vertical...

A comprehensive range of fourteen synthetically simple, air-stable and structurally diverse Fe(III) complexes, comprising of salalen, salen, salan and thiolen frameworks, were applied as catalysts to the ring opening copolymerization of phthalic anhydride (PA) and cyclohexene oxide (CHO) without the need for extra additives, such as co-catalyst, as part of a newly discovered unary system. Alternating poly(1,2-cyclohexylene-1,2-phthalate) {poly(CHO-co-PA)} was obtained with reasonable molecular weights, narrow dispersities and with high % ester linkages. Structure-activity-relationships have been investigated and discussed. The most interesting discovery was when performing ‘ligand control’ ROCOP experiments (highlighting the importance of such checks in catalysis) that all these organocatalysts outperformed their Lewis acidic Fe(III) analogues; these results are significant as a simplistic, metal- and halide-free, organocatalytic single component approach to ROCOP was developed. There are few examples of organocatalysts in literature, examples tending to rely on two component systems with harsher, air-sensitive chemicals and these results provide hope that more reactive, effective organo-initiators are possible in an area very much in its infancy, but will no doubt emerge and potentially prove vital to future sustainable polymerization research. Thermal properties were accessed via DSC analysis and, for the amorphous copolymers, the Tg values ranged by 35 °C from 100 °C to a respectable 135 °C.

This work was supported by King Abdullah University of Science and Technology, grants REP/1/3848-01-01, URF/1/4040-01-01 and base lines.

A series of bio-based comb-like polymers with various lengths of alkyl chains were synthesized through combining the ring-opening copolymerization of sustainable CO2 with bio-renewable castor oil-d...