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Amphiphilic rigid backbone polymers are traditionally seemed as one-dimensional (1D) rods and show distinct self-assembly behavior to flexible polymers, but they could hardly adapt morphology-tunable self-assembly by changing their holistic conformation upon external stimuli. In this study, we synthesized a series of amphiphilic homopolymers poly(acetylene azobenzene oligoethylene glycol) (P(AAzo-EGx)) containing conjugated polyacetylene mainchain, azobenzene pendants and oligo ethylene glycol tails in each unit. This comb-like amphiphilic polymer could be treated as two-dimensional (2D) nanoribbons with tunable holistic conformation via meticulous tailoring intrastrand repulsion and interchain π-π interaction of azobenzene pendants by light, temperature, and solvent swelling. P(AAzo-EG2) could self-assemble into large vesicles in ambient, whereas transformed to supramolecular helix bundles (SHBs) at 65 °C as well as depicted by dissipative particle dynamics (DPD) simulation, and then turned into grass leaf-like micelles upon sequential ultraviolet (UV) and blue light irradiation. The three assemblies featured different stacking mode of PAAzo skeletons although showed similar aggregate induce emission (AIE) effect. In this holistic macromolecular chain conformation-induced self-assembly and morphology transformation, temperature influenced the stacking of hydrophobic parts mainly by tuning the torsion of PAAzo skeleton. Certain amount of good solvent played a vital role by swelling of hydrophobic PAAzo skeleton, and helping the movement and rearrangement of azobenzene pendants and polyacetylene mainchains like a lubricant. The length and diameter of SHBs could be tuned by changing EGx tails. This work uncovered a facile strategy to tailor the self-assembly of rigid backbone polymers for fabrication of functional nanodevices. [ABSTRACT FROM AUTHOR]

Introducing a second component is an effective way to manipulate polymerization behavior. However, this phenomenon has rarely been observed in colloidal systems, such as polymeric nanoparticles. Here, we report the supramolecular polymerization of polymeric nanorods mediated by block copolymers. Experimental observations and simulation results illustrate that block copolymers surround the polymeric nanorods and mainly concentrate around the two ends, leaving the hydrophobic side regions exposed. These polymeric nanorods connect in a side‐by‐side manner through hydrophobic interactions to form bundles. As polymerization progresses, the block copolymers gradually deposit onto the bundles and finally assemble into helical nanopatterns on the outermost surface, which terminates the polymerization. It is anticipated that this work could offer inspiration for a general strategy of controllable supramolecular polymerization. [ABSTRACT FROM AUTHOR]

This study presents interesting self‐assembly of peapod‐like micrometer tubes from a planet‐satellite‐type supramolecular megamer, which was constructed through the specific host–guest molecular recognition between azobenzene (AZO)‐functionalized hyperbranched poly(ethyl‐3‐oxetanemethanol)‐star‐poly(ethylene oxide) (HSP‐AZO) and β‐cyclodextrin(CD)‐based hydrophilic hyperbranched polyglycerol (CD‐g‐HPG). A peapod‐like structure with micrometer‐sized tube as the pod and vesicles encapsulated inside as the peas was formed through sequential vesicle entosis, linear association, and fusion processes. Dissipative particle dynamics (DPD) simulations support the structural possibility of the supramolecular peapod formation and its mechanism. UV light irradiation could lead to the disassembly of the peapod‐like structure. This study expands the family of supramolecular polymers and opens a new avenue to develop bioinspired complex hierarchical nanoarchitectures at the microscopic level. [ABSTRACT FROM AUTHOR]

A series of novel amphiphilic brush-dendritic-linear poly[poly(ethylene glycol) methyl ether methacrylate]- b-polyamidoamine- b-poly(ε-caprolactone) copolymers (PPEGMEMA- b-D m- b-PCL) ( m = 1, 2, and 3: the generation number of dendron) were synthesized by the combination techniques of click chemistry, atom transfer radical polymerization (ATRP), and ring-opening polymerization (ROP). The brush-dendritic copolymers bearing hydrophilic brush PPEGMEMA and hydrophobic dendron polyamidoamine protected by the tert-butoxycarbonyl (Boc) groups [D m-(Boc) [ABSTRACT FROM AUTHOR]

• A novel miktoarm terpolymer μ-mPEG-PS-POFPMA was synthesized for the first time. • The hydrophobic block ratio has a great effect on self-assembled superstructure. • Abundant compartmentalized structures were obtained. • An exotic superstructure, perforated stomatoctye, was observed for the first time. • A detailed and systematic ternary phase diagram was concluded. A series of highly ordered morphologies in aqueous solution were obtained by self-assembly of ABC miktoarm terpolymers with mutually immiscible hydrophilic poly(ethylene glycol) monomethyl ether (mPEG), hydrophobic polystyrene (PS) and superhydrophobic poly(1H,1H,5H-octafluoropentyl methacrylate) (POFPMA), which were synthesised by a combination of atom transfer radical polymerisation (ATRP), single electron transfer living radical polymerisation (SET-LRP) and click chemistry. Perforated stomatocytes, raspberry-like micelles, and segmented worm-like micelles, difficult to obtain from linear triblock copolymers, were readily prepared from terpolymers mPEG-arm-POFPMA-arm-PS (denoted μ-EFS). Compartmentalization behaviours of the assemblies were investigated by fixing the length of mPEG but adjusting the ratio of hydrophobic and superhydrophobic segments of the terpolymers μ-EFS, which allows us to establish the correlation between self-assembled morphology and the composition of the terpolymers. The abundant morphological transformation of μ-EFS indicates this type of polymer can serve as a reliable platform for discovery of new self-assembled morphologies with highly ordered superstructures. [ABSTRACT FROM AUTHOR]

• Novel ABC miktoarm star terpolymers were synthesized for the first time. • The morphology can be changed by varying length of hydrophobic chains. • The key factor for morphology are the synergism of two hydrophobic chains. • A special transitional morphology was observed for the first time. Fluorine-containing amphophilic polymers, as well as star polymers, have shown extremely abundant self-assembled morphologies because of microphase separation within the assemblies. Taking advantage of these characteristics, we prepared a series of ABC miktoarm star terpolymers with poly(ethylene glycol) (PEG) as a hydrophilic block, as well as poly(2-ethylhexylmethacrylate) (PEHMA) as a hydrophobic chain. Poly(1H,1H,5H-octafluoropentylmethacrylate) (POFPMA) was chosen as the third segment of terpolymers because of its super-hydrophobic/oleophobic characteristics. The terpolymers were synthesised via atom transfer radical polymerisation (ATRP), single electron transfer living radical polymerisation (SET-LRP) and azide-alkyne Huisgen cycloaddition (click reaction). Herein, we investigated the self-assembled behaviours of nanoaggregates formed by varying the length of POFPMA and PEHMA chains of the terpolymers in aqueous solution. The tunable miktoarm star polymer favoured the transformation of nanoassemblies, from patchy spherical micelles to patchy spherical aggregates, spherical micelles, egg-like micelles, segmented-worm micelles, shuttle-like micelles and vesicles. Interestingly, special discontinuous aggregations arranged into lines were observed, which has been seldom found before. The independent control of both of the hydrophobic parameters of terpolymers enhanced the nanostructures of polymeric assemblies of ABC miktoarm terpolymers, providing a reliable method to explore the compartmentalisation behaviours of soft matter assemblies. [ABSTRACT FROM AUTHOR]

As a promising technique for preparing polymeric materials with novel structures and properties, self-assembly is gaining increasing attentions. The applications of self-assemblies raise the claim of full expression of inherent functions and adequate stimuli-responsive features. Light is an excellent media for the realization of inherent functions, in favor of the communication with external environments. The aggregates self-assembled from polymers with optical functions can bring multifarious optical properties and promising applications. In the assemblies, the emission and fluorescence properties of polymers are dependent on both the aggregation type of the polymers and the aggregation-induced effects including planarization and specific intermolecular interactions. The aggregation-induced optical properties are influenced by external stimuli including pH and temperature, which confer various applications, such as in the areas of bioimaging and optical sensor. When photo-responsive groups with photochromism, photo-crosslink or photo-degradation properties are incorporated into polymers, self-assemblies are able to change their shape and inner structure under light irradiation. Such light triggered property is suitable in application for controllable release of loaded species from assemblies. We also discuss the challenges and developing directions regarding the studies and applications of self-assemblies from polymers with optical properties. [ABSTRACT FROM AUTHOR]

Abstract: Self-assembly behavior of poly(γ-benzyl l-glutamate)-graft-poly(ethylene glycol) (PBLG-g-PEG) in ethanol medium was studied by transmission electron microscopy (TEM), scanning electron microscopy (SEM), laser light scattering (LLS), and circular dichroism (CD). The experimental results revealed that the conformation change of the polypeptide graft copolymer exerts marked effect on its self-association behavior. Spindle-like micelles with polypeptide blocks aligned inside the cores are formed in ethanol solution without denaturant acid. When the denaturant acid is added, the rigid α-helix transforms to random coil, resulting in an aggregate structure change from the spindle-like micelle to large compound micelle. For the large compound micelles, the coiled polypeptide chains and PEG blocks pack randomly within the cores, surrounded by the PEG chains outside to stabilize the aggregates. [Copyright &y& Elsevier]

Abstract: Self-association behavior of polypeptide graft copolymer and its mixture with polypeptide block copolymer and drug carrier capability of the formed micelles was examined. The results gained through fluorescence spectroscopy, transmission electron microscopy and nuclear magnetic resonance spectroscopy revealed that both polypeptide graft copolymer and its mixture with polypeptide block copolymer can self-assemble to form polymeric micelles in aqueous media. The molecular structure of the graft copolymer and blending the graft with block copolymer exert marked effects on the critical micelle concentration and the shape of formed micelles. It was found that the hydrophobic inner core of the micelles formed either by graft copolymer or mixture of graft and block copolymers can act as an incorporation site for the hydrophobic drugs. The drug loading content of the graft copolymer micelles tends to be larger when the content of the polypeptide segments in the copolymer increases. The results obtained from the drug-release studies showed that the drug-release rates are dependent on the chemical nature of the graft copolymer, the composition of the graft and block copolymer mixture, and also the pH value of the release media. [Copyright &y& Elsevier]