Front Cover: Next‐Gen polymers: The cover image shows a schematized version of a uniform, sequence‐defined ABCD quaterpolymer, in which C monomer units lead to intramolecular covalent bridges. This ...special issue of Macromolecular Rapid Communications summarizes recent efforts by the European Network Euro‐Sequences toward the synthesis of such precisely‐controlled macromolecules. Further details can be found in the editorial by Jean‐François Lutz (article number 1700747).
Rewriting data stored on synthetic macromolecules is an interesting feature, even though it is considered as being quite challenging within the area of digital macromolecules. In this context, we ...initially studied a strategy for modifying the position tag of sequence‐encoded macromolecules in a reversible manner. The efficiency of this method, which relies on the orthogonal cleavage of a thioester moiety via aminolysis, was demonstrated by modifying parts of an exemplary sentence. Simultaneously, a novel algorithm was developed to ease the read‐out of macromolecular information by means of MS/MS techniques. This program, Oligoreader, can identify potential information‐containing macromolecules from a series of MS1 spectra, analyze the corresponding MS2 spectra, and finally decode the data. Consequently, the algorithm simplifies the entire read‐out process by avoiding any interference from the operator, which increases the potential for blind sequencing of uniform macromolecules.
The rewriting of information stored on synthetic macromolecules is achieved via the introduction of an editable position tag. The automated read‐out is facilitated by making use of an algorithm that is able to decode large portions of macromolecular information without interference from the operator.
Synthetic chemists have developed robust methods to synthesize discrete molecules, linear and branched polymers, and disordered cross-linked networks. However, two-dimensional polymers (2DPs) ...prepared from designed monomers have been long missing from these capabilities, both as objects of chemical synthesis and in nature. Recently, new polymerization strategies and characterization methods have enabled the unambiguous realization of covalently linked macromolecular sheets. Here we review 2DPs and 2D polymerization methods. Three predominant 2D polymerization strategies have emerged to date, which produce 2DPs either as monolayers or multilayer assemblies. We discuss the fundamental understanding and scope of each of these approaches, including: the bond-forming reactions used, the synthetic diversity of 2DPs prepared, their multilayer stacking behaviors, nanoscale and mesoscale structures, and macroscale morphologies. Additionally, we describe the analytical tools currently available to characterize 2DPs in their various isolated forms. Finally, we review emergent 2DP properties and the potential applications of planar macromolecules. Throughout, we highlight achievements in 2D polymerization and identify opportunities for continued study.
This work aims at the production and characterization of promissory food packaging films based on chitosan (CS), zein (ZN), and poly (vinyl alcohol) (PVA). CS and ZN are biodegradable, biocompatible, ...and extracting from natural-sources and renewable. Although PVA is a synthetic polymer, it is also considered biocompatible and present water-solubility. From binary and ternary macromolecule mixtures based on CS/ZN/PVA, were obtained films solvent-free. In this facet, extrusion of the macromolecule mixture following by a hot compression to acquire the films' solvent-free. The films were characterized by several techniques such as Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), prioritization query based on critical packaging requirements which underwent visual and sensorial (smell), mechanical properties, scanning electron microscopy (SEM), and barrier property analysis. Our findings showed that a higher proportion of ZN led to yellowish films with lower transparency and/or higher opacity. Therefore, PVA high content is interesting for our proposal since it allows films with translucency, handling, absence of rupture, and odor. The mechanical tests showed that the ZN effect is associated with reduced tensile strength, increasing elongation, and Young's modulus. Thus, ZN's presence, even if in a smaller proportion to PVA, allows the formation of more rigid films. The morphological analysis indicates the formation of compact films and homogeneous surfaces. However, films with higher amounts of CS and ZN presented greater roughness, globular clusters' presence, and heterogeneity (films' cross-section) that may have influenced water vapor permeability values and better barrier property due to tortuosity that decreases as the PVA content is increased. This finding can be associated with the higher crystallinity of the film when the film's formulation presents significant CS and ZN concentrations. Finally, we demonstrate the feasibility of using films based on the mixture of CS, ZN, and PVA as proposals for a food pack.
•Combination of biodegradable macromolecules (chitosan, zein and PVA) to obtain films for food packaging.•Films for food packaging were obtained solvent-free through extrusion and hot compression.•The as-obtained films showed a good barrier property.•From design of experiments the effects of each component on properties were evaluated.•The laboratory-scale showed promissory and can be scaled up.
Macromolecules with aggregation-induced emission (AIE) attributes are a class of luminescent materials that display enhanced emission when they are aggregated. They have attracted much attention ...because of their good solubility, processability, high emission efficiency in the aggregated states,
etc.
A large variety of AIE macromolecules have been developed, showing exponential growth of research interest in this field. This review summarizes the design principles and recent synthetic advancements, topological structures, as well as the frontiers of functionalities and potential applications of AIE macromolecules, especially fluorescence sensing, biological applications and optoelectronic applications, with an emphasis on the recent progress. New luminogenic systems without conventional chromophores displaying aggregated state emission are discussed. The highly dense clusters of heteroatoms with lone pair electrons in these systems may serve as the chromophore and are cited as "heterodox clusters". It is expected that the mechanistic insights into the AIE phenomena, based on the restriction of intramolecular motions and structure rigidification, can guide the future design of AIE materials with fascinating structures and functionalities.
A comprehensive review of macromolecules with aggregation-induced emission attributes is presented, covering the frontiers of syntheses, structures, functionalities and applications.
Cover: This issue of the Macromolecular Symposia contains selected papers presented at The 2nd International Conference on Soft Materials (ICSM 2016) that took place in Jaipur, India, from December ...12-16, 2016. The cover is taken from the contribution by Yogita Kumari et al. (DOI 10.1002/masy.201700016).
Sequence‐defined polymers have been the object of many fascinating studies that focus on their implementation in both material and life science applications. In parallel, iterative synthetic ...methodologies have become more efficient, whereas the structure elucidation of these molecules is generally dependent on MS/MS analysis. Here, we report an alternative, simple strategy for the determination of the monomer order of uniform oligo(thioether ester)s. This approach, which relies on random cleavages of ester units within the macromolecular backbone via a basic treatment, enables the swift characterization of these macromolecules without the need for MS/MS. Consequently, this method can be used for decoding any information stored within the primary structure of oligoesters by means of ESI‐ or LC–MS. Finally, we speculate that a range of structurally diverse backbones could be susceptible towards this approach, which could promptly expand the library of chemically sequenceable macromolecules.
A strategy for the determination of the monomer order of sequence‐defined macromolecules by making use of ESI‐ or LC–MS is described. This approach, which relies on the introduction of random chain cleavages within the macromolecular backbone, enabled the rapid chemical sequencing of abiotic macromolecules.
Hyperbranched polymers (HPs) are highly branched three-dimensional (3D) macromolecules. Their globular and dendritic architectures endow them with unique structures and properties such as abundant ...functional groups, intramolecular cavities, low viscosity, and high solubility. HPs can be facilely synthesized
via
a one-pot polymerization of traditional small molecular monomers or emerging macromonomers. The great development in synthetic strategies, from click polymerization (
i.e.
, copper-catalyzed azide-alkyne cycloaddition, metal-free azide-alkyne cycloaddition, strain-promoted azide-alkyne cycloaddition, thiol-ene/yne addition, Diels-Alder cycloaddition, Menschutkin reaction, and aza-Michael addition) to recently reported multicomponent reactions, gives rise to diverse HPs with desirable functional/hetero-functional groups and topologies such as segmented or sequential ones. Benefiting from tailorable structures and correspondingly special properties, the achieved HPs have been widely applied in various fields such as light-emitting materials, nanoscience and technology, supramolecular chemistry, biomaterials, hybrid materials and composites, coatings, adhesives, and modifiers. In this review, we mainly focus on the progress in the structural control, synthesis, functionalization, and potential applications of both conventional and segmented HPs reported over the last decade.
This review summarizes the advances in hyperbranched polymers from the viewpoint of structure, click synthesis and functionalization towards their applications in the last decade.
Acidogenic and aciduric bacteria have developed several survival systems in various acidic environments to prevent cell damage due to acid stress such as that on the human gastric surface and in the ...fermentation medium used for industrial production of acidic products. Common mechanisms for acid resistance in bacteria are proton pumping by F1–F0–ATPase, the glutamate decarboxylase system, formation of a protective cloud of ammonia, high cytoplasmic urease activity, repair or protection of macromolecules, and biofilm formation. The field of synthetic biology has rapidly advanced and generated an ever-increasing assortment of genetic devices and biological modules for applications in biofuel and novel biomaterial productions. Better understanding of aspects such as overproduction of general shock proteins, molecular mechanisms, and responses to cell density adopted by microorganisms for survival in low pH conditions will prove useful in synthetic biology for potential industrial and environmental applications.
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