Polymers constitute an ubiquitous type of materials and play a leading role in various areas of application, e.g. biomedicine, consumer products, organic electronics or high-performance materials. With the current global issues of health crisis, environmental pollution or depletion of fossil fuels in mind, polymer chemistry is one of the major drivers to deliver solutions for a sustainable development. While polymers feature a broad range of applications at present, research for fundamental developments in polymer chemistry has to be addressed as well. As such, research and understanding of basic principles or novel technologies will foster future developments in polymer science and its application in order to tackle the challenges ahead. The present thematic issue will highlight fundamental studies as well as the latest targets for applied research with a focus on the mentioned challenges.
Graphical Abstract
Scheme 1: Schematic overview of g-CN-embedded hydrogel fabrication and its subsequent photoinduced post-modif...
Scheme 2: Hydrophobic hydrogel via photoinduced surface modification over embedded g-CN nanosheets in hydroge...
Figure 1: a) FTIR spectra of freeze-dried HGCM-vTA, HGCM and HG. b) UV spectra of freeze-dried HGCM-vTA, HGCM...
Figure 2: Scanning electron microscopy (SEM) images of a) HGCM and b) HGCM-vTA in combination with their elem...
Figure 3: a) Equilibrium swelling ratios of HG, HGCM, HGCM-vTA at specified time intervals. b) Thermogravimet...
Scheme 3: Overview of pore substructuring via photoinduced free radical polymerization over embedded g-CN nan...
Figure 4: FTIR spectra of freeze-dried HGCM-PAA, HGCM-PAAM, HGCM-PEGMEMA in comparison with HGCM.
Figure 5: Scanning electron microscopy (SEM) images of a) HGCM-PAA, b) HGCM-PAAM, and c) HGCM-PEGMEMA.
Figure 6: a) Thermogravimetric analysis of HGCM, HGCM-PAA, HGCM-PAAM and HGCM-PEGMEMA. b) Equilibrium swellin...
Graphical Abstract
Figure 1: Overview of the methods available for the synthesis of polysaccharides. For each method, advantages...
Figure 2: Overview of the classes of polysaccharides discussed in this review. Each section deals with polysa...
Scheme 1: Enzymatic and chemical polymerization approaches provide cellulose oligomers with a non-uniform dis...
Scheme 2: AGA of a collection of cellulose analogues obtained using BBs 6–9. Specifically placed modification...
Figure 3: Chemical structure of the different branches G, X, L, F commonly found in XGs. Names are given foll...
Scheme 3: AGA of XG analogues with defined side chains. The AGA cycle includes coupling (TMSOTf), Fmoc deprot...
Figure 4: Synthetic strategies and issues associated to the formation of the β(1–3) linkage.
Scheme 4: Convergent synthesis of β(1–3)-glucans using a regioselective glycosylation strategy.
Scheme 5: DMF-mediated 1,2-cis glycosylation. A) General mechanism and B) examples of α-glucans prepared usin...
Scheme 6: Synergistic glycosylation strategy employing a nucleophilic modulation strategy (TMSI and Ph3PO) in...
Scheme 7: Different approaches to produce xylans. A) Polymerization techniques including ROP, and B) enzymati...
Scheme 8: A) Synthesis of arabinofuranosyl-decorated xylan oligosaccharides using AGA. Representative compoun...
Scheme 9: Chemoenzymatic synthesis of COS utilizing a lysozyme-catalyzed transglycosylation reaction followed...
Scheme 10: Synthesis of COS using an orthogonal glycosylation strategy based on the use of two different LGs.
Scheme 11: Orthogonal N-PGs permitted the synthesis of COS with different PA.
Scheme 12: AGA of well-defined COS with different PA using two orthogonally protected BBs. The AGA cycle inclu...
Scheme 13: A) AGA of β(1–6)-N-acetylglucosamine hexasaccharide and dodecasaccharide. AGA includes cycles of co...
Figure 5: ‘Double-faced’ chemistry exemplified for ᴅ-Man and ʟ-Rha. Constructing β-Man linkages is considerab...
Figure 6: Implementation of a capping step after each glycosylation cycle for the AGA of a 50mer oligomannosi...
Scheme 14: AGA enabled the synthesis of a linear α(1–6)-mannoside 100mer 93 within 188 h and with an average s...
Scheme 15: The 151mer branched polymannoside was synthesized by a [30 + 30 + 30 + 30 + 31] fragment coupling. ...
Figure 7: PG stereocontrol strategy to obtain β-mannosides. A) The mechanism of the β-mannosylation reaction ...
Scheme 16: A) Mechanism of 1,2-cis stereoselective glycosylation using ManA donors. Once the ManA donor is act...
Figure 8: A) The preferred 4H3 conformation of the gulosyl oxocarbenium ion favors the attack of the alcohol ...
Scheme 17: AGA of type I rhamnans up to 16mer using disaccharide BB 115 and CNPiv PG. The AGA cycle includes c...
Figure 9: Key BBs for the synthesis of the O-antigen of Bacteroides vulgatus up to a 128mer (A) and the CPS o...
Figure 10: Examples of type I and type II galactans synthesized to date.
Figure 11: A) The DTBS PG stabilizes the 3H4 conformation of the Gal oxocarbenium ion favoring the attack of t...
Figure 12: Homogalacturonan oligosaccharides synthesized to date. Access to different patterns of methyl-ester...
Figure 13: GlfT2 from Mycobacterium tuberculosis catalyzes the sequential addition of UPD-Galf donor to a grow...
Figure 14: The poor reactivity of acceptor 137 hindered a stepwise synthesis of the linear galactan backbone a...
Scheme 18: AGA of a linear β(1–5) and β(1–6)-linked galactan 20mer. The AGA cycle includes coupling (NIS/TfOH)...
Figure 15: The 92mer arabinogalactan was synthesized using a [31 + 31 + 30] fragment coupling between a 31mer ...
Scheme 19: Synthesis of the branched arabinofuranose fragment using a six component one-pot synthesis. i) TTBP...
Figure 16: A) Chemical structure and SNFG of the representative disaccharide units forming the GAG backbones, ...
Figure 17: Synthetic challenges associated to the H/HS synthesis.
Scheme 20: Degradation of natural heparin and heparosan generated valuable disaccharides 150 and 151 that can ...
Scheme 21: A) The one-step conversion of cyanohydrin 156 to ʟ-iduronamide 157 represent the key step for the s...
Scheme 22: A) Chemoenzymatic synthesis of heparin structures, using different types of UDP activated natural a...
Scheme 23: Synthesis of the longest synthetic CS chain 181 (24mer) using donor 179 and acceptor 180 in an iter...
Scheme 24: AGA of a collection of HA with different lengths. The AGA cycle includes coupling (TfOH) and Lev de...
Graphical Abstract
Scheme 1: Schematic representation of the self-initiated photografting and photopolymerization (SIPGP) of 2-h...
Figure 1: A) Graph showing change in the static contact angle with time on a pristine PCL scaffold with a 500...
Figure 2: A) Optical photograph of an SIPGP-coated sample. B) 3D topography reconstruction of the SIPGP-coate...
Figure 3: A) SEM image of pristine, uncoated PCL MEW scaffolds with a hatch spacing of 150 µm × 200 µm and in...
Graphical Abstract
Figure 1: (a) Schematic representation of the phase stability of a binary mixture based on the free enthalpy ...
Figure 2: Illustration of the relationship between the type of miscibility gap and the temperature dependence...
Figure 3: Schematically pictured phase diagram of a binary mixture composed of a dissolved polymer with a LCS...
Figure 4: Schematic illustration of a thermo-induced swelling behavior of a star polymer composed of responsi...
Figure 5: Schematic illustration of self-assembly of block copolymer amphiphiles in a polar medium.
Figure 6: Schematic comparison of the size and conformation between free polymer chains (a), grafted polymer ...
Figure 7: Comparison of the possible phase diagrams of a polymer in solution with partially miscibility and t...
Figure 8: Selection of polymers exhibiting UCST behavior due to hydrogen bonding (blue) divided into homo- (a...
Figure 9: Part A shows the molecular structure of PDMAPS stars synthesized by Li et al. (left) demonstrating ...
Figure 10: Part A contains a schematic demonstration of conformational transitions of dual-thermoresponsive bl...
Figure 11: Part A pictures zwitterionic brushes grafted from silicon substrates obtaining a nonassociated, hyd...
Figure 12: Part A pictures the UCST phase transition of zwitterionic polymers grafted on the surface of mesopo...
Graphical Abstract
Figure 1: (I) DLS of PPM-NP4, MPM-NP2, PPM-NP4-TPP and MPM-NP2-TPP and (II) TEM of PPM-NP4-TPP and MPM-NP2-TPP...
Figure 2: Representative 31P NMR (top) and 1H NMR (bottom) spectrum of PP3-TPP conjugation product in D2O.
Scheme 1: Synthesis of TPP-based PISA particles based on zwitterionic 2-methacryloyloxyethyl phosphorylcholin...
Figure 3: Penetration of PPM-NP4-TPP and MPM-NP2-TPP micelles and fluorescence intensity profile on (A I, II)...
Figure 4: Growth effects of PPM-NP4-TPP and MPM-NP2-TPP on SW982 spheroids after 3 and 6 days of incubation (c...
Figure 5: Cell viability of SW982 spheroids after 6 days treatment with PPM-NP4, PPM-NP-TPP, MPM-NP2 and MPM-...
Figure 6: Cell localization of PPM-NP4-TPP (I) and MPM-NP2-TPP (II) into (A) mitochondria and (B) lysosomes u...
Figure 7: Cytotoxicity study of PPM-NP4-TPP and MPM-NP2-TPP on SW982 cells in relation to the concentration o...
Graphical Abstract
Figure 1: Structures of azide and alkyne functional molecules and polymers used in the photoinduced CuAAC rea...
Figure 2: UV–vis spectra of CuICl, CuIICl2 and BPNs.
Figure 3: a) 1H NMR spectra of the model reaction between benzyl azide (Az-1) and phenylacetylene (Alk-3) bef...
Scheme 1: Proposed mechanism for photoinduced CuAAC reaction using exfoliated BPNs.
Figure 4: a) 1H NMR spectrum of chain end modified PCL-Anth; b) UV–vis spectra of (azidomethyl)anthracene (bl...
Scheme 2: Synthesis of PS-b-PCL block copolymer via exfoliated BPNs-mediated photoinduced CuAAC reaction.
Figure 5: a) GPC traces of PS-Az, PCL-Alk and block copolymer (Ps-b-PCL) b) 1H NMR spectrum of the block copo...
Scheme 3: Preparation of the cross-linked polymer by CuAAC reaction using multifunctional monomers, Az-3 and ...
Figure 6: a) DSC thermogram of photoinduced synthesis of nanocomposite networks (heating rate: 10 °C/min). b)...
Figure 7: (a, b) TEM images of cross-linked polymer at two different magnifications, c) HAADF-STEM image and ...
Graphical Abstract
Scheme 1: Schematic representation of the polymer synthesis of P1 and P2.
Figure 1: DSC-analysis of the polymers P1 and P2 (second heating and cooling cycle; 20 K/min for heating and ...
Figure 2: DMTA analysis of P1 and P2 showing the transition at around 130 °C due to the reversible π–π intera...
Figure 3: Frequency sweeps of polymers P1 (left) and P2 (right).
Figure 4: Temperature dependent IR spectra of P1 drop casted on KBr in the C=C (1570–1605 cm−1) and C=O stret...
Figure 5: Schematic representation of the first healing of P1 at 150 °C.
Graphical Abstract
Figure 1: Schematic representation of the process of aqueous cryogel formation, using (a) monomers/small mole...
Figure 2: Microarchitecture of gelatin cryogels. (A) Surface and cross-sectional SEM micrographs of highly po...
Figure 3: Principle of 3D-cryogel printing. A) Illustration of 3D-printing of cryogels. B) Illustration of th...
Figure 4: Illustration of the production of the injectable multifunctional composite, comprised of alginate c...
Figure 5: Digital and SEM photographs of PETEGA cryogel at 20 °C (top) and 50 °C (bottom), synthesised via UV...
Figure 6: Cell morphology of T47D breast cancer cells cultured in HA cryogels. (A) Schematic representation o...
Figure 7: Preparation of PDMA/β-CD cryogel via cryogenic treatment and photochemical crosslinking in frozen s...
Figure 8: (A) Healing rate of wounds treated with autoclaved CG11 cryogels and those treated with 70% ethanol...
Figure 9: In vivo haemostatic capacity evaluation of the cryogels. Blood loss (a) and haemostatic time (b) in...
Graphical Abstract
Figure 1: Schematic representation of the chemical structures of BTU and BTP and the supramolecular self-asse...
Figure 2: cryoTEM images of A) BTU DAC (10 min, 1,000 rpm) and C) BTP DAC (10 min, 1,000 rpm). The correspond...
Figure 3: AF4 elution profiles showing the stability against dual centrifugation over different time ranges a...
Figure 4: AF4−UV elution profiles after US for the cumulated time of 0 s (black), 1 s (red), 5 s (blue), 10 s...