Amphiphilic co-networks (ACNs) represent a fascinating field of research with regard to their hydrophilic and hydrophobic character. These properties resulting from the network structure make ACNs the perfect material for the transport of small molecules. Consequently, ACNs are often used as a material for soft contact lenses with extended wear. [1]

To achieve such unique properties, it is essential to control the structural composition during the network synthesis. The key to success lies in homogeneity with a defined length and number of monodisperse polymer strands. Studies by Sakai et al. [2] in 2008 set a milestone to establish model networks. The pioneering research is based on the end-linking of two four-armed polyethylene glycol (tetra-PEG) stars by hetero-complementary linking with different reactive end groups.

Based on initial research by Bunk et al., [3, 4] our focus is on the synthesis and characterization of end-functionalized hydrophobic ε-polycaprolactone (tetra-PCL) and hydrophilic polyethylene glycol (tetra-PEG) 4arm stars. In order to get as close as possible to the state of a model network, we pursue several cross-linking strategies. These include two different amide-forming systems consisting of (a) a carboxylic acid-terminated star or (b) an oxazinone-terminated star, each combined with an amine-terminated star, and (c) an ionic-covalent system consisting of imidazole- and bromine-terminated stars. The structure determination of these targets was carried out by NMR-spectroscopy. In addition, several investigations were undertaken concerning the reaction kinetics, the degree of cross-linking and the equilibrium swelling degree.

Recently, a new synthetic strategy utilizing the copper-catalyzed reversible-deactivation radical polymerization (Cu-RDRP) initiated by the adducts of trichloroacetyl isocyanate (TAI) was introducted.¹ This strategy enables the synthesis of unique complex polymeric architectures (e.g. graft copolymers, stars) with unprecedently high chain density. So far, however, the strategy has been applied only to non-polar monomers. Within our current efforts aimed at the preparation of hydrophilic biocompatible polymer-based carriers for biomedical applications, we investigated the applicability of the TAI strategy to the polymerization of water-soluble monomers. In this contribution, the optimization of Cu-RDRP conditions to achieve well-defined polymers will be demonstrated for N-(2-hydroxyproply) methacrylamide (HPMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA). Different polymerization parameters, such as temperature, solvent, catalyst and ligand type, or catalytic system stoichiometry, have been varied to attain branched low-dispersity polymers at high monomer conversions. The developed conditions were then applied to synthesize different complex polymeric architectures, e.g., multi-arm polymeric stars based on a β-cyclodextrin core, that will be used for subsequent end-group modification. The synthesized branched polymers were characterized by ¹H NMR spectroscopy and size-exclusion chromatography with a triple-detection system.

Acknowledgment: The financial support from the Ministry of Health of the Czech Republic (project no. NW24-03-00387) is acknowledged.

The introduction of cross-links into polymer chains influences the physical properties of the polymer material. The extent of this effect depends on the degree of polymer cross-linking. This tunability allows for the creation of polypeptides with a wide range of stiffness and elasticity. To prepare cross-linked synthetic peptides by ring-opening polymerization of N-carboxyanhydride (NCA) monomers, a suitable di-N-carboxyanhydride (di-NCA) cross-linker must be used, the reactivity of which should match that of the monomer(s).
Since α-amino acid derivatives based on glutamic acid and lysine are most commonly used for the preparation of synthetic polypeptides, we investigate the preparation of asymmetric and symmetric di-NCA cross-linkers based on glutamyl-lysine (Glu-Lys) isopeptide, lysyle-lysine (Lys-Lys) dipeptide and glutamyl-glutamic acid (Glu-Glu) dipeptide (Figure 1). The Leuch method of NCA synthesis using different halogenating agents proved to be suitable for the preparation of both asymmetric and symmetric di-NCAs. In order to maintain the stability of the symmetric crosslinkers, the amide bond between an amino acid and various linkers have to be preserved.

Modification of organic compounds through selective B=N for C=C replacement has developed into a powerful approach to produce new materials with intriguing properties. In recent years, we have presented a number of inorganic–organic hybrid polymers and oligomers that feature B=N linkages in the backbone. [1-5] This includes a BN analogue of poly(p-phenylene vinylene) (PPV) [1] and inorganic analogues of polyacetylenes, i.e., poly(iminoborane)s. [2] Here, we present a novel polymer composed of B=N-linked ferrocene units, 1, [3] and related copolymers with additional p-phenylene building blocks 2. [4] Our synthetic approach provides access to a donor–acceptor backbone structure due to the NNBB sequence of the heteroatoms along the chain. Highly valuable insights into the microstructure of the novel metallopolymers as well as into the electronic communication over the π-bond of linear B=N moieties in general are presented. Additionally, we present 1,2,5-azadiborolane as a building block for novel macromolecules as well as an inorganic–organic hybrid polymer, 3, containing the longest inorganic BN chain part to date. [5] Studies of the monomer and the oligomers by X-ray crystallography provided first indication of delocalization of the π-electrons over the BN chain in such species.

Block copolymers have attracted much attention in recent years due to their unique self-assembly behavior that can be useful for the design and preparation of a diverse library of nanostructured materials1. Recent studies have demonstrated that the self-assembly process of the block copolymers can be controlled which can lead to novel optical properties2.
In this study, norbornene-based homopolymers and block copolymers containing macromolecular side chains such as polycaprolactone and polylactide were successfully synthesized by ring-opening metathesis polymerization of their corresponding macromolecular monomers using the third generation Grubbs’ initiator. Macromolecular monomers, such as norbornene-polycaprolactone and norbornene-polylactide, were prepared via Steglich esterification reaction catalyzed by dicyclohexylcarbodiimide and 4-dimethylaminopyridine. In general, block copolymers exhibit relatively low polydispersity index of around 1.1. In addition, the molecular weights of the polymers can be simply controlled by tuning the initial monomer to initiator ratio. The maximum reflectance wavelength of the block copolymer with high molecular weight (Mn = 872 kDa) is at 578 nm which is red-shifted by 160 nm compared to that of low molecular weight ones (Mn = 450 kDa). Binary blend of two block copolymers at varying weight percentages exhibit the maximum reflectance wavelength ranging from 418 nm to 578 nm. The optical and thermal properties of the binary blending system with different weight percentages are currently under investigation.

Fluorinated polymers have attracted significant attention due to their exceptional thermal and chemical stability, hydrophobicity, and insulating properties. In this study, we report the synthesis of fluorine-containing bisphenol compounds with various functional groups, which were subsequently copolymerized with different dienes via cationic polymerization to produce novel heat-resistant resins.
The structures and properties of these fluorinated bisphenol monomers and copolymers were characterized using ¹H NMR, ¹³C NMR, ¹⁹F NMR, and differential scanning calorimetry (DSC). HSQC NMR analysis revealed that the chemical shift at 3.86 ppm corresponds to the methine protons on the fluorinated polymer backbone, while the fluorine atoms exhibit a chemical shift around -64.19 ppm in ¹⁹F NMR spectroscopy. When crosslinked with polyphenylene ether, the vinylbenzyl-functionalized compounds exhibited significantly improved thermal properties, including higher glass transition temperatures (Tg) and thermal decomposition temperatures (Td), compared to their methylmethacryloyl-functionalized counterparts.

Radical Induced Cationic Frontal Polymerization (RICFP) is a self-preserving polymerization technique applicable for different industrially relevant resins like epoxides, oxetanes or vinyl ethers. After an initial and locally limited stimulus (heat or light), an exothermic poly¬meri¬zation is initiated via acidic species. The generated poly¬meri¬zation heat cleaves a thermal initiator into radicals which generate, via a redox reaction with a photo acid generator (e.g. iodonium and sulphonium salts) again the initiating acid. This cycle leads to a curing “wave” wandering throughout the whole resin. As only this first energy input is needed, this makes it a faster and more energy-efficient curing method than the state-of-the-art methods for curing such resins, which often include long curing cycles using autoclaves.
This principle is applied to particle and fiber filled composite1 as well as prepregs2 and filament winding applications.

Conventional methods for synthesizing thermoplastic polyurethanes (TPUs) typically rely on isocyanates and catalysts, both of which present significant environmental and safety risks. To mitigate ecological impact and health hazards, the development of non-isocyanate polyurethanes (NIPUs) is crucial. Polyhydroxyurethanes (PHUs) in particular show great potential due to the low toxicity of the monomers and the relative ease of synthesis, but suffer from slow polymerization kinetics [1, 2, 3] and side reactions that decrease their degree of polymerization (DPn) and materials properties. In particular, DPn values for these materials tend to plateau around 30 and rarely exceed 40 [4].

This study reports a new, rapid PHU polymerization from di-functional monomers achieved without macromonomers, catalysts, or post-condensation reactions [5]. Thanks to the unique reactivity of aromatic cyclic carbonates (ACC) with amines – particularly cycloaliphatic secondary amines (CAA) – model systems give 100% conversion within minutes with minimal secondary reactions. This approach has been successfully extended for the first time to the rapid synthesis of linear PHU chains. A range of difunctional ACC and CAA monomers with diverse chemical structures have been utilized to optimize reactivity, minimize side reactions, and achieve high DPn and molecular weights (Mn). The synthesized PHUs were characterized using nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The highest DPn and Mn obtained were ~220 and ~105,000 g/mol, respectively. These PHUs were subsequently molded into bars and analyzed via thermo-mechanical techniques, demonstrating significant potential for future applications.

The production of plastic is increasing annually and is anticipated to grow exponentially over the next decade. Therefore, a substantial amount of polymer waste, in the form of plastic, accumulates. The development of green polymers is one way to reduce our environmental impact. Using biobased resources as raw materials for polymer synthesis reduces the reliance on petroleum as a raw material [1] while allowing for the production of recyclable and/or biodegradable polymers. Owing to the importance of main-chain cyclic or aromatic compounds in terms of their polymer properties, camphoric acid, derived from the oxidation of natural camphor [2,3] and 1,4-cyclohexanedimethanol, CHDM are among the available biobased monomers of interest. In this work, camphoric acid was polymerized with various diols, including linear diols (ethylene glycol and 1,8-octanediol) and cyclic diols (1,4-cyclohexanedimethanol, CHDM) to produce (co)polyesters with number-average molecular weight values ranging from 4,500 to 14,700 g/mol. We observed that the incorporation of CHDM improved the crystallinity of camphoric acid-based (co)polyesters, as demonstrated by melting peaks in differential scanning calorimetry (DSC) and crystalline peaks in wide-angle X-Ray diffraction (WAXD). Furthermore, optimization studies for poly(cyclohexanedimethylene camphorate) (PCHC) demonstrated that increasing the reaction temperature and extending the reaction duration significantly enhanced both molecular weight and yield. Overall, these polymers demonstrate significant potential for advancing the development of sustainable polymeric materials.

A variety of materials, based on reversible imine formation, have been reported in the literature, including well studied examples such as covalent organic frameworks (COFs), linear aromatic and non-aromatic polymers and their corresponding post functionalized derivatives. [1-3] Various applications have been discussed for such materials, including catalysis, gas storage, sensing, drug delivery, usage in batteries and (opto)electronic devices. [4] Furthermore, linear aromatic imine polymers are a promising candidate in green chemistry, due to the possible recycling under highly acidic aqueous conditions. [5]

In this work, strategies towards reversible imine functionalization of linear, aldehyde moiety containing polymers are reported under solvothermal conditions. As precursor, covalently linked benzodithiophene-bithiophene (BDT-BT) polymers are used. Functionalization with aniline and pyrazine derivatives is carried out to test and tune the (opto-)electronic properties of the obtained material. To establish suitability for application in electronic devices, typical characterization methods such as cyclovoltammetry and UV/Vis measurements are applied in both solution and on thin film. Following the complete characterization of the obtained imine polymers, highly acidic, aqueous conditions allow defunctionalization, therefore testing the reusability of the polymer backbone with various substitution patterns. Naturally occurring aldehyde containing molecules such as benzaldehyde are utilized as mediators during defunctionalization.

The combination of a highly conducting BDT-BT linear polymer and aniline/pyrazine derivative functionalization via imine linkage in this work is expected to yield remarkable (photo-)electronic properties to allow later usage in devices, while still allowing effective (re-)functionalization, tuning the properties and recycling the used materials.

There is a growing interest in aliphatic polycarbonate, which can be attributed to its biocompatibility and resorbable properties. Moreover, the monomer used to produce aliphatic polycarbonates may be bio-based, and various functional groups can be incorporated to control the properties of the resulting polymers. For example, the functional groups can be incorporated to control the polymer structure or to regulate biodegradation. Currently, these aliphatic polycarbonates are primarily studied for biomedical applications¹.
The aim of this study is to develop poly(trimethylene carbonate) (PTMC) coatings in order to investigate their properties. PTMC has a low glass transition temperature and therefore requires a cross-link step to form coatings. To achieve this, we propose to develop copolymers of trimethylene carbonate (TMC) and 5-methyl-5-allyloxycarbonyl-1,3-dioxan-2-one (MAC), using ring-opening polymerization (ROP) with alkali salts as catalysts.² MAC has an allyl function that allows the cross-linking of the copolymer chains via a thiol-ene reaction. However, to obtain a homogeneous coating, the allyl function must be randomly incorporated into the copolymer chain. The formation of random copolymers with controlled copolymerization is the main technical challenge in this study, without the use of metal catalysts. In order to form these random copolymers, we will make a kinetic monitoring of both monomers to identify the optimal conditions. The synthesized copolymers will enable the creation of networks with different densities by varying the molar masses, the monomers ratios and the crosslinking agents.

High-tech fiber reinforced plastics often encounter challenges related to mechanical recyclability. During mechanical recycling, the length and reinforcement of typically inorganic fibres, such as glass, and the integrity of composite materials (polymer matrix + fibres) are significantly reduced. This research work aims to investigate and develop a novel circular approach for fully melt-recyclable fibre-reinforced materials using liquid crystalline polymers (LCPs). The strength of this concept lies in the controlled reduction of polymer-polymer interactions, which ensures that the LCPs:
1. Do not crystallise,
2. Phase separate as droplets from the matrix polymer in the polymer melt, and
3. Elongate and solidify into robust fibrils.
These LCP copolymers, combined with the matrix polymer, form a composite that not only expands the range of applications but also enhances the performance of traditionally lower-performing thermoplastics, such as polylactide (PLA) and recycled polyethylene terephthalate (rPET). The core of this approach involves using phenolic acids, which are naturally occurring in local green waste, as monomeric units. These LCP molecules are subsequently linked together using chain extenders to achieve the desired molecular weight and mechanical properties. Given the distinct processing conditions and chemical interactions of PLA and rPET, the research question for this work package is:
What is the impact of the specific chemical functionalities of natural (semi-)aromatic phenolic acids-derived from blueberry, grape, and asparagus waste on LCP synthesis, (ii) chain extended LCPs, and (iii) melt processability in pure form?

The extensive use of petroleum-derived plastics has raised serious environmental concerns, prompting the urgent need for sustainable alternatives sourced from renewable feedstocks. Among bio-based polymers, polyolefins derived from naturally occurring monomers are particularly attractive due to their versatile properties and potential for large-scale production. Significant progress in this field has been achieved through the use of titanium-based OSSO catalysts, which enable highly efficient and controlled polymerization processes. Titanium is a non-toxic and earth-abundant metal, making it an environmentally friendly alternative to more commonly used transition metals in catalysis.
In this work, we report the stereoselective polymerization of (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) using titanium OSSO complexes with different substituents on the aromatic rings. DMNT is a renewable monomer that can be obtained from citral, a natural compound found in plants like lemongrass. The resulting polymer exhibits high regioselectivity for 1,2-insertion and a highly isotactic microstructure. Due to its elastomeric properties, with a glass transition temperature (Tg) of approximately -40°C, DMNT-based polymers hold potential for flexible and impact-resistant applications.
Furthermore, to fine-tune the material properties, DMNT was copolymerized with other renewable monomers, including β-myrcene and β-ocimene (terpenes), as well as 1-phenyl-1,3-butadiene (1PB) and S-4-isopropenyl-1-vinyl-1-cyclohexene (IVC), derived from natural sources such as cinnamon and perilla plants, respectively. The influence of comonomer composition on the thermal and mechanical properties of the resulting materials was systematically investigated.
This study highlights the potential of titanium-based catalysis in the development of novel bio-based polyolefins, paving the way for more sustainable polymeric materials.

The need to replace oil-based, non-biodegradable polymers is a key global challenge. This research proposes poly(amino acids) as an alternative for use in both every day and advanced materials. Poly(amino acids) are a very useful class of polymer as they are biodegradable, biocompatible and produced from a renewable source. They can offer a range of chemical functionalities and, like proteins, are able to form secondary structures, enabling stable polymer self-assembly. Poly(amino acids) are conventionally created by either the ring-opening polymerisation of N-carboxyanhydrides or through solid phase peptide synthesis. These processes are costly, both in environmental and economic terms. If poly(amino acids) can be produced in an environmentally positive and cost- effective manner they could be widely used to replace plastics in everyday applications. The ring-opening polymerisation of 2,5-diketopiperazine in a non-harmful solvent, such as water could address this gap. This two-step process involves the synthesis of a 2,5-diketopiperazine cyclic dimer from amino acids, and the subsequent ring-opening polymerisation of the 2,5-diketopiperazine to form a poly(amino acid). When a hydrophilic macroinitiator is used to initiate the ring opening polymerisation, an amphiphilic block-co-polymer is produced. The properties of this amphiphilic block-co-polymer can be tailored using alternative macroinitiators, alternative amino acids and varying the ratio of the two to control the molecular weight of the poly(amino acid) block. The resulting series of amphiphilic block-co-polymers could be used as green alternatives in a wide range of real-world applications.

Non-isocyanate polyurethanes (NIPUs) are emerging as sustainable alternatives to traditional polyurethanes (PUs), which are widely used in industries like thermal insulation, coatings, and structural materials but pose serious environmental and health risks due to the toxic chemicals (e.g., isocyanates and phosgene) involved in their production. These chemicals are carcinogenic and harmful to both health and the environment.1
NIPUs, synthesized through processes like cyclic carbonate aminolysis, provide an eco-friendly alternative by eliminating hazardous substances and utilizing CO2 as a cost-effective building block, while maintaining similar performance to traditional PUs.2, 3 Among NIPUs, silicone-based materials show great potential for enhanced thermal stability, chemical resistance, and air permeability compared to conventional PUs and silicone-free NIPUs. These Silicone-modified NIPUs also offer improved adhesion, lower surface energy, and greater flexibility, making them ideal for advanced coating applications.4
In this study, CO2 cycloadditions to epoxides were carried out on structurally distinct epoxy functionalized siloxane compounds (1 and 2) in a high¬ pressure autoclave reactor. The successful conversion of epoxide groups to cyclic carbonates was monitored and confirmed by FT IR and NMR spectroscopic analysis. Subsequently, the synthesized cyclic carbonate functionalized siloxanes were subjected to aminolysis reactions with siloxane containing diamines to yield the corresponding silicone based NIPUs. Importantly, the unique cage like, hybrid organic inorganic structure of 2 can impart improved mechanical, thermal, and chemical properties to these eco friendly polymers, expanding their application range and efficacy.

The necessity for replacing petroleum-based non-biodegradable polymers with natural biomass-derived biodegradable materials is of much concern. Indeed, petroleum-based plastics’ pollution must be reduced, and, moreover, there is a shortage of petroleum-based resources due to a natural constraint on petroleum supplies[1]. Hence, sustainable and renewable alternatives to petroleum-based polymers have become an urgent and critical issue. In this context, biomass feedstocks can be environmentally benign substitutes for petroleum derived chemicals[2,3], among them phenolic compounds derived from widely available biomass sources represent a potential solution to these sustainability issues, providing unique properties to the synthesized polymers[4,5]. Besides, the principles of Green Chemistry often centre around several ideas, including the use of renewable feedstocks, safe and ecologically friendly materials, and atom economy[6]. So, to fulfil many of the Green Chemistry principles, CO2 can be used for the synthesis of a variety of polymers. Indeed, it is a renewable and abundant C1-feedstock. Moreover, it is inexpensive, as it is generated as a waste gas in enormous quantities, and its extreme stability makes it non-toxic and non-flammable[7,8]. Nevertheless, nowadays, the necessity to reduce the amount of CO2 in the atmosphere is an urgent issue to achieve a sustainable society because of global warming and related problems such as abnormal weather, sea level rise, ecological system change, and so on[9]. In this context, the direct synthesis of polymers from CO2 is a hot topic, and therefore, in this work, bio-based polycarbonates have been synthesized from vanillin and syringaldehyde and CO2, with promising thermal and mechanical properties.

The primary objective of this study is to synthesize and characterize expandable polystyrene (EPS) with halogen-free flame retardant additives and to evaluate its flame retardancy performance alongside other critical properties such as mechanical strength, thermal stability, particle size distribution, and homogeneity. To achieve this, various halogen-free flame retardants with different functional groups will be incorporated during the EPS synthesis process.

The research aims to analyze the effects of these flame retardants on the flammability resistance and overall performance of the final EPS product. Special attention will be given to ensuring that while improving flame retardancy, other essential properties of EPS are not compromised. Through systematic formulation development, this study seeks to create a balanced material that combines enhanced flame resistance with optimized physical, mechanical, and thermal properties.

This work contributes to advancing the field of flame-retardant materials by providing a comprehensive understanding of how halogen-free flame retardants influence the synthesis and performance of EPS, promoting safer and more sustainable applications in various industries.

Pyridine and its derivates are aromatic bases that are widely used in various applications. However, due to their great solubility in water and many organic solvents, they are hard to separate and recycle. Thus, incorporation of pyridine moieties into polymers is of considerable interest to increase their recyclability.
Until now, pyridines are incorporated into polymers mainly as pendant groups. Herein, we present a new approach that incorporates the pyridine moiety directly into the polymer backbone. Monomers were prepared using the Hantzsch dihydropyridine synthesis with subsequent oxidation. For the Hantzsch reaction, only renewable starting materials were used. Oxidation of the Hantzsch dihydropyridines was performed using potassium peroxydisulfate, which is fully recyclable by electrolysis. For polymerization of the prepared monomers, two different approaches were investigated: polycondensation and acyclic diene metathesis.