Hydrophobically modified ethoxylated urethanes (HEURs) are associative polymers applied as thickening additives in various waterborne systems, such as emulsions, coatings and printing inks. Their conventional synthesis, based on diisocyanates, poses environmental and health threats during both manufacture and application. Hence, in this paper we present an approach for the next generation of sustainable and CO₂-rich polyurethane rheological modifiers – isocyanate-free HEURs (IFHEURs) obtained through poly(hydroxy-urethane) route. The hydrophilic core of the IFHEURs was prepared by step-growth polyaddition between diamine and poly(ethylene glycol) bis(cyclic carbonate) – synthesized using CO₂ as a green source of the carbonate bonds. Such obtained prepolymer with terminal carbonate groups was subsequently modified with hydrophobic amines using reactive extrusion method, which enabled efficient homogenisation of the viscous reaction systems and reaching high end-capping functionality after only 2 h. In contrast to previously reported studies, the synthetic procedure was both solvent- and catalyst-free and allowed to incorporate up to 11 wt% of CO₂ into the backbone of the final products. The structural analysis of the obtained IFHEURs using NMR and FT-IR spectroscopy and MALDI-ToF mass spectrometry confirmed obtaining the desired telechelic architecture resembling standard HEUR materials. The associative behavior of the IFHEURs in aqueous solutions was addressed in a rheological study, which revealed typical thickening mechanisms exhibited by rheological additives.

The study investigated the impact of hard segments (HS) content on the morphology and thermomechanical properties of electrospun aliphatic poly(carbonate-urea-urethane)s (PCUUs). The obtained nonwovens exhibited surface porosity ranging from 50% to 57%, and fiber diameters between 0.59 and 0.71 μm. Notably, the PCUUs nonwovens with the highest HS content (18%) displayed superior mechanical properties compared to those with lower HS contents. This study highlights the ability to customize the properties of polymeric nonwovens based on their chemical compositions, offering tailored solutions for specific application needs.

Meeting the criteria of performance and biocompatibility poses a significant challenge in developing polymeric nonwovens for biomedical and filtration purposes. Although non-isocyanate poly(carbonate-urethane)s (NIPCUs) made by transurethane polycondensation are emerging as non-toxic alternatives to isocyanate-based polyurethanes, their fibrous processing is scarce. Therefore, our work focused on preparing electrospun nonwovens from sustainable NIPCUs with an architecture tailored for high mechanical strength. Combining aromatic 4,4′-diphenylmethane bis(hydroxyalkyl carbamate) hard segments and soft oligocarbonate segments imparted strength and flexibility, while incorporating up to 29 wt % of CO₂ into the structure of the NIPCUs. Scanning electron microscopy showed that adjusted electrospinning parameters produced uniform, submicron fibers without defects. FT-IR and NMR spectroscopy confirmed their unchanged composition and molar mass (20–25 kg mol⁻¹) compared to the unprocessed NIPCUs. Differential scanning calorimetry and dynamic mechanical thermal analysis showed that the macromolecular arrangement induced during electrospinning was strongly dependent on the architecture of the polymer. The mechanical performance of the nonwovens, reaching tensile strength above 5 MPa and elongation at break up to 250 %, correlated to their morphological differences. Thus, appropriate modification of the structure and morphology of the NIPCU nonwovens allowed the production of CO₂-rich submicron fibers with high toughness and flexibility.

Poly(carbonate-urea-urethane) (PCUU)-based scaffolds exhibit various desirable properties for tissue engineering applications. This study thus aimed to investigate the suitability of PCUU as polymers for the manufacturing of nonwoven mats by electrospinning, able to closely mimic the fibrous structure of the extracellular matrix. PCUU nonwovens of fiber diameters ranging from 0.28 ± 0.07 to 0.82 ± 0.12 μm were obtained with an average surface porosity of around 50–60%. Depending on the collector type and solution concentration, a broad range of tensile strengths (in the range of 0.3–9.6 MPa), elongation at break (90–290%), and Young’s modulus (5.7–26.7 MPa) at room temperature of the nonwovens could be obtained. Furthermore, samples collected on the plate collector showed a shape-memory effect with a shape-recovery ratio (R_r) of around 99% and a shape-fixity ratio (R_f) of around 96%. Biological evaluation validated the inertness, stability, and lack of cytotoxicity of PCUU nonwovens obtained on the plate collector. The ability of mesenchymal stem cells (MSCs) and endothelial cells (HUVECs) to attach, elongate, and grow on the surface of the nonwovens suggests that the manufactured nonwovens are suitable scaffolds for tissue engineering applications.

Nature has always been a source of inspiration for the development of novel materials and devices. In particular, polymer actuators that mimic the movements and functions of natural organisms have been of great interest due to their potential applications in various fields, such as biomedical engineering, soft robotics, and energy harvesting. During recent years, the development and actuation performance of electrospun fibrous meshes with the advantages of high permeability, surface area, and easy functional modification, has received extensive attention from researchers. This review covers the recent progress in the state-of-the-art electrospun actuators based on commonly used polymers such as stimuli-sensitive hydrogels, shape-memory polymers (SMPs), and electroactive polymers. The design strategies inspired by nature such as hierarchical systems, layered structures, and responsive interfaces to enhance the performance and functionality of these actuators, including the role of biomimicry to create devices that mimic the behavior of natural organisms, are discussed. Finally, the challenges and future directions in the field, with a focus on the development of more efficient and versatile electrospun polymer actuators which can be used in a wide range of applications, are addressed. The insights gained from this review can contribute to the development of advanced and multifunctional actuators with improved performance and expanded application possibilities.

In recent years, nanoimprinted structures have gained attention due to development of lithographic techniques and molds that enable mass fabrication of a large variety of devices, including optical sensors and biosensors. In this work, one-dimensional photonic crystals (PhC) were nanoimprinted in UV-curable polymer. To enhance interactions between light and medium at PhC surface, optically transparent, high-refractive-index titanium oxide nanocoating with well-defined thickness was deposited on the structure using magnetron sputtering. Since spectral response of PhC varies with optical properties and thickness of layers formed at their surface, they can be used for biosensing applications. In this work we focus on the impact of the nanocoating properties on performance of the optical label-free biosensor. First, the effect of the bound biological material thickness has been studied numerically and experimentally using an incremental atomic layer deposition of aluminum oxide with refractive index reaching 1.6 in the visible spectral range as a reference layer to a biological film. It was shown that there is an optimal thickness of the coating for which the sensing properties (including capability to detect biomolecules of various sizes) are the greatest. Next, using biotin as a receptor and peridinin-chlorophyll-protein conjugated with streptavidin as a target, we have proven that when the nanocoating properties are not optimized for the biomaterial at the sensor surface, sensing capabilities are highly limited.

This work presents an eco-friendly synthetic pathway toward non-isocyanate poly(carbonate-urethane)s (NIPCUs) obtained from carbon dioxide and its simple derivatives─organic carbonates. Bis(hydroxyalkyl carbamate)s synthesized from ethylene carbonate and appropriate α,ω-diamines were used as polyurethane hard segment precursors while oligocarbonate diols as soft segment ones. The structures and properties of the obtained NIPCUs were explored by means of ¹H NMR, ¹³C NMR, and FT-IR spectroscopies, MALDI-ToF mass spectrometry, DSC, and mechanical testing. Based on spectroscopic data as well as model reactions, it was demonstrated that the formation of the urea bonds was suppressed due to the presence of carbonate moieties. The reaction of urea bonds with carbonate residues led to urethane group formation. In addition, the influence of the polyurethane structure on the mechanical and thermal properties of the obtained polymers was studied. The obtained NIPCUs exhibited mechanical properties comparable to conventional polyurethane elastomers (e.g., a tensile strength of 32 MPa and an elongation at break of 800%). The described synthetic route is an straightforward way toward the replacement of conventional polyurethanes with environmentally friendly ones.

The method of preparation of partly degradable asymmetric hollow fiber membranes based on polysulfone/poly(L-lactide-co-glycolide-co-ε-caprolactone) blends (PSf/LGC) is presented. The membrane-forming blends were prepared by mixing two solutions: PSf in N-methyl-2-pyrrolidone and LGC in tetrahydrofuran. Further, PSf/LGC membranes were obtained by a dry/wet-spinning phase-inversion technique and treated with a sodium hydroxide solution using the flowing method. The membrane properties such as hydraulic permeability coefficient (UFC), retention coefficients, and structure morphology were evaluated before and after hydrolysis. An increase in the ultrafiltration coefficient was observed, while the retention coefficient did not change significantly in the case of membranes after post-treatment. The hydrolysis of LGC component in the terpolymer was evaluated by the weight method. Measurements of membrane weight loss before and after the hydrolysis process confirmed the removal of more than 50 wt.% of the LGC component from investigated membranes, resulting in permeability increase due to increased membrane porosity. Fourier transform infrared spectroscopy (FTIR) analysis also confirms significant LGC polymer removal. Furthermore, a computer-aided image processing method was used for investigating the morphology before and after the hydrolysis process. This method verified the changes in membranes’ morphology by the differences of membranes’ porosity. The total porosity of membranes increased from 34% to 38% to 42% after the hydrolysis process.

Porous three-dimensional (3D) scaffolds are promising treatment options in regenerative medicine. Supercritical and dense-phase fluid technologies provide an attractive alternative to solvent-based scaffold fabrication methods. In this work, we report on the fabrication of poly-etheresterurethane (PPDO-PCL) based porous scaffolds with tailorable pore size, porosity, and pore interconnectivity by using supercritical CO₂ (scCO₂) fluid-foaming. The influence of the processing parameters such as soaking time, soaking temperature and depressurization on porosity, pore size, and interconnectivity of the foams were investigated. The average pore diameter could be varied between 100-800 μm along with a porosity in the range from (19 ± 3 to 61 ± 6)% and interconnectivity of up to 82%. To demonstrate their applicability as scaffold materials, selected foams were sterilized via ethylene oxide sterilization. They showed negligible cytotoxicity in tests according to DIN EN ISO 10993-5 and 10993-12 using L929 cells. The study demonstrated that the pore size, porosity and the interconnectivity of this multi-phase semicrystalline polymer could be tailored by careful control of the processing parameters during the scCO₂ foaming process. In this way, PPDO-PCL scaffolds with high porosity and interconnectivity are potential candidate materials for regenerative treatment options.

Structure-property relationships of novel non-isocyanate poly(carbonate-urethane)s (NIPCU) based on a 100% renewable fatty diamine were studied. The polymers were obtained via polycondensation of PRIAMINE 1075-based bis(hydroxyalkyl carbamate) with oligo(decamethylene carbonate) diol. The structure of products was studied using FT-IR and NMR spectroscopies. Urethane-carbonate copolymers showed no presence of urea or allophanate bonds. In contrary to literature reports showing weak mechanical properties for fatty diamine-based poly(ester-urethane)s and poly(ether-urethane)s, our poly(carbonate-urethane)s showed exceptional mechanical properties. Introduction of decamethylene carbonate units into the polyurethane structure combined with the possibility of formation of hydrogen bonds between urethane and carbonate units yielded NIPCU exhibiting high toughness, flexibility, as well as solubility in common solvents. The molar ratio of urethane to carbonate groups in the product was optimized. The best sample (NIPCU_50%) containing equimolar amounts of urethane and carbonate groups (50 _mol%) showed the highest number-average molar mass (43 100 g mol⁻¹) as well as tensile strength of 20 MPa and elongation at break of 1800%.

Polyurethanes are one of the most important groups of polymers for numerous sectors of industry. Their production involves using dangerous components (diisocyanates), thus, in the search for safer synthetic routes, alternative methods yielding non-isocyanate polyurethanes (NIPU) have been investigated. In this study, the synthesis of polyhydroxyurethane from cyclic carbonates was performed. A three-factor, three-level Box–Behnken experimental design was constructed and the reaction time, temperature and reagents’ molar ratio were the independent variables. The built model revealed that the viscosity was influenced by all three independent factors, while the mechanical properties and glass transition temperature of the PHUs were affected by the reagents’ ratios. An experimental verification of the model proved its accuracy as the mechanical strength and glass transition temperature deviated from the modeled values, by 15% and 7%, respectively.

This paper presents a non-solvent and non-isocyanate synthetic route towards the linear aliphatic and aliphatic–aromatic poly(carbonate-urethane)s. As the polyurethane hard segment precursors, urethane diols were applied. These monomers were obtained in two steps. Firstly, the bis(methyl carbamate)s of appropriate diamine were prepared using dimethyl carbonate. Next, the urethane diols were obtained via transurethanization of alkylene or arylene bis(methyl carbamate)s with an excess of 1,5-pentanediol. As a polyurethane soft segment precursor, an amorphous oligo(hexamethylene-co-pentamethylene carbonate) diol was used. The influence of the polyurethane structure on mechanical and thermal properties of the obtained non-isocyanate poly(carbonate-urethane)s was studied. It was found that the presence of pentamethylene carbonate units facilitates removal of the low-molar-mass polycondensation products from the system and decreases the time of reaction needed to gain high-molar-mass polymers. The poly(carbonate-urethane)s were characterized by ¹H NMR, ¹³C NMR, and FT-IR spectroscopies, MALDI-ToF spectrometry, DSC, TGA, GPC, and mechanical testing. The aliphatic poly(carbonate-urethane)s exhibited tensile strengths >40 MPa, while the aliphatic–aromatic ones showed tensile strengths up to 50 MPa. Poly(carbonate-urethane) possessing the 80 wt% of hard segments based on 1,4-diaminobutane displayed comparable mechanical properties to commercially available isocyanate-based poly(carbonate-urethane)s e.g. Bionate® PCU 80A and Carbothane® PC3575A.

In this article we report preparation and characterization of cross-linked non-isocyanate poly(hydroxyurethane) polymeric materials showing energy-dissipating properties. The materials were obtained by the ring-opening polyaddition reaction of hyperbranched multi(cyclic carbonate) (HBPG2) with various diamines. The hyperbranched multi(cyclic carbonate) was obtained in two step procedure including anionic polymerization of glycidol with trimethylolpropane (TMP) as a core yielding polyglycerol (HBPG1) and reaction of terminal vicinal hydroxyl groups of HBPG1 with dimethyl carbonate in the presence of potassium carbonate. HBPG1 and HBPG2 were characterized using various NMR techniques, FTIR and MALDI-ToF mass spectroscopy. Thermal and mechanical properties of elastomers, including dissipated energy capacity have been studied. Analysis of force absorbing efficiency test results showed that synthesized elastomers have the capability to dissipate about 60% of the energy. The energy dissipating properties of obtained poly(hydroxyurethane) elastomers were similar to those of shear thickening fluid materials that are currently used in human body protectors, in vibration damping devices or sound insulations. The article proves that it is possible to obtain advanced engineering materials using environmentally friendly materials.

Polymeric coatings with positive surface charge offer potential antimicrobial activity, which they owe to a simple electrostatic attraction with negatively charged bacterial walls and membranes. We describe synthesis and characterization of poly(2-aminoethyl methacrylate) and its copolymers with methyl methacrylate and butyl acrylate, as potential binders for antimicrobial solvent-cast paints. TiO₂ and CaCO₃ mineral particles were employed as model pigments/fillers, as they are used in most real-life paint formulations. Electrokinetic (ζ) potential and antimicrobial activity of thin films made of the (co)polymers in the absence and presence of TiO₂ and CaCO₃ nanopowders were assessed using streaming current measurements and microbial growth inhibition tests, respectively. Independently of the structure of the monomers used for the synthesis, the films showed positive ζ-potential values (up to +95 mV) in the pH range 3.5-8.0. The presence of mineral particles at 50% dry weight of the films did not affect significantly the ζ(pH) curves. The films made of the mixed dispersions remained positively charged and inhibited growth of both Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria, as well as yeast (C. albicans). The mixed polymeric-mineral films described in this study seem to be promising potential candidates for designing antimicrobial coatings aimed to prevent spreading of bacterial infections.

Hyperbranched polyoxetanes are a relatively new class of polymers. These are branched polyethers that are synthesized from oxetanes—four-member cyclic ethers bearing hydroxymethyl groups—via ring-opening polymerization. Four series of polyoxetanes were synthesized from 3-ethyl-3-(hydroxymethyl)oxetane and 1,1,1-tris(hydroxymethyl)propane as a core molecule. Reagents ratios ranged from 1:5 to 1:50, theoretical molar mass ranged from 714 g/mol to 5942 g/mol, and dispersities ranged from 1.77 to 3.75. The morphology of the macromolecules was investigated by a matrix-assisted laser desorption/ionization time of flight technique. The polyoxetanes’ adhesive interactions with polar materials were analyzed and provided results as follows: the work of adhesion was 101–105 mJ/m², the bond-line tensile shear strengths were 0.39–1.32 MPa, and there was a brittle fracture mode within the polymer. The findings confirmed a good adhesion to polar substrates, but further research on polyoxetane modifications toward a reduction of brittleness is necessary.

In this article we report an easy synthetic route towards hyperbranched polyglycerols (Amm-HBPGs) containing trimethylammonium groups and siloxane or hydroxyl end-groups. Siloxane derivatives of Amm-HBPGs were synthesized in an efficient five-step procedure including an anionic ring opening copolymerization of the phthalimide-epoxy monomer with glycidol, followed by reactions with allyl bromide, hydrosililation with hydrogenheptamethyltrisiloxane, hydrazinolysis of phthalimide groups and quaternization of resulting amine groups with methyl iodide. Hydroxyl derivatives were obtained by quaternization of previously reported aminated HBPG’s with methyl iodide. Polymeric products were characterized using various NMR techniques, FTIR, and elemental analysis. Both Amm-HBPGs were shown to be effective in catalysis of addition of CO₂ to oxirane. The hydrophilic catalysts showed higher efficiency but synthesis of ethylene carbonate was accompanied by formation of small amounts of ethylene glycol. The siloxane-containing catalyst was easily separable from reaction mixture showing high potential in the process of converting carbon dioxide into valuable chemical raw materials.

Increasing antibiotic resistance of several pathogenic microorganisms calls for alternative approaches to prevent spreading of bacterial diseases. We propose to employ for this purpose coatings obtained from positively charged latex dispersions. In this contribution we characterize aqueous mixed dispersions containing TiO₂ or CaCO₃ and methyl methacrylate-ethyl acrylate or styrene-ethyl acrylate copolymers synthesized using a cationic surfactant, cetyltrimethylammonium bromide as an emulsifier. Particle size, electrokinetic (ζ) potential of the mixed dispersions and the resulting thin films, as well as antimicrobial properties of the latter are described. The TiO₂ and CaCO₃ dispersions were stabilised with polyethyleneimine (PEI) and optimum pH for the mixed dispersions were chosen on the basis of ζ-potential measurements. For TiO₂, the maximum ζ = +35 mV was found at pH 7.5, and for CaCO₃, pH was set at 8.2 (ζ = +38 mV), to prevent its dissolution. In most 1:1 mixtures of TiO₂ or CaCO₃ with the cetyltrimethylammonium bromide (CTAB)-stabilised latex dispersions, two distinct particles populations were observed, corresponding to the bare latex and bare TiO₂ or CaCO₃ fractions. Films made of the mixed dispersions remained positively charged and showed antimicrobial activity similar or reduced with respect to the bare polymer films.