Polymer International最新文献

3D printing technology is widely used in several fields due to its design flexibility in the preparation of complex geometries. However, conventional 3D printing techniques make it difficult to directly construct polymeric materials with nanoscale structures, which are critical for areas such as adsorption, separation and tissue engineering. In this study, a method combining digital light processing 3D printing with polymerization-induced phase separation is proposed for the preparation of 3D objects with nanoporous structures. Without designing macroscopic pores, the porosity of 3D objects prepared by this method can reach 20%–30%, and efficient processing of complex structures can be achieved. Moreover, the controllability of nanopores was systematically investigated from both molecular weight and concentration dimensions by adding polyethylene oxide (PEO) and polyvinylpyrrolidone (PVP) as synergistic porogens in the ink. The results showed that low molecular weight PVP is able to significantly increase the pore number and distribution uniformity with increasing concentration. Among the products, ZK/PVP_6wt% showed the best effect. High molecular weight PEO can effectively enlarge pores under low concentration conditions (ZK/PEO_2wt%), but, as the concentration increases, its solubility in water limits further optimization of pore structure. The above methods enable flexible regulation of the application scope of 3D printing in structural features ranging from nanometer to centimeter scales, demonstrating broad application potential in fields such as adsorption and separation. © 2025 Society of Chemical Industry.

Small particle size is an important parameter for minimized aggregation, improved cellular uptake and biocompatibility. Nanoparticle size can be controlled by the method used during synthesis. Cationic chitosan nanoparticles (CNPs) are advantageous for endosomal escape; however, obtaining micrometer-sized nanoparticles and formation of aggregates during the gelation process reduce cellular uptake. Probe sonication is a technique used to reduce the nanoparticle size, which is determined by various factors, the most important one being the amplitude. In this study, two amplitudes were used to synthesize and characterize CNPs in terms of their size, release, toxicity and cellular internalization successes. The one with superior characteristics was chosen to produce CNPs to be loaded with methotrexate (MTX), an anticancer agent. The endosomal escape and effectiveness of CNPs was tested in cervical cancer cells (HeLa). The size of nanoparticles was below 200 nm. The release was slower, and cellular internalization was higher in CNPs synthesized with lower amplitude. The encapsulation efficiency was 82% and MTX was released for 5 days. CNPs significantly increased the efficacy of MTX which was attributed to efficient internalization and successful endosomal escape. These findings reveal that synthesized MTX-loaded CNPs may be used as an alternative treatment strategy for cervical cancer with possible lower side effects. © 2025 Society of Chemical Industry.

For many years, laminated safety glass based on poly(vinyl butyral) (PVB) has been widely used in the fields of construction and transportation. In recent years, functional and intelligent laminated safety glass has attracted more and more attention. Laminated safety glass with adjustable refractive index has application value in optical communication and photoelectric switch lights. In this work, as a representative chromophore, disperse red 1 (DR₁) was blended with PVB solution, and then PVB/DR₁ film was prepared by spin coating. Based on this, laminated safety glasses have been constructed by hot processing after high-voltage polarization. The refractive index of the laminated glass can be increased from 1.46 to 1.474 by controlling the polarization voltage. This will have important applications in military and defense industries, laser lenses and other fields. © 2025 Society of Chemical Industry.

Poly(lactic acid) (PLA) modified by addition of the ionic liquid (IL) 1-butyl-1-methylpyrrolidinium hexafluorophosphate was processed by extrusion followed by 3D printing to obtain (PLA + IL). The presence of the IL enhances polymer chain mobility, increasing its fluidity. Variation of storage and loss modulus with strain percentage indicates that the presence of the IL additive reduces strain resistance, decreasing the viscoelastic properties. Reciprocating tribological tests have been carried out on the high-roughness surfaces of as-printed PLA and (PLA + IL), under sliding parallel and perpendicular to the 3D printing direction. The addition of IL reduces friction coefficients with respect to unmodified PLA, shifting the transition to high-steady-state friction to longer distances for (PLA + IL). The highest average friction reduction (45%) is observed for sliding perpendicular to the 3D printing direction. This effect is attributed to a better layer adhesion in (PLA + IL). Surface damage is studied by profilometry and scanning electron microscopy. A very mild polishing effect with unmeasurable wear is observed on the wear paths. Short-term degradability studies of 3D printed films in seawater indicating differences between both materials have been carried out. © 2025 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

In the present study, we explored the composition of an epoxy, melamine and cenosphere surface modified by using 3-aminopropyltriethoxysilane (APTES) as a hybrid filler and improved interfacial bonding. We analysed the structure, morphology, mechanical and tribological, thermal conductivity. XRD confirmed a transition from amorphous to semicrystalline phases of the epoxy composite. The chemical structure observed by Fourier transform infrared spectroscopy exhibits a peak at 2930 cm⁻¹, indicating CH stretching and covalent bonding due to APTES, mutually supported by Raman spectroscopy. Improved filler distribution and reduced porosity were foreseen by SEM. A reduction in void content by 10%–12% was observed as a function of hybrid filler loading, confirmed by density measurements. There was a threefold increase in Shore D hardness (for 15 wt% hybrid filler) and increased tensile strength, 213 N (virgin epoxy) to 931 N (20 wt% hybrid filler). Increased thermal conductivity by 73%, with excellent heat diffusion, was confirmed by Lee's disc. A pin-on-disc tribometer demonstrated (67%) decreased specific wear rate compared to the virgin epoxy. This investigation may be deployable for the automotive and aviation domains as an emerging composite. © 2025 Society of Chemical Industry.

In this work the drying behaviour of the system toluene/polystyrene/poly(methyl methacrylate)/nanoadditive, cast on a solid substrate, is studied as a numerical experiment. The CuO that is used in antimicrobial coating formulations was chosen as a nanoadditive. The toluene drying from the above mixture is modelled as a coupled heat and mass transfer problem with a moving boundary. The resulting nonlinear model equations are solved by the Galerkin finite element method. This model accounts not only for complex viscoelastic phenomena and glass transition but also for crystallization and nanoadditive effects. The adjustable parameters are kept to a minimum value including a correction coefficient for the mass transfer coefficient at the liquid–gas interface augmented by a crystallization model parameter. These parameters are estimated by fitting data from gravimetric drying experiments. The model predictions show that the toluene weight fraction is below 0.05 at the end of the computational experiment while the respective glass transition temperature profiles vary from 225 K to almost 400 K. The model predictions are in satisfactory agreement with literature data. It is believed that this model could be used in addition to black box models to build efficient hybrid models for drying of similar systems. © 2025 Society of Chemical Industry.

While additive-type flame retardants (FRs) offer ease of application, they may exhibit incompatibility with polyurethane (PU) foams at elevated concentrations, potentially compromising mechanical and morphological properties. This study examines the stabilizing influence of sepiolite (S) on expanded perlite (EP)-doped semi-rigid PU foams (SrPUFs). The thermal stability, morphological structure and flame resistance of S_SrPUF, S_EP_SrPUF and EP_SrPUF samples were evaluated using TGA, SEM and the UL 94 vertical combustion test, respectively. The TGA results indicated a 3.27-fold increase in char residue in the S_EP_SrPUF sample containing sepiolite compared to SrPUF. Additionally, this sample demonstrated a uniform structure akin to pure foam and halted tar flow, extending the combustion time from 50 to 96 s. The S_EP_SrPUF sample, incorporating 2% sepiolite and 8% EP additives, exhibited enhanced strength and flexibility, with mechanical performance improving by 38.4%. The findings suggest that the incorporation of sepiolite with additive-type FRs enhances FR efficacy by establishing a structural equilibrium between the foam matrix and the additive. This study provides significant contributions to both academic and industrial domains. © 2025 Society of Chemical Industry.

In this study, liquid tin(II) n-butoxide (Sn(OnBu)₂) is employed as an initiator in the bulk ring-opening polymerization of l-lactide. Its effectiveness is compared with the conventional tin(II) octoate/n-butanol (Sn(Oct)₂/n-BuOH) initiating system by analyzing kinetics parameters derived from monomer conversion data obtained through gravimetry, ¹H NMR spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Gravimetry kinetics studies of l-lactide ring-opening polymerization in bulk at 120 °C for 24 h reveal that both Sn(OnBu)₂ and Sn(Oct)₂/n-BuOH achieve high conversions (>90%), with first-order rate constants of 0.0432 and 0.0157 min⁻¹, respectively. These results indicate that the highly soluble liquid Sn(OnBu)₂ leads to a faster polymerization rate and higher molecular weight (M_n = 1.45 × 10⁴ g mol⁻¹) than Sn(Oct)₂/n-BuOH (M_n = 6.03 × 10³ g mol⁻¹). However, kinetics studies using ¹H NMR and FTIR suggest that liquid Sn(OnBu)₂ and Sn(Oct)₂/n-BuOH exhibit similar effectiveness in terms of monomer conversion. Finally, the high efficiency of liquid Sn(OnBu)₂ is demonstrated in the first-time synthesis of medical-grade poly(l-lactide) at a large scale (500 g). This advancement paves the way for biomedical applications, such as absorbable surgical sutures, demonstrating performance comparable to commercial medical-grade poly(l-lactide) products. © 2025 Society of Chemical Industry.

The materials commonly used to produce polyurethane foam (PUF) are based on petrochemical derivatives, which can pose long-term environmental and human health risks. Therefore, the search for alternatives to replace these petrochemical derivatives has grown substantially in the last 20 years, aiming mainly at improving polymer properties and leading to a reduced environmental impact. Thus, this review focuses on the advances presented in the literature on PUF production strategies from alternative sources and their impact on polymer material properties, discussing the environmental and technical advantages of using bio-polyols in polyurethane synthesis. From an analysis of the metrics available in the Web of Science and Scopus databases, it was observed that in the last 17 years, 1012 articles and 979 patents were published on bio-based PUFs, mainly in materials sciences, polymeric materials and chemistry. Among these alternative sources used to obtain polyols, castor and soybean vegetable oils are the matrices that stand out the most in current studies. It is concluded that replacing petrochemical polyols with biological sources in the production of PUF allows industrial practices to be aligned with sustainability principles, representing a significant step towards developing cleaner and more efficient technologies. © 2025 Society of Chemical Industry.

Renewable biomass resources, including castor oil and cellulose, present promising avenues for sustainable polymer synthesis. This study involved the fabrication of a novel waterborne polyurethane utilizing cellulose nanofibers (CNFs) as a Pickering emulsion stabilizer and castor oil as a bio-derived polyol. Two different CNFs assessed the function of CNFs in stabilizing castor-oil-derived waterborne polyurethane emulsions by the ratio, their concentration and the emulsion storage duration. Dynamic light scattering and rheological assessments established that CNFs significantly enhanced emulsion stability by forming a semi-flexible network, which impeded droplet coalescence. Moreover, the incorporation of CNFs improved the mechanical performance of castor-oil-derived waterborne polyurethane films. Specifically, the addition of 1 wt% of the longer CNF resulted in an increase in the tensile strength and Young's modulus to 21.2 MPa and 91.0 MPa, respectively, signifying improvements of 103.0% and 256.6% over the CNF-free control. This investigation underscores the synergistic potential of biomass-derived nanomaterials in the design of high-performance, environmentally friendly polymers. © 2025 Society of Chemical Industry.