Macromolecular Chemistry and Physics最新文献

In free radical ring-opening copolymerization of cyclic ketene acetals (CKA) with vinyl monomers, a major challenge is the often-low reactivity of CKAs and thus insufficient ester incorporation and homogeneity. Most workarounds, like semibatch copolymerization, require a considerable change in the system. In this work, we report a method to improve ester incorporation into the backbone and homogeneity of the polymer by using a batch copolymerization in 1,4-dioxane above solvent boiling point. The monomer system of 2-methylene-4-phenyl-1,3-dioxolane (MPDL) and syringyl methacrylate (SM) showed improved copolymerization parameters (r_MPDL = 0.032 and r_SM = 2.464) compared to the polymers obtained at 70°C in anisole. Basic hydrolysis with potassium hydroxide (KOH) in tetrahydrofuran (THF)/methanol (MeOH) was conducted to study structural homogeneity and was compared with semibatch experiments.

Electrically conductive polymers are a groundbreaking class of materials commonly utilized in medical research focused on healthcare devices such as biosensors. They share the mechanical properties of a classical polymer as well as the electronic properties of metals. This allows them to function as flexible, lightweight, and highly efficient components in both wearable and implantable sensor technologies. Although research has shown promising findings, most of the polymer sensors presented are only partially or not at all biologically compatible with the human body. This work demonstrates a new electroconductive polymer matrix composed of bio-based materials–bovine gelatin, whey protein isolate (WPI), polyaniline (PANI), and phytic acid (PA)– as a soft, compliant material. The results showed a homogeneous and well-integrated matrix that remains stable up to $��{115}^{\circ }�C�$. The water content in the samples ranged from 29.99% to 63.81%, depending on the method of preparation. The electromechanical properties before and after self-healing were also investigated, along with antibacterial properties against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. This study developed a new formulation of a conductive polymer matrix that is potentially biocompatible, yet still exhibits satisfactory mechanical properties like its predecessors, making it a candidate for bio-sensing applications.

Compared with conventional polyurethanes, non-isocyanate polyurethanes (NIPUs) prepared via the polyaddition of bis(cyclic carbonates) and diamines have attracted considerable attention due to their avoidance of highly toxic precursors such as isocyanates and phosgene. However, the limited availability of bis(cyclic carbonates) has hindered the further industrialization of NIPUs. Therefore, we proposed a strategy for preparing NIPU using commercial biobased isoprene as starting material. As a proof of concept, A three-step synthetic route was developed to convert isoprene into a series of bis(cyclic carbonates) via epoxidation, CO₂ cycloaddition, and thiol–ene click reactions. Subsequently, the designed cyclic carbonate monomers were copolymerized with four different diamine monomers to synthesize NIPUs. The molecular weight (M_n = 6.0∼24.0 kDa) and thermal properties (T_g = 1.4∼34.8°C) of the resulting NIPU could be tailored through regulating the structure of monomers. Additionally, the produced NIPU was applied as adhesive showed an adhesion strength up to 1.87 MPa on stainless steel substrates. The proposed strategy not only broadens the monomer sources of NIPUs but also effectively increases their biocarbon content.

Conductive hydrogels demonstrate broad prospects in the field of wearable strain sensors due to their good flexibility, electrical conductivity, and biocompatibility. However, the complexity of practical application environments imposes higher requirements on the comprehensive properties of such materials, including electrical conductivity, mechanical strength, self-healing, and adhesion. To address this, this study introduces the conductive polymer polyaniline (PANI) into a sodium polyacrylate (PAAS) hydrogel matrix, successfully constructing a PAAS/PANI conductive hydrogel with a dual chemically cross-linked network via a one-pot method. Experimental results indicate that the incorporation of PANI not only effectively enhances the electrical conductivity of the hydrogel but also improves its mechanical properties. When the PANI content reaches 7.5 wt%, the hydrogel exhibits good overall performance: its tensile strength reaches 314 kPa, the elongation at break reaches 872%, and the electrical conductivity reaches 2.46 S m⁻¹. In terms of sensing performance, the material also demonstrates outstanding characteristics: under 600% tensile strain, its gauge factor (GF) reaches 4.52, along with negligible hysteresis and rapid response and recovery speeds. Additionally, the PAAS/PANI hydrogel possesses good thermal stability, self-healing properties, adhesion, and biocompatibility. Based on this hydrogel, the constructed wearable strain sensor can accurately, stably, and real-time monitor various human joint movements.

This study reports a novel adsorbent prepared via a Pickering emulsion-template method for the efficient adsorption of Ce(III) from aqueous solutions. Water-in-oil Pickering emulsions were first stabilized by commercial nano-SiO2, using an aqueous sodium alginate solution as the dispersed phase and kerosene-diluted di-(2-ethylhexyl) phosphate (P204) as the continuous phase. The emulsion droplets were then gelled in a Ca²⁺ solution to form stable Pickering emulsion hydrogel beads (PEHG), thereby encapsulating the P204-containing organic phase within a calcium alginate matrix. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed the successful encapsulation and the structural integrity of the PEHG. Batch adsorption experiments demonstrated that the adsorption kinetics followed a pseudo-second-order model, indicative of chemisorption, while the equilibrium data were best described by the Redlich-Peterson isotherm, suggesting a complex adsorption mechanism involving both monolayer and multilayer interactions. Remarkably, the PEHG retained a Ce(III) removal efficiency above 99% over five consecutive adsorption-desorption cycles, with no observable structural degradation or leakage of the encapsulated phase. This strategy of encapsulating the functional organic phase (P204) within a hydrogel matrix not only enhances its utilization efficiency but also effectively prevents its leakage into the aqueous environment, offering a promising and sustainable approach for rare earth element recovery.

Plastic pollution is a significant environmental issue, and poly(L-lactide) (PLLA) is one of the most common biodegradable polymers that meets current environmental protection needs. However, enhancing its degradation rate in soil remains a continuing challenge. Herein, we mainly investigate the phase morphology evolution, mass loss, molecular weight loss, mechanical properties, thermodynamic properties, and molecular structure changes during the soil burial degradation of PLLA/poly(ether-block-amide) (PEBA) blends. After 90 days of soil burial degradation, the mass loss of PLLA/PEBA (80/20) blend and pure PLLA is 17.3% and 2.3%, the weight-average molecular weight loss is 24.7% and 15.8%, and the tensile strength decreases by 75.6% and 32.2%, respectively, suggesting a faster soil burial degradation rate of the blend. The enhanced degradation rate is attributed to the existence of phase interfaces, which is beneficial to the water absorption and the attack of microorganisms. Soil burial degradation primarily occurs in the amorphous regions of PLLA, leading to an increase in the relative content of crystalline regions. The molecular structure changes reveal that the mechanism of soil burial degradation of PLLA mainly involves random chain scission of the ester groups on the backbones.

Thyroid cancer is one of the fastest-growing endocrine malignancies, and advanced disease remains difficult to manage because of metastasis, recurrence, and resistance to radioactive iodine. To help address limitations in current therapy and curcumin (Cur) delivery, we designed a multifunctional electrochemical nanoplatform that combines Cur loading with signal readout in a single system. Compound 1 was first used to modify hyaluronic acid (HA), followed by conjugation with the organosilane TESPSA to obtain the hybrid material 1-HA-TESPSA, which was then assembled with the porous coordination polymer CP1 and loaded with Cur, yielding 1-HA-TESPSA@CP1@Cur. Structural and electrochemical characterizations (XRD, Raman, CV, EIS) confirmed the preservation of an ordered framework, improved charge-transfer properties, and suitable performance for Cur sensing. In vitro studies using human thyroid cancer TPC-1 cells showed that 1-HA-TESPSA@CP1@Cur inhibited cell proliferation more effectively than free Cur, while the blank carrier exhibited minimal cytotoxicity. Preliminary mechanistic investigations indicated that the nanoformulation upregulated the tumor suppressor PTEN, which may contribute to its antiproliferative effects. Overall, this work provides a proof-of-concept Cur nanocarrier with integrated electrochemical detection and delivery functions, suggesting potential for more precise management of thyroid cancer pending further in-depth validation.