Chinese Journal of Polymer Science最新文献

Recycling of waste rubber (WR) is crucial for the sustainable development of the rubber industry. The enhancement of interfacial interactions is the main strategy for waste polymer recycling. However, there is a lack of methods for enhancing the interfacial interactions for WR recycling because WR contains abundant inert C—H bonds. Herein, we designed thioctic acid inverse vulcanization copolymers to endow recycled WR with dynamic disulfide interfacial interactions, significantly improving the mechanical properties of recycled WR. These disulfide interfacial interactions among the recycled WR tend to exchange, which dramatically increases the fractocohesive length and prevents stress concentration near the crack tips. When recycled WR is subjected to external stress, the loads are redistributed across a broad region of adjacent regions instead of being concentrated on a limited length scale, which resists crack propagation. This work effectively recycled WR, providing a strategy for solvent-free reaction-derived inverse vulcanization copolymers to improve the toughness of WR recycling.

Membrane distillation (MD) is an advanced membrane separation process that employs hydrophobic microporous membranes to separate non-volatile solutes from the feed solution, driven by vapor pressure gradients generated through thermal difference. This technology offers strong desalination capabilities and efficiently harnesses low-grade thermal energy sources, including geothermal and waste heat, making it a cost-effective solution for freshwater scarcity. Nevertheless, hydrophobic membranes are prone to contamination by surfactants, inorganic salts, and other substances in feed solutions. To address this, low-surface-energy composite nano-inorganic materials composed of carbon nanotubes and silica were modified and synthesized via organosilicon chemistry. A superhydrophobic surface exhibiting a water contact angle of 157.96° was successfully fabricated using above nano-materials on poly(vinylidene fluoride) (PVDF) membrane surface with micro-nano structures via a one-step spray-coating method. Compared to unmodified PVDF membrane, the superhydrophobic membrane demonstrated superior resistance to common scaling agents such as CaCl₂, Mg(OH)₂, CaCO₃, and CaSO₄, while maintaining stable permeate flux (13.4 kg·m⁻²·h⁻¹) during MD tests. Additionally, the modified membrane exhibited enhanced wetting resistance when treating feed solutions containing sodium dodecyl sulfate (SDS), significantly extending the operational lifespan of the membrane. Due to its outstanding performance, this superhydrophobic membrane is expected to promote the practical application of MD technology in the treatment of complex wastewater and efficient seawater desalination.

Given that platinum-based drugs are widely used clinically as chemotherapeutic agents, their severe toxic side effects have attracted significant attention. Consequently, the development of novel nanoprodrugs based on low-toxicity tetravalent platinum (Pt(IV)) complexes holds substantial research value. Herein, we discovered that coumarin derivatives exhibit inherent antitumor efficacy and significantly enhance superoxide anion radicals (•O₂⁻) generation in aqueous solutions under ultrasound (US) irradiation. Given that •O₂⁻ is known to mediate the reduction of Pt(IV) to divalent platinum (Pt(II)), we engineered an US-responsive dual-drug nanoprodrug (P-cisPt(IV)@5-MOP). This nanoprodrug was prepared by covalently conjugating Pt(IV) and methoxy polyethylene glycol hydroxyl (mPEG-OH) to a poly(_l-glutamic acid) (PLG) carrier, followed by encapsulating coumarin derivatives. Under low-intensity US irradiation (1.5 W/cm², 1 MHz, 10 min), P-cisPt(IV)@5-MOP achieved a Pt(IV) reduction rate of 91.4%. Furthermore, upon US exposure, its half-maximal inhibitory concentration (IC₅₀) against 4T1 breast cancer cells decreased dramatically from 25.7 µmol/L to 0.1 µmol/L. Remarkably, this system combined with US therapy yielded a tumor inhibition rate of 90.9%, with 40% of tumor-bearing mice achieving complete eradication of tumors, while exhibiting low systemic toxicity. Collectively, this work not only identifies a novel sonosensitizer capable of generating •O₂⁻ but also develops a new class of ultrasound-activatable Pt(IV) nanoprodrug.

Liver is a vital organ in the human body and plays a central role in the metabolism and detoxification of endotoxins and exotoxins. Bilirubin is an endotoxin derived from hemoglobin (Hb). Removing excess bilirubin in the blood is crucial for the treatment of liver diseases. Hemoperfusion, which relies on adsorbents to efficiently adsorb toxins, is a widely applied procedure for the removal of blood toxins. To broaden and improve the range and performance of hemoperfusion adsorbents, we synthesized cationic hyper crosslinked polymers (HCPs) with strong affinity for bilirubin. This material exhibited outstanding adsorption performance, with a maximum adsorption capacity of 934 mg/g and a removal efficiency of 96%. Further investigation confirmed their excellent selectivity, reusability, and biocompatibility. These findings expand the potential applications of HCPs and provide insight into strategies for constructing promising hemoperfusion adsorbent materials.

Airless tires are essential for enhancing the safety, reliability, and convenience of maintenance of electric bicycles. Polyurethane (PU) is considered a promising candidate for such applications owing to its versatile properties. However, their use is limited by insufficient heat resistance and excessive dynamic heat generation under cyclic loading. In this study, star-shaped trifunctional polypropylene glycerol (PPG3) was incorporated into conventional poly(tetramethylene glycol) (PTMG) and 4,4′-methylenediphenyl diisocyanate (MDI)-based systems to construct microporous star-shaped casting polyurethanes (SCPU), with water serving as a green foaming agent. Unlike conventional small-molecule trifunctional crosslinkers that create junctions within hard segment domains, PPG3 introduces long flexible arms between the hard segments, anchoring the crosslinking points at its molecular core. The large steric hindrance of PPG3 effectively suppresses soft segment crystallization and lowers the degree of microphase separation, whereas the crosslinked network restricts chain mobility, thereby reducing dynamic heat generation. These structural features also enhance the heat resistance, yielding a softening temperature of 183 °C, which is 30.9% higher than that of polyurethane without PPG3. When applied to airless tires by casting SCPU into rubber treads, the fabricated hybrid airless tires achieved a rolling distance of over 3000 km under a load of 65 kg at 25 km/h without structural failure, satisfying practical performance requirements. This strategy offers a simple, solvent-free, and environmentally friendly process, underscoring the potential of SCPU for scalable production of high-performance airless tires.

Conducting hydrogels have garnered significant interest in the field of wearable electronics. However, simultaneously achieving high transparency, high conductivity, strong adhesion, and self-healing ability within a short time remains a major challenge. In this study, a multifunctional mussel-inspired hydrogel was synthesized in only 5 min, with polydopamine (PDA)-polypyrrole (Ppy)-polyaniline (PANi) and poly(vinyl alcohol) (PVA) nanoparticles incorporated into the polyacrylamide (PAM) network. The resulting hydrogel exhibited high transparency (about 90% light transmission in the range of 400–800 nm), high conductivity ((95.4±0.4)×10⁻⁴ S/cm), tensile strength (32.60±1.03 kPa), strain at break (904.46%±11.50%), and adhesive strength (30–60 kPa). It also demonstrated rapid self-healing properties (about 48% strength recovery within 1 h at 50 °C) and water-dependent shape memory behavior. As a wearable strain sensor, the hydrogel successfully detected finger flexion, wrist movements, facial expression changes, and breathing with high sensitivity and stability. The calculated gauge factor (GF) was 7.44±0.31, which is higher than that of many previously reported hydrogels. Compared with previous oyster-inspired or Ppy-based hydrogels, our system showed a much shorter synthesis time, higher transparency, and enhanced multifunctionality. These findings highlight the potential of the proposed hydrogel for next-generation flexible electronics, e-skin, and biomedical monitoring devices.

Nucleation, which is the initial step of crystallization, critically governs the polymer crystallization behavior, influencing the crystallization temperature, kinetics, and morphology. However, the direct observation of the nucleation process in polymers remains elusive owing to spatial and temporal resolution limitations. This feature article summarizes the recent progress in understanding polymer nucleation within confined and interface-dominated environments, focusing on three representative systems: anodic aluminum oxide templates and nanocomposites containing nanoparticles or nanosheets. The interplay between finite size and interfacial effects has revealed some novel phenomena, such as homogeneous nucleation, surface nucleation, prefreezing, and supernucleation.

Polyurethane elastomers exhibit high dielectric constants owing to their polar groups, and can be used as energy storage capacitors. Energy storage depends not only on the dielectric constant but also on the dielectric loss. However, the relationship between chain structure and dielectric properties is not yet clear. Ketal-containing crosslinked polyurethane elastomers were prepared using cyclic ketal diol as a chain extender. The effect of the soft segment length on the dielectric properties and energy storage was investigated. The cause of the change in the dipolar polarization with the soft segment length was analyzed. As the soft segment length increased, the hard-soft hydrogen bonding decreased, whereas the hard-hard hydrogen bonding increased. Under the action of an electric field, the polar bonds in the ketal-containing polyurethane elastomer overcome the hydrogen bonding between hard-soft segments to produce polarization; meanwhile, they also experience crankshaft motions to generate polarization. The former has a relatively high relaxation activation energy of approximately 10–20 kJ·mol⁻¹, resulting in a large dielectric loss. The latter has a relatively low relaxation activation energy, approximately 0.7–1.7 kJ·mol⁻¹, leading to low dielectric loss. As a result, the dielectric constant showed a decreasing trend, and the dielectric loss gradually decreased. This study provides a theoretical foundation for improving the dielectric properties of polyurethane elastomers.

Bio-based 2,5-furandicarboxylic acid polyesters offer significant promise for reducing energy and environmental crises. However, their intrinsic flammability remains a critical limitation, and conventional flame-retardant strategies often compromise their mechanical properties, hindering their practical applications. Herein, a 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-based comonomer (DDP) was used to synthesize flame-retardant poly(ethylene furandicarboxylate-co-phosphaphenanthrene) (PEFDn). The covalent integration of DDP confers intrinsic flame retardancy, avoiding the plasticization and migration issues associated with additive-type systems. Upon thermal decomposition, the DOPO-derived moieties release phosphoric acid and radical scavengers, promoting char formation and suppressing flame propagation. Furthermore, density functional theory (DFT) calculations combined with non-covalent interaction (NCI) analysis revealed that DOPO dimer molecules adopt a stable parallel-displaced π–π stacking configuration, potentially facilitating microphase separation and enhancing the energy dissipation capability. PEFD₁₀ achieves a UL-94 V-0 rating while simultaneously increasing impact toughness from 1.5 kJ/m² to 14.7 kJ/m². Importantly, PEFDn maintained acceptable oxygen-barrier properties. PEFD₁₀ also exhibited high transparency and UV-shielding performance. The combination of intrinsic flame safety, impact-toughness resistance, UV shielding, and an oxygen barrier ensures reliable protection of electrical components and long-term operational stability. The integration of multiple critical properties within a single bio-based material represents a novel approach for enabling sustainable polymer solutions for high-performance electrical applications.

Poly(phenylene oxide) (PPO) exhibits excellent dielectric properties, making it an ideal substrate for high-frequency, high-speed copper-clad laminates. The phenolic hydroxyl group at the end of PPO plays a key role in its reactivity. Accurately quantifying the phenolic hydroxyl content in PPO is essential but challenging. In this study, we proposed a method for measuring the phenolic hydroxyl content of PPO using differential UV absorption spectroscopy. In alkaline solutions, the phenolic hydroxyl in PPO completely ionizes to form phenoxide ions, leading to a significant increase in UV absorbance at approximately 250 and 300 nm. Notably, the differential UV absorbance at approximately 300 nm was directly proportional to the phenolic hydroxyl concentration. Using 2,6-dimethylphenol as a standard, a calibration curve was established to relate the phenolic hydroxyl concentration to differential UV absorbance at approximately 300 nm, providing a precise and straightforward method for phenolic hydroxyl quantification in PPO with distinct advantages over conventional techniques.