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3-nitro-1,2,4-triazol-5-one (NTO) has been widely used as a kind of insensitive single-compound explosive owing to its excellent balance between safety and explosive energy. To reduce its possible acid corrosion and extend its application to insensitive ammunition, acid protection research on NTO-based explosives is significant. Traditionally, the acid protection effect was evaluated by metal corrosion, which is time-consuming and qualitative. An efficient and quantitative method is desirable for evaluating the acid protection effect and exploring novel protection materials. Herein, a polyimide of 4,4’-(hexafluoroisopropene)diphthalic anhydride (6FDA)/2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl (TFMB) was synthesized by replacing the 4,4’-diaminodiphenyl ether (ODA) monomer with a TFMB monomer to act as an acid-protective coating material for NTO-based explosives. Compared with three other coating materials, polyvinylidene fluoride (PVDF), polyetherimide (PEI), and copolyimide (P84), the fluorinated polyimide exhibits the best acid protection effect. Moreover, a new method was constructed to obtain the pH time-dependent curve in order to evaluate efficiently the acid protection effect of the polymer materials. By the virtue of molecular dynamic simulation (Materials Studio 2023), the interfacial effects of the coating materials with NTO-based explosives were obtained. The study provides an interpretation of the acid protection effect on the molecular level, suggesting that the higher content of fluorine atoms is beneficial for stabilizing the active hydrogen atom of the NTO by forming intermolecular hydrogen bonds.

In an effort to effectively control coal dust pollution and thereby reduce the harm of coal dust to human health, we prepared a highly efficient composite dust suppressant. First, dynamic contact angle and zeta potential measurements were used to select sodium dodecyl sulfonate (SDS) over sodium carboxymethyl cellulose and trisodium methyl silicon as the complementary additive to soy protein isolate for the dust suppressant. We employed viscosity and wind erosion resistance tests to compare the performance of the composite dust suppressant with three common, commercially available suppressants. As the concentration of the composite dust suppressant was increased, the viscosity increased, reaching a maximum value of 22.7 mPa·s at a concentration of 5 wt%. The 5 wt% concentration of the composite dust suppressant provided the lowest wind erosion rate (20.62%) at a wind speed of 12 m/s. The composite dust suppressant also had good bonding performance and wind erosion resistance. Scanning electron microscopy, X-ray diffraction, and thermogravimetric analysis were used to characterize the properties of the dust suppressants. The dust suppressant, which had a crystal-like structure, could easily capture coal dust and form an effective package. In addition, the density of the dust suppressant film increased as its crystallinity increased. The increased density was beneficial in that it enabled the dust suppressant to form a hard, solidified shell on the surface of coal dust, which improved dust suppression. The composite dust suppressant also had good thermal stability.

Oil/water separation processes have garnered significant global attention due to the quick growth in industrial development, recurring chemical leakages, and oil spills. Hence, there is a significant demand for the development of inexpensive superwetting materials in an eco-friendly manner to separate oil/water mixtures and emulsions. In this study, a superwetting melamine sponge (SMS) with switchable wettabilities was prepared by modifying melamine sponge (MS) with sodium dodecanoate. The as-prepared SMS exhibited superhydrophobicity, superoleophilicity, underwater superoleophobicity, and underoil superhydrophobicity. The SMS can be utilized in treating both light and heavy oil/water mixtures through the prewetting process. It demonstrated fast permeation fluxes (reaching 108,600 L m−2 h−1 for a light oil/water mixture and 147,700 L m−2 h−1 for a heavy oil/water mixture) and exhibited good separation efficiency (exceeding 99.56%). The compressed SMS was employed in separating surfactant-stabilized water-in-oil emulsions (SWOEs), as well as surfactant-stabilized oil-in-water emulsions (SOWEs), giving high permeation fluxes (reaching 7210 and 5054 L m−2 h−1, respectively). The oil purity for SWOEs’ filtrates surpassed 99.98 wt% and the separation efficiencies of SOWEs exceeded 98.84%. Owing to their remarkable capability for separating oil/water mixtures and emulsions, eco-friendly fabrication method, and feasibility for large-scale production, our SMS has a promising potential for practical applications.

A hole array was fabricated via photolithography to wet the bottoms of holes using oxygen plasma. Amide-terminated silane, a water immiscible compound before hydrolysis, was evaporated for deposition on the plasma-treated hole template surface. The silane compound was hydrolyzed along the edges of circular sides of the hole bottom to form a ring of an initiator after halogenation. Poly(methacrylic acid) (PMAA) was grafted from the ring of the initiator to attract Ag clusters (AgCs) as AgC–PMAA hybrid ring (SPHR) arrays via alternate phase transition cycles. The SPHR arrays were modified with a Yersinia pestis antibody (abY) to detect the antigen of Yersinia pestis (agY) for plague diagnosis. The binding of the agY onto the abY-anchored SPHR array resulted in a geometrical change from a ring to a two-humped structure. The reflectance spectra could be used to analyze the AgC attachment and the agY binding onto the abY-anchored SPHR array. The linear range between the wavelength shift and agY concentration from 30 to 270 pg mL−1 was established to obtain the detection limit of ~12.3 pg mL−1. Our proposed method provides a novel pathway to efficiently fabricate a ring array with a scale of less than 100 nm, which demonstrates excellent performance in preclinical trials.

To afford an intact double network (sample abbr.: DN) hydrogel, two-step crosslinking reactions of poly(2-acrylamido-2-methylpropanesulfonic acid) (i.e., PAMPS first network) and then poly(acrylic acid) (i.e., PAA second network) were conducted both in the presence of crosslinker (N,N′-methylenebisacrylamide (MBAA)). Similar to the two-step processes, different contents of 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) oxidized cellulose nanofibers (TOCN: 1, 2, and 3 wt.%) were initially dispersed in the first network solutions and then crosslinked. The TOCN-containing PAMPS first networks subsequently soaked in AA and crosslinker and conducted the second network crosslinking reactions (TOCN was then abbreviated as T for DN samples). As the third step, various (T–)DN hydrogels were then treated with different concentrations of FeCl3(aq) solutions (5, 50, 100, and 200 mM). Through incorporations of ferric ions into (T–)DN hydrogels, notably, three purposes are targeted: (i) strengthen the (T–)DN hydrogels through ionic bonding, (ii) significantly render ionic conductivity of hydrogels, and (iii) serve as a catalyst for the forth step to proceed with in situ chemical oxidative polymerizations of pyrroles to afford polypyrrole-containing (sample abbr.: Py) hydrogels [i.e., (T–)Py–DN samples]. The characteristic functional groups of PAMPS, PAA, and Py were confirmed by FT–IR. Uniform microstructures were observed by cryo scanning electron microscopy (cryo-SEM). These results indicated that homogeneous composites of T–Py–DN hydrogels were obtained through the four-step process. All dry samples showed similar thermal degradation behaviors from the thermogravimetric analysis (TGA). The T2–Py5–DN sample (i.e., containing 2 wt.% TOCN with 5 mM FeCl3(aq) treatment) showed the best tensile strength and strain at breaking properties (i.e., σTb = 450 kPa and εTb = 106%). With the same compositions, a high conductivity of 3.34 × 10−3 S/cm was acquired. The tough T2–Py5–DN hydrogel displayed good conductive reversibility during several “stretching-and-releasing” cycles of 50–100–0%, demonstrating a promising candidate for bioelectronic or biomaterial applications.

Polystyrene nanospheres (PNs) were embedded in bovine skin gelatin gels with a poly(N-isopropylacrylamide) (PNIPAAm) network, which were denoted as NGHHs, to generate thermoresponsive behavior. When 265 nm PNs were exploited to generate the pores, bovine skin gelatin extended to completely occupy the pores left by PNs below the lower critical solution temperature (LCST), forming a pore-less structure. Contrarily, above the LCST, the collapse of hydrogen bonding between bovine skin gelatin and PNIPAAm occurred, resulting in pores in the NGHH. The behavior of pore closing and opening below and above the LCST, respectively, indicates the excellent drug gating efficiency. Amoxicillin (AMX) was loaded into the NGHHs as smart antibiotic gating due to the pore closing and opening behavior. Accordingly, E. coli. and S. aureus were exploited to test the bacteria inhibition ratio (BIR) of the AMX-loaded NGHHs. BIRs of NGHH without pores were 48% to 46.7% at 25 and 37 °C, respectively, for E. coli during 12 h of incubation time. The BIRs of nanoporous NGHH could be enhanced from 61.5% to 90.4% providing a smart antibiotic gate of bovine skin gelatin gels against inflammation from infection or injury inflammation.

Gypsum molds have been developed as an alternative for the Rapid tooling (RT) method used in injection molding. However, the poor capability of the heat delivery forces the gypsum mold to operate under a high-risk condition, and distortion of the molded part becomes apparent. The goal is to investigate the effect of a heat sink on the reduction of the gypsum mold temperature and to establish a methodology for the heat sink design. The methodology used the advantage of the electrical circuit concept to analyze the mold temperature. The heat transfer of a mold was modeled using an equivalent thermal circuit. After all the components on the circuit were determined, the heat transfer rate could then be calculated. Once the heat transfer rate was known, the mold temperature could be easily analyzed. A modified thermal circuit considering transverse heat conduction was also proposed, which estimated the mold temperature more accurately. The mold temperature was reduced by 16.8 °C when a gypsum mold was installed with a 40 mm thick heat sink in a parallel configuration. Moreover, the reduction of the mold temperature improved the deflection of the molded part from 0.78 mm to 0.54 mm. This work provides a quick approach to analyze the mold temperature based on the thermal circuit concept. As the cooling system of the mold was modularized analytically, important properties of the cooling system in the heat transfer process were revealed by analyzing the thermal circuit of the mold, for example, the heat transfer rate or the mold temperature.

Atom transfer radical polyaddition (ATRPA) was utilized herein to synthesize a specific functional polyester. We conducted ATRPA of 4-vinylbenzyl 2-bromo-2-phenylacetate (VBBPA) inimer and successfully obtained a linear type poly(VBBPA) (PVBBPA) polyester with benzylic bromides along the backbone. To obtain a novel amphiphilic polymer bottlebrush, however, the lateral ATRP chain extension of PVBBPA with N-vinyl pyrrolidone (NVP) met the problem of quantitative dimerization. By replacing the bromides to xanthate moieties efficiently, we thus observed a pseudo linear first order reversible addition−fragmentation chain transfer (RAFT) polymerization to obtain novel poly(4-vinylbenzyl-2-phenylacetate)-g-poly(NVP) (PVBPA-g-PNVP) amphiphilic polymer bottlebrushes. The critical micelle concentration (CMC) and particle size of the amphiphilic polymer bottlebrushes were characterized by fluorescence spectroscopy, dynamic light scattering (DLS), and scanning electron microscopy (SEM) (CMCs < 0.5 mg/mL; particle sizes = ca. 100 nm). Toward drug delivery application, we examined release profiles using a model drug of Nile red at different pH environments (3, 5, and 7). Eventually, low cytotoxicity and well cell uptake of the Madin-Darby Canine Kidney Epithelial (MDCK) for the polymer bottlebrush micelles were demonstrated.

In this work, a unique hybrid system is proposed for one-dimensional gratings comprising of poly(glycidyl methacrylate) (PGMA) brushes and CdS quantum dots (CQDs). Generally, the emission of QDs is too weak to be observed in a dry state. Plasmonic resonances of the grating structures can be used to enhance the light emission or absorption of CQDs. The interaction between PGMA plasmonic nanostructures and inorganic CQDs plays a crucial role in engineering the light harvest, notably for optoelectronic applications. Extinction measurements of the hybrid system consisting of a PGMA grating and CQDs are reported. We designed one-dimensional gratings with various resolutions to tune the absorptance peaks of grating. PGMA grating grafted from a 1.5 µm resolution of trench arrays of photoresist exhibited absorptance peak at 395 nm, close to the absorption peak of CQDs, resulting in the photoluminescence enhancement of CQDs on the grating due to high charge carriers’ recombination rate. Generally, the emission of quantum dots occurs under irradiation at characteristic wavelengths. Immobilizing QDs on the grating facilitates the emission of QDs under irradiation of full-wavelength light. Furthermore, the PGMA gratings with CQDs were immersed in various solvents to change the geometries resulting the shift of absorptance peak of grating. The proposed method could be applied for sensing the nature of the surrounding media and vice versa, as well as for various media of solvents.

The synthesis of novel branched/star copolymers which possess unique physical properties is highly desirable. Herein, a novel strategy was demonstrated to synthesize poly(ε-caprolactone) (PCL) based miktoarm star (μ-star) copolymers by combining ring-opening polymerization (ROP), styrenics-assisted atom transfer radical coupling (SA ATRC), and atom transfer radical polymerization (ATRP). From the analyses of gel permeation chromatography (GPC), proton nuclear magnetic resonance (1H NMR), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), well-defined PCL-μ-PSt (PSt: polystyrene), and PCL-μ-PtBA (PtBA: poly(tert-butyl acrylate) μ-star copolymers were successfully obtained. By using atomic force microscopy (AFM), interestingly, our preliminary examinations of the μ-star copolymers showed a spherical structure with diameters of ca. 250 and 45 nm, respectively. We successfully employed combinations of synthetic techniques including ROP, SA ATRC, and ATRP with high effectiveness to synthesize PCL-based μ-star copolymers.

Enhancing drug loading efficacy and stability of polymeric micelles remains a grand challenge. Here we develop adamantane-based star copolymers adamantane-[poly(ε-caprolactone)-b-poly(2-(diethylamino)ethyl methacrylate)-b-poly(poly(ethylene glycol) methyl ether methacrylate)]4 (Ad-(PCL-b-PDEAEMA-b-PPEGMA)4) and their self-assembled micelles for controlled drug delivery. Results show that the polymers have excellent stability in solution with low critical micelle concentration (CMC) (0.0025–0.0034 mg/mL) and the apparent base dissociation constant (pKb) of the polymers is from 5.31 to 6.05. Dynamic light scattering analysis exhibits the great environmental response capability of the pH-sensitive micelles according to particle sizes and zeta potentials. With the synergy effect of the adamantane and hydrophobic block, the micelles display the high Doxorubicin (DOX) loading efficacy (up to 22.4%). The DOX release study shows that the micelles are capable of controlled release for drug. This work indicates the Ad-(PCL-b-PDEAEMA-b-PPEGMA)4 micelles may provide new guidelines for drug control and release system in overcoming cancer treatment.

Through the reversible addition–fragmentation chain transfer (RAFT) copolymerization of 3-ethyl-1-vinyl-2-pyrrolidone (C2NVP) and N-vinylpyrrolidone (NVP), a series of well-defined P(C2NVP-co-NVP) copolymers were synthesized (Mn = ca. 8000 to 16,000 and Mw/Mn

We grafted thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) brushes from monodisperse SiO2 microspheres through surface-initiated atom transfer radical polymerization (SI ATRP) to generate core-shell structured SiO2@PNIPAM microspheres (SPMs). Regular-sized SPMs dispersed in aqueous solution and packed as photonic crystals (PCs) in dry state. Because of the microscale of the SPMs, the packing behavior of the PCs in water can be observed by optical microscopy. By increasing the temperature above the lower critical solution temperature (LCST) of PNIPAM, the reversible swelling and shrinking of the PNIPAM shell resulted in dispersion and precipitation (three-dimensional aggregation) of the SPM in aqueous solution. The SPMs were microdispersed in a water layer to accommodate the aggregation along two dimensions. In the microdispersion, the SPMs are packed as PCs with microscale spacing between SPMs below the LCST. When the temperature is increased above the LCST, the microdispersed PCs exhibited a close-packed arrangement along two dimensions with decreased spacing between SPMs. The change in spacing with increasing temperature above the LCST resulted in a color change from red to blue, which could be observed by the naked eye at an incident angle. Thus, the SPM array could be applied as a visual temperature sensor.