Reactive & Functional Polymers最新文献

This paper describes the development of a method of catalytic polymerization that was then applied to synthesize sulfate-based oligomers from sulfamide. Two molecules, copper triflate and copper acetate, catalyzed the formation of oligomers with diol monomers. Two oligomers were identified as products of the reactions. Oligomers with sulfate incorporated in the backbone proved to have an ability for ion diffusion. When the oligomers were doped with lithium salt, anion transportation was predominant, as shown by solid-state NMR. The lithium ion was found to be strongly bonded to the backbone, while the anion was highly mobile. To corroborate this finding, we conducted molecular dynamics (MD) simulations, which revealed the structural characteristics and static properties of two electrolytes containing LiTFSI and two different polyethylene oxide oligomers. Interactions between the anion and cation were analyzed through computation of the radial distribution function (RDF) and the spatial distribution function (SDF). Our findings indicate that while the anion presents weak interactions with the polymer chain, the cation interacts strongly with the oligomer backbone.

Modified P(NIPAm-co-AAc) copolymers are prepared using Radical Addition Fragmentation Chain Transfer (RAFT) copolymerization by varying the concentration of castor oil sourced acrylated epoxy methyl ricinoleate (AEMR). Subsequently, hydrogels are prepared by integrating copolymers with polyvinyl alcohol (PVA) via freeze-thaw process. The employment of RAFT polymerization yielded copolymers with dispersity (D) value of 1.2–1.3 revealing the formation of structurally well controlled polymer chains. The lower critical solution temperature (LCST) of the copolymers (∼30–35 °C) are tuned to the range of physiological temperature (∼37 °C) in PVA hydrogel system. Temperature dependent viscoelastic properties indicated that the characteristics of copolymeric solutions and hydrogels are composition dependent while undergoing noncovalent interactions and the conformational changes and the samples showed extremely elastic behaviour beyond LCST. Swelling ratio of hydrogels are also found to be pH dependent, which displayed higher swelling ratio in alkaline and reduced swelling ratio in acidic medium. Cytotoxicity studies with L929 cells showed that the copolymers and hydrogels exhibited desirable biocompatibility, which gets improved with AEMR concentrations. Thus, these dual responsive PA-AEMR-PVA smart hydrogels can be used as a viable functional material for possible bio-medical applications.

In this study, we synthesized benzophenone-based main chain polybenzoxazine (BP-PBz) as a type II macroinitiator and this initiator was used to synthesize acrylate-based polybenzoxazine copolymers. BP-PBz effectively initiated the polymerization of methyl methacrylate (MMA) and poly(ethylene glycol) diacrylate (PEGDA), resulting in either polybenzoxazine-grafted-poly(MMA) or crosslinked polybenzoxazine networks. Polymerizations of the formulations were performed upon photolysis at ca. 300 nm. The obtained polymers retained their oxazine functionality and subsequent thermal curing was applied successfully at relatively lower temperatures than conventional benzoxazines. The precursors are shown to have a dual curable character that could be beneficial for deep curing purposes. The synthesized polymers were characterized using various techniques, including nuclear magnetic resonance (NMR), Fourier-transform infrared (FT-IR), ultraviolet-visible (UV–Vis) spectroscopy, and thermogravimetric analysis (TGA), along with differential scanning calorimetry (DSC).

Polycaprolactone (PCL) based thermadapt shape memory polymers (SMPs) have exhibited superiority over traditional analogues by allowing shape-editing to reconfigure permanent shapes into more complex geometrical shapes, driven by the pursuit of advanced functionalities for high-value applications. Nevertheless, although transesterification-based PCL networks exhibit impressive shape reconfigurability as prototypical thermadapt SMPs, there are still constraints in terms of the need for significant flexibility in architectural adjustment and property modulation without compromising reconfigurability, which would be relevant for practical applications. Here, we present a simple yet efficient strategy to create PCL-based thermadapt SMPs that possess a highly tunable structure and properties, as well as exceptional reconfigurability. The family of SMPs, called thermadapt shape memory AB copolymer networks (AB-CPNs), was synthesized by UV-initiated free radical polymerization between PCL diacrylate as crosslinker and 4-hydroxybutyl acrylate (HBA) as comonomer. The thermadapt AB-CPNs allow for significant structural alterations with 0 wt% to 70 wt% HBA while maintaining excellent shape memory and shape reconfigurability effects. The insertion of the polymer segment containing free hydroxyls not only promises tunable material properties but also makes network rearrangement easier since dynamic hydroxy-ester bonds are more active than dynamic ester-ester bonds. It is envisioned that the thermadapt shape memory AB-CPNs with widely tunable macroscopic properties will drive progress in the real-world applications of SMP devices with complicated geometric structures.

Superhydrophobic surfaces exhibit significant potential for applications in biotechnology, biomedicine, and materials science, owing to their multifunctional properties such as self-cleaning and low solid-liquid adhesion. Diverging from traditional superhydrophobic surfaces, the more durable omniphobic NP-GLIDE (Nanometer-sized Pools of a Grafted Lubricating Ingredient for Dewetting Enablement) coating introduces a surface composed of a covalently bonded monolayer. This monolayer, a liquid-like polymer, integrates nanoscale pools of grafted liquid components within its matrix to enable dewetting. This paper offers a concise review of the latest developments in NP-GLIDE coating, encompassing its synthesis methods using various resins, structural characteristics, and its applications in omniphobic technologies. The assessment of these coatings considers their hydrophobic and oleophobic properties on diverse surfaces, their durability, and any additional functional capabilities. It also deliberates on the future of the field, highlighting the imperative to strike a balance between design simplicity, scalability, and environmental impact to facilitate the advent of technologies ready for mass production.

We proposed a feasible and straightforward approach for fabricating a superhydrophobic polytetrafluoroethylene coated polyphenylene sulfide/aramid composite film (PTFE@PPS/ACFs porous membrane) for oil-water separation. This process involves utilizing a wet paper making process combined with a spray coating technique. The PPS/ACFs composite membrane displays a three-dimensional network structure by the application of wet papermaking approach. The uniformly spray coating of PTFE on its surface results in a superhydrophobic PTFE@PPS/ACFs porous membrane (PPAM). The membrane obtained through this method can effectively separate oil and water. It is remarkable in separating oil-water lotion stabilized by surfactant, achieving a separation efficiency of up to 99.9 % with a high flux of 8000 L/m²·h⁻¹. Additionally, owing to the inherent thermal stability of the membrane, the PPAM is recyclable. In summary, the PTFE@PPS/ACFs porous membrane is a promising for separating various oil-water emulsions. Its outstanding performance, including high separation efficiency, flux, and recyclability, underscores its potential for practical applications for oil-water separation.

Developing the packaging materials with superior high-temperature stability to meet the requirement of high-power devices is crucial. Herein, we synthesized 4-(4-aminophenoxy)phthalonitrile (APN) and blended it with polyfunctional epoxy resin (EP) to obtain the APN/EP (APNE) binary blends. Further, we employed the APNE as resin matrix to prepare a new high-temperature stable molding compound, aminophenoxyphthalonitrile epoxy molding compound (AEMC), aiming for high-power device packaging. Firstly, the curing behavior, reaction mechanism, thermal stability, and mechanical properties of the APNE system were systematically studied. Although the crosslinking density of the cured APNE decreased with increasing the APN content, the introduction of APN made the cured resins have the stable and rigid structures of isoindoline, triazine, and phthalocyanine. Thus, the cured APNE had the initial thermal decomposition temperature above 370 °C, the glass transition temperature (T_g) up to 306 °C, and the char yield at 800 °C up to 61.1 %, showing an excellent thermal performance. In addition, the flexural strength, flexural modulus, and impact strength of the cured APNE also increased with increasing the APN content. Such good properties of the APNE resin matrix endowed the AEMC with an attractive performance. The AEMC exhibited a good compatibility in molding process with the current epoxy molding compound (EMC). The T_g, thermal-aging resistance, intrinsic flame retardancy, dielectric properties, and thermal conductivity of the cured AEMC were all superior to those of the cured EMC. Therefore, the AEMC shows a good application prospect in the field of high-temperature electronic packaging.

Fire hazards associated with UV-curable polymers have limited their broader application. This study aims to develop efficient and environmentally friendly safety strategies for UV-curable polymers. Microcapsules were synthesized via simple coacervation, using perfluoro(2-methyl-3-pentanone) (PFMP) as the core and gelatin (GE) as the wall material. PFMP@GE microcapsules were then incorporated into UV-curable resin prepolymer to produce a UV-curable resin board with active fire-extinguishing capabilities. The microcapsules' morphology, chemical composition, and thermal stability of the microcapsules were analyzed, along with the safety performance of the UV-curable resin board containing PFMP@GE microcapsules in confined spaces with sustained combustion. The morphology, chemical composition, and thermal stability results indicate that the microcapsules, synthesized under emulsification conditions (5 min of shearing at 8000 rpm and a 2.0 % w/v ratio of sodium dodecyl benzene sulfonate (SDBS) to core material), have a spherical core-shell structure. The wall material provides a cavity space that stably encapsulates the core material. Fire tests in confined spaces demonstrated that the heat-responsive PFMP@GE microcapsules in the UV-curable resin released PFMP under fire conditions, with changes in smoke gas concentrations and temperature further verifying that the flames were effectively extinguished. The core material's synergistic fire-extinguishing mechanism of the core material imparts active safety features to the UV-curable resin.

Leaf-adhesive pesticide microcapsules represent a promising approach to improving pesticide efficacy while minimizing environmental pollution. In this study, we developed a leaf-adhesive polyurethane microcapsule loaded with prochloraz (Pro@CS-OP-10) using a reactive emulsifier (OP-10) via interfacial polymerization. Physicochemical analysis revealed microcapsules with smooth surfaces and uniform distribution, averaging 1.97 μm in size, with an encapsulation efficiency of 96.38 %. Comparative assessments demonstrated superior wetting and adhesion properties of Pro@CS-OP-10 on wheat leaves compared to other commercial formulations. Moreover, the polyurethane shell effectively enhanced the photostability of encapsulated prochloraz and hindered its rapid release. Fungal growth rate experiments indicated prolonged inhibitory effects of Pro@CS-OP-10 on Fusarium graminearum, with median inhibitory concentrations (EC₅₀) on the second and eighth day being 0.018 mg/L and 0.045 mg/L. Therefore, the leaf-adhesive Pro@CS-OP-10 shows great potential as an environmentally friendly fungicidal formulation.

There are inorganic salts in glyphosate production liquor and natural water bodies coexisting with glyphosate. It is imperative to develop a salt-tolerant adsorbent for glyphosate in water. Industrial D113 resin undergone two-step transformation to optimize the preparation of D113 in-situ loaded with Fe³⁺ (D113-Fe³⁺) as salt-resistance glyphosate adsorbent. The loading amount of Fe³⁺ on D113-Fe³⁺ is 3.5 mmol/g. The adsorption mechanism revealed that Fe³⁺ in D113-Fe³⁺ formed Fe-O-P bond with the phosphonate group of glyphosate. At 293 K, the maximum complex ratio of the adsorbed glyphosate to Fe³⁺ in D113-Fe³⁺ was 2.4:1. At 293 K, the remarkable saturated glyphosate adsorption capacity of D113-Fe³⁺ reached 1420.2 mg/g. In pK₂ state of glyphosate, D113-Fe³⁺ featured its maximum adsorption capacity at the zero charge point 2.43 of D113-Fe³⁺ and 293 K. In glyphosate solution coexisting 0–16 % NaCl, D113-Fe³⁺ exhibited stable glyphosate adsorption capacity and salt-resistance compared with D201, D301 and 330 resin. The endothermic and spontaneous adsorption of glyphosate on D113-Fe³⁺ can fit Freundlich model and pseudo-second-order model. 2 mol/L NH₃·H₂O, 2 mol/L FeCl₃ and 2 mol/L H₂SO₄ could all regenerate D113-Fe³⁺. The characteristics of salt-resistance and the remarkable saturated adsorption capacity made D113-Fe³⁺ comparable to all reported glyphosate adsorbents.