Phytic acid (PA) was used as a dopant for polyaniline (PANI) to prepare a series of phytic acid-doped polyaniline composites (PA/PANI) by varying the doping mass ratio of PA to PANI (m(PA)/m(PANI)). Then PA/PANI were employed to fabricate an intelligent anticorrosive coating with photothermal conversion capability for self-healing. The dispersion of PA/PANI in the coating was investigated, and the influence of m(PA)/m(PANI) and PA/PANI loading (w(PA/PANI)) on the anticorrosive and self-healing properties of the coating was studied using scanning electron microscopy, electrochemical impedance spectroscopy, and neutral salt spray tests. Results demonstrate that the incorporation of PA/PANI significantly enhances the adhesion, anticorrosive performance, and self-healing capability of the coating, achieving a synergistic effect. When m(PA)/m(PANI) is 10 and w(PA/PANI) is 1%, the dispersion of PA/PANI in the coating is optimal, and the pull-off adhesion strength of the coating is increased from 2.06 MPa to 3.48 MPa. After immersion in a w=3.5% NaCl solution for 28 d, the low frequency impedance at 0.1 Hz(|Z|0.1 Hz ) of the intact coating is two orders of magnitude higher than that of the pure resin coating, and no corrosion is observed during the 800 h salt spray test. Following just 10 s of near-infrared light irradiation, the scratches on the coating surface almost completely disappear, and its barrier properties are effectively restored. As a result, it can withstand a 400 h neutral salt spray test, with the |Z|0.1 Hz value increasing from 6.58×105 Ω·cm2 to 2.25×108 Ω·cm2. In contrast, the scratch width of the pure resin coating remains largely unchanged, being accompanied by obvious signs of corrosion.
A combination of photopolymerization and emulsion templating method was used to prepare pH-responsive porous microspheres(8-HQ@pTM-DM)loaded with a corrosion sensing probe 8-hydroxyquinoline(8-HQ)in one step by introducing a pH-responsive monomer,dimethylaminoethyl methacrylate(DMAEMA).The effects of the addition of DMAEMA on the morphology and the release behavior of the porous microspheres were systematically investigated,and the effects of the pH-responsive microspheres on the coating warning performance and corrosion resistance were also examined.Results showed that the prepared porous microspheres 8-HQ@pTM-DM were pH-responsive,with the fastest release rate in acidic conditions.Functional coatings with corrosion warning and anti-corrosion properties were constructed by incorporating 8-HQ@pTM-DM into the resin,and the prepared coatings were responsive to Al3+ and could be used for early warning of corrosion of aluminum alloy substrates.The coating prepared with 8-HQ@pTM-DM microspheres showed a significant fluorescence warning effect on scratches,and the fluorescence intensity was more pronounced and the contrast and sensitivity were higher compared with that of the coating with non-responsive porous microspheres(8-HQ@pTMPTA).Meanwhile,due to the corrosion inhibitory effect of 8-HQ,the incorporation of 8-HQ@pTM-DM also improved the corrosion resistance of the coating.
Portulaca oleracea L.is a common plant which has received a lot of attention due to its superior antimicrobial properties.A nanofiber membrane loaded with Portulaca oleracea L.extract(POE)was prepared by electrospinning method using polyacrylonitrile(PAN)as raw material and N,N-dimethylformamide(DMF)as solvent.The nanofiber membrane morphology,chemical structure,mechanical properties,wettability,in vitro release properties,antioxidant and antimicrobial properties were characterized,and the antibacterial mechanism of PAN/POE nanofiber membranes was initially investigated.Results showed that the fiber diameter of the PAN/POE nanofiber membrane increased gradually with the increase of extract concentration,and the diameter was as high as(397.40±71.36)nm at POE mass fraction(w(POE))of 12%.The mechanical properties of the nanofiber membrane increased with the increase of w(POE),and the fracture strength was up to(11.76±0.46)MPa.In addition,the cumulative release of POE in the nanofiber membrane increased with the increase of w(POE),up to(93.59±2.22)%.The scavenging rate of 2,2-diphenyl-1-picrylhydrazyl(DPPH)radicals was up to(87.08±4.43)%.The inhibition circle diameters of Staphylococcus aureus and Escherichia coli were up to(12.42±1.70)mm and(16.76±0.49)mm,respectively.POE is able to destroy the bacterial cell membranes and thus achieve the bactericidal effects through fluorescence staining experiments and SEM observations.The PAN/POE nanofiber membrane has great potential in the field of wound dressing.
Carbonyl compound has attracted great interest as the electrode material of polymer rechargeable battery owing to its potentially low-cost,sustainable,fast electrochemical reaction kinetics and multi-electron transfer capabilities.Among various carbonyl compounds,anthraquinone has been widely investigated in the past few years due to its excellent electrochemical stability and unique aromatic properties.Common anthraquinone materials often suffer from loss of capacity due to their low electronic conductivity and solubility in the organic electrolyte,which negatively affect the rate performance and cycling stability.Therefore,it is still challenging to develop anthraquinone based electrode with superior electrochemical performance.Many strategies have been attempted to address the above issues.Among them,the polymerization has been proved to be an effective strategy to reduce the solubility.Moreover,incorporating conductive additive with high specific surface area to form composites has also been demonstrated as an efficient approach to suppress dissociation dissolution and improve the electron transport in electrodes.Herein,a novel composite electrode material poly1,5-anthraquinone-coated carbon nanotube(CNT@P15AQ)was prepared via facile in-situ polymerization.After polymerization,the stability of anthraquinone in the organic electrolyte is significantly improved.In addition,the introduction of CNT can construct long-range electron transport pathways.Satisfactorily,the first discharge specific capacity of CNT@P15AQ composite electrode with 29%CNT mass fraction can reach 241.7 mA·h/g at a current density of 50 mA/g,which is 1.44 times higher than that of P15AQ.Meanwhile,the CNT@P15AQ composite electrode also exhibits excellent rate performance and cycle stability,which exhibits a reversible specific capacity of 148.5 mA·h/g at 10 C and retains 84.7%of its initial discharge capacity after 100 cycles at 1 C.High-performance CNT@P15AQ composite electrode with simple preparation method provides a broad application prospect of the next generation of rechargeable battery based on polymer electrode.
As the electronics field is increasingly developing in the direction of high-speed transmission and high connection density,the copper clad laminates widely used in 5G equipment have technical requirements such as low dielectric constant,low dielectric loss,high thermal conductivity,high reliability,et al.Polytetrafluoroethylene(PTFE)copper clad laminates are widely used in high-frequency microwave circuits because of their excellent dielectric properties and chemical stability.However,the preparation of existing PTFE copper clad laminates has related problems in the whole chain of monomer purification,resin polymerization,filler modification,composite materials to product processing,which limits their practical applications.This paper summarizes the development process of copper clad laminates in recent years,and proposes methods to solve the performance of PTFE from the aspects of molecular design and sequence distribution control of high cohesive PTFE,controllable impurity content of the whole process of high purity PTFE and green industrialization technology,new filler preparation and surface treatment technology,composition and interface design of multi-phase and multi-component PTFE composite materials,processing rheology and structural uniformity control of copper clad laminates,etc.,so as to develop a system basic theory from the aspects of resin structure,filler modification,composite to molding processing,and the preparation of high-performance PTFE copper clad laminate.
