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In the case of bonding of aluminum alloy, surface pretreatment have been widely adopted for adherends so as to achieve superior adhesive performance. However, the strict surface treatment of the aluminum alloy cannot be implemented without special equipment and the mechanical properties, corrosion resistance and aging resistance of the common adhesives cannot meet the demand without surface treatment. Here, acrylic oligomer modified by carboxyl terminated organosilicon and nano alumina were used to modify an epoxy formulation based on a classical DGEBA monomer to produce a high peel strength epoxy adhesive that can be used without surface pretreatment. The peel strength and the shear strength of the adhesive could reach 7.18 N/cm and 18.75 MPa, respectively, and could be well maintained under −70 °C and 100 °C. The novel adhesive also has good heat aging resistance, water resistance and artificial seawater resistance. SEM and XPS were used to investigate mechanism of aging resistance of modified adhesives without surface treatment. [ABSTRACT FROM AUTHOR]

• Synthesis of a novel U (VI) adsorbent HCP-Phenylalaninol (HCP-PAO), a porous hypercrosslinked aminol. • The hypercrosslinked product is simple to synthesize and shows porosity, large surface area and good thermodynamic stability properties. • HCP-PAO shows efficient U (VI) adsorption performance (Q e = 369.5 mg/g, pH = 7) and long service life. • HCP-PAO shows good selective toward uranium at simulated seawater. Uranium mining from seawater has sparked a lot of research curiosity. Here, we synthesized a porous hypercrosslinked phenylalaninol (HCP-PAO) for U (VI) adsorption from water, in which phenylalaninol bearing amino and hydroxyl groups was used as the monomer, and biphenyl dichlorobenzyl (BCMP) was used as the external crosslinker. The resulting porous adsorbent has a surface area of 562.6 m2/g and a pore volume of 0.41 cm3·g−1. The pore size distribution is focused around 3–4 nm, indicating that it is a typical mesoporous polymer. The adsorbent had the most promising adsorption performance at pH = 7, reaching adsorption saturation in a 100-ppm uranium-doped solution for 2 h (adsorption capacity of 369.5 mg/g). HCP-PAO was particularly sensitive to uranium in complicated settings (56.3 % removal rate), and the adsorption mechanism closely resembled the Langmuir model and the pseudo-second-order model well. The practically consistent adsorption capacity of the HCP-PAO after five adsorption/resolution studies indicated its high recyclability. The mechanism of uranium extraction by HCP-PAO is the synergistic coordination of –NH 2 and –OH with U (VI). HCP-PAO had an adsorption capacity higher than 100 mg/g at pH = 8 which is close to the pH of natural seawater, and showed good selectivity for U (VI) in simulated seawater experiments (removal rate over 55 %). Our research suggests that the novel hypercrosslinked product HCP-PAO can be applied as an adsorbent to efficiently capture U (VI) from water, and also it has great potential in seawater uranium extraction as well as expanding the research concept of porous uranium adsorbent. [ABSTRACT FROM AUTHOR]

Herein, a novel amidoxime functionalized metal organic framework (MOF)-based adsorbent named PCN-222-AO was obtained by grafting amidoxime groups on the surface of PCN-222 through amination, cyanylation and amidoximation modification reactions successively. The PCN-222-AO exhibited outstanding adsorption capacity (432.7 mg·g−1), selectivity and reusability in U(VI) adsorption at pH = 7.0, and showed superb adsorption performances in the simulated and real seawater. The XPS spectra and adsorption energy calculations confirmed the C N (H 2 TCPP), C=N-OH and -NH (2) groups served a vital role in the U(VI) adsorption process. PCN-222-AO illustrated excellent antibacterial property, anti-biofouling activity and environmental safety, which effectively reduced the negative impacts of bacteria (E. coli and S. aureus) and Halamphora upon the U(VI) adsorption capacity and complied with the requirements for non-toxicity and innocuousness in the adsorbent application. The excellent antibacterial property and anti-biofouling activity may be attributed to Zr 6 cluster and abundant functional groups in the PCN-222-AO. Undoubtedly, the molecular structure design and construction of effective adsorbents are crucial for the U(VI) resource recovery. As first reported in this study, PCN-222-AO is a promising adsorbent to recover U(VI) from seawater, providing a new idea about the molecular structure design and construction of novel high-efficiency adsorbent. [Display omitted] • Novel adsorbent named PCN-222-AO was synthesized based on molecular structure design. • PCN-222-AO exhibited distinguished antibacterial activity and recycling ability. • PCN-222-AO showed excellent U(VI) adsorption capacity, Q e reached 432.7 mg·g−1. • Mechanism was the co-effect of coordination and electrostatic interaction. • The adsorbent possessed great potential to efficiently recover U(VI) from seawater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carboxyl and amidoxime bifunctional polymer was grafted on MIL-101 via surface initiated ATRP; • Highly efficient uranium adsorbent, adsorption capacity reached 1086 mg·g−1; • Synergistic effect of carboxyl and amidoxime groups promote uranium adsorption; • High uranium selectivity and reusability of adsorbent in simulated seawater. Nuclear energy can effectively alleviate the carbon emission problem caused by fossil fuels. Herein, a highly effective uranium adsorbent MIL-101-SMA-AO modified with carboxyl and amidoxime groups was prepared by a surface-initiated atom transfer radical copolymerization (ATRP) of styrene and maleic anhydride on MIL-101 (Cr) and the subsequent amidoximation. MIL-101-SMA-AO shows ultra-high BET specific surface area (greater than1300 m2∙g−1) and high efficiency adsorption performance, the maximum uranium adsorption capacity reached 1086 mg·g−1. It also shows high selectivity for U (VI) in a simulated seawater and excellent recyclability, the uranium adsorption capacity slightly dropped after five adsorption/desorption cycles. The affecting factors of uranium adsorption process were investigated by batch adsorption experiments under different adsorption conditions. Besides, the results of adsorption kinetics and thermodynamics show that the adsorption process of MIL-101-SMA-AO on U (VI) is controlled by chemical rate and is monolayer adsorption. The synergistic effect of carboxyl and amidoxime groups on the strong chelation with uranium were thought to afford the adsorbent high adsorption property and selectivity for uranium. MIL-101-SMA-AO provides a valid and promising program for the study of uranium extraction from seawater. [ABSTRACT FROM AUTHOR]

Benzil was hypercrosslinked to produce a novel hypercrosslinked porous organic polymer skeleton (HCP-CO) with an ultrahigh Brunauer-Emmett-Teller (BET) surface area of 605.4 m2·g−1. The skeleton was grafted with diaminomaleonitrile (DAMN) via a simple Schiff base reaction, and then reacted with hydroxylamine hydrochloride (NH 2 OH·HCl) to produce an amidoxime-modified hypercrosslinked benzil polymer (HCP-AO) possessing many amidoxime groups. The chelation of the amidoxime group and uranium (VI) and porous structure provided HCP-AO with excellent adsorption performance. The maximum adsorption capacity for the uranium of HCP-AO can reach 370.9 mg·g−1 at pH = 6. Moreover, the adsorption process agreed well with the Langmuir and pseudo-second-order models, thus indicating it was monolayer chemical adsorption. HCP-AO demonstrated excellent selectivity and recyclability; furthermore, the removal rate for uranium still remained at 66.35% in the coexistence of metal ions in simulated seawater. Furthermore, after five adsorption–desorption cycles, the adsorption capacity of HCP-AO slightly reduced. To summarize, we synthesized an efficient adsorbent that possesses high adsorption capacity, selectivity, and recyclability; it has good potential for uranium extraction from water. [Display omitted] • A novel amidoxime-modified hypercrosslinked polymer HCP-AO are prepared for uranium adsorption. • HCP-AO shows good uranium adsorption capacity of 370.9 mg/g. • Excellent uranium adsorption selectivity in simulated seawater. [ABSTRACT FROM AUTHOR]

Here, copoly (styrene / maleic anhydride) was hypercrosslinked using a simple Friedel–Crafts acylation reaction to produce a novel porous hypercrosslink polymer bearing carboxy groups (C-SMA). As a support, C-SMA was loaded with Fe 3 O 4 through a solvothermal method to produce a magnetic uranium adsorbent (Fe 3 O 4 @C-SMA), which was systematically characterized using FT-IR, TGA, SEM, XRD, VSM, BET, and XPS. Uranium adsorption was carried out by using Fe 3 O 4 @C-SMA under different conditions to evaluate its uranium adsorption capacity. The adsorbent shows good uranium adsorption performance (178 mg·g−1 at pH = 6), has excellent stability, and can be readily magnetically recovered. The porous framework of C-SMA avoided the magnetic agglomeration effect of bare Fe 3 O 4. XPS analysis indicates that both the carboxy groups and Fe 3 O 4 contribute to the uranium adsorption on Fe 3 O 4 @C-SMA. [Display omitted] • A novel hypercrosslinked material was prepared by Friedel–Crafts acylation reaction. • Fe 3 O 4 was loaded on hypercrosslinked polymer through solvothermal method. • Magnetic recovery and reusable uranium adsorption material. • High selective uranium adsorption selectivity in simulated seawater. [ABSTRACT FROM AUTHOR]

Here, reaction of a chloromethylated metal-organic framework (MOF) MIL-101 with diaminomaleonitrile (DAMN) following with an amidoximation reaction successfully produced a novel amidoxime functionalized porous material (MIL-101-AO). The chelation of amidoxime group to uranium and the large specific surface area afforded MIL-101-AO excellent selective adsorption ability for U (VI) in aqueous solutions (586 mg·g−1). Furthermore, MIL-101-AO showed much stronger selective adsorption for U (VI) than other co-existing metallic ions in the artificial seawater (removal rate reached 96%). The influence factors on the adsorption process were evaluated by batch adsorption experiments under different condition. The process of adsorbing uranium on MIL-101-AO fitted with the Langmuir model and the pseudo-second-order kinetic model. The △H° and △G° values of uranium adsorption indicated that it was an endothermic heat process; a higher adsorption temperature could promote the adsorption on MIL-101-AO. All the experimental results indicated that MIL-101-AO was an adsorbent with the application value of extracting uranium in seawater. • Amidoxime was first grafted on chloromethylated MIL-101 via diaminomaleonitrile. • Amidoxime-modified MIL-101 shows high U(VI) sorption capacity of 586 mg/g. • High selectivity, U(VI) removal rate reaches 96% in artificial seawater. • Large surface area and strong chelating ability play important role. [ABSTRACT FROM AUTHOR]