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The high internal phase emulsion (HIPE) template method is widely used to prepare porous functional materials because of its designable emulsion components and adjustable porosity. Herein, amphiphilic gelatin (GE) as the sole emulsion stabilizer, and no additional emulsifiers were added to prepare a stable GE‐HIPE membrane and its zeolitic imidazolate framework‐67 (ZIF‐67) hybrid composite membrane. The ZIF‐67/GE‐HIPE composite membrane has good lipophilicity by constructing dual micro‐nano structures by HIPE template and in situ growth of ZIF‐67. When ZIF‐67 was grown in situ, the water contact angle (CA) increased from 58.1 ± 2° for the GE membrane to 121 ± 1.9° for ZIF‐67/GE‐HIPE composite membranes. Besides, the minimum CA of organic solvent is 4.5 ± 0.7° (n‐hexane). The ZIF‐67/GE‐HIPE composite membranes exhibit good O/W emulsion separation properties and adsorption removal ability of organic pollutants. After 10 times of recycling emulsion separation, the emulsion separation capacity of the membrane was still greater than 99.4%. The lipophilic dye removal rate of the ZIF‐67/GE‐HIPE composite membrane was 2.37 times higher than that of GE‐HIPE, and the adsorption process conforms to the pseudo‐second‐order model. Thus, this work provides a strategy for the preparation of GE‐based hydrophobic modified membrane and also presents a typical treatment of adsorption‐separation of lipophilic substances. [ABSTRACT FROM AUTHOR]

The current study reports the utilization of MIL‐100(Fe) as Pickering emulsifiers to stabilize CO2‐in‐water high internal phase emulsions, thereby synthesizing interconnected macroporous hybrid monoliths with adjustable pore sizes. During such a green synthesis procedure, the influences of Fe‐MOF type and content, carbon dioxide density, and the amount of crosslinker have been explored respectively. The as‐synthesized MOF‐containing poly(HIPE)s were characterized by FT‐IR, XRD, SEM, CLSM, and TGA. The morphology of the monoliths was mainly observed by EDS‐mapping and SEM, which showed that Fe‐MOFs were uniformly distributed into the monolithic matrix and the void sizes and interconnected pore sizes were 20 to 150 μm and 5 to 50 μm, respectively. Furthermore, the MIL‐100(Fe)‐containing monoliths exhibited an excellent elasticity and can quickly return to their original state when reaching up to 90% compressive strain without failing. To evaluate the adsorptive properties of the composite monoliths, the immobilization of β‐amylase on the obtained monoliths was studied. The results of immobilized enzymes showed that the highest protein adsorption rate can reach 55% and the immobilization efficiency can reach 89%. Since our synthetic route is clean and controllable, biocompatible monoliths with good elasticity and toughness were prepared, which presents a viable strategy to produce hybrid monoliths for bio‐medical applications. [ABSTRACT FROM AUTHOR]

Abstract Macroporous poly(N -methylol acrylamide)–high internal phase emulsion [poly(NMA)HIPE] composite monoliths were prepared by carbon dioxide-in-water (CO 2 /W) emulsions using metal-organic framework (MOF) Cu-BDC (BDC = 1,4-dicarboxybenzene) as stabilizer. The composite monoliths were characterized using XRD, SEM, EDS-mapping, FT-IR, TG, and mercury injection methods. Increasing the internal phase fraction would lead to the decrease of monolith density and the increase of void size, and it is favorable for the formation of macroporous interconnected structure with low density and porosities up to 81.6%. The mechanical properties of the Cu-BDC/poly(NMA)HIPE and Cu-BDC removal were also evaluated. The composite polyHIPEs exhibited high antibacterial activity against Escherichia coli. The presented approach facilitated the clean manufacture of open-celled MOF based scaffolds in a one-pot process with porosity of up to 82%. Graphical abstract Image 1 Highlights • Composite HIPE Monoliths obtained via C/W HIPE Emulsions. • The volatile organic solvent is avoided. • Exhibited a high compressive stress of 2.2 MPa and 91.5% strain. • Exhibited antibacterial activity against Escherichia coli. • A coordination polymer uniformly dispersed in PolyHIPE. [ABSTRACT FROM AUTHOR]

Designing efficient nanoparticle-based stabilizer that is suitable for achieving an interconnected porous monolith still remains a challenge. Herein, Ag-nanocomposite poly high-internal phase emulsion (HIPE) template was readily obtained by O/W HIPE, co -stabilized by silver nano powders (Ag-NPs) and polyvinyl pyrrolidone. Cyclohexane as oil phase, N, N ′-methylenebisacrylamide as a crosslinking agent, and free-radical copolymerization of acrylamide (AM) and 2-acrylamide-2-methyl propane sulfonic acid (AMPS) were used in the water phase, which was initiated by potassium persulfate. Thus, Ag-nanocomposite copolymer poly(HIPE)s [Ag/P(AM- co -AMPS)] were obtained via a one-pot synthesis method. The effects of Ag-NP content and different internal phase volume on the porous composites were investigated. The morphology and structures of the composites were characterized, and the average pore size was measured to be approximately 60 μm. Furthermore, the catalytic activity was studied via catalytic degradation of the methylene blue (MB). The decolorization of the MB solution can be completed within 8 min by using the composites containing 5 wt% Ag-NPs. The composite poly(HIPE)s had certain antibacterial activity against E. coli and S. aureus bacteria (9 mm zone of inhibition). Moreover, a compression electric sensitivity (GF = 2.05) was exhibited with an enhanced electrical conductivity. Thereby, a facile approach to multifunctional macroporous Ag-nanocomposite poly(HIPE) was presented. [Display omitted] • PVP/Ag was firstly developed to construct multifunctional poly(HIPE) foam. • It exhibited a higher gauge factor of 2.05 when 0.5% Ag content was added. • It behaves with faster catalytic efficiency within 8 min. • The morphology and performance of the composites can be tailored by the emulsion composition. [ABSTRACT FROM AUTHOR]

Herein, Cu-BDC/poly(N -methylol acrylamide- co -sodium allyl sulfonate) [Cu-BDC/P(NMA- co -SAS)] macroporous foam was synthesized templating from CO 2 -in-water (C/W) high internal phase emulsions (HIPEs), and using Cu-BDC as Pickering emulsifier. The features of the macroporous monolith, such as structure and void diameter, can be adjusted by changing the emulsion composition. The resultant macroporous foams have a low bulk density (0.317 g cm−3), high porosity (79.60 %), suitable pore volume (3.956 cm3 g-1), and pore size ranging from 5.46 μm to 36.47 μm. The maximum swelling degree of 20.7 g/g for the composite foam was obtained when a high MBAM dosage of 12.5 wt% was used. Moreover, adsorption behavior and antibacterial property of the composite foam with 5.0 wt% Cu-BDC were investigated. The results proved that the obtained foam could behave as a potential multi-functional antibacterial material. [ABSTRACT FROM AUTHOR]

Because of the nontoxic solvents contained in CO2-in-water emulsions, porous polymer composites templated from these emulsions are conducive for bio-applications. Herein, bio-active rod-like calcium-organic framworks (Ca-BDC MOFs, BDC= 1,4-benzenedicarboxylate anion) particles co-stabilized CO2-in-water high internal phase emulsion (C/W HIPE) in the presence of polyvinyl alcohol (PVA) is first presented. After curing of the continuous phase, followed by releasing CO2, integral 3D macro-porous Ca-BDC monolith and Ca-BDC/Poly(2-hydroxyethyl methacrylate-co-acrylamide) HIPEs monolithic composites [Ca-BDC/P(AM-co-HEMA)HIPEs] with open-cell macro-porous structures were successfully prepared. The pore structure of these porous composite can be tuned by means of tailoring the Ca-BDC dosage, carbon dioxide pressure, and continuous phase volume fractions in corresponding C/W HIPEs. Results of bio-compatibility tests show that these Ca-BDC/P(AM-co-HEMA)HIPEs monoliths have non-cytotoxicity on HepG2 cells; also, the E. coli can grow either on the surfaces or inside these monoliths. Furthermore, immobilization of β-amylase on these porous composite presents that β-amylase can be well-anchored into the porous polymer composites, its catalytic activity can be maintained even after 10 cycles. This work combined bio-active MOFs Ca-BDC, bio-compatible open-cell macroporous polymer PAM-co-HEMA and green C/W HIPEs to present a novel and facile way to prepare interconnected macro-porous MOFs/polymer composites. Compared with the existing other well-known materials such as hydrogels, these porous composites possess well-defined tunable pore structures and superior bio-activity, thereby have promising applications in bio-tissue engineering, food, and pharmaceutical. [ABSTRACT FROM AUTHOR]

According to the applications of materials in food and biology etc. fields, the open-cell macroporous polymer composite must contain a non-toxic component, and be bio-compatible, and the preparation processes should be green and facile. Herein, bio-compatible macro-porous nano-hydroxyapatite particles (n-HAPs)/polymer monolithic composites were templated from green and facile CO 2 -in-Water high internal phase emulsion (C/W HIPE). The bio-active n-HAPs that acted as emulsifiers were incorporated, which enable the well-dispersion of functional fillers in these monolithic composites. Green and facile C/W HIPE templating combined with radical polymerization of bio-compatible monomers involves nontoxic chemicals, and produced polymer monolith with macro-porous open-cell structure (80–120 μm in pore size, 20–40 μm in pore-throat size), and enable the n-HAPs/polymer improved flexibility and mechanical performance (above 80% compression strain, > 400 kPa of compression strength). Results of bio-compatibility tests show that these n-HAPs/polymer monoliths have non-cytotoxicity on HepG2 cells; Furthermore, the immobilization of pectinase by the composite indicates that composites have physical adsorption of pectinase, and the introduction of n-HAPs is more conducive to the immobilization of pectinase and the improvement and maintenance of enzyme activity; after reusing the immobilized pectinase 10 times, the relative catalytic activity can still be above 85%. Therefore, this kind of porous composite has promising potential in applications of bio-tissue engineering, food, and pharmaceutical. [Display omitted] • Nano-hydroxyapatite inserted monolith was firstly obtained via C/W HIPEs. • n-HAPs particles can high-effectively stabilize C/W HIPE. • It exhibited compressive stress of 0.52 MPa and 80% strain under 5 N of force. • It can immobilization of pectinase effectively. • Immobilized pectinase still retains a relative catalytic activity of 85% after reuse. [ABSTRACT FROM AUTHOR]