Strategies toward catalytic biopolymers: Incorporation of tungsten in alginate aerogels

Paraskevopoulou, Patrina; Gurikov, Pavel; Raptopoulos, Grigorios; Chriti, Despoina; Παπαστεργίου, Μαρία; Kypritidou, Zacharenia; Skounakis, Vassilis; Argyraki, Ariadne

doi:10.1016/j.poly.2018.07.051

Cited by 20 publications

(19 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5. In agreement with the literature, 20,37 the spectra of both native and X-Ca-alginate aerogels (Fig. 5 le) show the characteristic asymmetric and symmetric stretching vibrations of the carboxylate groups coordinated to Ca 2+ ions at 1603 cm À1 and 1419 cm À1 , the corresponding stretching vibrations of the C-O-C groups on the sugar ring at 1082 cm À1 and 1033 cm À1 , respectively.…”

Section: Chemical Characterization Of Native and Crosslinked Biopolymsupporting

confidence: 90%

“…Thermogravimetric analysis ( Fig. 9 le and S4 † le) revealed that the thermal decomposition of native alginate aerogels (G35 and G75) was very similar, especially at temperatures below 500 C, showing three weight loss steps: one at temperatures below 100 C, which can be assigned to water loss 20,65 (weight loss between 10-20%), another one at temperatures between 220 and 300 C (weight loss between 20-40%), and a third one at temperatures between 300 and 500 C (weight loss between 15- Table 1 Selected material properties of native (Ca-alginate and chitosan) and crosslinked (X-Ca-alginate and X-chitosan) biopolymer aerogel beads 20%). The residue at 800 C was between 10-28%.…”

Section: Chemical Characterization Of Native and Crosslinked Biopolymmentioning

confidence: 98%

“…Aerogels were invented in the early 1930's by Kistler 1,2 and are dened as solid colloidal or polymeric networks of nanoparticles expanded throughout their entire volume by a gas. 3,4 Early emphasis was based on silica and other inorganic aerogels, 1,2,5 while organic aerogels, based on organic polymers [6][7][8][9][10][11][12] or biopolymers, [13][14][15][16] and hybrid organic-inorganic aerogels [17][18][19][20][21] were developed later.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Polyurea-crosslinked biopolymer aerogel beads

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Chemical Characterization Of Native and Crosslinked Biopolymsupporting

confidence: 90%

Section: Chemical Characterization Of Native and Crosslinked Biopolymmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Polyurea-crosslinked biopolymer aerogel beads

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…[2]. Several types of aerogels have been reported, including inorganic [5,6,7,8,9], organic (based on biopolymers [10,11,12,13] or synthetic polymers [14,15,16,17]), and hybrid inorganic/organic [18,19,20,21,22].…”

Section: Introductionmentioning

confidence: 99%

Millimeter-Size Spherical Polyurea Aerogel Beads with Narrow Size Distribution

Chriti

Raptopoulos

Παπαστεργίου

et al. 2018

Gels

Self Cite

View full text Add to dashboard Cite

We report the room temperature synthesis of spherical millimeter-size polyurea (PUA) aerogel beads. Wet-gels of said beads were obtained by dripping a propylene carbonate solution of an aliphatic triisocyanate based on isocyanurate nodes into a mixture of ethylenediamine and heavy mineral oil. Drying the resulting wet spherical gels with supercritical fluid (SCF) CO2 afforded spherical aerogel beads with a mean diameter of 2.7 mm, and a narrow size distribution (full width at half maximum: 0.4 mm). Spherical PUA aerogel beads had low density (0.166 ± 0.001 g cm–3), high porosity (87% v/v) and high surface area (197 m2 g–1). IR, 1H magic angle spinning (MAS) and 13C cross-polarization magic angle spinning (CPMAS) NMR showed the characteristic peaks of urea and the isocyanurate ring. Scanning electron microscopy (SEM) showed the presence of a thin, yet porous skin on the surface of the beads with a different (denser) morphology than their interior. The synthetic method shown here is simple, cost-efficient and suitable for large-scale production of PUA aerogel beads.

show abstract

“…Because of attractive properties of silica aerogels (e.g., low values of thermal conductivity, very low density, high porosity, high surface area), those materials have found applications in space exploration [7,8], in nuclear reactors as Cerenkov radiation detectors [9,10,11], in catalysis [12,13], and in drug delivery [14,15]. Nowadays, several types of aerogels are known, including inorganic [16,17,18,19,20], organic (based on biopolymers [21,22,23,24] or synthetic polymers [25,26,27,28,29]), and hybrid inorganic/organic [30,31,32,33,34].…”

Section: Introductionmentioning

confidence: 99%

Poly(Urethane-Acrylate) Aerogels via Radical Polymerization of Dendritic Urethane-Acrylate Monomers

et al. 2018

Self Cite

View full text Add to dashboard Cite

The purpose of this work was to investigate the effect of multifunctionality on material properties of synthetic polymer aerogels. For this purpose, we present the synthesis and characterization of monolithic dendritic-type urethane-acrylate monomers based on an aliphatic/flexible (Desmodur N3300), or an aromatic/rigid (Desmodur RE) triisocyanate core. The terminal acrylate groups (three at the tip of each of the three branches, nine in total) were polymerized with 2,2′-azobis(isobutyronitrile) (AIBN) via free radical chemistry. The resulting wet-gels were dried with supercritical fluid (SCF) CO2. Aerogels were characterized with ATR-FTIR and solid-state 13C NMR. The porous network was probed with N2-sorption and scanning electron microscopy (SEM). The thermal stability of aerogels was studied with thermogravimetric analysis (TGA). Most aerogels were macroporous materials (porosity > 80%), with high thermal stability (up to 300 °C). Aerogels were softer at low monomer concentrations and more rigid at higher concentrations. The material properties were compared with those of analogous aerogels bearing only one acrylate moiety at the tip of each branch and the same cores, and with those of analogous aerogels bearing norbornene instead of acrylate moieties. The nine-terminal acrylate-based monomers of this study caused rapid decrease of the solubility of the growing polymer and made possible aerogels with much smaller particles and much higher surface areas. For the first time, aliphatic/flexible triisocyanate-based materials could be made with similar properties in terms of particle size and surface areas to their aromatic/rigid analogues. Finally, it was found that with monomers with a high number of crosslinkable groups, material properties are determined by multifunctionality and thus aerogels based on 9-acrylate- and 9-norbornene-terminated monomers were similar. Materials with aromatic cores are carbonizable with satisfactory yields (20–30% w/w) to mostly microporous materials (BET surface areas: 640–740 m2 g−1; micropore surface areas: 360–430 m2 g−1).

show abstract

Strategies toward catalytic biopolymers: Incorporation of tungsten in alginate aerogels

Cited by 20 publications

References 50 publications

Polyurea-crosslinked biopolymer aerogel beads

Polyurea-crosslinked biopolymer aerogel beads

Millimeter-Size Spherical Polyurea Aerogel Beads with Narrow Size Distribution

Poly(Urethane-Acrylate) Aerogels via Radical Polymerization of Dendritic Urethane-Acrylate Monomers

Contact Info

Product

Resources

About