Fluorine‐Containing Silsesquioxane‐Based Hybrid Porous Polymers Mediated by Bases and Their Use in Water Remediation

Abstract

Two different silsesquioxane-based porous polymers (FHPPs), namely FHPP-1 and FHPP-2, have been prepared, respectively, by changing the acid scavenger from sodium bicarbonate to triethylamine in the Heck reaction between octavinylsilsesquioxane (OVS) and 1,4-dibromotetrafluorobenzene. It was observed that defluorination occurred in the case of triethylamine. FHPP-1 possesses a higher surface area of 600 m g and a hierarchical porous structure; in contrast, FHPP-2 possesses a S value of 325 m g and a microporous structure. This work provides a new approach to the preparation and tuning of fluorine-containing porous polymers based on silsesquioxanes. These porous materials were employed to remove dyes and a heavy metal from water, showing good binding efficiencies.

Ferrocene‐Functionalized Silsesquioxane‐Based Porous Polymer for Efficient Removal of Dyes and Heavy Metal Ions

“…It was quite clear that the absorption behavioro f metal ions fitted well with the Langmuir isotherm model according to the values of R 2 ,a nd the maximum equilibrium absorptionc apacities calculated by the Langmuir isotherm model for Ni 2 + ,H g 2 + ,a nd Pb 2 + are 37, 191, and 328 mg g À1 ,r espectively.R elative to ferrocene-free silsesquioxane-based porous polymers, Fc-HPP exhibited excellent absorption of heavy metals. [30,45] In addition to its high surfacea rea, the polarity of ferroceneu nits favors the absorption of heavy metal ions owing to electrostatic interactions. For Pb 2 + ,t his value is comparable to other absorbents, [32, 42a, 46] as listed in Table S6 in the Supporting Information.…”

A Highly Effective Route to Si−O−Si Moieties through O‐Silylation of Silanols and Polyhedral Oligomeric Silsesquioxane Silanols with Disilazanes

“…Overall, silsesquioxanes (SQs) have been the object of considerable interest in recent times. [85][86][87][88] In contrast to the reactions of simple silanols, the O-silylation of SQs requiredt he utilizationo f Bi(OTf) 3 as an additional catalyst. [85][86][87][88] In contrast to the reactions of simple silanols, the O-silylation of SQs requiredt he utilizationo f Bi(OTf) 3 as an additional catalyst.…”

A POSS‐Phosphazene Based Porous Material for Adsorption of Metal Ions from Water

“…The broadening of these peaks suggests the formation of cross‐linked structure. The band at 3440 cm −1 is attributed to Si−OH fragments due to partial cleavage of Si‐O‐Si bonds of the cage POSS during the Heck reaction …”

“…In solid state 29 Si NMR spectrum (Figure a), the signals at −69.2 and −76.8 ppm are assigned to T 2 and T 3 units (T n is C‐Si(OSi) n (OH) 3− n ), and signals at −99.0 and −107.2 ppm suggest the formation of Q 3 and Q 4 units (Q n is Si(OSi) n (OH) 4− n ) due to partial cleavage of the POSS cyclic structure (Figure b). Similar cleavage of siloxane bonds of POSS units due to presence of bases, such as triethylamine or NaHCO 3 during Heck reaction was reported previously . However, the relative intensity ratio T 3 /(T+Q) is up to 0.57, which means that at least half cages in the network remain undamaged.…”

“…Ac omparatives tudy allows to detect Si-O-Si (1100 cm À1 )a nd PÀN( 1200 cm À1 )s egments arising from POSS and cyclo-phosphazeneu nits, respectively in the polymer.T he broadening of these peaks suggests the formation of cross-linked structure.T he band at 3440 cm À1 is attributedt o SiÀOH fragments due to partial cleavage of Si-O-Si bonds of the cage POSS during the Heck reaction. [57,58] In solid state 29 Si NMR spectrum (Figure 2a), the signals at À69.2 and À76.8 ppm are assigned to T 2 andT 3 units (T n is C-Si(OSi) n (OH) 3Àn ), and signals at À99.0 and À107.2 ppm suggest the formation of Q 3 and Q 4 units (Q n is Si(OSi) n (OH) 4Àn )d ue to partial cleavage of the POSS cyclic structure (Figure2b). Similar cleavage of siloxaneb onds of POSS units due to presence of bases, such as triethylamine or NaHCO 3 during Heck reaction was reported previously.…”