Hexadecyltributylphosphonium Bromide Research Articles

Facile synthesis of surfactant-modified layered double hydroxide magnetic hybrid composite and its application for bisphenol A adsorption: Statistical optimization of operational variables

A novel hexadecyltributylphosphonium bromide modified magnetic composite based on calcined Ni-Mn layered double hydroxide (HDTBP@Fe3O4@NiMn-CLDH) was synthesized and evaluated for the removal of bisphenol A (BPA) from aquatic media. The structural features of the synthesized hybrid material were determined by Fourier transform infrared (FTIR) spectroscopy, vibrating-sample magnetometer (VSM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray analysis (EDX). Response surface methodology (RSM) was used to investigate the influences of operational variables and optimize the adsorption process. The BPA adsorption process was developed by considering a central composite design (CCD) under RSM with four independent variables (initial BPA concentration (Co), agitation time, initial pH, and adsorbent dosage). From the statistical results, the optimal adsorption conditions for Co, agitation time, initial pH, and adsorbent dosage were determined as 22.53 mg/L, 80.05 min, 7.07, and 1.14 g/L, respectively, and under these conditions, the maximum yield was obtained as 86.85%. The kinetic study results showed the kinetic data was perfectly represented by the pseudo-second-order model. Furthermore, the isotherm data fitted very well to the Langmuir and Dubinin-Radushkevich (D-R) models. Additionally, the results based on the adsorption thermodynamics indicated that the process was spontaneous and endothermic. The findings of the present work indicate that RSM is suitable for optimization of the BPA adsorption process onto HDTBP@Fe3O4@NiMn-CLDH and the synthesized composite has great application potential for the remediation of water polluted with organic contaminants like BPA.

A kaolinite-tetrabutylphosphonium bromide intercalation compound as an effective intermediate for intercalation of bulky organophosphonium salts

A kaolinite-tetrabutylphosphonium bromide (TBPBr) intercalation compound (Kaol-TBPBr) underwent intercalation of dodecyltributylphosphonium bromide (C12TriBPBr), while a kaolinite-dimethyl sulfoxide (DMSO) intercalation compound (Kaol-DMSO) and methoxy-modified kaolinite (MeO-Kaol) showed no such capability. As for the reaction of Kaol-TBPBr and C12TriBPBr, the X-ray diffraction (XRD) patterns revealed expansion of the basal spacing from 1.53 nm of Kaol-TBPBr to 2.10 nm. Fourier transform infrared, solid-state 13C nuclear magnetic resonance (NMR) with cross polarization and magic angle spinning (13C CP/MAS NMR) spectroscopies and the C/P and the Br/P molar ratios indicated intercalation of C12TriBPBr between the layers of kaolinite upon removal of the pre-intercalated TBPBr. As concerns the reactions of Kaol-DMSO and C12TriBPBr, the XRD patterns exhibited no difference as compared to that of Kaol-DMSO or the decrease in basal spacing from the 1.12 nm of Kaol-DMSO to the 0.72 nm of pristine kaolinite. With respect to the reactions of MeO-Kaol with C12TriBPBr, the XRD patterns displayed no expansion of the basal spacing from 0.86 nm of MeO-Kaol. Kaol-TBPBr was also used as an intermediate for successful intercalation of relatively bulk organophosphonium salts, hexadecyltributylphosphonium bromide, tetradecyltrihexylphosphonium chloride and tetraoctylphosphonium bromide. These results clearly reveal the versatility of Kaol-TBPBr as an effective intermediate for use in kaolinite intercalation chemistry.

Synthesis and characterization of antibacterial bio-nano films for food packaging

This study prepared antibacterial nanocomposite films for food packaging from Montmorillonite, which was modified by quaternary ammonium salts such as cetyltrimethylammonium bromide (CT), hexadecyl-tributyl phosphonium bromide (HD) and corn starch (CS). After this, it determined the antimicrobial activity of CS nanofilms against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria. Dispersion of silicate layers and starch nanocomposite films was analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), and the results indicated that presence of quaternary ammonium salts enhanced clay dispersion, and the starch films incorporated with quaternary ammonium salts would provide potential use in food packaging as nanostructural materials. The nanofilms that were obtained based on the results of the antibacterial analysis were confirmed to have much stronger antibacterial properties than those in similar studies in the literature.

Effect of CEC coverage of hexadecyltributylphosphonium modified montmorillonite on polymer compatibility

The present work was aimed to investigate polymer compatibility of hexadecyltributylphosphonium bromide (HDTBPh) modified Na-montmorillonite (NaMt) at different cation exchange capacity (CEC) coverages. The NaMt was modified at five different CEC coverages in the range of 60%–150%. The morphology, porosity, and thermal and surface properties of HDTBPh in NaMt interlayer were investigated. The intercalation behavior of HDTBPh investigated by X-ray diffractometry showed that the d001-value reached a maximum of 23.4Å at 125% CEC coverage. The specific surface area (SSA) and porosity were investigated by N2 adsorption at −197°C temperature. The SSA decreased from 57.19m2/g to 24.11m2/g at 150% CEC coverage, as opposed to the porosity which increased upon interaction with HDTBPh and led to a more open structure. The thermal stability, investigated by themogravimetry (TGA), slightly decreased with increasing CEC coverage. The CEC coverage of HDTBPh was found to play an important role in the clay-polymer compatibility. A simple acid–base approach involving the calculation of total energy of interaction between NaMt surface and polymer surface (ΔGClay/Polymer/ClayIF) was developed to evaluate the clay-polymer compatibility. While the positive value of ΔGClay/Polymer/ClayIF indicated the clay-polymer compatibility, the negative value was ascribed to no polymer compatibility. The calculated value of ΔGClay/Polymer/ClayIF was critical for proper selection of CEC coverage for each polymer.

Effect of Surface Modification of Palygorskite on the Properties of Polypropylene/Polypropylene-g-Maleic Anhydride/Palygorskite Nanocomposites

The effect of surface modification of palygorskite (Pal) on filler dispersion and on the mechanical and thermal properties of polypropylene (PP)/polypropylene grafted maleic anhydride (PP-g-MAH)/palygorskite (Pal) nanocomposites was evaluated. A natural Pal mineral was purified and individually surface modified with hexadecyl tributyl phosphonium bromide and (3-Aminopropyl)trimethoxysilane; the pristine and modified Pals were melt-compounded with PP to produce nanocomposites using PP-g-MAH as compatibilizer. The grafting of Pal surface was verified by FT-IR and the change in surface hydrophilicity was estimated by the contact angle of sessile drops of ethylene glycol on Pal tablets. The extent of Pal dispersion and the degree of improvement in both the mechanical and thermal properties were related to the surface treatment of Pal. Modified Pals were better dispersed during melt processing and improved Young’s modulus and strength; however, maximum deformation tended to decrease. The thermal stability of PP/PP-g-MAH/Pal nanocomposites was considerably improved with the content of modified Pals. The degree of crystallinity increased with Pal content, regardless of the surface modification. Surfactant modified Pal exhibited better results in comparison with silane Pal; it is possible that longer alkyl chains from surfactant molecules promoted interactions with polymer chains, thereby improving nanofiller dispersion and enhancing the properties.

Evaluation of Thermal Properties of Nanocomposites Based on Ecobras Matrix and Vermiculite Modified with Alkylphosphonium Salt

SummaryThe use of biodegradable polymers to produce nanocomposites with mineral fillers leads to the production of new materials with low cost and reduced environmental impact, combined with improvements in mechanical and thermal properties. Nanocomposites based on poly(butylene adipate‐co‐terephthalate) and starch blend (Ecobras) and vermiculite (VMT) modified with hexadecyltributylphosphonium bromide (P‐VMT) were prepared by melt intercalation in a mixing chamber at 140 °C, keeping the amount of clay at 4%wt. The intercalation of P‐VMT in Ecobras was characterized by X‐ray diffraction (XRD) and infrared spectroscopy (FTIR). VMT organophilization was confirmed by the appearance of FTIR bands characteristic of the long alkyl chain of the phosphonium salt used and also by displacement of the basal peak towards lower 2θ values in the diffractogram compared to pure vermiculite. The thermal properties of Ecobras and its compositions were characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The addition of VMT and P‐VMT in Ecobras increased the crystallization temperature (Tc) and crystalline melting temperature (Tm), as observed by DSC analysis. The result of the thermogravimetric analysis showed that the addition of P‐VMT in Ecobras improved thermal stability of the nanocomposite. The Young's modulus of the composite with 4 wt% of P‐VMT indicated an increase in stiffness compared to the pure matrix.

ChemInform Abstract: Surfactant‐Thermal Method to Synthesize a Novel Two‐Dimensional Oxochalcogenide.

AbstractMn3Sb4S8(OH)2 (N2H4)2 is synthesized by reaction of Mn powder, Sb2S5, sulfur, N2H4·H2O, and hexadecyltributylphosphonium bromide as surfactant (autoclave, 175 °C, 7 d; 23% yield).

Investigation of adsorption behavior of phosphonium salts onto Na-montmorillonite

Montmorillonite is an important clay mineral due to its cation exchange capacity and technological properties such as swelling and gelling index etc. and, has been widely used in many scientific applications like organoclay. Meanwhile, adsorption themed studies with montmorillonite which depend on ion exchange processes by means of a variety of organic compounds like ammonium and phosphonium salts which are becoming very popular because of their usages in organoclay and polymer nanocomposites due to their higher thermal strengths. In this purpose, different types of phosphonium salts, namely Hexadecyl Triphenyl Phosphonium Bromide (HTPB), Hexadecyl Tributyl Phosphonium Bromide (HTBPB), and Tetraphenyl Phosphonium Bromide (TPB), were used to investigate the effect of these surfactants on the adsorption behavior of Na-montmorillonite. The last one was composed only of one aromatic head without an organic chain (TPB), whereas the others are in an organic chain with three branches (HTBPB) and an organic chain including one aromatic head (HTPB). The adsorption properties of these surfactants on the sample were also supported with the surface characterization tests, the zeta potential, surface tension, and flocculation measurement. The results clearly indicated that the adsorption behavior of these surfactants depend on their structure.

Growing Crystalline Zinc-1,3,5-benzenetricarboxylate Metal–Organic Frameworks in Different Surfactants

Six new zinc-1,3,5-benzenetricarboxylate-based metal-organic frameworks (MOFs) have been successfully synthesized using three different surfactants (PEG 400, octanoic acid, and hexadecyltributylphosphonium bromide) as reaction media. These surfactants with different characteristics, such as being neutral, acidic, and cationic, have been demonstrated to show strong effects on directing the crystals' growth and resulted in different secondary building units (SBUs) including an unusual SBU unit [Zn4(μ4-O)(CO2)7]. Our results clearly indicated that the surfactant-thermal method could offer exciting opportunities for preparing novel MOFs or other inorganic crystalline materials with diverse structures and interesting properties.

Surfactant–Thermal Method to Synthesize a Novel Two‐Dimensional Oxochalcogenide

A new two-dimensional (2D) oxosulfide, (N2H4)2Mn3Sb4S8(μ3-OH)2 (1), has been successfully synthesized under surfactant-thermal conditions with hexadecyltributylphosphonium bromide as the surfactant. Compound 1 has a layered structure and contains a novel [Mn3(μ3-OH)2]n chain along the b-axis. The photocatalytic activity for compound 1 has been demonstrated under visible-light irradiation and continuous H2 evolution was observed. Our results indicate that surfactant-thermal synthesis could be a promising method for growing novel crystalline oxochalcogenides with interesting structures and properties.

Mixed Micellization Properties of Cationic Monomeric and Gemini Surfactants

Mixed micellization properties of the cationic monomeric surfactants hexadecyltrimethylammonium bromide (CTAB), hexadecyltriphenylphosphonium bromide (CTPB), hexadecyltributylphosphonium bromide (CTBuPB), and tetradecyltriphenylphosphonium bromide (TTPB) with gemini surfactant C16H33(CH2)2N+(CH2)10N+(CH2)2C16H33·2Br− (C16-10-C16·2Br−) have been investigated by performing conductivity measurements in aqueous solution. The conductance data were used to obtain the values of the critical micelle concentration (cmc) of mixed surfactant systems having different compositions. The mixed cmc values determined from the experimental data were used to calculate the interaction parameter (β) using regular solution theory for the mixed surfactant system. The cmc values show nonideality, and the negative values of β indicate an overall attractive force in the mixed state. Also, the measured values of the excess free energy of mixing have negative values for all of the systems.

Thermal stability and long-acting antibacterial activity of phosphonium montmorillonites

Na-montruorillonite (Na-MMT) was exchanged with three quaternary alkylphosphonium salts: decyl tributylphosphonium bromide (DTBPBr), dodecyl tributylphosphonium bromide (DDTBPBr) and hexadecyl tributylphosphonium bromide (HDTBPBr), to investigate the effects of phosphonium salts species and relative molecular mass on the characteristics, morphology, thermal stability and long-acting antibacterial property of phosphonium montmorillonites. The resulting modified montmorillonites were characterized by the FTIR, XRD, TEM, and TG/DTG techniques. And minimum inhibitory concentration (MIC) was used to investigate antibacterial activity. The results show that the phosphonium salts are intercalated into Na-MMT, and the basal spacing of P-MMTs is enlarged with the increase of phosphonium salt content or the growth of alkyl chain length. DDTBP-MMT-3 with 19.83% (mass fraction) of dodecyl tributylphosphonium salts, displays excellent thermal stability and long-acting antibacterial activity.

Dynamic Solvation in Phosphonium Ionic Liquids: Comparison of Bulk and Micellar Systems and Considerations for the Construction of the Solvation Correlation Function, C(t)

Dynamic solvation of the dye coumarin 153 is studied in a phosphonium ionic liquid: hexadecyltributylphosphonium bromide, [(C4)3C16P+][Br-]. It forms micelles in water, and the bulk also exists as a liquid under our experimental conditions. This system permits a comparison with an imidazolium ionic liquid studied earlier, which also formed micelles in water (J. Phys. Chem. A 2006, 110, 10725-10730). We conclude that our analysis of the comparable situation in a phosphonium liquid is not as definitive as we had proposed earlier, i.e., that the majority of the early-time solvation arises from the organic cation. Part of the difficulty in performing this analysis is most likely due to the amount of water that is associated with the micelle. In the course of this work, we have focused on the calculation of the solvation correlation function, C(t), and investigated how it depends upon the methods with which the "zero-time" spectrum is constructed.

Morphology, thermal, and viscoelastic properties of poly(glycidyl methacrylate- co-methyl methacrylate)-based nanocomposites with various organo-modified clays

New nanocomposites of poly(glycidyl methacrylate- co-methyl methacrylate) (PGM) cured with cyclohexanedicarboxylic anhydride (CDCA) and layered silicates of inorganic content 3 and 5 wt% were prepared by casting the solution of the mixture and subsequent cross-linking at finally 200 °C. Non-modified montmorillonite (MMT) and organo-MMTs (ODA-M, ALA-M, LEA-M, and HBP-M) modified with octadecylamine, 12-aminolauric acid, N-lauryldiethanolamine, and hexadecyltributylphosphonium bromide, respectively, were used as layered silicates. X-ray diffraction and morphological studies using transmission electron microscopy revealed that the highly intercalated nanocomposites with the interlayer spacing more than 5.5 nm are formed for the PGM–CDCA/ODA-M, LEA-M, and HBP-M composites with inorganic content 3 wt%. When the inorganic content was increased from 3 to 5 wt%, the degree of intercalation of all the PGM–CDCA/organoclay composites was lowered. Dynamic viscoelastic measurement revealed that the organoclay nanocomposites have significantly higher storage modulus than the PGM–CDCA neat resin. The thermogravimetric analysis revealed that the HBP-M composite with inorganic content 5 wt% has the highest thermal decomposition temperature.

Mixed micelles of cationic 12-2-12 gemini with conventional surfactants: the head group and counterion effects

Mixed micelle formation by cationic 12-2-12 gemini with conventional single chain surfactants were studied with the help of conductivity, turbidity, and NMR measurements. The influence of steric contributions in the head group region and counterion effects on the mixed micelle formation have been explored. Favorable interactions are responsible for the mixed micelle formation of 12-2-12 with hexadecylpyridinium bromide (HPyBr), hexadecylpyridinium chloride (HPyCl), benzylhexadecyl dimethylammonium chloride (BHDACl), and benzyltetradecyl dimethylammonium chloride (BTDACl), whereas ideal mixing leads to the mixed micelles of 12-2-12 with hexadecyltrimethylammonium bromide (HTAB) and hexadecyltributylphosphonium bromide (HTBB). Specific interactions between the cationic head group of 12-2-12 and aromaticity of co-surfactant (CS) head groups were mainly attributed to the favorable micellization in the former case. Transmittance (turbidity) measurements identified the structure transitions of 12-2-12 with respect to the concentration, and which were in excellent agreement with those reported by Zana from cryo-TEM studies [Adv. Colloid Interface Sci. 97 (2002) 205]. The presence of small amount of cosurfactant drastically reduces the structure transitions of 12-2-12 and the reduction effect is maximum in the presence of HTAB and HPyCl. NMR measurements are in line with those of conductivity. They show that the intercalation of pyridinium and benzylic bulky head groups along with Cl − counterions induce maximum steric effects in the mixed micelles with 12-2-12 gemini in comparison to all other conventional surfactants.

Triphenyl- and tributyl-phosphonium head groups contributions in mixed cationic surfactants and anionic polyelectrolytes aggregates

Abstract Cationic micelle-anionic polyelectrolyte interactions of hexadecyltrimethyl ammonium bromide (HTAB), hexadecyltriphenylphosphonium bromide (HTPB), hexadecyltributylphosphonium bromide (HTBB), and their mixtures with carboxymethylcellulose (CMC) sodium salt, dextran (DX) sulfate sodium salt, polystyrene sulfonate (PSS) sodium salt, and polyacrylic acid (PAA) sodium salt were studied with the help of conductivity (κ), viscosity (η), turbidity (τ), and NMR studies. The results showed that among the phosphonium surfactants, HTPB interacts more strongly with polyelectrolytes than HTBB since the butyl chains of the latter screen the electropositive centre which has to interact with the active sites of anionic polyelectrolytes. This was explained on the basis of folding of butyl chains in the head group region of the micelle. 1 H NMR results further concluded that HTAB+HTPB produced compact mixed micelles, which interacted more strongly with polyelectrolytes in comparison to HTAB+HTBB mixed micelles.

Head-group-modification-controlled mixing behavior of binary cationic surfactants: conductometric, viscometric, and NMR studies

The mixed-micelle formation by hexadecyltrimethylammonium bromide (HTAB) with hexadecyltriphenylphosphonium bromide (HTPB) and hexadecyltributylphosphonium bromide (HTBB), and by hexadecylpyridinium bromide (HPyBr) with HTPB and HTBB has been studied with the help of conductivity, viscometry, and NMR studies. The conductivity studies showed close-to-ideal mixing in all cases with weak synergistic interactions. The relative viscosity is more sensitive than the conductivity and demonstrated that the micellization of HTAB, HPyBr, HTPB, and HTBB proceeded through the appearance of a minimum, whereas their mixtures showed a strong maximum in each case. NMR measurements suggested that bulky head groups of HTPB and HTBB induce significant steric hindrance in the mixed state upon mixing with HTAB and HPyBr. The appearance of the maximum shown by the relative viscosity in the mixed-micellization process is due to steric compulsions, which may also lead to some structural transitions.

A semi-molten mixture of hexadecyltributylphosphonium bromide and potassium fluoride in the synthesis of organofluorine compounds

A facile and effective reagent system comprising of a semi-molten mixture of hexadecyltributylphosphonium bromide and potassium fluoride has been developed and its scope has been investigated in nucleophilic fluoride exchange with various organohalides. This simple and convenient reagent system provides organofluorine compounds in high yields even with haloesters in which fluoride catalysed elimination is also feasible.

Adsorption of some quaternary onium salts on silica gel

The adsorption of quaternary onium salts such as hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, benzyltrimethylammonium chloride and tetrabutylammonium bromide from aqueous solution, and of tricaprylylmethylammonium chloride (Aliquat ® 336) and hexadecyltributyl phosphonium bromide from organic solution has been studied using silica as an adsorbent. The adsorption from the aqueous phase was found to be dependent on the pH of the medium, giving a type IV isotherm in acidic and alkaline solution. The adsorption from the aqueous phase in the medium pH region and from the organic phase appears to give a Langmuir-type isotherm. The equilibrium adsorption capacity and the adsorption rates in the aqueous phase were found to be higher than those observed for adsorption from the organic phase. The concentration-time profiles generated in an agitated slurry system indicate that in the case of aqueous phase adsorption in the middle pH range, external film diffusion controls the solute uptake initially and particle diffusion controls the solute uptake in the later stages, whereas for the organic phase adsorption, both film and surface diffusion seem to control the uptake.

Phase Transitions and Interfacial Rearrangements at the Surface Film of Adsorbed Hexadecyl-Tributylphosphonium Bromide Studied in a Capacitane-Potential-Time 3-Dimensional Space

Phase Transitions and Interfacial Rearrangements at the Surface Film of Adsorbed Hexadecyl-Tributylphosphonium Bromide Studied in a Capacitane-Potential-Time 3-Dimensional Space