Vinylbenzyltrimethylammonium Chloride Research Articles

Conformational transition of Poly (vinylbenzyltrimethylammonium chloride) (PVBTMAC) brush in the presence of Hofmeister anions

This study pertains to the conformational changes of Poly (vinylbenzyltrimethylammonium chloride) (PVBTMAC) brush onto SiO2-coated resonator; which was further incorporated by using quartz crystal microbalance with dissipation (QCM-D) in the presence of Hofmeister series of anions as a function of ionic strength. Gradual shrinkage of highly extended PVBTMAC followed by loose inhomogeneous layer was on account of change in frequency (∆f) and dissipation (ΔD) at low ionic strength. On the contrary, the increase in ionic strength collapses chains and dense homogenous layer is formed. The chaotropic anions comparativley bring drastic change in frequency unlike kosmotropic anions. This is because weakly hydrated chaotropic anions form strong ion pair with weakly hydrated trimethyl ammonium group on the PVBTMAC brush and as a result strong counter ion condensation was observed on polymer chain. Thus, the apparent mass associated with PVBTMAC chains increases that accounts for large change in ∆f.

Development of Functional Adsorbent From Textile Cotton Waste by Radiation Induced Grafting Process: Equilibrium and Kinetic Studies of Acid Dye Adsorption

An environment benign-aqueous solvent based-single step-radiation induced grafting process was used to graft Poly(vinylbenzyltrimethyl ammonium) chloride (PVBT) onto cellulosic cotton textile waste to transform it into a valuable cationic adsorbent (PVBT-g-Cellulose). The PVBT-g-Cellulose adsorbent was characterized by grafting yield determination, elemental analysis, scanning electron microscope (SEM), and fourier transformed infrared (FTIR) spectroscopy. The PVBT-g-Cellulose adsorbent, investigated for the removal of model dyes from manufactured solutions, exhibited equilibrium adsorption capacities of ∼540 mg/g, ∼474 mg/g, and ∼122 mg/g for acid blue 25(AB25), acid yellow 99(AY99), and acid blue 74(AB74), respectively. The degree of agreement between the adsorption isotherm models and experimental data followed the order: Langmuir-Freundlich>Redlich-Peterson>Langmuir>Freundlich. The kinetic adsorption data was found to be in close agreement with pseudo-second order kinetic model. The elution percentage of as high as ∼95% could be achieved for AB25 using a suitable eluent.

Synthesis of waterborne acrylic/clay nanocomposites by controlled surface initiation from macroinitiator modified montmorillonite

The nitroxide mediated controlled surface initiated polymerization of methyl methacrylate (MMA)/butyl acrylate (n-BA) was carried out with a macroinitiator modified montmorillonite. The macroinitiator was synthesized by the nitroxide mediated polymerization of vinylbenzyl trimethylammonium chloride (VBTMACl), methylmethacrylate (MMA) and styrene (S) at 90°C using BlocBuilder®. The macroinitiator was exchanged with the sodium cations of the montmorillonite, to yield surface modified reactive montmorillonite. The bulk polymerizations of BA/MMA from the clay surface produced controlled molecular weight polymers that were able to exfoliate the clay. This controlled polymer/clay nanocomposite was used as masterbatch and further dispersed in monomers and miniemulsified to perform miniemulsion polymerization of BA/MMA (90/10wt.%) at 30wt.% solids content at low emulsifier concentration. The adhesive properties of the nanocomposites prepared with the masterbatch were proved to be better than those prepared with an organically modified clay.

Capillary electrochromatography–mass spectrometry determination of melamine and related triazine by-products using poly(divinyl benzene-alkene-vinylbenzyl trimethylammonium chloride) monolithic stationary phases

In this study, a capillary electrochromatography (CEC) method coupled either with UV or mass spectrometric detection was developed for the detection of trace-amounts of melamine and its related by-products (ammeline, ammelide, and cyanuric acid). A series of poly(divinyl benzene-alkene-vinylbenzyl trimethylammonium chloride) monolithic columns, which were prepared by a simple in situ polymerization with divinyl benzene (DVB), vinylbenzyl trimethylammonium chloride (VBTA) and different types of alkene monomers such as 1-octene, 1-dodecene or 1-octadecene were used as separation columns, with the poly(DVB-1-dodecene-VBTA) monolith as the optimal chromatographic material because it provided a better separation. The detection limits of four melamine derivatives were in the ranged of 0.6–2.18mgL−1 by the optimal CEC–UV mode, and were reduced from 2.2 to 19.4μgL−1 by the optimal CEC–MS mode. Finally, the proposed CEC methods successfully determined melamine contaminations (0.1mgL−1 per analyte) in several dairy products as test samples with analyte recovery range of 69–85% (intra-day) and 68–75% (inter-day), and with peak area reproducibility range of 4.3–8.6% and 8.7–15.6% for intra-day and inter-day, respectively. This is the first report for CEC separation coupled with MS detection applied in trace melamine residue analyses with a faster separation and comparable or even better detection ability than previous GC–MS, CE–MS, as well as LC–MS methods.

Use of clay-anchored reactive modifier for the synthesis of poly (styrene-co-butyl acrylate)/clay nanocomposite via in situ AGET ATRP

Atom transfer radical polymerization using activators generated by electron transfer (AGET ATRP) was employed to synthesize well-defined poly (styrene-co-butyl acrylate)/clay nanocomposites. Dodecyltrimethylammonium bromide (DDTMAB) and Vinylbenzyltrimethylammonium chloride (VBTMAC) surfactants were used as clay modifier. The classical surfactant is used to expand the interlayer gallery of montmorillonite; however, double bond of reactive modifier participates in chain propagation process and forms clay-attached polymer chains. Subsequently synthesis of attached and free poly (styrene-co-butyl acrylate) chains and their composition was confirmed by Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy (1H NMR). Narrow distribution of nanocomposites molecular weight was confirmed by gel permeation chromatography (GPC). Partially exfoliated clay layers in the copolymer matrix were revealed by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Thermal properties of the nanocomposites were evaluated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Thermal decomposition of the nanocomposites was hindered in the presence of nanoclay. Dynamic mechanical thermal analysis (DMTA) results show that addition of nanoclay was also resulted in enhanced storage modulus (E′) in comparison with the neat copolymer. Lower glass transition temperature of nanocomposites was displayed by DSC.

Synthesis and characterization of EFFE-g-(VBTAC-co-HEMA) anion exchange membranes prepared by a 60Co radiation-induced graft copolymerization for redox-flow battery applications

Vinyl benzyl trimethyl ammonium chloride (VBTAC) was grafted onto poly(ethylene-co-tetrafluoroethylene) (ETFE) film by γ-ray using simultaneous irradiation graft copolymerization in the presence of 2-hydroxyl ethyl methacrylate (HEMA). The structure of the ETFE-g-(VBTAC-co-HEMA) anion membrane was confirmed by Fourier transform infrared spectroscopy and thermogravimetric analysis. The degree of grafting (DG) of the membrane increased with total irradiation dose and VBTAC monomer concentration. The highest DG of an ETFE-g-(VBTAC-co-HEMA) membrane was 92%, which was synthesized by the treating of an ETFE film with a 0.8 M solution of VBTAC monomer in the presence of 50 kGy irradiation. Different properties of the anion membrane, such as water uptake and ion exchange capacity, increased as DG increased. The permeability and vanadium redox-flow battery performance were measured for a membrane with a DG of 92%. The average voltage efficiency, coulombic efficiency, and energy efficiency were 0.79, 0.88, and 0.70, respectively, all of which remained stable as the number of cycles increased. Open image in new window

Polymeric ionic liquids (PILs): Effect of anion variation on their CO 2 sorption

A series of polymeric ionic liquids (PILs) based on poly(diallyldimethylammonium chloride), P[DADMA][Cl] as a precursor was investigated by varying anions categorized into carboxylates, sulphonates and inorganic type. For the exchange of chloride from P[DADMA][Cl] by another anion, silver salt of the corresponding anion was preferred. Obtained PILs were investigated for physical properties which are anticipated to affect gas sorption. PILs possessing carboxylate (especially acetate) anion exhibited attractive CO 2 sorption capacity as well as sorption selectivity over H 2 and N 2, in comparison to other two categories. PIL with acetate anion, P[DADMA][Ac] possessed appreciable CO 2 sorption coupled with high selectivity ( S CO 2 / S N 2 = 114.3 ) . This crucial finding from this series of PILs was further substantiated by making PIL based on poly(vinylbenzyltrimethylammonium chloride), P[VBTMA][Cl] as a precursor.

Temperature-Swing Adsorption of Proteins in Water Using Cationic Copolymer-Grafted Silica Particles

We have prepared silica particles grafted with poly(N-isopropylacrylamide) (PNIPA) copolymers as adsorbent for the temperature-swing adsorption of bovine serum albumin (BSA) in water, where vinylbenzyl trimethylammonium chloride (VBTA), 2-(dimethylamino)ethyl methacrylate (DMAEMA), or N,N-dimethylacrylamide (DMAA) was employed as a comonomer. The surface potentials of PNIPA-grafted and P(NIPA-co-DMAA)-grafted silica particles in water at 298 and 313 K were negative, while those of P(NIPA-co-VBTA)-grafted silica particle were positive, because VBTA is a quaternary ammonium salt and positively charged in aqueous solutions. As for the P(NIPA-co-DMAEMA)-grafted silica particle, the surface potential changed from positive to near zero with increasing temperature from 298 K to 313 K. This may be because the coil-to-globule transition of grafted copolymers leads to the dehydration and deprotonation of DMAEMA group, which is a tertiary amine and can be positively charged only in the aqueous phase. Although PNIPA-grafted and P(NIPA-co-DMAA)-grafted silica particles failed to adsorb BSA, P(NIPA-co-VBTA)-grafted and P(NIPA-co-DMAEMA)-grafted silica particles adsorbed BSA, indicating that BSA is adsorbed by the electrostatic attraction between the negatively charged BSA and the positively charged copolymers on the silica surface. Moreover, P(NIPA-co-VBTA)-grafted and P(NIPA-co-DMAEMA)-grafted silica particles repeatedly adsorbed BSA at 298 K and desorbed some of the preadsorbed BSA at 313 K via the temperature-swing operation. This BSA desorption may result from the decrease in the number of the positively charged groups accessible to BSA due to the coil-to-globule transition of the grafted copolymers with increasing temperature.

電子線グラフト重合法による製塩用新規イオン交換膜の開発 （第2報）ナイロンフィルムへのビニルベンジルトリメチルアンモニウムクロライドおよびスチレンスルホン酸ナトリウムのグラフト重合

電子線グラフト重合法による製塩用新規イオン交換膜の開発 （第2報）ナイロンフィルムへのビニルベンジルトリメチルアンモニウムクロライドおよびスチレンスルホン酸ナトリウムのグラフト重合

Exploring the Heteroatom Effect on Polyelectrolyte Multilayer Assembly: The Neglected Polyoniums

Different positive polyelectrolytes having the same charge density, molecular weight, and molecular weight distribution were employed for polyelectrolyte multilayer (PEMU) assembly. The polycations differed only in the heteroatom on which the positive charge resided: poly(vinyl benzyl trimethyl ammonium) chloride, poly(vinyl benzyl trimethyl phosphonium) chloride, and poly(vinyl benzyl dimethyl sulfonium) chloride. While the ammonium repeat unit has been employed on numerous occasions for PEMU assembly, the phosphonium and sulfonium units are relatively neglected. The polyanions, poly(styrene sulfonate), PSS, or poly(acrylic acid), PAA, were typical pH-independent or pH-dependent polymers, respectively. All three polyoniums were quite similar in showing linear layer-by-layer buildup with PSS and exponential growth with PAA, under the conditions employed. Hydration and wettability were also similar between polyoniums.

One-Pot Pathway: Fabricating Ordered Hollow Silica Spheres Using Sodium Silicate as the Precursor

The preparation of hollow silica spheres via the sodium silicate route presents many advantages such as a low-cost silica source, and an environmentally friendly reaction system. Unfortunately, it is extremely hard to prepare the well-defined hollow silica spheres by using sodium silicate as the silica source owing to its rapid, disordered precipitation under the acid catalysis. As a result, we, in this paper, report a facile, economic, one-pot pathway for preparation of the ordered hollow silica spheres by employing a sodium silicate precursor. In this approach, the cationic polystyrene (CPS) templates can be first prepared via emulsifier-free emulsion polymerization by using the cationic monomer vinylbenzyltrimethylammonium chloride, then, the silica shells were attached on the surfaces of CPS particles via electrostatic interaction, finally CPS particles were in situ dissolved and removed by adding toluene to create ordered hollow silica spheres. Some modern techniques and instruments, including the transmission electron microscope, scanning electron microscopy, infrared spectroscopy, thermogravimetric analysis, and Brunauer-Emmett-Teller theory were employed to monitor and characterize the resulting hollow silica spheres.

Poly(vinylidene fluoride) based anion conductive ionomer as a catalyst binder for application in anion exchange membrane fuel cell

An anion conductive polymeric ionomer incorporated into the electrodes of an anion exchange membrane fuel cell (AEMFC) can help to enhance anion transport in the catalyst layer of electrode, and thus improve the catalyst efficiency and performance of AEMFC. In this work, we report the synthesis and properties of a new type of anion conductive ionomer, which is synthesized by grafting of poly(vinylidene fluoride), or PVDF with poly(vinylbenzyltrimethylammonium chloride) via atom transfer radical polymerization. The ionomer obtained shows improved hydrophilicity relative to pristine PVDF, and exhibits an ion exchange capacity of 1.59mmolg−1. When used in a direct hydrazine hydrate fuel cell (DHFC) as a catalyst binder, the synthesized ionomer imparts the DHFC a significantly improved power density, which is 5–10 fold as much as that of the cells without using such ionomer. The method developed here for anion exchange ionomer synthesis is facile, green and does not involve the use of carcinogenic chemicals such as chloromethylmethylether and trimethylamine, which are often used for conventional anion exchange membrane or ionomer synthesis.

Preparation of tailor-made polystyrene nanocomposite with mixed clay-anchored and free chains via atom transfer radical polymerization

Tailor-made polystyrene nanocomposite with mixed free and clay-attached polystyrene chains was synthesized using atom transfer radical polymerization. Vinylbenzyl trimethylammonium chloride having a double bond, which could be incorporated into polystyrene chains by a grafting through process, was used as a nanoclay modifier. Conversion and molecular weight evaluation was carried out using gas chromatography and gel permeation chromatography, respectively. The thermogravimetric analysis results confirmed the elevated thermal stability of the nanocomposites in comparison with the neat polystyrene sample. Additionally, the Tg increases by clay loading was confirmed by differential scanning calorimetry (DSC). The difference in the degradation temperature of CBr bond in attached and free polystyrene chains was well revealed in DSC thermograms. Finally, a lower clay loading resulted in an exfoliated structure as proved by X-ray diffraction and transmission electron microscopy results. © 2010 American Institute of Chemical Engineers AIChE J, 2011

Investigation of temperature-swing adsorption of aromatic compounds in water using polyampholyte gels with hydrophilic nonionic groups

The adsorption and desorption behaviors of bisphenol-A in water have been studied using the temperature-responsive polyampholyte gels composed of sodium styrene sulfate (SSS), vinylbenzyl trimethylammonium chloride (VBTA), and N,N′-dimethylacrylamide (DMAA). The resultant behaviors of the SSS-VBTA-DMAA gels of three different monomer compositions are compared with those of the SSS-VBTA gel that can adsorb bisphenol-A at room temperature and desorb the pre-adsorbed bisphenol-A at higher temperature as in our previous report (Morisada et al., Adsorption 2008, 14, 621), to elucidate the effect of DMAA on the adsorption property of the polyampholyte gel. The adsorption isotherms, which were described by Henry's law, indicated that the adsorption amounts of bisphenol-A onto the SSS-VBTA-DMAA gels at 298 K are much larger than those at 353 K. At 298 K, the Henry's adsorption constant for the SSS-VBTA-DMAA gel with the lowest mole fraction of DMAA was larger than that for the SSS-VBTA gel, whereas a further increase in the DMAA mole fraction resulted in a decrease in the adsorption constant. Moreover, the temperature-swing adsorption experiments demonstrated that the SSS-VBTA-DMAA gel can repeatedly adsorb bisphenol-A at 298 K and desorb some of the pre-adsorbed bisphenol-A at 353 K, where the desorption amount of bisphenol-A is larger than that from the SSS-VBTA gel. The results obtained here show that the addition of DMAA to the SSS-VBTA gel slightly improves the performance of the gel as a temperature-responsive adsorbent. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Three dimensionally flocculated proangiogenic microgels for neovascularization

Microparticles encapsulating regenerative medicines have been used in tissue engineering because of their several advantages, including non-invasive drug delivery and controllable drug release rates. However, microparticles implanted in tissue defects are readily displaced by external mechanical forces, decreasing their regenerative efficacy. We hypothesized that a drug-encapsulated colloidal gel formed through colloidal attraction between microparticles would resist displacement at an implant site, and subsequently improve therapeutic efficacy. This hypothesis was examined using a colloidal gel formed from the mixing of negatively charged microgels composed of poly(ethylene glycol) (PEG) and poly(sodium acrylate), and positively charged microgels composed of PEG and poly(vinyl benzyl trimethyl ammonium chloride). The structural strength of the colloidal gel could be tuned with the zeta potential and volumetric ratios of the oppositely charged microgels. Furthermore, the implantation of the colloidal gel, encapsulating vascular endothelial growth factor, significantly increased the vascular density while limiting host inflammation, as compared with the implantation of unary microgel suspensions. This study demonstrates an enhancement in the efficacy of microparticle drug delivery systems by tuning rheological properties of suspensions, which should be useful for the design of a wide array of particulate systems for both tissue engineering and drug delivery.

Photoinduced cografting of vinyl benzyl trimethylammonium chloride and 2‐hydroxyethyl methacrylate onto nylon nonwoven fabric for preparing an anion‐exchange sorbent: Optimum cografting conditions and characterization

AbstractVinyl benzyl trimethylammonium chloride (VBTAC) and 2‐hydroxyethyl methacrylate (HEMA) were cografted onto nylon fiber by photoirradiation‐induced graft polymerization with benzophenone (BP) as the photoinitiator and methanol (MeOH) as the solvent. The cografted VBTAC afforded an anion‐exchange functionality to the nylon‐g‐HEMA–VBTAC fabric without any further modification. The concentration of each and the ratio of the HEMA and VBTAC monomers in solution were the most important factors determining the degree of grafting and anion‐exchange capacity (AEC) of nylon‐g‐HEMA–VBTAC. With regard to the AEC of the grafted fabric, the optimal HEMA/VBTAC ratio was 10 : 7 (v/w), which gave a molar fraction of VBTAC of 0.286. The photoirradiation time, temperature of the reaction, and concentrations of BP and MeOH were optimized for the cografting of VBTAC and HEMA onto the nylon fabric. The molar ratio of VBTAC units in the grafted polymer was dependent on the photoirradiation time but not on the other parameters. The results showed that the AEC of nylon‐g‐HEMA–VBTAC was governed directly by its VBTAC density rather than by its degree of grafting. The grafted fabric was characterized in terms of its surface area, porosity, and surface charge density by Fourier transform infrared, 13C‐NMR, and scanning electron microscopy studies, and the regeneration efficiency was estimated. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

The role of cationic monomers in emulsion polymerization

[2-(methacryloyloxy)ethyl] trimethylammonium chloride (MATMAC), and vinylbenzyl trimethyl ammonium chloride (VBTMAC) were chosen to be used as ionic comonomers in the emulsion polymerization of styrene. The cationic nature of the two comonomers is the same (quaternary ammonium salts), however the styrene derivate (VBTMAC) is more hydrophobic than the methacrylic one (MATMAC). With the more hydrophobic cationic comonomer (VBTMAC) higher conversions were obtained due to the in situ creation of an amphiphilic copolymer with styrene and faster rates of polymerization were observed by increasing the cationic comonomer concentration. The same behavior was observed with the more hydrophilic cationic comonomer (MATMAC) at concentrations up to 0.012 M. At higher concentrations the ionic strength controls the colloidal stability of the system and coagulation occurs.

Formation of crystalline colloidal arrays by anionic and cationic polystyrene particles

Cross-linked polystyrene microspheres bearing positive and negative charges have been prepared by surfactant-free emulsion polymerization by the use of various amounts of vinylbenzyltrimethylammonium chloride and sodium styrenesulfonate as comonomers, respectively. Increasing the amount of the ionic comonomers tends to decrease the particle size due to better surface stabilization, but a high concentration of an ionic comonomer leads to a competitive mechanism that increases the polydispersity of the particle size. The amount of cationic and anionic comonomers leads to differences in size, shape and uniformity of the particles. The cationic particles can self-assemble into crystalline colloidal arrays with intense visible light diffraction just like the anionic ones. It is particularly interesting to observe that good packing can be obtained even for particles not quite uniform in size. To better understand the packing behavior, the properties and stability of the colloidal crystals have been studied as a function of the particle concentration and ionic strength of the media. The presence of charges helps in the formation of periodic structure over a wide range of particle concentrations at low ionic strength.

Analyses of sulfonamide antibiotics by CEC using poly(divinylbenzene‐1‐octadecene‐vinylbenzyl trimethyl ammonium chloride) monolithic columns

In this study, a series of novel polymeric monolithic columns prepared by single-step in situ copolymerization of 1-octadecene (OD), divinylbenzene (DVB) and/or styrene (S), were developed as separation columns for the sulfonamide analyses. On the CEC method, the composition of monomer mixtures (i.e. the ratio of S versus OD), content of charge-bearing monomer (vinylbenzyl trimethylammonium chloride) and volume fraction ratio of ACN in the mobile phase, was found to be the predominant influences for sulfonamide separation. Furthermore, an online sample concentration step, field-amplified sample injection, was used to enhance the detection sensitivity of sulfonamides. Sample matrix's pH had a significant effect on the sulfonamide sensitivity. For the eight sulfonamides, the proposed poly(DVB-OD) monolithic stationary phase coupled with field-amplified sample injection step could achieve a reproducible baseline separation within 15 min and LODs in the range of 8.1-28.2 microg/L.

Temperature-swing adsorption of proteins in water using N-isopropylacrylamide copolymer gel particles

The adsorption and desorption behaviors of bovine serum albumin (BSA) in water for temperature-responsive polymer gel particles have been investigated by the temperature-swing operation between 298 and 313K, where the cationic N-isopropylacrylamide (NIPA) gels copolymerized with vinylbenzyl trimethylammonium chloride (VBTA) or 2-(dimethylamino)ethyl methacrylate (DMAEMA) were used. The NIPA-VBTA and the NIPA-DMAEMA copolymer gels adsorbed BSA while the NIPA homopolymer gel hardly adsorbed BSA, indicating that the copolymer gels adsorb BSA through the electrostatic attraction between the positively charged groups in the gels and the negatively charged BSA. The adsorption amounts for the NIPA-DMAEMA gels were smaller than those for the NIPA-VBTA gels. This may be because almost every VBTA group, which is a quaternary ammonium salt, can be positively charged in water, while only some of the tertiary amine DMAEMA groups are protonated in water. Moreover, it was found that both the copolymer gels with a large mesh size of the polymer network repeatedly adsorbed BSA at 298K and desorbed some of pre-adsorbed BSA at 313K by the temperature-swing operation. This BSA desorption may result from the decrease of the number of the positively charged groups accessible to BSA due to the shrinking of the constituent polymer chains.