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The increased micro-capacitance of a poly (vinylidene fluoride) (PVDF) matrix can effectively improve the piezoelectric properties of the composite material. This work used chemically modified carbon nanotubes (CNTs) as the main reinforcement material. Atom transfer radical polymerization (ATRP) was used to graft polyionic liquids (PILs) with different hydrophilic anions to the CNTs' surfaces. Solution casting and compressive melt molding were used to prepare the PVDF-composite piezoelectric films. Micro-capacitance formed by the PIL grafted CNTs dispersed well in the PVDF matrix, and their effects on the crystalline form and piezoelectric properties were studied. The hydrophobic hexafluorophosphate anion (-PF6-) can significantly improve the CNTs dispersion and enhance the micro-capacitance formation in the PVDF matrix. During solution crystallization, the synergistic effect of CNTs and PIL on the PVDF and the solvent effect made the content of β phase of PVDF/CNTs@PIL-PF6 film reach 80.2%, resulting in a high dielectric constant of 188 and a piezoelectric coefficient of 36. In the process of melt crystallization, due to shear stretching and extrusion, the CNTs@PIL-PF6 had an obvious nucleation effect on the polar crystalline phase of PVDF, with a β phase content up to 99.3%, leading to the higher dielectric constant of 530 and the piezoelectric coefficient of 31. The current discovery provides a development direction for smart piezoelectric polymer matrix composites, which have great potential in preparing piezoelectric energy storage materials. [ABSTRACT FROM AUTHOR]

In this research, a poly (ionic liquid) functionalised silica-coated magnetic nanoparticles were synthesised for the first time and utilised as a novel adsorbent for the simultaneous extraction of six phthalic acid esters from polyethylene terephthalate bottled drinking water samples. The adsorbent was prepared by grafting poly (1-benzyl-3-vinyl-1 H-imidazol-3-ium chloride) onto silica-coated Fe3O4nanoparticles via Cu(0)-mediated reversible-deactivation radical polymerisation method. Various techniques were used to characterise the synthesised nanomaterials. A qualitative analysis was performed using ultra-performance liquid chromatography triple–quadrupole tandem mass spectrometry. Response surface methodology based on central composite design was used to optimise the extraction procedure and the optimised condition for each factor was; pH of3.9, 22 mg of adsorbent, 3.5 min extraction time, 3 min desorption time, 340 µL of elution solvent (methanol).The results of the validation of the method indicated its acceptable accuracy (88.6-100.1%), good linearity (r > 0.995), satisfactory repeatabilities (RSDs ≤ 6% for intra- and inter–day precisions) and high enrichment factors (535–572). The limits of detection and limits of quantification of the proposed method achieved were 1.1-4.6 ngL–1and 3.6-15.3 ngL–1, respectively. In this study, six common PAEs, including dimethyl phthalate, diethyl phthalate, dibutyl phthalate, benzyl butyl phthalate, bis (2-ethylhexyl) phthalate, and di-n–octyl phthalate, were found in PET bottled water within the range of 0.21-0.94 μgL–1, under different storage conditions. Nevertheless, only a negligible risk is caused by the PAEs in PET bottled water for consumers following the recommendations, such as storing at a common place (25°C), in a short period away from the sun. [ABSTRACT FROM AUTHOR]

In this work, we reported a novel emulsion copolymerization of vinyl chloride monomer (VCM) with amphipathic monomer poly (ethylene glycol) methyl ether methacrylate (PEGMA) by using sodium dodecyl sulfate (SDS) as emulsifier and K2S2O8/NaHSO3 as redox initiator. Owing to the multifunctionality of PEGMA that can serve as co-monomer and 'emulsifier', the emulsion copolymerization is achieved successfully and the interesting results demonstrate quite different features such as:(1) the stable P[(VC)-co-(PEGMA)] latex is obtained only when the mass ratio of PEGMA > 10% (to total monomer mass), (2) a small amount of ionic emulsifier SDS is required to achieve a stable latex, and (3) the mechanism of the micellar formation is different from the typical emulsion polymerization. Unexpectedly, the obtained copolymer formed high content of gel fraction which is mainly caused by the chain transfer reaction of the PVC growth chain radical to the hydrogen atom of the methylene from alkoxy (-OCH2CH2-) of the PEGMA oligomer chain. However, it could be inhibited effectively by the addition of chain transfer agent 2-mercaptoethanol (2-MCE). Subsequently, the properties of as-obtained P[(VC)-co-(PEGMA)] copolymer are evaluated carefully and it exhibited unique features such as self-plasticization, lower Tg (decreased from 83.1 to 59.6 °C), higher heat resistance (increased from 270 to 290 °C), hydrophilic, and high transparent in comparison to pure PVC. These outstanding features of the P[(VC)-co-(PEGMA)] copolymer offered a potential route for the functional modifications of PVC and broadened its further use. [ABSTRACT FROM AUTHOR]

Coffee is one of the most consumed beverages in the world. Coffee provides to the consumer special sensorial characteristics, can help to prevent diseases, improves physical performance and increases focus. In contrast, coffee consumption supplies a significant source of substances with carcinogenic and genotoxic potential such as furan, hydroxymethylfurfural (HMF), furfural (F), and acrylamide (AA). The present review addresses the issues around the presence of such toxic substances formed in Maillard reaction (MR) during thermal treatments in food processing, from chemical and, toxicological perspectives, occurrences in coffee and other foods processed by heating. In addition, current strategies advantages and disadvantages are presented along with application of molecular imprinting technology (MIT) and poly (ionic liquid) s (PIL) as an alternative to reduce the furan, HMF, F and AA content in coffee and other foods. [ABSTRACT FROM AUTHOR]

Two new poly(ionic liquid)s (PILs) were synthesized, characterized, and applied in breaking waterin-oil (W/O) emulsions. For that, tetraethylene glycol (TG) was treated with thionyl chloride, obtaining dialkyl chloride (TC). TC was reacted with diamines 1,5-diaminopentane (AP) and 1,11- diaminoundecane (AU), forming the corresponding polyamines, TC-AP and TC-AU. Following this, TC-AP and TC-AU were quaternized with acetic acid (AA), producing poly(ionic liquid)s (PILs), TCAPPIL, and TCAU-PIL, respectively. Chemical structures, thermal stability, surface activity, aggregation size, and zeta potential measurements were investigated using several techniques. In addition, their performance in breaking (PB) W/O emulsions in different ratios was investigated. TCAP-PIL and TCAU-PIL exhibited high PB at all ratios, while their performance improved as the crude oil ratio decreased. Moreover, TCAU-PIL showed higher PB than TCAP-PIL, which may be linked to the increased hydrophobicity of TCAU-PIL due to increased methylene units in the diamine chain compared to TCAP-PIL. [ABSTRACT FROM AUTHOR]

How to simultaneously improve the ionic conductivity and mechanical properties is a key problem facing currently used anion-exchange membranes (AEMs). Here, novel AEMs were prepared using quaternized bacterial cellulose (QBC) as a dual-functional substrate and then filled with a polymeric ionic liquid (poly(vinylbenzyl) trimethylammonium chloride, PVD) with high ion-exchange capacity through in situ polymerization and crosslinking. The dense quaternary ammonium groups grafted on the surface of BC nanofibers greatly increased the ionic conductivity, while the special three-dimensional network structure of BC significantly enhanced the tensile strength and chemical stability of the obtained PVD filled quaternized BC (QBC/PVD) membranes. The ionic conductivity of QBC/PVD membrane reached as high as 111 mS cm−1 at 80°C, which was 109% higher than that of the pure BC/PVD membrane (only 53 mS cm−1). Moreover, the QBC/PVD membrane exhibited extremely high dry strength of 72.3 MPa and satisfactory wet strength and flexibility, this membrane can hang a container containing 500 g of water when at fully hydrated state. The alkaline direct methanol fuel cell equipped with QBC/PVD output a peak power density of 64 mW cm−2, showing its great application potential as an AEM. [ABSTRACT FROM AUTHOR]

A novel quasi-solid-state polymer electrolyte was prepared using poly(vinyl alcohol)-polypyrrole, potassium iodide, iodine, and ethylene carbonate mixed with two types of ionic liquids, 1-methyl-3-propylimidazolium iodide (MPII) and 1-ethyl-3-methylimidazolium iodide (EMII). The prepared polymer electrolyte was structurally characterized by FTIR spectroscopy. The lowest degree of crystallinity and activation energy were found in the MPII-incorporated polymer electrolytes. Higher values of dislocation density and microstrain are obtained for ionic liquid-incorporated polymer electrolytes. The lowest value of series resistance was observed in MPII-based polymer electrolyte and thereby the conduction was increased. The average roughness of the MPII-based polymer electrolyte at 17.901 nm was strongly dependent on the influence of the MPII content. The dye-sensitized solar cells (DSSC) built with MPII-based polymer electrolytes have achieved the highest photo-conversion efficiency of 4.51% under 100mWcm−2 illumination. [ABSTRACT FROM AUTHOR]

The aggregation behavior of imidazolium-based long-chain ionic liquid 1-tetradecyl-3-methylimidazolium bromide [C14mim][Br] has been investigated in the absence and presence of (1, 2, and 5) mM tetrabutylammonium bromide (C4H9)4NBr at three temperatures (298.15, 308.15, and 318.15) K. The critical micelle concentration (CMC), surface parameters such as maximum surface excess concentration ( Γ max ), the minimum area surfactant monomer at the air/water interface ( A min ), surface tension at CMC ( γ cmc ) and surface pressure ( ᴨ cmc ) are determined by employing conductivity and surface tension measurements. Various thermodynamic parameters of micellization such as standard free energy of micellization ( Δ G m 0 ), standard enthalpy of micellization ( Δ H m 0 ), and standard entropy of micellization ( Δ S m 0 ) are calculated by utilizing the temperature dependence of CMC observed using conductivity study. Other thermodynamic parameters such as free energy of adsorption (Δ G a d 0 ) and surface free energy ( G min s ) are also evaluated. Refractive index measurements and UV–vis spectroscopic studies have been utilized to confirm the values of CMC obtained via conductivity and surface tension measurements. FTIR spectroscopic studies signify the various interactions prevailing in the system constituting long-chain ionic liquid and electrolyte. [ABSTRACT FROM AUTHOR]

Polymer microspheres have been widely used as a stationary phase in liquid chromatography. We characterized the properties of the novel polyionic liquid microspheres prepared and explored their application as a stationary phase in liquid chromatography. Cytosine, uracil, benzene, benzene homologs and alkaloids were successfully separated by liquid chromatography with the polymer microspheres as packing materials in the chromatographic column. [ABSTRACT FROM AUTHOR]

Two kinds of thermotropic liquid crystalline polyesters (TLCP) with different chemical structures were used as flow modifiers during the melt spinning of poly (ether ether ketone). One of TLCPs, named PAT-S, was a kind of aromatic polyester synthesized from 4-acetoxybenzoicacid and 6-hydroxy-naphthoic acid, and the other one named, PEEKAR, was a block copolymer based on poly (ether ether ketene) (PEEK) oligomers and PAT-S oligomers. The effects of the chemical structures of the prepared TLCPs on the rheological behavior of the TLCP/PEEK blends were measured by rheological measurements, and then the structure and properties of the TLCP/PEEK in-situ blend fibers were studied by a series of methods, including differential scanning calorimetry (DSC), wide angle X-ray diffraction (WRXD), optical microscopy (OM), scanning electron microscopy (SEM), orientation degree tests, mechanical properties tests, etc. The results showed that the melt viscosity of PEEK could be effectively reduced by nearly 20% by adding a small amount of PEEKAR or PAT-S with the viscosity reducing effect of PEEKAR on PEEK being greater than that of PAT-S; this was mainly caused by the better compatibility between PEEK and PEEKAR because of the similar segment structures. The crystallinity of the PEEK fibers increased by nearly 50% with addition of both TLCPs, indicating that both the PEEKAR and PAT-S could serve as nucleating agent as well. The results from the morphology analysis clearly proved that PEEKAR had a better compatibility with the PEEK resin compared with PAT-S. The tensile strength of the PEEK fibers could be improved to some extent by adding PEEKAR, while it was obviously reduced after adding PAT-S. [ABSTRACT FROM AUTHOR]

We synthesise a novel poly(ionic liquid) (PIL) and develop a procedure that allows the phase transfer of graphene oxides (GO) from water to organic solvent, retaining graphene oxide liquid crystal (GOLC) phase in various organic solvents, especially non-polar organic solvents. PIL ([PEP-MIM]DBS) is exploited in this procedure as a noncovalent functional material that is capable of transporting GO from aqueous to non-polar organic phase. PILs can decorate GO noncovalently and keep GO nano-sheets exfoliated in solid-state PILs/GO hybrids, which can well redisperse in organic solvents without any agglomeration. This expands the number of known solvents which can support GOLC phase to dimethyl formamide, dimethyl sulfoxide, acetonitrile, tetrahydrofuran, and a number of other non-polar organic solvents, many of which were not known to afford GOLC phase prior to this report, such as dichloromethane, tetrachloromethane, dichloroethane and tetrachloroethane. [ABSTRACT FROM AUTHOR]

A facile route for grafting poly(ionic liquid)s (PILs) on to the surface of multi-walled carbon nanotubes (MWNTs) was demonstrated via Diels-Alder (DA) “click” reaction. Firstly, block copolymers of poly(chloromethylstyrene-alt-maleic anhydride) (PCMA) were prepared by the reversible addition-fragmentation chain transfer (RAFT) polymerization. The anhydride units in the copolymer were functionalized with furfuryl amine and then the chloromethyl groups were subsequently tailored with 1-methylimidazole, which afforded imidazolium-based PILs bearing pendent furan moieties. The PILs chains were covalently anchored to the surface of MWNTs, affording PILs/MWNTs by the DA reaction in water under ultrasound assistance. The obtained hybrid materials were characterized by TGA, FT-IR, and TEM analysis. The PILs/MWNTs could be well dispersed in water and organic solvents for several months. [ABSTRACT FROM AUTHOR]

Polymeric ionic liquids or poly(ionic liquid)s combine unique properties of ionic liquids with macromolecular characteristics. One of the spotlights of review was to identify potential areas of poly(ionic liquid)s. Due to unique combination of polymer and counterions, poly(ionic liquid)s possess tunable properties to be employed in range of advanced applications. Poly(ionic liquid)s composites have claimed relevance in energy storage/production and catalysis. In biosensors, poly(ionic liquid)s were employed to fabricate enzyme electrodes. Moreover, stimuli-responsive copolymers were used to form multi-responsive poly(ionic liquid)s. Separation membranes have been reported for gas separation/storage/transport. A significant use of poly(ionic liquid)s was found as solid-state electrolyte. In fuel cell, poly(ionic liquid)s-based electrolyte membranes were employed. [ABSTRACT FROM PUBLISHER]

Retaining reflection color developed from the photonic crystals has been our main interest. Persistent reflecting color from polymer photonic crystals using non-volatile solvents has been huddled by permeation of large molecular weight solvents. Some ionic liquids can permeate in between polymer photonic crystal layers. Polystyrene-b-poly-2-vinylpyridine (PS-b-P2VP) was used to obtain photonic crystals. The molecular weight of PS-b-P2VP and the hydrophobicity of the ionic liquids were altered to attain persistent color. Imidazolium and 1-ethyl-3-methylimidazolium were used as cations of ionic liquids where the anion was bis(trifluoromethanesulfonyl)imide. The photonic crystals made with block copolymers of 84k–69k and 57k–57k molecular weights showed the persistent distinct colors by swelling with the ionic liquids. [ABSTRACT FROM PUBLISHER]