Propyl Trimethyl Ammonium Chloride Research Articles

Synthesis and evaluation of a novel ternary quaternary ammonium salts-fluorescent template copolymer: Integrating flocculation, sterilization, and monitoring functions

Developing flocculants with sterilization and monitoring functions is of practical significance for optimizing water treatment agents. In this research, a fluorescent monomer, EtFl, with double bonds was synthesized and copolymerized with acrylamide (AM) and 3-(methacryloyloxy)propyltrimethylammonium chloride (MAPTAC) using a linear anionic template agent. This synthesis successfully produced a multifunctional template copolymer, TP(AM-MAP-EtFl), with flocculation, sterilization and monitoring capabilities. The fluorescence intensity of TP(AM-MAP-EtFl) was measured using a fluorescence spectrophotometer, demonstrating strong performance even with an EtFl monomer mass fraction as low as 0.5 wt‰, resulting in a fluorescence intensity value of 1000 a.u., suitable for analytical detection. In flocculation experiments with simulated wastewater containing E. coli, the introduction of the fluorescent monomer did not affect E. coli flocculation. When flocculation conditions are optimized, the OD600 readings of the clear liquid remaining after treating with TP(AM-MAP-EtFl#0.5) and TP(AM-MAP-EtFl#5) are 0.0297 and 0.0457, respectively, illustrating superior sterilization effects. Interestingly, SEM and 3D-EEM results confirmed TP(AM-MAP-EtFl)’s bactericidal effect on E. coli, with the introduction of the fluorescent monomer not affecting the sterilization capability of quaternary ammonium. This work integrates flocculation, sterilization and fluorescence properties to provide sterilization-type flocculants with monitoring capabilities, enabling accurate calculation of polymer concentration by detecting solution fluorescence intensity, thereby offering potential for online detection and automatic control of water treatment systems, demonstrating good applicability.

Temperature-Adaptative Self-Oscillating Gels: Toward Autonomous Biomimetic Soft Actuators with Broad Operating Temperature Region.

Self-oscillating gel systems exhibiting an expanded operating temperature and accompanying functional adaptability are showcased. The developed system contains nonthermoresponsive main-monomers, such as N,N-dimethylacrylamide (DMAAm) or 2-acrylamido-2-methylpropane sulfonic acid (AMPS) or acrylamide (AAm) or 3-(methacryloylamino)propyl trimethylammonium chloride (MAPTAC). The gels volumetrically self-oscillate within the range of the conventional (20.0°C) and extended (27.0 and 36.5°C) temperatures. Moreover, the gels successfully adapt to the environmental changes; they beat faster and smaller as the temperature increases. The period and amplitude are also controlled by tuning the amount of main-monomers and N-(3-aminopropyl) acrylamide. Furthermore, the record amplitude in the bulk gel system consisting of polymer strand and cross-linker at 36.5°C is achieved (≈10.8%). The study shows new self-oscillation systems composed of unprecedented combinations of materials, giving the community a robust material-based insight for developing more life-like autonomous biomimetic soft robots with various operating temperatures and beyond.

Investigation of Filtration and Shale Inhibition Characteristics of Chitosan-N-(2-hydroxyl)-propyl trimethylammonium Chloride as Drilling Fluid Additives.

Hydrated shale formations often lead to severe drilling problems and may lead to wellbore instability. These instabilities can result in issues such as bit balling, borehole collapse, formation damage, stuck pipe, and low drilling rates. Keeping these fundamental issues with drilling in shale formation in mind, this study is aimed at designing a water-based drilling fluid system for effective shale inhibition, ensuring enhanced wellbore stability and drilling efficiency. The designed mud system comprises a typical base fluid along with newly synthesized chitosan derivative chitosan-N-(2-hydroxyl)-propyl trimethylammonium chloride (HACC) as an additive. This additive was found to be soluble in water and conducive for shale inhibition. The derived product was characterized by field emission scanning electron microscopy, thermogravimetric analysis, and Fourier-transform infrared spectroscopy (FTIR). Various drilling fluid tests, including filtration and rheological experiments, were conducted to evaluate its proficiency as a drilling mud additive. The results showed improvement in rheological and filtration properties after hot rolling at 100 °C in comparison to a conventional shale inhibitor, polyethylenimine. As we increase the concentration of synthesized chitosan derivative from 0.3 to 1.5 w/v%, the filtration loss is reduced from 40% to 65% as compared to the base fluids. Shale recovery tests were also conducted using shale samples from an Indian field to assess its viability for field application. The addition of 0.3 to 1.5 w/v% chitosan derivative resulted in high shale recovery above 88% to 96% at 100 °C compared to polyethylenimine, which showed a change in recovery from 62% to 73%. HACC intercalates into clay platelets, reducing the interlayer spacing between particles and preventing clay from hydrating and swelling. This mechanism of inhibition is evaluated by X-ray diffraction, FTIR, and zeta potential analysis. This bolsters the hypothesis of using the synthesized chitosan derivative as a shale inhibitor.

Preparation of a Lignin-Based Cationic Flocculant and Its Application in Kaolin Suspension Treatment.

The preparation of an environmentally friendly and efficient flocculant for solid-liquid separation in industrial wastewater is highly important. In this study, a novel cationic flocculant (AL-g-PAMA) was synthesized by a thermal initiation method using alkali lignin (AL) as the main chain and acrylamide (AM) and methacrylamido propyl trimethyl ammonium chloride (MAPTAC) as the grafted side chains. The structure, thermal stability, and surface morphology of the copolymers were investigated by various characterization methods. The results indicated the successful synthesis of AL-g-PAMA. AL-g-PAMA was applied to improve solid-liquid separation in kaolin suspensions. The results showed that AL-g-PAMA had excellent flocculation-sedimentation and dewatering efficiency. When the dosage of AL-g-PAMA #5 was 600.0 g/t(s), the thickness of the compressed layer was 2.2 cm, the floc settling velocity was 24.1 cm/min, and the transmittance of the supernatant was 84.0%. The moisture content of the filter cake decreased from 55.0% to 43.4% after treatment with AL-g-PAMA #5. The results of zeta potential and focused beam reflectance measurement (FBRM) analysis indicated that bridging and electroneutralization were the main flocculation mechanisms. Therefore, this study extends the potential for using lignin as a bioflocculant and provides a feasible approach to efficiently purify high-turbidity wastewater.

Study on flocculation performance and mechanism of cationic polyacrylamide on montmorillonite: Insights from experiments and molecular simulations

To achieve efficient flocculation of fine montmorillonite particles, molecular simulation and flocculation test were investigated to explore the influence of cationic monomer on the performance of cationic polyacrylamide (CPAM) flocculating montmorillonite particles. Three cationic monomers including methylacryloxyethyl trimethyl ammonium chloride (DMC), acrylamide propyl trimethyl ammonium chloride (ATMAC), and methylacrylamide propyl trimethyl ammonium chloride (MAPTAC) were copolymerized with acrylamide (AM) to produce CPAM copolymers. The simulation results suggested the electrostatic interaction was the primary internal propelling force for the stable adsorption of three distinct CPAM copolymers on the montmorillonite/water interface, followed by hydrogen bonding. Flocculation test indicated that CPAM has better flocculation effect on fine montmorillonite particles only when it has strong electrostatic adsorption and bridging capacity. This research establishes a theoretical foundation for the structural design of new flocculants for fine clay minerals.

The characteristics and flocculation performance of hydrophobic association poly‐(3‐methacryloylamido propyl trimethyl ammonium chloride)

AbstractThe cationic polymer plays a crucial role in the flocculation process for solid–liquid separation. A hydrophobic‐associated cationic polymer was prepared through micellar free‐radical polymerization of cationic monomer 3‐methyl acrylamide propyl trimethyl ammonium chloride (MAPTAC) and hydrophobic monomer Poly (ethylene glycol) Octadecyl methacrylate (OEMA). The Poly‐MAPTAC‐OEMA can form network structure through intermolecular hydrophobic association in aqueous solution, which leads to the solution viscosity increase and the salt thickening property. The critical associating concentrations (CACs) of Poly‐MAPTAC‐OEMA are 5818–6992 mg/L in aqueous solution. For the diatomite suspensions, at the dosage above about 5 mg/L, the Poly‐MAPTAC‐OEMA can show higher flocculation efficiency compared with Poly‐MAPTAC. Specifically, at the dosage of 8 mg/L, the enhancement rate of sedimentation rate can reach 7.27%–32.31%. Meanwhile, the hydrophobic association mainly enhances the bridging ability but has no significant effect on the improvement of the electric neutralization ability of Poly‐MAPTAC‐OEMA. The flocculation performance‐enhanced dosage of Poly‐MAPTAC‐OEMA is obviously lower than the CAC of Poly‐MAPTAC‐OEMA; this may be because during the flocculation process, the Poly‐MAPTAC‐OEMA first absorb and deeply concentrate on the particle surface, and then the hydrophobic association and bridging enhancement of Poly‐MAPTAC‐OEMA can occur more easily on the particle surface.

The comparison of polymerization activity of typical cationic quaternary ammonium salt monomers

AbstractThe cationic water‐soluble polymers, which are widely used in many areas such as papermaking and separation process, are typically synthesized through polymerization of cationic monomers represented by quaternary ammonium salt. In this work, the polymerization reaction kinetics of three typical quaternary ammonium salt cationic monomers including acryloyl oxygen ethyl trimethyl ammonium chloride (DAC), methyl acryloyl oxygen ethyl trimethyl ammonium chloride (DMC), and methyl acrylamide propyl trimethyl ammonium chloride (MAPTAC) was examined by using the dilatometer method. The results showed that the polymerization rate of all three monomers increased with the increase of initiation temperature, monomer concentration, and initiator concentration. Under the same conditions, the polymerization activity of the three monomers followed the order: DAC > DMC > MAPTAC. The activation energies for the polymerization reaction under the specified conditions were EaDAC = 138.97 kJ/mol, EaDMC = 141.24 kJ/mol, and EaMAPTAC = 226.97 kJ/mol, respectively. The polymerization rate equations were RpDAC = k1[M]4.25[I]0.51, RpDMC = k2[M]3.77[I]0.50, and RpMAPTAC = k3[M]3.30[I]0.49. The polymerization activity of the monomers may be influenced by electronic effects and steric hindrance of the monomer structure. This work has provided a theoretical and experimental foundation for the actual work of structural design and preparation of cationic water‐soluble polymers.

Synthesis of branched cationic flocculant and its performance in treating industrial wastewater with different compositions

This paper proposes a polymer reaction method to introduce a branched structure into cationic polymers' side chains to improve the flocculation performance of the cationic polymer. By using reaction between epoxide compound (EP) and secondary amine in the copolymer (PDD) of methacrylamido propyl trimethyl ammonium chloride (DMC) and diallylamine (DAA), a branched structure was introduced into the side chain of PDD. Three kinds of typical industrial wastewater including sodium humate (NaHA) solution, bentonite suspension, and oilfield produced water (PW) were chosen to be treated by the branched PDD. The pollutants in the three wastewaters had different forms and they were water-soluble organics, solid particles, and liquid droplets, respectively. The effects of flocculant structure and flocculation process on flocculation performance were discussed. The experimental results showed that branched PDD can effectively improve the flocculation performance of PDD. DRE contains an aromatic ring, which may enhance the interaction between PDD-g-DRE and NaHA to promote flocculation. The PDD-g-GTE obtained from the reaction of GTE and PDD contains many hydroxyl groups, which can form hydrogen bonds with the silicon hydroxyl groups on the surface of bentonite to promote flocculation. TDM contains two benzene rings, which made PDD-g-TDM have hydrophobicity. The flocculation can be enhanced because of the hydrophobic interaction between PDD-g-TDM and oil droplets. This work provides a new understanding of the synthesis and performance of branched cationic polymer flocculants.

Studies on Antifungal Properties of Methacrylamido Propyl Trimethyl Ammonium Chloride Polycations and Their Toxicity In Vitro.

The biological activity of polycations is usually associated with their biocidal properties. Their antibacterial features are well known, but in this work, observations on the antifungal properties of macromolecules obtained by methacrylamido propyl trimethyl ammonium chloride (MAPTAC) polymerization are presented. The results, not previously reported, make it possible to correlate antifungal properties directly with the structure of the macromolecule, in particular the molecular mass. The polymers described here have antifungal activity against some filamentous fungi. The strongest effect occurs for polymers with a mass of about 0.5 mDa which have confirmed activity against the multidrug-resistant species Scopulariopsis brevicaulis, Fusarium oxysporum, and Fusarium solani, as well as the dermatophytes Trichophyton mentagrophytes, Trichophyton rubrum, Trichophyton interdigitale, and Trichophyton tonsurans. In addition, this publication describes the effects of these macromolecular systems on serum and blood components and provides a preliminary assessment of toxicity on cell lines of skin-forming cells, i.e., fibroblasts and keratinocytes. Additionally, using a Franz diffusion chamber, a negligibly low transport of the active polymer through the skin was demonstrated, which is a desirable effect for externally applied antifungal drugs. IMPORTANCE Infectious diseases are a very big medical, social, and economic problem. Even before the COVID-19 pandemic, certain infections were among of the most common causes of death. The difficulties in the treatment of infectious diseases concern in particular fungal diseases, against which we have only a few classes of drugs represented by a few substances. The publication presents the preliminary results of the in vitro antifungal activity studies of four MAPTAC polymers on different fungal species and their cytotoxicity to human cells (fibroblasts and keratinocytes). The paper also compares these properties with analogous ones of two commonly used antifungal drugs, ciclopirox and terbinafine.

Aqueous phase synthesis of ion-imprinted cryogel for paper-based colorimetric detection of As(V) with high selectivity.

A novel hydrophilic As(V) ion-imprinted cryogel (IIC) was green prepared by cryogelation in aqueous environment which was coincident with the adsorption condition and can improve the specific recognition performance. The methacrylamido propyl trimethyl ammonium chloride (MPTAC) was selected as the functional monomer and the saturated adsorption capacity of the prepared IIC and NIC were 55.0mg/g and 29.4mg/g, and with high imprinting factor of 1.87. Additionally, the prepared IIC showed admirable reusability and highselectivity, and the recovery was in the range 81.2-97.9% with RSD range of 1.9-4.3%, which was similar to the value obtained by hydride generationatomic absorption spectrometry. IIC can be used as solid material for colorimetric detection at the ultraviolet wavelength of 858nm without color interference of material matrix, in the range 5-200μg/L (R2 = 0.990)with a detection limit of 0.970 µg/L. Obviously, this synthetic strategy provides a simple, efficient, and green method for the preparation of water-compatible ion-imprinted polymers providingselectiveseparation and detection of trace As(V) in real complex samples.

Phase‐Transition‐Triggered Optical Switching for Multistage Information Encryption/Decryption

AbstractIt remains challenging to enable the optical switching for safety‐improved information encryption/decryption on a gel platform. Herein, a water swelling‐induced optical‐switching strategy is reported that can achieve multistage information encryption/decryption on an organohydrogel surface. Cationic moieties of methacrylamido propyl trimethyl ammonium chloride (MPTAC) and hydrophobic fluorophores of (2‐(4‐vinylphenyl) ethene‐1,1,2‐triyl) tribenzene (TPE) are copolymerized into hydrophilic polyacrylamide network. The cationic moieties are capable of increasing the water swelling ability of the network, and the fluorophores endow the network with weak blue fluorescence. Upon low swelling with water (swelling ratio in weight < 50), hydrophobic fluorophores of TPE aggregate to enhance the fluorescence under ultraviolet light. This process is accompanied with the phase transition of organohydrogel into a non‐transparent state. After being saturated with water, the fluorescence disappears and the organohydrogel returns to the transparent state. Such water swelling‐induced optical switching can be used for multistage information encryption/decryption with improved safety. Various information patterns are created on the surface of organohydrogel by laser cutting to demonstrate the complex information encryption/decryption processes. This strategy not only provides a meaningful inspiration for information encryption/decryption but also enables an optical‐switching platform for potential anti‐counterfeiting and displaying.

A strong anion exchanger of poly(glycidyl methacrylate-divinylbenzene) substrate functionalized with cationic quaternary ammonium monomer.

A strong anion exchanger applied for ion chromatography is described by grafting methacrylamido propyl trimethyl ammonium chloride onto hydrolyzed poly(glycidyl methacrylate-divinylbenzene) substrate. The anion exchanger has been in detail characterized and the final capacity of the anion exchanger can be readily manipulated by different monomer amounts. It exhibited obvious temperature-sensitive properties and large tolerance to the samples with high ionic strength. The obtained anion exchanger demonstrated effective separation ability towards the common seven inorganic anions within 12 min and high separation efficiency, for example, 58 000/m of theoretical plate count for chloride.

Thermal Stability of Cationic Poly(3-methacryloylamino Propyl Trimethyl Ammonium Chloride) in Salt Solution

In this paper the thermal stability properties of poly(3-methacryloylamino propyl trimethyl ammonium chloride) (PMAPTAC) with a series of molecular weights in various salt solutions were investigated by monitoring the apparent viscosity and viscosity retention rate with aging time, for the first time to our knowledge. Secondly, the thermal stability properties of poly(methacryloyloxy ethyl trimethyl ammonium chloride) (PDMC) solution was studied and compared with that of the PMAPTAC solution under the same conditions. The results showed that the viscosity retention rate of PMAPTAC/salt solutions with salinities from 40 g/L to 200 g/L at 85 °C were about 60%, indicating that PMAPTAC had good temperature and salt resistance. Besides, the temperature and salt resistance of PMAPTAC with 0.62 dL/g was better than that of PMAPTAC with 7.55 dL/g under the conditions of this study. In addition, the viscosity retention rate of PDMC/salt solution with the same intrinsic viscosity as PMAPTAC/salt solution was 45%, indicating that compared with PDMC, the PMAPTAC with viscosity retention rate of 60% had better temperature and salt resistance. We suggest the results obtained in this study will not only fill the current gaps in the research of the temperature and salt tolerance properties of PMAPTAC, but also provide support for the potential application of PMAPTAC products in high-temperature and high-salt environments.

Study on Hydrolysis Properties and Mechanism of Poly(3-Methacrylamido Propyl Trimethyl Ammonium Chloride) Solution.

Poly(3-methacrylamido propyl trimethyl ammonium chloride) (PMAPTAC) is a typical cationic water-soluble polyelectrolyte, which has been widely used in petroleum, papermaking, daily cosmetics and other fields in the form of an aqueous solution. However, the acid–base and thermal stability of PMAPTAC in aqueous solution have not been reported yet, which hinders its further application in high-temperature and acid–base environments. To address these deficiencies, the effects of temperature and pH of PMAPTAC with different intrinsic viscosities on its hydrolysis stability were investigated qualitatively and quantitatively, and the hydrolysis mechanism was studied. Firstly, the qualitative analysis showed that the apparent viscosity of the PMAPTAC solution decreased with hydrolysis time at different temperatures and pH. The higher the temperature and the lower the pH, the greater the viscosity loss of PMAPTAC. The quantitative analysis showed that the hydrolysis rate of the PMAPTAC sample solution increased with the increase in temperature and pH. In addition, the intrinsic viscosity of PMAPTAC samples had little effect on the hydrolytic stability of PMAPTAC. Secondly, by analyzing the viscosity curves at different pH and temperatures by Arrhenius analysis, the Arrhenius equations were found to be 1/τ = 200.34e^((−25.04)/RT), 1/τ = 9127.07e^((−38.90)/RT) and 1/τ = 4683.03e^((−39.89)/RT) for pH 3, pH 7 and pH 11, respectively. Thirdly, the hydrolysis rate of PDMC was the fastest under alkaline conditions. In addition, compared with PDMC, PMAPTAC had better hydrolysis stability under the same conditions. Finally, the mechanism of the hydrolyzed polymer was studied by FTIR and 13CNMR, which showed that the carbonyl group of PMAPTAC was hydrolyzed into a carboxyl group, and the small molecule (3-aminopropyl) trimethylammonium chloride was generated, while the ester group of PDMC was hydrolyzed into a carboxyl group, and choline chloride was released. The above results can provide a theoretical basis for the application of PMAPTAC in some high-temperature and acid–base environments.

GRAFTING OF BORON-NITROGEN-DOPED CARBON QUANTUM DOTS ON COTTON FABRIC FOR IMPARTING ANTI-ULTRAVIOLET PROPERTIES

"In order to improve the anti-ultraviolet property and laundering durability of cotton fabrics, the cotton fabrics were cationized with epoxy propyl trimethylammonium chloride, and then boron-nitrogen-doped carbon quantum dots (BN-CQDs) were grafted onto the cationized cotton fabrics by the chemical reaction between the quaternary ammonium cation on the cotton fabrics and the carboxyl functional group on the surface of BN-CQDs. The structure, the ultraviolet protection performance and washing durability of the cotton fabrics grafted with BN-CQDs were characterized and tested. The results showed that the resultant cotton fabrics modified with BN-CQDs exhibited a very high ultraviolet protection factor (UPF). Even after 20 consecutive washings, the UPF value was still as high as 75.3, suggesting the promising potential of the modified fabrics as UV protective materials and their excellent laundering durability."

In vivo assessment of the durable, green and in situ bio-functional cotton fabrics based carboxymethyl chitosan nanohybrid for wound healing application

Herein, a newly developed approach for durable antibacterial cotton fabrics coated carboxymethyl chitosan (CMCs) via ionic crosslinking driven by cationization of cotton surface (CC) with 3-chloro-2-hydroxyl propyl-trimethyl ammonium chloride (CHTAC) was achieved. In this regard, the novelty was extended to impart a highly antibacterial activity through harnessing of the as-functionalized CMCs/CC for in situ preparation of AgNPs, without using of hazardous reductants. The antibacterial activity of the in situ prepared AgNPs onto CMCs/CC as well as the in vivo study on the rat lab were investigated to evaluate their healing efficiency, pathological tissues and biomarkers. Results affirmed that the treatment of CC with 10% of CMCs was adequate to achieve the highest swelling ratio which, in turns, is able to in situ deposition of AgNPs with a size range of 2-10 nm onto CC/CMCs rendering them a highly durable antibacterial activity against both Gram +Ve and Gram -Ve bacteria, which had a bacterial reduction of 98% to 86% after 20 washing cycles. Furthermore, the in vivo study revealed effectively the advantageous uses of the cotton functionalized with AgNPs compared to CC/CMCs in wound healing via alleviating the oxidative stress and promoting hyaluronic acid in wounded skin as well as increasing RUNX2 in healed skin tissues.

A strategy for effective recovery of salvianolic acid a from Salvia miltiorrhiza (Danshen) through multiple interactions

Salvianolic acid A (SAA) has high pharmacological activity and is widely used in the treatment of various diseases. We reported herein a strategy for effective adsorption of SAA from aqueous solution by surface molecularly imprinted magnetic nanoparticle (SIMNP). 4-(acryloyloxy)phenylboronic acid, 1-vinylimidazole and methacrylamido propyl trimethyl ammonium chloride were chosen as functional monomers . 1-vinylimidazole not only neutralizes the acidity of SAA solution to help phenylboronic acid react with ortho-phenolic hydroxyl groups of SAA quickly and stably, but also captures SAA through electrostatic interaction and hydrogen bond. Besides, the introduction of positively charged methacrylamido propyl trimethyl ammonium chloride can accelerate the adsorption kinetics . Adsorption kinetically follows a pseudo-second-order model and achieves equilibrium within 10 min at 298.15 K with high selectivity. And the maximum adsorption capacity can be determined to be 1117.6 mg/g by Langmuir adsorption model. Adsorption mechanism involves the formation of covalent bond , electrostatic interaction and hydrogen bond. This work indicates that SIMNP is a promising adsorbent to realize effective capture of SAA from aqueous solution.

Boosting the visible-light-driven photocatalytic antibacterial performance of MoS2 nanosheets by poly(3-(4-methyl-3'-thiophenoxy))propyltrimethylammonium chloride (PThM) modification.

Molybdenum disulfide (MoS2) has been reported to possess photocatalytic bactericidal ability, but its efficiency is not high. In this paper, a water-soluble cationic conjugated polymer, poly(3-(4-methyl-3'-thiophenoxy))propyltrimethylammonium chloride (PThM), was designed to modify MoS2 and boost its antibacterial abilities. Another hydrophobic conjugated polymer, polythiophene (PTh), was synthesized and composited with MoS2, and this was compared with PThM/MoS2 from the perspective of composite effectiveness. Studies involving the photo-disinfection of Escherichia coli (E. coli) under visible-light irradiation (30 W) showed that the antibacterial efficiencies were in the following order: PThM/MoS2 > PTh/MoS2 > MoS2. The enhanced bactericidal activities of PThM/MoS2 and PTh/MoS2 were attributed to the conjugated polymers restraining the recombination of photogenerated carriers in MoS2, thereby increasing the generation of reactive oxygen species (ROS). PThM/MoS2 presented the best antibacterial efficiency because its cationic side-chains improved the solubility of the material and promoted contact between bacteria and the material. This work may provide some insights into the design of practical nano-antibacterial materials.

Complex Formation in the Sulfobetaine-Containing Entirely Ionic Block Copolymer/Ionic Homopolymer System and Their Temperature Responsivity.

The behavior of micelle formation in the sulfobetaine-containing entirely ionic block copolymer/ionic homopolymer system and its functional expression (temperature responsivity) were investigated. Poly(sulfopropyl dimethylammonium propylacrylamide) was used as the sulfobetaine, poly[3-(methacrylamido)propyl trimethylammonium chloride] was used as the cationic polymer, and poly(p-styrenesulfonic acid sodium salt) was used as the anionic polymer. The changes in transition temperature with the concentration and the behavior of micelle formation in the block-/cationic homopolymer and block-/anionic homopolymer system were compared and examined by transmittance, dynamic light scattering, atomic force microscopy, and 1H nuclear magnetic resonance. Only block-/cationic homopolymer systems with a core-shell (polyion complex-sulfobetaine) structure showed temperature responsivity of upper critical solution temperature type, and the responsiveness was dependent on the concentration. On the other hand, the block-/anionic homopolymer system had a core-shell structure at a concentration of 0.05 wt %, but temperature responsiveness was not observed at this concentration. At higher concentrations, electrostatic attraction caused the anionic homopolymer and block copolymer to interact as a whole, resulting in a loss of responsiveness. When the ionic homopolymer had a higher degree of polymerization than the sulfobetaine, it could not form a core-shell structure by interacting with the sulfobetaine and ionic polymer moieties of the block copolymer, thus resulting in the loss of responsiveness. The block-/ionic homopolymer system prepared by the reforming method through dialysis formed uniform and small micelles but lost responsiveness due to morphological stability and electrostatic interaction between the block copolymer and ionic homopolymer.

Physicochemical characterization and flocculation performance evaluation ofPAC/PMAPTACcomposite flocculant

AbstractA novel inorganic–organic composite flocculant was prepared with polyaluminum chloride (PAC) and poly(methacrylamido propyl trimethyl ammonium chloride) (PMAPTAC). To understand the physicochemical characterization of PAC/PMAPTAC and evaluate its flocculation efficiency, the interactions of PAC and cationic polymer were investigated, then the characterization and flocculation performance of PAC/PMAPTAC and PAC/Poly‐dimethyldiallylammonium chloride (PDMDAAC) were compared. The results showed that there were obvious interactions between PAC and cationic polymer in composite flocculant. The cationic polymer chain exhibited a coiled state in PAC solution, and the curly degree of PMAPTAC chain was lower than that of PDMDAAC due to the intermolecular association of methyl of PMAPTAC. The cationic polymer enhanced the charge neutralization ability of PAC and changed the aluminum hydrolysis polymerization species of PAC from low and medium polymeric species to high‐polymeric species. The flocculation sedimentation experiments turned out that the charge neutralization and bridging ability of PAC/PMAPTAC was higher than that of PAC/PDMDAAC, and the increase of molecular weight or content of PMAPTAC in PAC/PMAPTAC could enhance the charge neutralization and adsorption bridging ability simultaneously. The enhanced effects may come from the exist of polymer and the interactions between PAC and cationic polymer in composite flocculant.