Diblock polyampholytes at the silicon–water interface: Adsorption as a function of block ratio and molecular weight

Polyampholytes are highly charged macromolecules carrying oppositely charged functional groups. This article reports on the adsorption of a weak diblock polyampholyte, poly(methacrylic acid)‐block‐poly[(dimethylamino)ethyl methacrylate], as a function of the copolymer composition and molecular weight. The adsorption experiments were performed on silicon substrates from aqueous polymer solutions at different pHs. The amount of adsorbed polyampholyte chains to the surface was determined by ellipsometry, whereas lateral structures were investigated by scanning force microscopy. A strong influence of pH on the adsorbed amount and the lateral structure formation at the surface was observed. Especially at the isoelectric point, drastic changes in adsorption behavior were detected. At low molecular weights, an increased adsorbed amount was detected, a behavior in contrast to common theoretical predictions. This phenomenon is explained by the high stability of absorbed micelles, which cover the silicon surface as a dense layer. We conclude that micelle formation is an important process for polyampholyte adsorption, which needs to be taken into account more explicitly. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 709–718, 2001     

Adsorption of block polyampholyte micelles in monolayers at the silicon water interface

 The adsorption of the diblock polyampholyte poly (methacrylic acid)-block-poly((dimethylamino)ethyl methacrylate) from aqueous solution on silicon substrates was investigated as a function of polymer concentration and pH. Dynamic light scattering and electrokinetic measurements were used to characterize the polyampholyte in solution. The amount of polymer adsorbed was determined by ellipsometry and lateral structures of the polymer layer were investigated by scanning force microscopy. The amount of polymer adsorbed was found to be strongly influenced by the pH of the polymer solution, while the size of the polyampholyte micelles adsorbed on the surface was hardly affected by pH during adsorption. From investigations by scanning force microscopy well-seperated micelles were seen in the dried monolayers adsorbed directly from solution. The structures at the surface are correlated to structures in solution, and the adsorbed amount depends on the relative charge of the micelles and the surface. Received: 13 September 1999 Accepted in revised form: 8 December 1999     

Adsorption and structure formation of the weak polyelectrolytic diblock copolymer,PVP-<Emphasis Type="Italic">b</Emphasis>-PDMAEMA

This paper reports on the pH-dependent adsorption of weak the polyelectrolytic diblock copolymer poly(2-vinylpyridine)-block-poly(dimethylaminoethyl methacrylate), (PVP-b-PDMAEMA). Aqueous PVP-b-PDMAEMA solutions have been adsorbed on alkaline pretreated silicon substrates. Altogether two copolymers differing in block ratio and molecular weight were used for the investigations. While the electrical charge of both samples in solution was investigated by electrophoretic measurements, the adsorbed polymer layers were studied with ellipsometry and atomic force microscopy (AFM). Depending on pH the electrical charge of both blocks of the diblock copolymer varied. Three different regimes have been identified. Under acidic conditions at pH<5, both blocks are mainly positively charged. At medium pH between 5 and 8, only the PDMAEMA block is positively charged. At pH>8, both blocks are nearly uncharged and a polymer precipitation occurred in solution. Each of these pH regimes was characterized by a specific adsorption behaviour leading to two adsorption maxima at acidic and alkaline pH values, while at medium pH a plateau in the adsorbed amount was observed. Moreover, the structures of the polyelectrolytes formed on the substrate after adsorption were specific to each of the three pH regimes.     

Synthesis of double‐hydrophilic block copolymers via combination of oxyanion‐initiated polymerization and polymer reaction for fabricating magnetic target gene carrier

In this work, we have synthesized a polycation and a polyanion via a combination of oxyanion‐initiated polymerization and polymer reaction, and then developed a novel approach to prepare a controlled magnetic target gene carrier with magnetic Fe₃O₄ nanoparticles as core and poly(ethylene glycol) (PEG) segment as corona via layer‐by‐layer (LbL) assembly and shell‐crosslinking. Magnetic nanoparticles (MNPs) were first modified by poly[2‐(dimethylamino)ethyl methacrylate] (PDMAEMA) via radical polymerization. The resulting MNPs were used to compact deoxyribonucleic acid (DNA) through LbL assembly, involving four steps: ( 1 ) the binding of DNA to the polycation PDMAEMA on the surface of MNPs; ( 2 ) the produced particles in Step 1 with negative charge interacting with additional polycation ethoxy group end‐capped PDMAEMA (EtO‐PDMAEMA) homopolymer, leading to a positive charge surface; ( 3 ) using carboxyl group (‐COO^‐) of poly(methacrylic acid) (PMAA) in a diblock copolymer (MePEG2000‐b‐PMAA_SH) as polyanion, which has partial mercapto groups (‐SH) in PMAA segment, to interact with the particles produced in Step 2; ( 4 ) the shell of the composite nanoparticle was crosslinked by oxidizing the ‐SH groups of the MePEG2000‐b‐PMAA_SH to form disulfide linkage (S? S). All the processes of LbL assembly were investigated by agarose gel retardation assay and zeta potential measurements. The in vitro cytotoxicity analysis proves that polyions/DNA MNPs have excellent properties and potential applications as gene carriers. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Swelling of poly(methacrylic acid) gels and adsorption of L-lysine and its polymer on the gels

Poly (methacrylic acid) gels (PMAA gels) of various degrees of crosslinking were prepared and the dissociation behavior of these gels was examined; the swelling behavior was investigated as a function of the solution pH values. A reentrant phenomenon of swelling was observed and interpreted based on the Flory-Huggins equation and the Donnan equilibrium formula. Moreover, adsorption of L-lysine, oligo(L-lysine)s (Lys-n,n=3, 9, and 19) and poly(L-lysine) onto PMAA gels from aqueous solutions was investigated under different conditions of pH and concentration of adsorbate. The adsorption ratio of L-lysine onto PMAA gel is dependent on both the pH of solution and the degree of crosslinking. In a pH range between 8 and 9, the protonated form of L-lysine is strongly adsorbed on the PMAA gel by electrostatic interactions. Oligomers and polymer of L-lysine are adsorbed in a somewhat different way from the monomeric L-lysine. In addition, the desorption behavior of L-lysine from PMAA gels by a change in pH was also investigated.     

Polyelectrolyte complex nanoparticles from N‐carboxyethylchitosan and polycationic double hydrophilic diblock copolymers

For the first time, the polyelectrolyte complex (PEC) formation tool was used for preparation of core‐shell nanoparticles form the natural polyampholyte N‐carboxyethylchitosan (CECh) and weak polycationic (protonated) polyoxyethylene‐b‐poly[2‐(dimethyl‐amino)ethyl methacrylate] (POE‐b‐PDMAEMA) diblock copolymers. The performed dynamic light scattering analyses revealed that nanoparticles with a PEC core and a POE shell could be formed at mixing ratio between the oppositely charged groups equal to 1/1 depending on CECh molar mass, polymerization degree of PDMAEMA block and ionic strength. The results were confirmed by the performed AFM and cryo‐TEM analyses. When high molar mass CECh was used, core‐shell nanoparticles were obtained with the diblock copolymer of the shortest PDMAEMA block at ionic strength (I) of 0.01. At ionic strength value close to the physiological one (I = 0.1) secondary aggregation occurred. Spherical nanoparticles at I = 0.1 were obtained upon lowering the CECh molar mass. Depending on the polymer partners and medium parameters the size of the obtained particles varied from 60 to 600 nm. The X‐ray photoelectron spectra evidenced the hydrophilic POE‐block shell—coacervate CECh/PDMAEMA‐block core structure. The nanoparticles are stable in a rather narrow pH range around 7.0, thus revealing the high pH‐sensitivity of the obtained core‐shell particles. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2105–2117, 2009     

Stimuli‐responsive amphiphilic PDMAEMA‐b‐PLMA copolymers and their cationic and zwitterionic analogs

In this work, the synthesis and characterization of novel amphiphilic diblock copolymers of poly(2‐dimethylamino ethyl methacrylate)‐b‐poly(lauryl methacrylate), PDMAEMA‐b‐PLMA, using the reversible addition‐fragmentation chain transfer (RAFT) polymerization technique, are reported. The diblocks were successfully derivatized to cationic and zwitterionic block polyelectrolytes by quaternization and sulfobetainization of the PDMAEMA block, respectively. Furthermore, their molecular and physicochemical characterization was performed by using characterization techniques such as NMR and FTIR, size exclusion chromatography, light scattering techniques, and transmission electron microscopy. The structure of the diblock micelles, their behavior, and properties in aqueous solution were investigated under the effect of pH, temperature, and ionic strength, as PDMAEMA and its derivatives are stimuli‐responsive polymers and exhibit responses to variations of at least one of these physicochemical parameters. These new families of stimuli‐responsive block copolymers respond to changes of their environment giving interesting nanostructures, behavioral motifs, and properties, rendering them useful as nanocarriers for drug delivery and gene therapy. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 598–610     

Formation of polyampholyte brushes via controlled radical polymerization and their assembly in solution

We describe the formation of polyampholytic block copolymer brushes and their assembly in solution. Specifically, we employ "surface-initiated" activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP) sequentially to form diblock copolymer grafts comprising blocks of poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) and poly(sodium methacrylate) (PNaMA) on flat impenetrable silica surfaces, i.e., SiO(x)/PNaMA-b-PDMAEMA and SiO(x)/PDMAEMA-b-PNaMA. Protonation of the PNaMA block results in formation of poly(methacrylic acid) (PMAA). We demonstrate that ARGET-ATRP of NaMA provides a convenient route to preparation of PMAA, which is an alternative method to the more traditional approach based on preparing PMAA by polymerizing tert-butyl methacrylate (tBMA) followed by cleavage of the tert-butyl group. We also discuss conformational changes of the individual polyelectrolyte blocks in solution as a function of solution pH by monitoring adsorption behavior of functionalized polystyrene spheres.     

Stimuli-responsive surfaces using polyampholyte polymer brushes prepared via atom transfer radical polymerization

The synthesis of AB diblock copolymer polyampholyte polymer brushes of the type Si/SiO2//poly(acrylic acid-b-vinyl pyridine) prepared using atom transfer radical polymerization is reported. Both 2- and 4-vinyl pyridine have been used. The diblock polyampholyte polymer brushes demonstrate stimuli-responsive behavior with respect to pH, showing both polyelectrolyte and polyampholyte effects. Furthermore, we have quaternized the 4-vinyl pyridine segments to form a mixed weak/strong, or annealed/quenched, polyelectrolyte system. The quaternized polymer brush exhibits different pH-responsive behavior, with decreasing film thickness being observed with increasing pH.     

Morphological investigation of polydisperse asymmetric block copolymer systems of poly(styrene) and poly(methacrylic acid) in the strong segregation regime

Samples of compositionally (highly) asymmetric diblock copolymers and, also, mixtures of diblock and triblock copolymers (the latter obtained as end‐coupling products of two diblock molecules of the mixture), composed of (a) monodisperse majority block(s) of poly(styrene) (PS) and a polydisperse minority block of poly(methacrylic acid) (PMAA), microphase separate into spherical PMAA microdomains, either in disordered liquid‐like state or body‐centered‐cubic (BCC) arrangement, at various annealing temperatures T, in the strong segregation regime SSR. We found that (i) the microphase separated state is favored over an anticipated molecularly homogenous state, (ii) the spherical microdomain morphology (with BCC symmetry) is favored over an anticipated hexagonally packed cylindrical morphology, (iii) the extent of the dissolution of short PMAA blocks in the PS material can be quantified, (iv) the spherical microdomains are dilated, and (v) despite molecular‐weight (and architectural) polydispersity, well‐ordered BCC structures can be obtained. © 2013 Wiley Periodicals, Inc. J. Polym. Sci. Part B: Polym. Phys. 2013 , 51, 1657–1671     

Synthesis and micellization of PSt‐PNIPAM‐PDMAEMA hetero‐arm star polymer with double thermo‐responsibility

A hetero‐arm star polymer, polystyrene‐poly(N‐isopropylacrylamide)‐ poly(2‐(dimethylamino)ethylmethacrylate) (PSt‐PNIPAM‐PDMAEMA), was synthesized by “clicking” the alkyne group at the junction of PSt‐b‐PNIPAM diblock copolymer onto the azide end‐group of PDMAEMA homopolymer via 1,3‐dipolar cycloaddition. The resultant polymer was characterized by gel permeation chromatography, proton nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy. PSt‐PNIPAM‐PDMAEMA micelles with PSt block as core and PNIPAM and PDMAEMA blocks as shell were formed when adding the copolymer solution in THF into 10 folds of water. Lower critical solution temperature (LCST) of PNIPAM and PDMAEMA homopolymer is 32 °C for PNIPAM and 40 to 50 °C for PDMAEMA, respectively. Upon continuous heating through their LCSTs, PSt‐PNIPAM‐PDMAEMA core‐shell micelles exhibited two‐stage thermally induced collapse. The first‐stage collapse, from 20 to 34 °C, is ascribed to the shrinkage of PNIPAM chains; and the second‐stage collapse, from 38 to 50 °C, is due to the shrinkage of PDMAEMA chains. Dynamic light scattering was used to confirm the double phase transitions. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 786–796, 2009     

Structured multistimuli‐responsive functional polymer surfaces obtained by interfacial diffusion of amphiphilic block copolymers

Herein, we report the preparation of structured multistimuli‐responsive surfaces able to change reversibly both their chemical composition depending on the environment and their surface behavior by varying either/both the pH or/and the temperature. For that purpose, we took advantage of the surface segregation in homopolymer/diblock copolymer blends, composed of either polystyrene‐block‐poly(N,N′‐dimethylaminoethylmethacrylate) (PS‐b‐PDMAEMA) or polystyrene‐block‐poly (N,N′‐diethylaminoethylmethacrylate) (PS‐b‐PDEAEMA) and high molecular weight polystyrene used as a matrix. The variations of the surface composition as a function of the environment of exposure (air or water vapor) was investigated were investigated by XPS and contact angle measurements. The water‐annealed surfaces contain PDMAEMA or PDEAEMA at the surface and are additionally able to respond both to pH and temperature as demonstrated by the Wilhelmy technique. Both PDMAEMA and PDEAEMA can switch from a hydrophilic state to a collapsed hydrophobic state increasing the temperature above the LCST. More interestingly, as a result of the microphase separation of the block copolymers at the interface, the surfaces of the blends exhibit structuration. Thus, either micellar structures or “donut‐like” morphologies were obtained by using THF or toluene, respectively, as solvent. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1952–1961, 2010     

Monomer volume fraction profiles in pH responsive planar polyelectrolyte brushes

Spatial dependencies of monomer volume fraction profiles of pH responsive polyelectrolyte brushes were investigated using field theories and neutron reflectivity experiments. In particular, planar polyelectrolyte brushes in good solvent were studied and direct comparisons between predictions of the theories and experimental measurements are presented. The comparisons between the theories and the experimental data reveal that solvent entropy and ion‐pairs resulting from adsorption of counterions from the added salt play key roles in affecting the monomer distribution and must be taken into account in modeling polyelectrolyte brushes. Furthermore, the utility of this physics‐based approach based on these theories for the prediction and interpretation of neutron reflectivity profiles in the context of pH responsive planar polyelectrolyte brushes such as polybasic poly(2‐(dimethylamino)ethyl methacrylate) (PDMAEMA) and polyacidic poly(methacrylic acid) (PMAA) brushes is demonstrated. The approach provides a quantitative way of estimating molecular weights of the polymers polymerized using surface‐initiated atom transfer radical polymerization. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 956–964     

Adsorption of randomly annealed polyampholytes at the silica-water interface

We have investigated the adsorption of randomly annealed polyampholytes containing [2-(dimethylamino)ethyl methacrylate)] (DMAEMA), methacrylic acid (MAA), and [3-(2-methylpropionamido)propyl] trimethylammonium chloride (MAPTAC) with various molar compositions. The adsorption was performed from dilute aqueous solutions onto silicon substrates. The adsorbed layers were characterized by reflectivity techniques such as reflectometry, ellipsometry, and neutron specular reflection. As expected for annealed polyampholytes, the adsorption was found to depend strongly on the pH, with a maximum within the isoelectric domain of the polyampholyte. The monomer volume fraction profiles of the adsorbed layers were determined from neutron specular reflection measurements. In the isoelectric domain, the polyampholyte chains adopt a compact conformation, with a layer thickness of about 60 A. The polyampholyte layer is as dense as the adsorbed layer of fully charged polyelectrolyte but much thicker. Finally, we found that changing the ratio of neutral units along the polyampholyte chain in the isoelectric domain had no significant effect on the concentration profile of the adsorbed layer.     

Completely aqueous procedure for the growth of polymer brushes on polymeric substrates

The growth of polymer brushes on polymer substrates is often challenging because of substrate incompatibility with the organic solvents used for initiator attachment. This letter reports the use of layer-by-layer adsorption of macroinitiators and subsequent aqueous ATRP from these immobilized initiators to prepare polymer brushes on polymeric substrates. Polyethersulfone (PES) films and porous membranes were modified with polyelectrolyte multilayer films, and a previously developed polycationic initiator, poly(2-(trimethylammonium iodide)ethyl methacrylate-co-2-(2-bromoisobutyryloxy)ethyl acrylate), was then electrostatically adsorbed onto these polyelectrolyte films. The immobilized macroinitiator is very efficient in initiating the growth of polymer brushes on PES, as demonstrated by aqueous syntheses of poly(2-hydroxyethyl methacrylate) (PHEMA) and poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) films. PHEMA (250 nm thick) and PDMAEMA (40 nm thick) brushes were grown in 2 h from surfaces modified with polycationic initiators. Moreover, this procedure is effective for growing brushes in the pores of PES membranes.     

Complexation of linear and poly(ethylene oxide)‐grafted poly(methacryl oxyethyl trimethylammonium chloride) with poly(ethylene oxide‐block‐sodium methacrylate)

The interactions between oppositely charged polyelectrolytes were studied in saline aqueous solutions as functions of the temperature and the salt and polymer concentrations. The polyanion was a diblock copolymer composed of a poly(ethylene oxide) block and a poly(sodium methacrylate) block. Two polycations were used, the homopolymer poly(methacryl oxyethyl trimethylammonium chloride) and its poly(ethylene oxide)‐grafted analogue. By dynamic light scattering and turbidity measurements, it was observed that the salt concentration, temperature, and counterion size had a significant effect on the formation of the polymer complexes in aqueous solutions. At a fixed salt concentration and a fixed temperature, it was possible to form completely soluble complexes of an ionic polymer in aqueous solutions between poly(ethylene oxide)‐grafted poly(methacryl oxyethyl trimethylammonium chloride)and the polyanion with a poly(ethylene oxide) block at a 1:1 anion/cation ratio. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1904–1914, 2003     

Normal and shear forces between a polyelectrolyte brush and a solid surface

The diblock copolymer poly(methyl methacrylate)‐b‐poly(sodium sulfonated glycidyl methacrylate) (PMMA‐b‐PSGMA) was end‐attached by its hydrophobic block (PMMA) onto mica hydrophobized by a stearic trimethylammonium iodide (STAI) layer, to form a polyelectrolyte brush immersed in water. With a surface force balance (SFB), we extended earlier measurements between two such brush layers for the case of normal and shear forces at different shear rates, surface separation, and compressions between one mica surface coated with STAI or a STAI‐diblock layer against a bare mica surface. After coating one of the surfaces with STAI, a long range attraction that results in a jump into an adhesive flat contact between the hydrophobic and hydrophilic surfaces was observed. A very different behavior was seen after forming the polyelectrolyte brush on the STAI‐coated surface. The long range attraction was replaced by repulsion, accompanied by very low friction during shear (ca. three orders of magnitude lower than with adsorbed polyelectrolytes). On further compression, a weak attraction to the adhesive contact was observed. From the final surface–surface contact separation, we deduce that most of the polyelectrolyte diblock brush layer was squeezed out from the gap, leaving the STAI layer and a small amount of the polymer attached to the surface. Stick‐sliding behavior was seen while applying shear, suggesting a dissipation mechanism caused by the trapped polyelectrolyte. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 193–204, 2005     

pH-responsive diblock copolymer micelles at the silica/aqueous solution interface: Adsorption kinetics and equilibrium studies

The adsorption behavior of two examples of a weakly basic diblock copolymer, poly(2-(dimethylamino)ethyl methacrylate)-block-poly(2-(diethylamino)ethyl methacrylate) (PDMA-PDEA), at the silica/aqueous solution interface has been investigated using a quartz crystal microbalance with dissipation monitoring and an optical reflectometer. Dynamic and static light scattering measurements have also been carried out to assess aqueous solution properties of such pH-responsive copolymers. In alkaline solution, core-shell micelles are formed above the critical micelle concentration (cmc) by both copolymers, whereas the chains are molecularly dissolved (as unimers) at all concentrations in acidic solution. As a result, the adsorption behavior of PDMA-PDEA diblock copolymers on silica is strongly dependent on both the copolymer concentration and the solution pH. Below the cmc at pH 9, the cationic PDMA-PDEA copolymers adsorb as unimers and the conformation of the adsorbed polymer is essentially flat. At concentrations just above the cmc, the initial adsorption of copolymer onto the silica is dominated by the unimers due to their faster diffusion compared to the much larger micelles. Rearrangement of the adsorbed unimers and/or their subsequent displacement by micelles from solution is then observed during an equilibration period, and the final adsorbed mass is greater than that observed below the cmc. At concentrations well above the cmc, the much higher proportion of micelles in solution facilitates more effective competition for the surface at all stages of the adsorption process and no replacement of initially adsorbed unimers by micelles is evident. However, the adsorbed layer undergoes gradual rearrangement after initial adsorption. This relaxation is believed to result from a combination of further copolymer adsorption and swelling of the adsorbed layer.     

Reversible pH-controlled switching of poly(methacrylic acid) grafts for functional biointerfaces

Responsive polymeric brushes of poly(methacrylic acid) (PMAA) were grafted from silicon surfaces using controlled surface-initiated atom-transfer radical polymerization (SI-ATRP). The growth kinetics of PMAA was investigated with respect to the composition of the ATRP medium by grafting the polymer in mixtures of water and methanol with different ratios. The dissociation behavior of the polymer layers was characterized by FTIR titration after incubating the polymer-grafted substrates in PBS buffer solutions with different pH values. PMAA layers show a strong pH-dependent behavior with an effective pK(a) of the bulk polymer brush of 6.5 ± 0.2, which is independent of the polymer brush thickness and methanol content of the ATRP grafting medium. The pH-induced swelling and collapse of the grafted polymer layers were quantified in real time by in situ ellipsometry in liquid environment. Switching between polymer conformations at pH values of 4 and 8 is rapid and reversible, and it is characterized by swelling factors (maximum thickness/minimum thickness) that increase with decreasing the methanol content of the SI-ATRP medium.     

New antibacterial cationic surfactants prepared by atom transfer radical polymerization

Efficient antibacterial surfactants have been prepared by the quaternization of the amino groups of poly(ethylene‐co‐butylene)‐b‐poly[2‐(dimethylamino)ethylmethacrylate] (PEB‐b‐PDMAEMA) diblock copolymers by octyl bromide. The diblock copolymers have been synthesized by ATRP of 2‐(dimethylamino)ethylmethacrylate (DMAEMA) initiated by an activated bromide‐end‐capped poly(ethylene‐co‐butylene). In the presence of CuBr, 1,4,7,10,10‐hexamethyl‐triethylenetetramine (HMTETA), and toluene at 50 °C, the initiation is slow in comparison with propagation. This situation has been improved by the substitution of CuCl for CuBr, all the other conditions being the same. Finally, the addition of an excess of CuCl₂ (deactivator) to the CuCl/HMTETA catalyst is very beneficial in making the agreement between the theoretical and experimental number‐average molecular weights excellent. The antibacterial activity of PEB‐b‐PDMAEMA quaternized by octyl bromide has been assessed against bacteria and is comparable to the activity of a commonly used disinfectant, that is, benzalkonium chloride. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1214‐1224, 2006