Copolymerization Of Monomers Research Articles

The effect of molecular structure on the properties of cationic polyacrylate and its flocculation‐flotation performance of oilfield oily wastewater treatment

AbstractWith the increasing amount of oily wastewater produced in the offshore oilfield, more efficient air flotation agent is needed to be developed. Cationic polyacrylate with amphiphilic structure has been found to be a type of potential efficient air flotation agent. However, the effect of molecular structure on its properties and performance was lack of research. In this paper, copolymers with tertiary amine as side group were synthesized by copolymerization of ethyl acrylate (EA) and tertiary amine monomers, and then a series of cationic polyacrylates were prepared by quaternization of tertiary amine with quaternization reagent. The effects of tertiary amine monomer type (including dimethylaminopropyl methacrylamide (DPM) and dimethylaminoethyl methacrylate (DEM)), quaternization reagent type (including 3‐Chloro‐1,2‐Propanediol and 3‐chloro‐2‐hydroxytrimethylammonium chloride) and quaternization degree on the cationic polyacrylate properties and its flotation performance were investigated. The experimental results showed that the flotation performance increased with the increasing hydrophilicity and cation degree of the hydrophilic unit in the cationic polyacrylate. When the tertiary amine monomer was DPM, quaternization reagent was 3‐chloro‐2‐hydroxytrimethylammonium chloride, and theoretical quaternization degree was 100%, the oil removal of product PE‐M‐1.0 was the highest. When PE‐M‐1.0 dosage was 50 mg/L, gas flow was 1 L/min, flotation time was 10 min, its oil removal rate was higher than 95% in the range of 20‑60°C. The results of zeta potential measurement and microfluidic experiment showed that PE‐M‐1.0 can increase the size of oil droplets by destroying the electric double layer on the surface of oil droplets and maintain the stability of bubbles, which was helpful for the improve of gas bubble‐oil droplet collision probability and adhesion efficiency.

New advances in olefin homo and copolymerization using neutral, single component palladium/nickel complexes ligated by a phosphine-sulfonate

Use of catalysts for olefin homo- and copolymerization has received growing attention in recent decades. Most polyolefins especially polyethylene and polypropylene are currently produced in the presence of transition-metal catalysts. So far, late transition-metal catalysts particularly nickel and palladium-based complexes have attracted great attention and various ligands have been employed in the structure of these catalysts. In this contribution, nickel and palladium-based complexes with symmetrical cationic α-diimine (as Brookhart catalysts) and non-symmetrical neutral phosphine-sulfonate ligands (as Drent catalysts) have been extensively utilized as olefin (co)polymerization catalysts. Unlike classic α-diimine complexes, the generation of highly linear ethylene/polar monomer copolymers, prepared in the absence of co-catalyst by phosphine-sulfonate palladium/nickel catalysts poses an interesting case. The outstanding features of phosphine-sulfonate-based catalysts motivated many researchers to focus on these catalysts. In this context, several review articles have covered various aspects of this class of catalysts. Considering the importance of phosphine-sulfonate-based catalysts, in this mini-review, we wish to address recent advances of the neutral, single component palladium/nickel complexes bearing phosphine–sulfonate ligands for olefin (co)polymerization with polar monomers.

NIR Responsive Injectable Nanocomposite Thermogel System Against Osteosarcoma Recurrence.

Compared to traditional postoperative radiation and chemotherapy, immune checkpoint blockade (ICB) therapy demonstrates superiority by provoking own immune system to cure cancer completely even for some terminally ill patients. However, systemic administration of ICB is liable to cause severe immunity inflammation or immune storm. Here, an injectable, near infrared (NIR) responsive, multifunctional nanocomposite thermogel as a local ICB delivery system for cancer postsurgical therapy is proposed. By copolymerization of thermosensitive and zwitterionic monomer, the injectable thermogel with adjustable sol-gel transition temperature is obtained. Afterward, combined with functional mesoporous nanoparticles, the platform can absorb NIR light and transfer it into heat. The generated heat will promote retro Diels-Alder (D-A) reaction to degrade coating layer on nanoparticle, achieving NIR controlled ICB release. Furthermore, the local ICB delivery system is applied on an osteosarcoma postsurgical recurrence model and results indicate the platform with favorable biocompatibility can avoid early leakage of cargos and greatly increase drug content at tumor site. Besides, long-term controlled ICB release of the system effectively improves the amount of active T cells, resulting in excellent antitumor recurrence effect. Overall, this work suggests the local injectable nanocomposite thermogel is expected to be a promising tool for cancer postoperative therapy.

Advances in the Synthesis of Copolymers from Carbon Dioxide, Dienes, and Olefins.

Carbon dioxide (CO2) has long been considered a sustainable comonomer for polymer synthesis due to its abundance, easy availability, and low toxicity. Polymer synthesis from CO2 is highly attractive and has received continuous interest from synthetic chemists. In this regard, alternating copolymerization of CO2 and epoxides is one of the most well-established methods to synthesize aliphatic polycarbonates. Moreover, binucleophiles including diols, diamines, amino alcohols, and diynes have been reported to copolymerize with CO2 to give polycarbonates, polyureas, polyurethanes, and polyesters, respectively. Nevertheless, little success has been made for incorporating CO2 into the most widely used polyolefin materials.Although extensive studies have been focused on the copolymerization of olefins and CO2, most of the attempted reactions resulted in olefin homopolymerization owing to the endothermic property and high energy barriers of CO2 insertion during the chain propagation process. In this Account, we show how this challenge is addressed by taking advantage of a metastable lactone intermediate, 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one (EVP), which is produced from CO2 and butadiene via palladium catalysis. Homopolymerization of EVP furnishes CO2/butadiene copolymers with up to 29 wt % of CO2 content. This reaction strategy represents a breakthrough for the long-standing challenge of inherent kinetic and thermodynamically unfavorable CO2/olefin copolymerization. A new class of polymeric materials bearing repeating bicyclic lactone and unsaturated lactone units can be obtained. Importantly, one-pot copolymerization of CO2/butadiene or terpolymerization of CO2/butadiene/diene can be achieved to afford copolymers through a two-step reaction protocol. Interestingly, the bicyclic lactone units in the polymer chain can undergo ring-opening through hydrolysis and aminolysis, while reversible ring-closing of the hydrolyzed or aminolyzed units was also achieved simply by heating.Over the past few years, more and more studies have utilized EVP as an intermediate to synthesize copolymers from olefins, butadiene, and CO2. Recently, we successfully incorporated CO2 into the most widely used polyethylene materials via the direct copolymerization of EVP and ethylene. Taking advantage of the bifunctional reactivity of EVP, we were able to access two types of main-chain-functionalized polyethylenes through palladium-catalyzed coordination/insertion copolymerization and radical copolymerization. Besides polyethylenes, CO2 was also incorporated into poly(methyl methacrylate), poly(methyl acrylate), polystyrene, polymethyl acrylate, polyvinylchloroacetate, and poly(vinyl acetate) materials via radical copolymerization of EVP and olefin monomers. The EVP/olefin copolymerization strategy provides a novel avenue for the synthesis of highly versatile copolymers from an olefin, CO2, and butadiene.

Swelling Behavior of Lipophilic Polyelectrolyte Gels in Organic Solvents−Water or Sea Water Binary Mixtures

AbstractThe recovery of crude oil and volatile organic compounds (VOCs) spilt in the environment is an intractable problem for environmental scientists. In this paper, a new lipophilic polyelectrolyte gel as an absorbent for various volatile chemical compounds is demonstrated. It is prepared by radical copolymerization of an acrylate monomer with an ionic group, tetraalkylammonium tetraarylborate, octadecyl acrylate, and a crosslinker, dipropylene glycol diacrylate, in the presence of a radial initiator. Investigation of the swelling behavior for the mixtures of water or aqueous salts reveals that the gel shows similar swelling behavior to those for pure organic solvents. On the other hand, the swelling degree in THF‐water mixture is lower than that of pure THF, because THF and water are miscible to each other, and the presence of a small amount of water in THF reduces the compatibility of the gel and THF. The salting‐out effect can separate the THF‐water mixture to form a biphasic system and recover the high swelling ability of the gel. The swelling behavior in the mixture of water‐organic solvents systems provides a new insight for designing VOC and oil absorbents in various environmental conditions, especially in hydrosphere such as seas and lakes.

Electrically Accelerated Self-Healable Polyionic Liquid Copolymers.

Electrically accelerated self-healable poly(ionic liquids) copolymers that exhibit resistor-capacitor (RC) circuit properties are developed. At low alternating current (AC) frequencies these materials behave as a resistor (R), whereas at higher frequencies as a capacitor (C). These properties are attributed to a combination of dipolar and electrostatic interactions in (1-[(2-methacryloyloxy)ethyl]-3-butylimidazolium bis(trifluoromethyl-sulfonyl)imide) copolymerized with methyl methacrylate (MMA) monomers to form p(MEBIm-TSFI/MMA)] copolymers. When the monomer molar ratio (MEBIm-TSFI:MMA) is 40/60, these copolymers are capable of undergoing multiple damage-repair cycles and self-healing is accelerated by the application of alternating 1.0-4.0V electric field (EF). Self-healing in the absence of EFs is facilitated by van der Waals (vdW) interactions, but the application of AC EF induces back and forth movement of charges against the opposing force that result in dithering of electrostatic dipoles giving rise to interchain physical crosslinks. Electrostatic inter- and intrachain interactions facilitated by copolymerization of ionic liquid monomers with typically dielectric acrylic-based monomers result in enhanced cohesive energy densities that accelerate the recovery of vdW forces facilitating self-healing. Incorporating ionic liquids into commodity polymers offers promising uses as green conducting solid polyelectrolytes in self-healable energy storage, energy-harvesting devices, and many other applications.

Amine-Containing Monomers for Ring-Opening Metathesis Polymerization: Understanding Chelate Effects in Aryl- and Alkylamine-Functionalized Polyolefins

Ring-opening metathesis polymerization (ROMP) of two different types of amine-functionalized monomers, aminonorbornenes (ANs) and aminocyclooctenes (ACs), has been studied using [(H2IMes)(PCy3)(Cl)2Ru = CHPh] Grubbs second generation catalyst, G2, and [(H2IMes)(pyr)2(Cl)2Ru = CHPh] Grubbs third generation catalyst, G3. Despite the known detrimental effects of unprotected amine functionalities on Ru-based ROMP catalysts, aminopolyolefins can be readily prepared using G2 and G3. The influence of the amine substituent of the monomer on the polymerization process, as probed by monitoring reaction kinetics, confirmed that the basicity/nucleophilicity of the amine group has a detrimental influence on the ROMP process. Reaction kinetics of homopolymerization of both these classes of monomers revealed faster polymerization of ACs than the more strained AN counterpart, which has been attributed to the favored chelated catalyst resting states in the case of ANs. Hammett studies show increased polymerization rates in the presence of electron-withdrawing aryl amine-containing monomers. These observed kinetic effects were used to advantage in the copolymerization of AN and AC monomers to access a gradient polymer. Polymerization kinetics of combined monomers displayed different reactivity profiles than observed during homopolymerization. Polyolefins with unprotected secondary alkyl amines could be synthesized by leveraging the unfavorable chelate formation in the case of AC monomers. The strategic selection of cyclic alkene and relative positioning of amine substituent allows for the diverse incorporation of secondary amines into polymers by ROMP.

Chemical Imprinting Technology Applied to Analytical Chemistry: Current Status and Future Outlook in Brazil

Chemical imprinting technologies based on molecularly imprinted polymers (MIPs) and ion imprinted polymers (IIPs) have been widely applied in different fields of analytical chemistry since their discoveries in 19721 and 19762, respectively. MIPs and IIPs are considered biomimetic materials with tailor-made synthetic receptors and are, essentially, obtained by co-polymerization of functional and cross-linking monomers in the presence of a target analyte (a molecule for MIPs and an ion for IIPs). The great advantages of these materials over biological recognition systems include their relatively low cost, quick preparation, and, most importantly, their stability in different media. To date, these biomimetic materials have experienced a rapid development with wide applications in electrochemical sensors, luminescence sensors, separation science, sample preparation, and more specific sensor applications such as surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) sensors. In addition, they have been applied for analysis of samples of environmental, food, and forensic interests, as well as for disease diagnostics.3-8 Figure 1 depicts the increasing number of published papers per year over the past 20 years on the topic of MIPs and IIPs; as expected, most of these papers are devoted to the chemical imprinting of molecules.

Free radical solution copolymerization of monomers of dissimilar reactivity - influencing chemical composition distribution and properties of copolymers of methyl methacrylate and N-vinyl imidazole by varying monomer feeding profiles

Copolymerization is one way of influencing the properties of polymers and the outcome of copolymerization between vinyl monomers is dependent on the reactivity ratios between the monomers. Incorporation of polar monomers into copolymers offer many benefits. In this regard, N-Vinyl imidazole (NVI) carries much significance as a comonomer. NVI is a specialty monomer. The high polarity and planarity of NVI can impart many beneficial characteristics upon copolymerization with other vinyl monomers. However, its unfavourable reactivity ratios with other vinyl monomers prevent the facile incorporation of NVI in the copolymers. In this work, a semi-continuous solution polymerization is employed with the help of software called Monomer Addition Profile (MAP) to predict the optimal addition profile of the more reactive monomer (methyl methacrylate) through an iterative approach in order to achieve uniform incorporation of less reactive comonomer in the copolymer chain. The predicted chemical composition distribution (CCD) of the copolymerization is used to determine the homogeneity of copolymers which is well supported by the glass transition temperature (Tg) of copolymers. Apart from the workflow of MAP, solubility characteristics of copolymers, microstructure and sequence length are also discussed in this article.

Applications of electrochemical techniques for determination of anticoagulant drug (Rivaroxaban) in real samples

The electrochemical behavior of rivaroxaban (RIV), a direct Factor Xa inhibitor, was investigated using a glassy carbon electrode (GCE) based on molecularly imprinted polymer (MIP). The MIP was developed by co-polymerization of different monomers (acrylamide and methacrylic acid) with the cross-linker (ethylene glycol dimethacrylate (EGDMA)) in the presence of initiator (potassium persulphate) and RIV as a template. Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM), energy dispersive X-ray (EDX), and scanning electron microscope (SEM) were used for the characterization of the fabricated polymers. To prepare the potentiometric sensor, the MIP was incorporated in polyvinyl chloride (PVC) in the presence of a plasticizer and coated on the GCE as one layer. While the voltammetric sensor was prepared by drop coating technique, in which the graphene oxide and MIP were deposited on the bare GCE, respectively. Linear response over RIV concentrations in the range of 1.2 × 10−9 – 1 × 10−3 mol L−1 and 5.4 × 10−11 – 3.1 × 10−3 mol L−1 with detection limits of 2.4 × 10−10 mol L−1 and 2.3 × 10−12 mol L−1 were achieved for potentiometric and voltammetric sensors, respectively. Both sensors have high precision, selectivity, and good stability. Due to the abovementioned merits, both sensors were successfully applied for the detection of RIV in different blood samples and in pharmaceutical tablets, and acceptable mean recoveries (99.3–100.3%) were obtained.

Log Poct/SA Predicts the Thermoresponsive Behavior of P(DMA-co-RA) Statistical Copolymers

Polymers that exhibit a lower critical solution temperature (LCST) have been of great interest for various biological applications such as drug or gene delivery, controlled release systems, and biosensing. Tuning the LCST behavior through control over polymer composition (e.g., upon copolymerization of monomers with different hydrophobicity) is a widely used method, as the phase transition is greatly affected by the hydrophilic/hydrophobic balance of the copolymers. However, the lack of a general method that relates copolymer hydrophobicity to their temperature response leads to exhaustive experiments when seeking to obtain polymers with desired properties. This is particularly challenging when the target copolymers are comprised of monomers that individually form nonresponsive homopolymers, that is, only when copolymerized do they display thermoresponsive behavior. In this study, we sought to develop a predictive relationship between polymer hydrophobicity and cloud point temperature (TCP). A series of statistical copolymers were synthesized based on hydrophilic N,N-dimethyl acrylamide (DMA) and hydrophobic alkyl acrylate monomers, and their hydrophobicity was compared using surface area-normalized octanol/water partition coefficients (Log Poct/SA). Interestingly, a correlation between the Log Poct/SA of the copolymers and their TCPs was observed for the P(DMA-co-RA) copolymers, which allowed TCP prediction of a demonstrative copolymer P(DMA-co-MMA). These results highlight the strong potential of this computational tool to improve the rational design of copolymers with desired temperature responses prior to synthesis.

Poly(ionic liquid) materials tailored by carboxyl groups for the gas phase-conversion of epoxide and CO2 into cyclic carbonates

Carbon dioxide (CO2) is an important C1 resource, and the preparation of cyclocarbonate by catalyzing CO2 and epoxides is a nature-friendly route to utilize. In this study, polymer ionic liquid materials (PILMs) were prepared by copolymerizing the vinylimidazole-based ionic liquids (ILs) as monomer with carbonyl-rich copolymer monomer methyl methacrylate (MMA) and crosslinking agent ethylene glycol dimethacrylate (EGDMA), to enhance the affinity of PILMs for CO2 and PO. Then, epoxides and CO2 were converted to cyclic carbonates using PILMs by the gas-liquid reaction (GLR) and the gas phase-conversion progress (GCP). Amongst those polymer ionic liquid materials, the PILM containing carboxypropyl group (PILM-VCPImBr) exhibited the performance with the propylene carbonate (PC) yield of 96.7% (at 130 °C, 3 MPa CO2, reaction time 3 h) by GLR. And the yield of PC reached 94.2% (at 130 °C, 2 MPa CO2, reaction time 3 h) by GCP, which was the same as that of GLR. The excellent catalytic activity can be attributed to the fact that the PILMs fully dispersed the active sites and were rich in pores, which could effectively catalyze propylene oxide (PO) and CO2 to generate PC. Finally, 1H NMR spectra showed that VCPImBr and PO formed strong hydrogen bonds to participate the ring-opening process of epoxides, and a possible catalytic mechanism of H-bond synergistic effect was proposed. This article provides a novel strategy for designing both stable and nature-friendly catalysts in the CO2 transformation, and proposes a new method for cyclic carbonate conversion.

Super-Adsorptive Biodegradable Hydrogel from Simply Treated Sugarcane Bagasse.

There is a great demand for biodegradable hydrogel, and cellulose enriched wastes materials are widely used to serve this purpose for various advance applications (e.g., biomedical and environmental). Sugarcane bagasse is cellulose-enriched agro-waste, abundantly grown in Bangladesh. This study aimed to treat sugarcane bagasse-based agro-waste using a sustainable and ecofriendly approach to produce hydrogel with super-swelling capacity for adsorption of copper, chromium, iron ions, methylene blue and drimaren red dyes. To increase the swelling property of hydrogels, copolymerization of hydrophilic monomers is an effective technique. Therefore, this study aimed to prepare hydrogel via free radical graft-copolymerization reaction among acrylamide, methyl methacrylate and treated bagasse in the presence of N,N-methylene-bis-acrylamide as a crosslinker and potassium persulphate as an initiator. To obtain maximum yield, reaction conditions were optimized. It was found that hydrogel obtained from chemically treated sugarcane bagasse showed maximum water absorption capacity of 228.0 g/g, whereas untreated bagassebased hydrogel could absorb ~50 g/g of water. Maximum adsorption capacity of 247.0 mg/g was found for copper ion. In addition, organic pollutant removal from industrial effluent also showed good performance, removing >90% of methylene blue and 62% of drimaren red dye, with shorter kinetics. The biodegradability study showed that after 90 days of exposure, the hydrogels degraded to about 43% of their own mass. Therefore, the produced hydrogel could be an alternative adsorbent to remove pollutants and also for other potential applications.

EDTA Modified Hollow Microporous Organic Nanospheres for Enhancing Adsorption of Metal Ions

AbstractIn this study, ethylenediaminetetraacetic acid (EDTA) modified hollow microporous organic nanospheres (EDTA‐HMONs‐BA) were prepared by a combination of one‐pot hyper‐crosslinking mediated self‐assembly using polylactide‐b‐polystyrene (PLA‐b‐PS) diblock copolymer and benzylamine (BA) monomers as precursors and subsequent post‐modification with EDTA. The obtained EDTA‐HMONs‐BA were characterized by FT‐IR, TEM, TGA, solid state 13C NMR, N2 adsorption‐desorption test et al. It revealed that the EDTA‐HMONs‐BA have a high specific surface area (226.86 m2 g−1), which exhibited excellent adsorption ability for Cu2+ ions (236 mg g−1) with adsorption characteristics of pseudo‐second‐order model and Langmuir isotherm equation. Moreover, the obtained adsorbent is of high stability after five consecutive cycles. Besides, EDTA‐HMONs‐BA also showed good adsorption capacities for hard acid metal ions (Cr3+), soft acid metal ions (Ag+, Cd2+), borderline acid metal ions (Cu2+, Ni2+, Zn2+). The above results indicated that the EDTA‐HMONs‐BA can be considered as potential adsorbents for the removal of heavy‐metal ions owing to the easily accessible adsorption sites and sufficiently good stability.

Material Properties of Functional Polyethylenes from Transition-Metal-Catalyzed Ethylene–Polar Monomer Copolymerization

Material Properties of Functional Polyethylenes from Transition-Metal-Catalyzed Ethylene–Polar Monomer Copolymerization

Influence of Chain Length of Gradient and Block Copoly(2-oxazoline)s on Self-Assembly and Drug Encapsulation.

Amphiphilic gradient copolymers represent a promising alternative to extensively used block copolymers due to their facile one-step synthesis by statistical copolymerization of monomers of different reactivity. Herein, an in-depth analysis is provided of micelles based on amphiphilic gradient poly(2-oxazoline)s with different chain lengths to evaluate their potential for micellar drug delivery systems and compare them to the analogous diblock copolymer micelles. Size, morphology, and stability of self-assembled nanoparticles, loading of hydrophobic drug curcumin, as well as cytotoxicities of the prepared nanoformulations are examined using copoly(2-oxazoline)s with varying chain lengths and comonomer ratios. In addition to several interesting differences between the two copolymer architecture classes, such as more compact self-assembled structures with faster exchange dynamics for the gradient copolymers, it is concluded that gradient copolymers provide stable curcumin nanoformulations with comparable drug loadings to block copolymer systems and benefit from more straightforward copolymer synthesis. The study demonstrates the potential of amphiphilic gradient copolymers as a versatile platform for the synthesis of new polymer therapeutics.

Multivariate Linear Regression Models to Predict Monomer Poisoning Effect in Ethylene/Polar Monomer Copolymerization Catalyzed by Late Transition Metals

This study combined density functional theory (DFT) calculations and multivariate linear regression (MLR) to analyze the monomer poisoning effect in ethylene/polar monomer copolymerization catalyzed by the Brookhart-type catalysts. The calculation results showed that the poisoning effect of polar monomers with relatively electron-deficient functional groups is weaker, such as ethers, and halogens. On the contrary, polar monomers with electron-rich functional groups (carbonyl, carboxyl, and acyl groups) exert a stronger poisoning effect. In addition, three descriptors that significantly affect the poisoning effect have been proposed on the basis of the multiple linear regression model, viz., the chemical shift of the vinyl carbon atom and heteroatom of polar monomer as well as the metal-X distance in the σ-coordination structure. It is expected that these models could guide the development of efficient catalytic copolymerization system in this field.

Preparation of size controllable polymer fluorescent microspheres by self-stabilized precipitation polymerization

ABSTRACT In contrast to small fluorescent molecules, fluorescent microspheres are easier to be modified and more stable. In this work, a novel fluorescent microsphere was obtained by ternary copolymerisation of maleic anhydride (MAn), vinyl acetate (VAc) and fluorescent monomer containing Rhodamine B group (FM-Rh B). The morphology, structure, composition and fluorescent performances of the fluorescent microspheres were characterised by scanning electron microscope, Fourier transform infrared spectrometer, UV–vis spectrophotometer, and fluorescence spectroscope. The results show that the surface of the fluorescent microspheres was smooth and free of impurities, which are conducive to its application in the fields of biology and medicine. The microspheres display good fluorescence properties under both blue and green light, which expands the application of these microspheres. It can emit strong fluorescence at 566 nm even in polar solvents. The size of the fluorescent microspheres is in the range of 184–1022 nm and can be controlled by changing polymerisation conditions.

Comparable Studies on Nanoscale Antibacterial Polymer Coatings Based on Different Coating Procedures.

The antibacterial activity of different antibiotic and metal-free thin polymer coatings was investigated. The films comprised quaternary ammonium compounds (QAC) based on a vinyl benzyl chloride (VBC) building block. Two monomeric QAC of different alkyl chain lengths were prepared, and then polymerized by two different polymerization processes to apply them onto Ti surfaces. At first, the polymeric layer was generated directly on the surface by atom transfer radical polymerization (ATRP). For comparison purposes, in a classical route a copolymerization of the QAC-containing monomers with a metal adhesion mediating phosphonate (VBPOH) monomers was carried out and the Ti surfaces were coated via drop coating. The different coatings were characterized by X-ray photoelectron spectroscopy (XPS) illustrating a thickness in the nanomolecular range. The cytocompatibility in vitro was confirmed by both live/dead and WST-1 assay. The antimicrobial activity was evaluated by two different assays (CFU and BTG, resp.,), showing for both coating processes similar results to kill bacteria on contact. These antibacterial coatings present a simple method to protect metallic devices against microbial contamination.

Modulating Boronic Ester Stability in Block Copolymer Micelles via the Neighbor Effect of Copolymerized Tertiary Amines for Controlled Release of Polyphenolic Drugs.

The traceless and pH-sensitive properties of boronic esters are attractive for the synthesis of polymer-drug conjugates, but current platforms suffer from both low stability under physiologically relevant conditions and synthetically demanding optimization to tune drug release profiles. We hypothesized that the high catechol affinity and stability of Wulff-type boronic acids could be mimicked by copolymerization of phenyl boronic acid with a tertiary amine and subsequent micellization. This strategy yielded a versatile platform for the preparation of reversible polymer-drug conjugates, which more than doubled the oxidative stability of encapsulated polyphenolic drug cargo at physiologically relevant pH and enabled simple and incremental tuning of drug release kinetics. Moreover, we validated, with 19F NMR, that these copolymers exhibit uniquely high catechol affinity that could not be replicated by combinations of similarly functionalized small molecules. Overall, this report demonstrates that copolymerization of boronic acid and tertiary amine monomers is a powerful and modular approach to improving boronic ester chemistry for drug delivery applications.