2‐Mercapto thioxanthone as a chain transfer agent in free‐radical polymerization: A versatile route to incorporate thioxanthone moieties into polymer chain‐ends

2‐Mercapto thioxanthone (TX‐SH) was used as a chain transfer agent in free‐radical polymerization of methyl methacrylate (MMA) and styrene (St), by using 2,2′‐azobisisobutyronitrile (AIBN) as an initiator at 70°C. Chain transfer constants were found to be 1.41 and 0.12 for St and MMA, respectively. The use of TX‐SH as a chain transfer agent leads to the formation of polymers with thioxanthone (TX) end groups. The incorporation TX moiety was confirmed by spectral measurements. Polymers obtained this way were used as triplet photosensitizer in free‐radical polymerization of MMA in the presence of a hydrogen donor such as N‐methyldiethanolamine (MDEA). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3766–3770, 2007     

Comb‐like polymer with sulfo groups and its dispersion and rheological properties in aqueous ceramic suspensions

Two types of new comb‐like polymers were formed as dispersants for aqueous ceramic suspensions with isoprenyloxy poly(ethylene glycol ether), acrylic acid, maleic anhydride as the main starting materials. During the synthesis, one comb‐like polymer introduced sodium methylallyl sulfonate (SMAS) into the reaction media, whereas the other did not. The chemical structure and molecular weight were characterized by Fourier transform infrared spectroscopy and gel permeation chromatography. The effects of the polymers on the dispersion, ζ potential and rheological properties of the kaolin suspensions are discussed in detail. The results indicate that SMAS facilitated chain transfer, controlled the effective charge density of the surface, and increased the electrostatic repulsion force. The kaolin suspensions displayed shear‐thinning behavior on the basis of the electrostatic and steric effects of the comb‐like polymers. The apparent viscosity decreased from 1088 to 258 mPa s with the assistance of the SMAS‐prepared comb‐like polymer as a dispersant. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44563.     

Functionalized polymeric silver nanoparticle hybrid network as a dual antimicrobe: Synthesis,characterization, and antibacterial application

The present work describes a novel method for the synthesis of silver polymer nanocomposite for the delivery of amoxicillin (AMO). Silver nanoparticles (AgNPs) were synthesized with chitosan and silver nitrate. The reaction parameters were optimized. Three‐dimensional polymeric networks were synthesized by simple free‐radical graft copolymerization. UV–visible spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, SEM, atomic force microscopy, dynamic light scattering, and zeta potential analysis were used for the complete characterization of the samples. Swelling studies and swelling factors were evaluated. In vitro release of AMO and AgNPs at physiological pHs was analyzed using the Peppas kinetic model to explain the drug delivery mechanism. Cytotoxicity, free‐radical scavenging, and antibacterial activities were analyzed. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43479.     

Hydroxybisphosphonate‐containing polymeric drug‐delivery systems designed for targeting into bone tissue

The preparation and characterization of a novel polymeric drug‐delivery system designed for bone targeting of antineoplastics is described. The system was based on biocompatible poly[N‐(2‐hydroxypropyl)methacrylamide] carrier containing hydroxybisphosphonate targeting moieties and the model radiotherapeutics ¹²⁵I or ¹¹¹In or the anticancer drug doxorubicin. The in vitro binding studies with hydroxyapatite as a bone model proved that the system was efficiently adsorbed on this mineral. The systems contained model drugs bound by stable (amide), hydrolytically cleavable (hydrazone) or enzymatically cleavable (Gly‐Phe‐Leu‐Gly tetrapeptide) spacers. It was proven in vitro that, in the case of cleavable spacers, the drug could be released from the polymer carrier at a rate depending on the pH or enzymatic stimulus. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci: 3192–3201, 2006     

Method for the determination of primary,secondary, and tertiary amino groups in star‐shaped polyamide 12 with a poly(ethylene imine) core

A star‐branched poly(ethylene imine)‐g‐polyamide 12 with a high concentration of primary amino end groups is an object of interest for future chemical modifications. In many cases, the concentration of primary amino groups, which are also the end groups of the polyamide 12 arms, and the concentrations of secondary and tertiary amino groups in a sample need to be known independently. Because of the difference in the reactivity of phthalic acid toward amino groups, its reaction with poly(ethylene imine)‐g‐polyamide 12 can be used for the analytical determination of these groups. With primary amino groups, phthalic acid forms phthalimido moieties, which are detectable by IR spectroscopy. The IR bands can be used for quantitative analysis with an appropriate calibration procedure. The concentration of primary amino groups can also be calculated as the difference between the concentration of all types of amino groups before the reaction with phthalic acid and the final concentration of amino and carboxylic groups after the reaction. The final concentration of the amino groups is equal to the concentration of unreacted tertiary amino groups after the reaction with phthalic acid anhydride. The difference between the final concentration of carboxylic groups and the initial concentration of carboxylic groups is equivalent to the concentration of secondary amino groups, which react with phthalic acid to form phthalamido acid moieties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 556–563, 2005     

Acrylonitrile copolymers containing guanidine oligomer: Synthesis and use for the preparation of nonleaching antimicrobial acrylic fibers

Nonleaching acrylic fibers with permanent antibacterial activity were prepared via a combination of copolymerization and a wet‐blend‐spinning method. Specifically, poly[acrylonitrile‐co‐modified poly(hexamethylene guanidine hydrochloride)] [poly(AN‐co‐M‐PHMG)] copolymers containing a covalently connected antibacterial guanidine oligomer were first synthesized via the precipitation copolymerization of acrylonitrile (AN) with a modified poly(hexamethylene guanidine hydrochloride) (M‐PHMG) macromonomer in water. Then, modified acrylic fibers were prepared from a mixture of the copolymer and commercial fiber‐grade AN terpolymer via a wet‐spinning process with dimethyl sulfoxide as the solvent. The influences of the reaction time, temperature, pH value of the medium, and amount of initiator on the copolymerization and the effect of the copolymer content on the mechanical properties and antibacterial activity of the modified acrylic fibers were investigated in detail. The results show that the M‐PHMG macromonomer exhibited a lower reactivity than AN. The poly(AN‐co‐M‐PHMG) copolymer with a PHMG content of 5.49% and an intrinsic viscosity of 11.2 dL/g could be synthesized under optimized conditions. With increasing copolymer content, the tensile strength of the modified acrylic fibers decreased slightly, and the antibacterial activity increased. The modified acrylic fibers with a copolymer content of 50% (i.e., a PHMG content of 2.75%) exhibited both good mechanical properties and excellent antibacterial activity. The additional antibacterial function would surely enlarge the applications of the fiber. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Dendritic polyamines: simple access to new materials with defined treelike structures for application in nonviral gene delivery

Polycationic dendrimers are interesting nonviral vectors for in vitro DNA delivery. We describe a simple approach to the synthesis of dendritic polyamines with different molecular weights and adjustable flexibility (degrees of branching; DB). Both parameters influence the transfection efficiency and the cell toxicity of the polymer. Functionalization of hyperbranched polyethylenimine (PEI) by a two-step procedure generated fully branched pseudodendrimers (analogues of polypropylenimine (PPI) and polyamidoamine (PAMAM) dendrimers). The DNA transfection efficiencies observed for these polymers depended on the cell line investigated. The highest efficiencies were observed for polymers whose unfunctionalized PEI cores had molecular weights in the range M(w)=6000-25 000 g mol(-1). The cytotoxicity of the dendrimers generally rises with increasing core size. The data collected for NIH/3T3 and COS-7 cells indicate a maximum transfection efficiency at around 60 % branching for the PPI analogues, and at a PEI-core molecular weight of M(w)=25 000 g mol(-1). PAMAM functionalization of PEI (M(w)=5000 and 21 000 g mol(-1)) leads to polymers with little or no cytotoxity in the cell lines investigated.     

Polyamide4‐block‐poly(vinyl acetate) via a polyamide4 azo macromolecular initiator: Thermal and mechanical behavior,biodegradation, and morphology

A series of polyamide4‐block‐poly(vinyl acetate)s were synthesized by the radical polymerization of vinyl acetate (VAc) using an azo macromolecular initiator composed of polyamide4 (PA4). The block copolymers were investigated by examining their molecular weight, structure, thermal and mechanical properties, biodegradation, and the morphology of the film surface. The compositions and molecular weights (Mw) ranging from 46,800 to 163,700 g mol^?1 of the block copolymers varied linearly with increasing molar ratio of VAc to azo‐PA4. The block copolymers have high melting points of 248.2–262.5°C owing to PA4 blocks and heats of fusion, which were linearly dependent on the PA4 content. The mechanical properties of the block copolymers were monotonically dependent on the composition, i.e., increasing the PA4 content increased the tensile strength, whereas increasing the poly(vinyl acetate) content increased the elongation at break. The morphology of the block copolymers suggested the appearance of microphase separation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42466.     

Plasma‐brominated cyclo‐olefin polymer slides: Suitable macroinitiators for activator regenerated by electron transfer/atom radical transfer polymerization

Activators regenerated by electron transfer–atom radical transfer polymerization (ATRP) as a controlled living polymerization are distinguished by their acceptance of small amounts of transition‐metal complexes and oxygen and by their tolerance of reducing agents at a high concentration. The precondition of all ATRP applications is the use of homolytic or heterolytic cleavable halides as a dormant species; this allows the propagation of monomer chains. Hence, alkyl bromides are slightly cleavable and are the preferred initiators for ATRP. The bromination of polymer slides used as macroinitiators was carried out under gentle bromoform plasma conditions. This led to an oxidation‐resistant stable bromine layer. More than 20 bromines per 100 carbons on the polymer scaffold were permanently bound to the substrate after plasma treatment. The resulting amounts of secondary and tertiary bromines on the polymer scaffold exhibited a suitable macroinitiator concentration for the surface‐initiated polymerization of methyl methacrylate and glycidyl methacrylate. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40662.     

Highly efficient adsorbent for organic dyes based on a temperature‐ and pH‐responsive multiblock polymer

The self‐assembly behavior of amphiphilic block copolymers in selective solutions has many applications in environmentally responsive polymer materials. In this article, we report on a new amphiphilic, temperature and pH dual‐responsive poly[2‐dimethylaminoethyl methacrylate‐co‐(methyl methacrylate)]‐b‐poly[poly(ethylene glycol) methacrylate] [P(DMAEMA‐co‐MMA)‐b‐PPEGMA], which was synthesized via reversible addition–fragmentation chain‐transfer polymerization. The structure, self‐assembly behaviors, and process of organic dye adsorption were characterized by ¹H‐NMR, ultraviolet–visible absorbance spectroscopy, and DLS measurements. P(DMAEMA‐co‐MMA)‐b‐PPEGMA was proven to be an outstanding adsorbent with excellent reversibility. Methyl red was released from the micelles as the pH value of the solution was adjusted to 4, and it could also be encapsulated again when the pH value was adjusted to 7.4 because of the sensitive pH‐responsive ability. It is promising that the triblock polymer had a positive effect on dye adsorption for environmental protection. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46626.     

Synthesis and characterization of a surface imprinting silica gel polymer functionalized with phosphonic acid groups for selective adsorption of Fe(III) from aqueous solution

A Fe(III) ion‐imprinted silica gel polymer functionalized with phosphonic acid groups (IIP‐PA/SiO₂) was prepared with surface imprinting technique by using Fe(III) ion as template ion, grafted silica gel as support, and vinylphosphonic acid as functional monomer. The polymer was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller, and thermogravimetric analysis. The synthesized imprinted silica gel polymer was used as a sorbent for Fe(III) adsorption. The adsorption properties, such as the effect of solution pH, adsorption kinetic, adsorption isotherm, adsorption selectivity as well as the regeneration of sorbent were studied. The results showd that the prepared sorbent (IIP‐PA/SiO₂) had a short adsorption equilibrium time (12 min) and high adsorption capacity (29.92 mg g^?1) for Fe(III) at the optimal pH of 2.0. The selectivity coefficients of the sorbent for Fe(III) in presence of Cr(III), M_n (II), and Zn(II) were 51.76, 27.86, and 207. 76, respectively. Moreover, the adsorption capacity of the prepared sorbent did not decrease significantly after six repeated use. Thus, the prepared ion‐imprinted silica gel polymer was a promising candidate sorbent for the selective adsorption of Fe(III) from aqueous solutions. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45165.     

Nafion modified with simple bases and amino acid derivatives: Survey of physical properties and search for effective pervaporation membranes

Nafion, a solid perfluorinated polymeric sulfonic acid, reacts readily with bases and can thus be converted to a tremendous number of individual modifications. A survey of spectral, mechanical, thermal, and pervaporation characteristics of Nafion modified with simple inorganic and organic bases and with the derivatives of amino acids is thus reported. The spectral characteristics, thermal stability, and T_g changed pronouncedly for Nafion modified with the stronger bases, such as ammonium or tris(hydroxymethyl)aminomethane, while minor changes were observed for Nafion modified with the derivatives of amino acids. Permeability and selectivity of Nafion observed for the pervaporation of methanol–dimethyl carbonate and methanol–methyl acetate mixtures were mainly influenced by the modification with amines bearing hydroxyl and, most pronouncedly, sulfo groups. Importantly, the pervaporation membrane from Nafion modified with taurine appeared similarly permeable and hygroscopic but more methanol-selective than that from pure Nafion.     

Poly(methyl vinyl ether‐alt‐maleic anhydride) functionalized with 3‐aminophenylboronic acid: A new boronic acid polymer for sensing diols in neutral water

Amidation of poly(methyl vinyl ether‐alt‐maleic anhydride) with 3‐aminophenylboronic acid was used to prepare a new boronic acid polymer. The binding of catechol dye, Alizarin Red S to the polymer obtained resulted in getting a stable, colored sensor which was used to establish association constants with different diols in competitive assay. The binding of different diols was readily detected by color change and absorbance values measured at 450 nm were used to calculate the association constants. The polymer obtained formed high‐affinity complexes with ribonucleosides, particularly cytidine and uridine. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40778.     

Poly(allyl glycidyl ether)‐block‐poly(ethylene oxide): A novel promising polymeric intermediate for the preparation of micellar drug delivery systems

Novel diblock copolymers designed for the preparation of micellar drug delivery systems, consisting of hydrophobic poly(allyl glycidyl ether) (PAGE) and hydrophilic poly(ethylene oxide) (PEO), were prepared, and their self‐assembly into micellar structures was studied. Copolymers differing in the length of the polymer blocks were purified and characterized. These amphiphilic copolymers with narrow molecular weight distributions were prepared through the anionic polymerization of allyl glycidyl ether with PEO monomethyl ether sodium salt as the macroinitiator. The PAGE–PEO copolymer readily formed small micelles with narrow size distributions via simple dissolution in water. The addition of pendant double bonds to the hydrophobic part of the chain was intended for further covalent modifications. Catalytic hydrogenation, the radical crosslinking of the micelle core, and the addition of thiol to double bonds of the copolymer were examples of such modifications that were proved to proceed with a quantitative yield for this copolymer. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 201–211, 2005     

Guanidinylation: A simple way to fabricate cell penetrating peptide analogue‐modified chitosan vector for enhanced gene delivery

In view of the analogous transmembrane function to cell penetrating peptides, guanidine group was incorporated into chitosan by chemical modification to enhance the transfection performance of chitosan vectors. Guanidinylated chitosan (GCS) was shown to be well soluble in neutral aqueous solution. The interaction between GCS with plasmid DNA was characterized by agarose retardation experiment and ethidium bromide displacement assay. GCS formed more stable complexes with DNA under physiological pH than chitosan. The transfection efficiency of GCS was evaluated employing COS‐7 cell line—GCS polyplexes demonstrated higher transfection efficiency and lower cytotoxicity relative to chitosan. The optimum efficiency of GCS was achieved in the vicinity of the critical complexing ratio. The results of flow cytometry indicated that guanidinylation promoted an eightfold increase in the cell uptake. The study revealed that guanidinylated chitosan is a promising candidate as an effective nonviral vector for in vivo gene delivery. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preparation of a new molecularly imprinted polymer based on self‐crosslinkable cellulose acrylate in aqueous solution: A drug delivery system for furosemide

In the present study, a new, green, and biodegradable molecularly imprinted polymer (MIP) based on modified cellulose is introduced for the drug furosemide. First, microcrystalline cellulose was converted into cellulose acrylate (CA). Then the prepared CA underwent self‐crosslinking in the drug preassembly solution. The preassembly solution of the drug was also prepared using furosemide as the template molecule and acrylamide as the functional monomer in an aqueous medium. The results obtained from the binding and selectivity studies indicate the successful preparation of the CA‐based MIP (CA‐MIP) in aqueous solution. In the final step, an in vitro release study of furosemide from the synthesized polymers was carried out in a pH = 7.41 phosphate‐buffered saline solution at 37 °C. The drug release profiles showed that the release rate of the CA‐MIP is more controlled than that of the corresponding nonimprinted polymer, especially at the early stages of release. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45581.     

A highly oriented poly(3,4‐ethylenedioxythiophene) film: Facile synthesis and application for supercapacitor

A single crystal poly(3,4‐ethylenedioxythiophene) (PEDOT) film with highly oriented arrangement has been fabricated from an aqueous solution by a novel unipolar pulse electropolymerization method. Film formation mechanism was proposed based on the in situ mass change during electropolymerization process measured by the electrochemical quartz crystal microbalance. The compositions, morphology and crystal structure of the fabricated films are characterized by Fourier transfer infrared spectroscopy, scanning electron microscopy, and X‐ray diffraction, respectively. It is found that the prepared PEDOT film on carbon nanotubes (CNTs)‐modified electrode with a spongy dendritic structure possesses outstanding electroactivity, high specific capacitances (239.1 F?g^?1, including the specific capacitances of CNTs which is 21.4 F?g^?1), and excellent cycling stability with 7.3% decay from its initial capacitance over 10,000 cycles. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43418.