Selective etching of polylactic acid in poly(styrene)‐block‐poly(d,l)lactide diblock copolymer for nanoscale patterning

Self‐assembled thin films of a lamellar forming polystyrene‐block‐poly(d,l )lactide (PS‐b‐PLA) block copolymer (BCP) contain a “reactive” block that can be readily removed to provide a template for substrate pattern formation. Various methods of PLA removal were studied here with a view to develop the system as an on‐chip etch mask for substrate patterning. Solvo‐microwave annealing was used to induce microphase separation in PS‐b‐PLA BCP with a periodicity of 34 nm (L_o) on silicon and silicon on insulator (SOI) substrates. Wet etches based on alkaline and enzymatic solutions were studied in depth. Fourier transform‐infrared (FT‐IR) analysis showed that basic hydrolysis using sodium hydroxide (NaOH) or ammonium hydroxide (NH₄OH) solutions resulted in greater PLA removal in comparison to an enzymatic approach using Proteinase K in a Tris‐HCl buffer solution. However, in the enzymatic approach, the characteristic self‐assembled fingerprint patterns were retained with less damage. Comparison to a dry etch procedure using a reactive ion etch (RIE) technique was made. A detailed study of the etch rate of PS and PLA homopolymer and PS‐b‐PLA shows depending on DC bias, the etch selectivity of PLA and PS can be almost doubled from 1.7 at DC bias 145 V to 3 at DC bias 270 V. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40798. Together with Krebs et al., J. Appl. Polym. Sci. (2014) 131 , 40795, doi: 10.1002/app.40795 , this article is part of a Special Issue on Polymers for Microelectronics. The remaining articles appear in J. Appl. Polym. Sci. (2014) volume 131 , issue 24. This note was added on 1st July 2014.     

Functional modification of poly(vinyl alcohol) by copolymerizing with a hydrophobic cationic double alkyl‐substituted monomer

In this paper, a hydrophobic monomer (HM) that has a cationic double alkyl‐substituted group bonded to the nitrogen atom was first synthesized. Then a hydrophobic poly(vinyl alcohol) (PVA) was prepared by a radical solution copolymerization of vinyl acetate (VAc) with the HM followed by an alcoholysis reaction in alkaline conditions. The structures of HM and hydrophobically modified PVA (H‐PVA) were confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The effect of hydrophobic cationic segments on crystallization behaviors, mechanical properties, morphology, solution viscosity, and hydrophobic property were investigated. The results indicated that the crystallinity decreased from 37.2% of pure PVA to the minimum 23.2% of H‐PVA with the incorporation of 1.15 mol % HM. The thermal decomposition temperature of H‐PVA increased by about 50 °C compared with that of pure PVA. The viscosity of the H‐PVA solution was several times higher than that of the corresponding unmodified PVA solution over the whole shear rate range, which demonstrated that the H‐PVA had good shear‐resistance ability. Furthermore, the contact angle was significantly increased from 55.1° to 115° with the incorporation of only 0.83% HM, which illustrated that the H‐PVA had high hydrophobicity. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43888.     

Thermoresponsive and biocompatible poly(vinyl alcohol)‐graft‐poly(N,N‐diethylacrylamide) copolymer: Microwave‐assisted synthesis,characterization, and swelling behavior

Novel thermoresponsive poly(vinyl alcohol)‐graft‐poly(N,N‐diethylacrylamide) (PVA‐g‐PDEAAm) copolymers were prepared by microwave‐assisted graft copolymerization using a potassium persulfate/N,N,N′,N′‐tetramethylethylenediamine (KPS/TEMED) initiator system. The structures of PVA‐g‐PDEAAm copolymers were characterized by ¹H‐NMR, Fourier transform infrared spectroscopy, differential scanning calorimetry/thermogravimetric analysis, gel permeation chromatography, X‐ray diffraction, and scanning electron microscopy. The effects of various process parameters on grafting were systematically studied: microwave power, KPS, monomer and PVA concentrations, and ultraviolet irradiation. Under optimal conditions, the maximum grafting percent and graft efficiency were 101% and 93%, respectively. Furthermore, a lower critical temperature of copolymers was measured in the range 29–31 °C by ultraviolet spectroscopy. The swelling behavior of graft membranes was carried out at various temperatures, and the results showed that the swelling behavior of membranes was dependent on the temperature. In vitro cell culture studies using L929 fibroblast cells confirmed cell compatibility with the PVA‐g‐PDEAAm copolymer and its membrane, making them an attractive candidate for drug delivery systems. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45969.     

Tetrahydrosalen‐stabilized,chloride‐containing rare‐earth complexes: Facile initiator precursors for the preparation of hydroxytelechelic poly(ε‐caprolactone)s

End‐capped poly(ε‐caprolactone)s (PCLs) have been prepared elsewhere by various initiators. However, hydroxytelechelic PCLs have been reported less frequently, although there are two hydroxyl end groups in one polymer chain, which allows diversified functionalization. Two tetrahydrosalen‐backboned chlorides containing rare‐earth complexes, YbLCl(DME)₂ and ErLCl(DME) {where L is 6,6′‐[ethane‐1,2‐diylbis(methylazanediyl)]bis (methylene)bis(2,4‐di‐tert‐butylphenol) and DME is dimethoxyethane}, were first synthesized in this study, and they were used as initiator precursors for a ring‐opening polymerization in the presence of NaBH₄ to afford hydroxytelechelic PCLs. The polymerization under different conditions was investigated, and a possible mechanism is proposed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis and characterization of lignin–poly(acrylamide)–poly(2‐methacryloyloxyethyl) trimethyl ammonium chloride copolymer

In this work, two monomers, acrylamide (AM) and [2‐(methacryloyloxy)ethyl]trimethylammonium chloride (DMC) were copolymerized from kraft lignin (KL) in an aqueous suspension initiated by free radical copolymerization in the presence of potassium persulfate. The impact of copolymerization conditions on the charge density and molecular weight of the copolymers was investigated. The molecular weight and mass balance analyses confirmed that the homopolymer [polyDMC (PDMC) and polyAM (PAM)] and undesired copolymer (AM–DMC) productions dominated as time, initiator, and DMC dosage increased more than the optimum values. The activation energy of the polymerization of KL and AM (43.02 kJ mol^?1), KL and DMC (21.99 kJ mol^?1), AM (14.54 kJ mol^?1), DMC (10.34 kJ mol^?1), and AM and DMC (18.13 kJ mol^?1) was determined. Proton nuclear magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, and elemental analysis confirmed the production of KL–AM–DMC copolymer. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46338.     

Preparation and release characteristics of dexamethasone acetate loaded organochlorine‐free poly(lactide‐co‐glycolide) nanoparticles

Dexamethasone‐loaded poly(lactide‐co‐glycolide) (PLGA) devices are commonly used as model systems for controlled release. In this study, PLGA nanoparticles containing dexamethasone acetate were prepared by a nanoprecipitation technique in the absence of organochlorine solvents and were characterized by their mean size, ζ potential, scanning electron microscopy, and differential scanning calorimetry to develop a controlled release system. The analytical method for the quantification of dexamethasone acetate by high‐performance liquid chromatography was validated. The results show that it was possible to prepare particles at a nanometric size because the average diameter of the drug‐loaded PLGA particles was 540 ± 4 nm with a polydispersity index of 0.07 ± 0.01 and a ζ potential of ?2.5 ± 0.3 mV. These values remained stable for at least 7 months. The drug encapsulation efficiency was 48%. In vitro tests showed that about 25% of the drug was released in 48 h. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41199.     

Synthesis and properties of biodegradable supramolecular polymers based on polylactide‐block‐poly(δ‐valerolactone)‐block‐polylactide triblock copolymers

Biodegradable supramolecular polymers (SMPs) were synthesized by the end‐functionalization of polylactide‐block‐poly(δ‐valerolactone)‐block‐polylactide (PLA–PVL–PLA) triblock copolymers with 2‐ureido‐4[1H]‐pyrimidinone (UPy) self‐complementary quadruple hydrogen‐bonding units. The end‐functionalized PLA–PVL–PLA copolymers exhibit the typical characteristics of thermoplastic elastomers. Thermal properties, crystallization behavior, crystalline structure and other properties of SMPs can be adjusted by changing the length and stereostructure of PLA blocks. The UPy groups retard the crystallization of PLA and PVL blocks, and the crystallization of PVL blocks is also depressed with increasing PLA blocks. Tensile testing reveals that the prepared SMPs present excellent mechanical properties, and dynamic mechanical analysis indicates that the heat resistance of l ‐SMPs is better than that of d ,l ‐SMPs. Shape memory property of SMPs was also studied, and the recovery ratio of SMPs with PDLLA blocks can reach 100%. The recovery ratio of l ‐SMPs is depressed as the crystallizable PLLA blocks increase. This study has systemically investigated the effect of the composition, stereostructure and crystallizability of PLA blocks on the properties of SMPs, which would provide potential approaches for the synthesis of biodegradable SMPs with tunable properties. © 2017 Society of Chemical Industry     

Preparation and characterizations of superparamagnetic iron oxide‐embedded poly(2‐hydroxyethyl methacrylate) nanocarriers

The present study aims at formulating a novel multifunctional biocompatible superparamagnetic nanoparticles carrier system with homogeneously dispersed magnetic material in solid polymer matrix of poly(2‐hydroxyethyl methacrylate) (PHEMA). The nanocomposites were designed by modified suspension polymerization of 2‐hydroxyethyl methacrylate followed by in situ coprecipitation of iron oxide inside the nanoparticle matrix yielding magnetic PHEMA (mPHEMA) nanocomposites. The so prepared nanocomposites were characterized by Fourier transform Infrared spectroscopy, X‐ray diffraction technique, Raman spectroscopy, electron diffraction, and energy‐dispersive X‐ray spectroscopy confirming the presence of Fe₃O₄ inside the PHEMA nanoparticles. The magnetization studies of nanocomposites conducted at room temperature using vibrating sample magnetometer suggested for their superparamagnetic nature having saturation magnetization (Ms) of 20 emu/g at applied magnetic field of 5 kOe. Transmission electron microscopy, field‐emission scanning electron microscopy, and dynamic light scattering/zeta potential measurements were also performed which revealed that size of mPHEMA nanocomposites was lying in the range of 60–300 nm having zeta potential of ?93 mV. The nanocomposites showed no toxicity as revealed by cytotoxicity test performed on L‐929 fibroblast by extract method. The results indicated that the prepared superparamagnetic mPHEMA nanocomposites have enormous potential to provide a possible option for magnetically assisted targeted delivery of anticancer drugs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40791.     

Synthesis of poly(butyl acrylate)‐poly(methyl methacrylate) core–shell nanomaterials of anti‐crease‐whitening properties

Core–shell nanomaterials of poly(butyl acrylate)‐poly(methyl methacrylate) were synthesized using a differential microemulsion polymerization method for being used as polyacrylate‐based optical materials, which meet the requirement of anti‐crease‐whitening and proper mechanical strength. The effects of reaction temperature and surfactant amount on the particle sizes, as well as the effect of reaction temperature on the conversion and solid content were investigated to reveal the dependence of the application properties on the reaction conditions. The spherical morphology of core–shell nanoparticles was also studied via transmission electron microscopy. The resulting polymers with a core–shell monomer ratio of butyl acrylate/methyl methacrylate at 32/10 (vol/vol) demonstrated the optimal balanced properties in the anti‐crease‐whitening and mechanical property, confirmed by the visible light transmittance measurement and the dynamic analysis of the viscoelastic properties of the synthesized core–shell nanomaterials. The smaller the particle size, the better the transparency of the resulting polymer films. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39991.     

Synthesis,characterization, flocculation,and rheological characteristics of hydrolyzed and unhydrolyzed polyacrylamide‐grafted poly(vinyl alcohol)

Graft copolymers of poly(vinyl alcohol) and polyacrylamide (PVA‐g‐PAM) were synthesized using a ceric ion–induced solution polymerization technique at 28°C. Three grades of graft copolymers were synthesized with varying acrylamide concentrations. Three grades of hydrolyzed products of PVA‐g‐PAM were synthesized with varying concentrations of sodium hydroxide solution. Hydrolyzed and unhydrolyzed PVA‐g‐PAM were characterized by viscometry, X‐ray diffractometry, infrared spectroscopy, and thermal analysis. Rheological investigation was also carried out on the aqueous solutions of various samples. The flocculation characteristics of various materials were investigated by the use of jar and settling tests in 0.25 and 5 wt %, respectively, using kaolin and iron ore suspensions. Among the series of graft copolymers, the one with fewest but longest PAM chains showed superior performance. The flocculation characteristics of the best‐performing graft copolymer were compared with those of various commercially available flocculants in the two suspensions under investigation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2109–2122, 2006     

Reactive compatibilization of poly(methyl acrylate‐ran‐acrylonitrile)/poly(ethylene) blends through amine–anhydride coupling

Methyl acrylate/acrylonitrile copolymers (MA/AN) were reactively compatibilized as the dispersed phase into poly(ethylene) (PE) for potential hydrocarbon barrier materials. The MA/AN was made reactive by including p‐aminostyrene (PAS), yielding terpolymers (MA/AN/PAS) with pendant primary amine functionality (number average molecular weight = 65–133 kg mol^?1, dispersity (?)=1.83–2.53, molar composition of PAS in copolymer F_PAS = 0.03–0.14, molar composition of AN = F_AN = 0.27–0.52). The non‐functional MA/AN and amino functional MA/AN/PAS were each melt blended into PE that was grafted with maleic anhydride (PE‐g‐MAnn) at 200 °C at 70:30 wt % PE‐g‐MAnn:co/terpolymer. After extrusion, the dispersed phase particle size (volume to surface area diameter, ) was coarse (12.6 μm) for the non‐reactive blend whereas it was much lower for the reactive blend ( = 1.2 μm). Coarsening after annealing at 150 °C was slow, but the domain sizes increased only slightly for both cases. The reactive blend was deemed sufficiently stable and thus was suitable as a candidate barrier material for further testing against olefins. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44177.     

Crystallization and mechanical behavior of covalent functionalized carbon nanotube/poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) nanocomposites

To improve the dispersity of multi‐walled carbon nanotubes (MWCNTs) in poly(3‐hydroxybutyrate‐co?3‐hydroxyvalerate) (PHBV) matrix, MWCNTs functionalized with carboxyl groups, hydroxyl groups, and atactic poly (3‐hydroxybutyrate) (ataPHB) through acid oxidation, esterification reaction, and “grafting from” method, respectively, were used to fabricate nanofiller/PHBV nanocomposites. The crystallization behavior, dispersion of MWCNTs before and after functionalization in PHBV matrices, and mechanical properties of a series of nanocomposites were investigated. The differential scanning calorimetry, wide‐angle X‐ray diffraction, and polarized optical microscope results suggested that the four types of MWCNTs acted as effective heterogeneous nucleation agents, inducing an increase in the crystallization rate, crystallinity, and crystallite size. Scanning electron microscope observations demonstrated that functionalized MWCNTs showed improved dispersion comparing with MWCNTs, suggesting an enhanced interfacial interaction between PHBV and functionalized MWCNTs. Consequently, the mechanical properties of the functionalized MWCNTs/PHBV nanocomposites have been improved as evident from dynamic mechanical and static tensile tests. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42136.     

Preparation and aqueous solution behavior of a ph‐responsive branched copolymer based on 2‐(diethylamino)ethyl methacrylate

pH‐Responsive amphiphilic branched copolymers were prepared from poly(ethylene glycol) methyl ether methacrylate (PEGMA), 2‐(diethylamino)ethyl methacrylate (DEAEMA), 2‐(tert‐butylamino)ethyl methacrylate (tBAEMA), and ethylene glycol dimethacrylate (EGDMA) utilizing a thiol‐modified free radical polymerization. The molecular structures of copolymers were confirmed by proton nuclear magnetic resonance spectroscopy (¹H NMR) and triple‐detection gel permeation chromatography (tri‐GPC). The aqueous solution behaviors of the obtained copolymers were investigated by dynamic light scattering (DLS). The DLS data showed that about 16 nm polymer particles comprising of hydrophobic poly(tert‐butylamino)ethyl methacrylate (PtBAEMA) and poly(diethylaminoethyl methacrylate (PDEAEMA) core, hydrophilic PEGMA corona were formed above pH 8. With the decrease of pH from 8 to 6, a dramatic increase in the hydrodynamic radius of polymer particles from 16 nm to 130 nm was observed resulting from the protonation of the PDEAEMA segment. Moreover, in vitro drug release behaviors of the resulting polymer assemblies at different pH values were also investigated to evaluate their potential as sustained release drug carriers. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42183.     

Surface modification of polyamide TFC membranes via redox‐initiated graft polymerization of acrylic acid

In this work, the redox‐initiated graft polymerization of acrylic acid (AA) onto the surface of polyamide thin film composite membranes has been carried out to enhance membrane separation and antifouling properties. The membrane surface characteristics were determined through the attenuated total reflection Fourier transform infrared spectra, scanning electron microscopy, atomic force microscopy, and water contact angles. The membrane separation performance was evaluated through membrane flux and rejection of some organic compounds such as reactive red dye (RR261), humic acid, and bovine serum albumin in aqueous feed solutions. The experimental results indicated that the membrane surfaces became more hydrophilic and smoother after grafting of AA. The modified membranes have a better separation performance with a significant enhancement of flux at a great retention. The fouling resistance of the modified membranes is also clearly improved with the higher maintained flux ratio and the lower irreversible fouling factor compared to the unmodified one. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45110.     

Flame‐retardant and morphological analysis of nitrogen heterocycle‐modified poly(vinyl alcohol) and their application for adsorption of heavy metal ions

The functional modification of poly (vinyl alcohol) (PVA) was conducted through phosphorus containing nitrogen heterocycles. This has been believed to have extensive thermal stability and heavy metal ion adsorption in the area of polymers. The heterocyclic modified polymers were characterized by Infra red (FTIR), Nuclear magnetic resonance spectroscopy, and elemental analysis. Thermogravimetric analysis studies displayed that phosphorus‐containing five membered and fused heterocyclic based PVA were less thermally stable than six membered compounds. Differential scanning calorimetric studies reported that the glass transition and melting point temperature of the heterocyclic modified PVA was higher than the pure PVA. X‐ray diffraction studies were done to analyze the structure of the modified polymer. Atomic force microscopy surface scans showed that the modified polymeric surface was found to have rough in micrometer scale. Modified PVA showed improved thermal stability, flame retardance, organosolubility, and surface roughness. The adsorption capacities of the modified PVA were determined for several heavy metal ions with the variation of pH. The adsorption capacity was found as 289 mg Pd²⁺/g of imidazole modified PVA and exhibited higher than other modified PVA. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Thermal and gas permeation properties of copolymers derived from 3‐methacryloxypropyltris(trimethylsiloxy)silane and adamantyl group‐containing methacrylate derivatives

Novel copolymer membranes derived from three types of adamantyl group‐containing methacrylate derivatives and 3‐methacryloxypropyltris(trimethylsiloxy)silane (SiMA) were synthesized via free radical polymerization. The thermal and permeation properties of these copolymer membranes were investigated. Copolymer membranes with less than 11.9 mol % adamantane content exhibited good membrane forming abilities that are suitable for permeation measurement. The decomposition temperature of all copolymers increased up to approximately 40–80°C with increasing adamantane content compared with poly(SiMA). Moreover, the glass transition temperature (T_g) of all copolymers increased up to approximately 46–60°C with increasing adamantane content compared with the theoretical value, which was estimated from Fox equation. 1‐Adamantyl methacrylate copolymer had the highest fractional free volume among the three types of adamantly group‐containing methacrylate derivatives. The gas permeability coefficient of this copolymer increased by 22–45% with increasing adamantane content compared with that of poly(SiMA). © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43129.     

Reactive modification and compatibilization of poly(lactide) and poly(butylene adipate‐co‐terephthalate) blends with epoxy functionalized‐poly(lactide) for blown film applications

Biodegradable blown films comprising of poly(lactide) (PLA) and poly(butylene adipate‐co‐terephthalate) (PBAT) were produced using epoxy functionalized‐poly(lactide) (EF‐PLA) reactive modifiers for rheological enhancement and compatibilization. The epoxy groups on the EF‐PLA modifiers react with PBAT forming an in situ copolymer that localizes at the blend interphase resulting in compatibilization of the polymer blend components. The EF‐PLA modified polymer blends have improved melt strength and the resultant films showed better processability as seen by increased bubbled stability. This allowed for blown films with higher PLA content (70%) compared to the unmodified control films (40%). The static charge build‐up typically experienced with PLA film blowing was decreased with the inclusion of EF‐PLA yielding films with better slip and softness. The compatibilization effect of the EF‐PLA modifiers resulted in significant improvement in mechanical properties. For example, dart test performance was up to four times higher than the control, especially at higher PLA concentrations. Therefore, the rheological enhancement and compatibilization effects of the EF‐PLA reactive modifiers make them ideally suited to create high PLA content films. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43310.     

Biodegradable polymer made of styrene and N‐benzyl‐4‐vinylpyridinium chloride

A copolymer of styrene with N‐benzyl‐4‐vinylpyridinium chloride (BVP), poly(styrene‐co‐N‐benzyl‐4‐vinylpyridinium chloride) (PST‐co‐BVP), was degradable by activated sludge in soil when the oligo‐styrene portion was sufficiently small. The degradation of the equimolar copolymer followed first‐order kinetics when the polymer sample was 1.0 or 0.5 g/kg and gave a half‐life of 5.6 days. The degradation of PST‐co‐BVP with a reduced BVP content did not follow first‐order kinetics under the aforementioned conditions but appeared to follow the kinetics when the amount of the polymer sample was sufficiently small. Under the ultimate conditions, the half‐life of PST‐co‐BVP that contained 10.6 mol % BVP was estimated to be 12.5 days, and the half‐life of PST‐co‐BVP that contained 5 mol % BVP was expected to be 30–40 days. The incorporation of 5 mol % BVP appeared sufficient for making PST‐co‐BVP substantially biodegradable if we did not expect exceptionally rapid degradation. PST‐co‐BVP was different from conventional polystyrene but possessed biodegradability. Random scission of the main chain much predominated over uniform scission from the end of the polymer chain in the biodegradation of PST‐co‐BVP. The cleavage of the main chain at BVP appeared predominant over that of oligo‐styrene. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 554–559. 2006     

Ionic conductivity and dielectric behavior of novel poly(vinyl formal)‐based single‐ion‐conductor polymer electrolytes

Novel single‐ion‐conductor polymer (SCP) electrolytes based on oxalate‐chelated‐borate‐structure‐grafted poly(vinyl formal) (PVFM) were synthesized via a solution casting technique. The influence of the molar ratio of ? OH and boron atoms in PVFM on the ionic conductivity (σ) of the SCP electrolytes at different temperatures was investigated with alternating‐current impedance spectroscopy in the frequency range of 0.01 Hz to 1 MHz. The results show that σ of the SCP electrolytes at 15–60 °C was about 10^?6–10^?5 S/cm, and temperature dependence of the conductivity of the electrolytes followed the Vogel–Tamman–Fulcher relationship. The dielectric behaviors of the SCP electrolytes were analyzed in view of the dielectric permittivity and dielectric modulus of the electrolytes. Dielectric analysis revealed that the transport of Li⁺ ions in the PVFM‐based SCP electrolytes mainly followed a hopping mechanism coupled with the segmental motion of the polymer chain. Additionally, a dielectric relaxation was found in the high‐frequency region; this was a thermally activated result and also implied the appearance of carrier hopping. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43510.     

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