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A more efficient route for the synthesis of phosphonated dimethyl isophthalate, disodium salt is shown to provide a significantly higher yield (42%), in contrast to a previously reported yield (15%). This higher yield enabled the synthesis of phosphonated poly(ethylene terephthalate) (PPET) ionomers using conventional melt polycondensation with ethylene glycol and dimethyl terephthalate. The physical...
Novel copolyester thermoplastics based on 4,4′-bibenzoate and 3,4′-bibenzoate moieties with ethylene glycol were synthesized via melt polycondensations. Crystallization behavior was modified by the additional incorporation of terephthalate or isophthalate units into the backbones. Copolyester compositions were verified by 1H NMR spectroscopy and molecular weights were assessed using inherent viscosity...
Gynecological cancer treatment strategies commonly employ pelvic brachytherapy, a technique that temporarily locates radioactive materials in or near the source of the tumor. Despite numerous advances in brachytherapy treatment protocols, advances in the required vaginal packing materials lag significantly. This paper describes a packing material for vaginal brachytherapy based on a poly(ethylene...
Segmented imidazolium ionenes with poly (tetramethylene oxide) (PTMO) soft segments and ionic, bis-imidazolium hard segments formed nonwoven fibrous mats upon electrospinning. The segmented imidazolium ionenes exhibited high thermal stability, excellent mechanical properties, and two glass transition temperatures indicative of microphase separation. Tensile analysis revealed strain-induced crystallization...
Phosphonium cation-based ionic liquids (ILs) are a readily available family of ILs that often offer superior properties compared to ammonium cation-based ILs. Recently investigated applications include extraction solvents, electrolytes in batteries and super-capacitors, and corrosion protection. At the same time, the range of cation–anion combinations available commercially has also increased in recent...
Reversible-addition fragmentation chain transfer (RAFT) polymerization enabled the synthesis of novel, stimuli-responsive, AB and ABA block copolymers. The B block contained oligo(ethylene glycol) methyl ether methacrylate (OEG) and was permanently hydrophilic in the conditions examined. The A block consisted of diethylene glycol methyl ether methacrylate (DEG) and [2-(methacryloyloxy)ethyl]trimethylammonium...
An unprecedented family of segmented polydimethylsiloxane poly(urea oxamide) (PDMS-UOx) copolymers displayed thermoplastic elastomeric behavior with improved thermomechanical properties compared to PDMS polyurea (PDMS-U) analogs. A two-step, PDMS end-capping sequence using diethyl oxalate and hydrazine generated difunctional oxamic hydrazide capped oligomers. Polymerization with HMDI provided high...
A new synthetic strategy using melt transesterification enabled selective control of ionic charge placement into the hard segment or soft segment block of segmented copolyesters. Dynamic mechanical analysis of sulfonated soft segment copolyesters revealed an increase in the low-T g transition and rubbery plateau storage modulus as a function of sulfonation level. Sulfonated hard segment copolyesters...
Adenine-functionalized ionenes (ionene-A) and thymine-functionalized ionenes (ionene-T) were synthesized from novel nucleobase-containing monomers from an efficient aza-Michael addition to an acrylate precursor. Complexes of ionenes with nucleobase-containing guest molecules (n-butyl thymine, nBT and n-butyl adenine, nBA) exhibited well-defined complementary hydrogen bonding interactions. Job’s analysis...
Nitroxide-mediated polymerization enabled the synthesis of cationic, imidazolium-containing triblock copolymers as a membrane for an electromechanical transducer. Nitroxide-mediated polymerization afforded poly(styrene-b-[1-ethyl-3-(4-vinylbenzyl)imidazolium bis(trifluoromethane sulfonyl)imide)]-b-styrene) in a controlled fashion as confirmed using aqueous size exclusion chromatography and 1 ...
Conventional free radical copolymerization of 9-vinylbenzyladenine (VBA) and 2-(dimethylamino)ethyl methacrylate (DMAEMA) with subsequent protonation afforded the synthesis of adenine-containing polyelectrolytes. All adenine-containing polyelectrolytes exhibited classical polyelectrolyte solution rheological behavior with scaling factors near 0.6 and 1.6 in the semidilute unentangled and semidilute...
Poly(ethylene glycol) (PEG)-based sulfonated polyurethanes bearing either sulfonated soft segments (SSSPU) or sulfonated hard segments (SHSPU) were synthesized using sulfonated monomers. Differential scanning calorimetry (DSC) revealed that sulfonate anions either in the soft segments or hard segments both increased the glass transition temperatures (T g ’s) of the soft segments and suppressed...
The imidazole ring is ubiquitous in nature and imidazole functionality plays a critical role in many structures within the human body, notably as histamine and histadine. Imidazoles offer many biophysical interactions including their ability to hydrogen bond with drugs and proteins. In contrast, imidazolium salts have lost their strong hydrogen-bonding ability through alkylation of both nitrogens,...
Imidazolium ionene segmented block copolymers were synthesized from 1,1′-(1,4-butanediyl)bis(imidazole) and 1,12-dibromododecane hard segments and 2000g/mol PTMO dibromide soft segments. The polymeric structures were confirmed using 1 H NMR spectroscopy, and resonances associated with methylene spacers from 1,12-dibromododecane became more apparent as the hard segment content increased. TGA...
Free radical copolymerization of n-butyl acrylate and a sulfobetaine methacrylamide derivative provided high molecular weight zwitterionic copolymers containing 6–13mol% betaine functionality, and the electrospinning of low T g zwitterionomers was explored for the first time. Copolymerizations were performed in dimethylsulfoxide (DMSO) rather than fluorinated solvents previously reported in...
Nano-tack (measured using AFM) and bulk-tack adhesive forces of blends of C 60 and either polystyrene-block-polybutadiene-block-polystyrene (SBS) or polystyrene-block-polyisoprene-block-polystyrene (SIS) triblock copolymer pressure sensitive adhesives were measured after exposure to white light irradiation. The nano-tack adhesive forces in C 60 –SIS/SBS were found to decrease with...
A monofunctional phosphine oxide containing endcapping reagent, 4-carboxyphenyl biphenyl phosphine oxide, was synthesized for the preparation of telechelic polyester oligomers. The chemical structure of the endcapping reagent was verified using NMR spectroscopy, mass spectroscopy, and elemental analysis. Phosphine oxide telechelic polyesters were prepared for the first time via copolymerization of...
The dielectric relaxation behavior of poly(acrylonitrile-co-methacrylonitrile) dispersed in a cured polydimethyl siloxane (PDMS) matrix as microcapsules was investigated over multiple thermal cycles and at varying concentrations. The copolymer microcapsules contained an isopentane core. In the PDMS matrix this copolymer displayed a pronounced relaxation signal at temperatures above the glass transition...
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