Aliphatic–aromatic copolyesters containing phosphorous cyclic bulky groups

Synthesis of Sulfonated Poly(Arylene Ether Sulfone)s Containing Aliphatic Moieties for Effective Membrane Electrode Assembly Fabrication by Low-Temperature Decal Transfer Methods

The purpose of this study was to investigate the effect of the aliphatic moiety in the sulfonated poly(arylene ether sulfone) (SPAES) backbone. A new monomer (4,4'-dihydroxy-1,6-diphenoxyhexane) was synthesized and polymerized with other monomers to obtain partially alkylated SPAESs. According to differential scanning calorimetry analysis, the glass transition temperature (Tg) of these polymers ranged from 85 to 90 °C, which is 100 °C lower than that of the fully aromatic SPAES. Due to the low Tg values obtained for the partially alkylated SPAESs, it was possible to prepare a hydrocarbon electrolyte membrane-based membrane electrode assembly (MEA) with Nafion® binder in the electrode through the use of a decal transfer method, which is the most commercially suitable system to obtain an MEA of proton exchange membrane fuel cells (PEMFCs). A single cell prepared using this partially alkylated SPAES as an electrolyte membrane exhibited a peak power density of 539 mW cm-2.

Facile Synthesis, Characterization, and In Vitro Antimicrobial and Anticancer Activities of Biscoumarin Copolyester Bearing Pendant 3-(Trifluoromethyl)Styrene

Synthesis of random biscoumarin copolyester bearing pendant 3-(trifluoromethyl)styrene was prepared by the reaction of biscoumarin monomer 3 and hydroquinone 5 with azeloyl chloride. The influence of pendant 3-(trifluoromethyl)styrene unit on the properties of copolyester such as inherent viscosity, solubility, and thermal stability was investigated and compared in detail. The inherent viscosity and polydispersity index of the copolyester were found to be 0.15 dL/g and 1.36, respectively. The chemical structure of the copolyester was investigated by Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (¹H-NMR) spectroscopy. The physical properties of copolyester were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), and X-ray diffraction (XRD) technique. Agar disc diffusion method was employed to study the antimicrobial activity of the random copolyester. In vitro anticancer activity against lung cancer (Hep-2) cell line was also investigated.

Synthesis, Characterization, and In Vitro Antimicrobial and Anticancer Evaluation of Copolyester Bearing 4-Arylidene Curcumin in the Main Chain

Synthesis of random copolyester bearing 4-arylidene curcumin M₁ in the polymer backbone was prepared by solution polycondensation method. The influence of copolyester bearing 4-arylidene curcumin M₁ unit on the properties of copolyester such as inherent viscosity, solubility, and thermal stability was investigated and studied in detail. The inherent viscosity and polydispersity index of the copolyester were found to be 0.19 dL/g and 1.38, respectively. The chemical structure of the copolyester was investigated by Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (¹H-NMR) spectroscopy. The physical properties of copolyester were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), and X-ray diffraction (XRD) technique. Agar disc diffusion method was employed to study the antimicrobial activity of the random copolyester. In vitro anticancer activity against lung cancer (Hep-2) cell line was investigated.

Facile synthesis of new thermally stable and organo-soluble polyamide-imides from phosphorus-containing aromatic amines and various dianhydrides

Imide ring containing novel polyamide-imides (PAIs) were prepared by triphenyl phosphite-activated polycondensation of phosphorus-containing aromatic amines, bis(3-aminophenyl) isopropyl phosphine (BAP) and bis(3-aminophenyl) aminotolyl phosphine (TAP), with various diimide-diacids (DIDAS). All polymers were fully characterized by FTIR, 1H-NMR, 13C-NMR, 31P-NMR spectroscopy and elemental analysis. These polymers showed no significant weight loss below 419°C and glass transition temperatures (Tg) in the region of 231°C–290°C. The resulting polymeric films exhibited high optical transparency. The inherent viscosity of the synthesized polymers was in the range 0.55–0.85 dl/g and wide angle X-ray diffraction measurements revealed that these polymers were predominantly amorphous.

High performance new heteroaromatic poly(thiourea-imide-ester)s

A new dihydroxy monomer, 1-(2-hydroxypyridin-3-yl)-3-(2-(2-hydroxypyridin-3-yl)-1,3-dioxo-isoindoline-5-carbonyl)thiourea, with preformed trimellitic anhydride chloride-derived imide ring, pyridine and C=S moieties was synthesized. This compound was exploited to prepare three heteroaromatic poly(thiourea-imide-ester)s (PTIEs) by polycondensation with various diacid chlorides. Structural analysis of polymers was carried out by Fourier transformation infrared and nuclear magnetic resonance spectroscopy. PTIEs were readily soluble in polar solvents such as N, N-dimethylacetamide, dimethylformamide, dimethyl sulfoxide and N-methylpyrrolidone. Inherent viscosity and gel permeation chromatography measurements revealed high molar mass (140 × 102 to 101 × 102). One of the polymers showed crystalline behavior according to x-ray diffraction. Thermogravimetric analysis and differential scanning calorimetry were adopted for the thermal analysis of the polymers. Novel aromatic PTIEs possess high weight loss temperature ( T10) in the range 524–536°C and glass transition temperature of about 223–230°C.

Synthesis and Characterization of New Phosphorus-containing Poly(ester imide)s

New phosphorus-containing poly(ester imide)s were prepared via polycondensation in solution of 1,4-bis[N-(4-hydroxyphenyl)phthalimidyl-5-carboxylate]-2-(6-oxido-6H-dibenz <c,e ><1,2 >oxaphosphorin-6-yl)-naphthalene with different aromatic dicarboxylic acids using a SOCl2/pyridine condensing agent. The polymers showed high thermal stability having a decomposition temperature above 375 °C and char yield at 700 °C in the range of 54—56%. The glass transition temperature was in the range of 190—226 °C. Solutions of the polymers in N,N-dimethylformamide showed fluorescence having maximum emission wavelength in the range 405—425 nm. The polymers exhibited thermotropic liquid crystalline behavior.