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A diamine containing heterocyclic pyridine and unsymmetrical carbazole substituents, 4-(9-ethyl-3-carbazole)-2,6-bis(4-aminophenyl)pyridine (CBAPP), was prepared for use in the synthesis of poly(pyridine-imide)s PI-1–8 by direct polycondensation with dianhydrides in N,N-dimethylacetamide (DMAc). The poly(pyridine-imide)s derived from the diamine are highly soluble in solvents such as N-Methyl-2-pyrrolidone (NMP) and DMAc at room temperature. Noncoplanar polyimide (PI-1) showed excellent solubility, high transparency, and high-performance mechanical properties. These polymers had relatively high glass transition temperatures and exhibited good thermal stability in both nitrogen (Td10 > 470 °C) and air (Td10 > 450 °C). The PI-3∼5 cannot form flexible and tough films due to the unsymmetrical carbazole moiety, rigid structure, and polar–polar interaction. However, through copolymerization technique these polymers (PI-6∼8) could be enhanced through the solubility, mechanical, and thermal properties. The optical properties included a strong orange fluorescence (540 nm) after protonation with acid. When the HCl concentration was increased, a new absorption band at approximately 350 nm appeared, and the intensity of the fluorescent peak at 380 nm observed in the neutral polymer solution decreased, along with the appearance of the new fluorescent peak at 540 nm. The poly(pyridine-imide)s presented here showed only slight fluorescence quenching in the presence of methanol. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 405–412

The fabrication of block copolymer (BCP) vesicles with controlled membrane permeability and promising stability remains a considerable challenge. Herein, a new type of pH-responsive and self-crosslinked vesicle based on a hydrolytically hindered urea bond is reported. This kind of vesicle is formed by the self-assembly of a pH-responsive and hydrolytically self-crosslinkable copolymer poly(ethylene glycol)-block-poly[2-(3-(tert-butyl)-3-ethylureido)ethyl methacrylate-co-2-(diethylamino)ethyl methacrylate] (PEG-b-P(TBEU-co-DEA)). The BCP can be easily synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of 2-(3-(tert-butyl)-3-ethylureido)ethyl methacrylate (TBEU) and 2-(diethylamino)ethyl methacrylate (DEA) using PEG-based macro-chain transfer agent. The copolymer could self-assemble into stable vesicles by the hydrophobic interaction and in situ cross-linking between amines and isocyanates after the hydrolysis of the hindered urea bonds without any catalyst. Dynamic light scattering (DLS) studies show that the vesicles exhibit enhanced stability against the dilution of organic solvent, and the size can be adjusted through the change of pH values. Moreover, the alkaline phosphatase-loaded vesicles can act as nano-reactor and enable free diffusion of small molecules into the vesicles, followed by the significantly improved fluorescence intensity of phosphate-caged fluorescein. This self-crosslinking and pH-sensitive vesicles may serve as a smart platform in controlled drug delivery and molecular reactor.

To improve the pervaporation performance in separating an aqueous ethanol solution, polyamide thin-film composite (TFC) membranes (m-tolidine-H-TMC/mPAN) were prepared through the interfacial polymerization reaction between trimesoyl chloride (TMC) and 2,2'-dimethylbenzidine hydrochloride (m-tolidine-H) on the surface of a modified polyacrylonitrile (mPAN) membrane. The effects of the feed ethanol concentration on the pervaporation performance and the durability of m-tolidine-H-TMC/mPAN TFC membranes were investigated. To choose the optimal mPAN membrane as the TFC substrate, the effect of hydrolysis time on the chemical properties and separation performance of an mPAN substrate was also studied. An appropriate hydrolysis time of 15 min was chosen to obtain the mPAN substrate due to the corresponding high permeation flux. The m-tolidine-H-TMC/mPAN TFC membrane exhibited a high pervaporation performance for ethanol dehydration. A positron annihilation lifetime spectroscopy experiment was used to estimate the mean free-volume radius of the m-tolidine-H-TMC polyamide selective layer, which lay between the radii of the water and ethanol molecules. © 2013 Society of Chemical Industry

A high-glass-transition-temperature polynorbornene, poly(NBEDPY), containing chromophore groups was synthesized by ring-opening metathesis polymerization (ROMP) using Grubbs' catalysts; poly(HNBEDPY) was obtained by the reduction of poly(NBEDPY). The glass transition temperatures (Tg) of poly(NBEDPY) and hydrogenated poly(HNBEDPY) were as high as 250 °C and 220 °C, respectively, because of the rigid dipyrene groups, which are higher than those of commercially available ring-opened hydrogenated polynorbornenes (JSR ARTON®; 120–165 °C). The 10% weight-loss temperatures of hydrogenated poly(HNBEDPY) and poly(NBEDPY) were up to 450 °C and 400 °C, respectively. A hydrogenated poly (HNBEDPY) film showed excellent transparency (over 91%). The photoluminescence emission spectra of poly(HNBEDPY) showed strong solvent-polarity dependence, revealing that poly (HNBEDPY) underwent remarkable bathochromic shifts with an increase in solvent polarity. Poly(HNBEDPY) also showed remarkable fluorescent solvatochromism (blue in toluene, greenish yellow in dimethyl sulfoxide). The cyclic voltammogram of poly(HNBEDPY) film cast onto an indium tin oxide (ITO)-coated glass substrate exhibited one reversible oxidation redox couple at 0.55 V versus Ag/Ag+ in acetonitrile solution. The electrochromic characteristics of poly(HNBEDPY) showed reversibility, with a color change from its green neutral form to dark red upon the application of potentials from 0 to 1.0 V. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

A new electrochromic norbornene derivative containing triphenylamine groups (NBDTPAC8) was synthesized using norbornene amine and bromotriphenylamine. NBDTPAC8 was used in ring-opening metathesis polymerization to obtain poly(NBDTPAC8) using different Grubbs' catalysts and followed by hydrogen reduction to obtain poly(HNBDTPAC8). The glass transition temperatures (Tg) of poly(NBDTPAC8) and hydrogenated poly(HNBDTPAC8) were 132 and 89 °C, respectively. Poly(HNBDTPAC8) film exhibited a fluorescence maximum around 416 nm with a quantum yield of up to 60%. Hydrogenated poly(HNBDTPAC8) film showed excellent transparency (up to 93%). Poly(HNBDTPAC8) showed cyclic voltammetric and electrochromic behaviors similar to those of poly(NBDTPAC8). The cyclic voltammogram of a poly(HNBDTPAC8) film cast onto an indium tin oxide (ITO)-coated glass substrate exhibited three reversible oxidation redox couples at 0.69, 0.94 and 1.38 V versus Ag/Ag+ in an acetonitrile solution. The electrochromic characteristics of poly(HNBDTPAC8) showed excellent stability and reversibility, with multi-staged color changes from its colorless neutral form to green, light blue and dark blue upon the application of potentials ranging from 0 to 1.60 V. The color switching time and bleaching time of the poly(HNBDTPAC8) film were 6.2 s and 4.3 s at 1175 nm and 6.6 s and 4.4 s at 970 nm, respectively. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.

Novel bi-triphenylamine-containing aromatic dibro- mide M3, N,N-bis(4-bromophenyl)-N 0 ,N 0 -dipheny-l,4-phenylene- diamine, was successfully synthesized. The novel conjugated polymer P1 having number-average molecular weight of 1.31 � 10 4 was prepared via Suzuki coupling from the dibromide M3 and 9,9-dioctylfluorene-2,7-diboronic acid bis(1,3-propane- diol) ester. Polymer P1 had excellent thermal stability associ- ated with a high glass-transition temperature (Tg ¼ 141 � C). The hole-transporting and UV-vis-near-infrared electrochromic properties were examined by electrochemical and spectroelec- trochemical methods. Cyclic voltammograms of the conjugated polymer films cast onto indium-tin oxide-coated glass sub- strates exhibited two reversible oxidation redox couples at E1/2 values of 0.73 and 1.13 V versus Ag/Ag þ in acetonitrile solu- tion. The hole mobility of the conjugated polymer P1 revealed � 10 � 3 cm 2 V � 1 s � 1 , which is much higher than that of other conjugated polymer systems. The observed UV-vis-near- infrared absorption change in the conjugated polymer film P1 at applied potentials ranging from 0.00 to 1.23 V are fully reversible and associated with strong color changes from pale yellowish in its neutral form to green and blue in its oxidized form. Using a combination of experimental study and theo- retical investigation, we proposed an oxidation mechanism based on molecular orbital theory, which explains the cyclic voltammetry experimental results well. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4654- 4667, 2010

A new rapid switching near-IR electrochromic conjugated propeller-shape polymer (PBTPAFL) with lower oxidation potential containing a di-triarylamine group was synthesized via Suzuki coupling approach. The observed UV-vis-NIR absorption changes in the PBTPAFL film at various potentials are fully reversible and associated with strong color changes from the original light green to dark green and then to a Prussian blue. Excellent continuous cyclic stability of the electrochromic characteristics with a rapid color switching time 2.58 s and bleaching time 1.76 s was found as well. Compared with P1 and P2, the introduction of more electron-donating propyl phenyl group in the para position of PBTPAFL lowered the oxidative potential and prevented coupling reaction during the electrochromic procedure. The high molecular weight conjugated polymer having high thermal stability with T d10 more than 450 °C has excellent solubility in common organic solvents such as NMP, THF, chloroform, toluene, xylene, and benzene at room temperature (25 °C) due to the propeller-shape structure and long alkyl chain on fluorene. Herein, from the combination of the experimental and computational study, we proposed a mechanism on the basis of the molecular orbital theory to explain the electrochromic oxidation behavior.

A novel dibromo compound containing unsymmetrical substituted bi-triarylamine was synthesized. A conjugated polymer was prepared via the Suzuki coupling from the newly prepared dibromo compound and 9,9-dioctylfluorene-2,7-bis(tri-methyleneboronate). The glass transition temperature (T g ) of the conjugated polymer was 140 °C, 10% weight-loss temperatures (T d10 ) in nitrogen was 458 °C, and char yield at 800 °C in nitrogen higher than 64%. Cyclic voltammogram of the polymer film cast onto an indium-tin oxide (ITO)-coated glass substrate exhibited two reversible oxidation redox couples at 0.70 and 1.10 V versus Ag/Ag + in acetonitrile solution. The polymer films revealed excellent stability of electrochromic characteristics, with a color change from yellow green of the neutral form to the dark green and blue of oxidized forms at applied potentials ranging from 0 to 1.3 V. The color switching time and bleaching time were 4.25 and 7.22 s for 860 nm and 5.51 s and 6.48 s for 560 nm.

A bipolar dibromo monomer, bis-(4-bromophenyl)[4-(3,5-diphenyl-1,2,4-triazole-4-yl)-phenyl]amine (9), containing electro-rich triphenylamine and electro-deficient 1,2,4-triazole moieties was newly synthesized and characterized. Two fluorescent fluorene-based conjugated copolymers (TPAF, TPABTF) were prepared via facile Suzuki coupling from the dibromo bipolar monomer, 4,7-dibromo-2,1,3-benzothiadiazole (BTDZ), and 9,9-dioctylfluorene. They were characterized by molecular weight determination, IR, NMR, DSC, TGA, solubility, absorption and photoluminescence spectra, and cyclic voltammetry. The polymers showed good solubility in common organic solvents such as dichloromethane, chloroform, tetrahydrofuran, and dichlorobenzene at room temperature. They had glass transition temperatures (T g ) higher than 135 °C and 5% degradation temperatures in nitrogen atmosphere were higher than 428 °C. Single layer polymer light-emitting diodes (PLED) of ITO/ PEDOT:PSS/polymer/metal showed a blue emission at 444 nm and Commission Internationale de I'Eclairage (CIE) 1931 color coordinates of (0.16, 0.13) for TPAF. The device using TPABTF as emissive material showed electroluminescence at 542 nm with CIE1931 of (0.345, 0.625), low turn-on voltage of 5 V, a maximum electroluminance of 696 ed/m 2 , and a peak efficiency of 2.02 cd/A.

A new diiodo monomer containing heterocyclic pyridine and carbazole groups was synthesized via Chichibabin reaction and used in the preparation of a conjugated polymer via Suzuki coupling approach. The conjugated polymer was highly soluble in common organic solvents such as NMP, THF, dichloromethane, chloroform, toluene, xylene, and benzene at room temperature. The polymer had high glass transition temperature at 191 °C and Td10 at 434 °C in nitrogen atmosphere. The pristine polymer exhibited the UV–vis maximum absorption at 355 nm and shifted to 420 nm after protonation. The emission of the polymer in THF solution changed from the blue region with maximum peak at 400 nm to the yellow region with maximum peak at 540 nm after protonated by HCl, and the intensity of emission depended on the concentration of acid. The polymer also showed electrochromic behavior under applied voltage. The emission color of the polymer film changed from blue (435 nm) to yellow (570 nm) when 2.5 V bias voltage was applied. The polymer also exhibited write-once and read-many-times (WORM) polymer memory effect with tristable states. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 991–1002, 2009

A new diacid containing optically active functional groups, N,N′-(4,4′-diphthaloyl)-bis-L-leucine diacid (3), was synthesized and used in a preparation of a series of poly(amide-imide)s (PAIs) by direct polycondensation with various aromatic diamines in N-methyl-2-pyrrolidinone (NMP). All polymers derived from diacid (3) were highly organosoluble in the solvents like N-methyl-2-pyrrolidinone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, tetrahydrofuran, γ-butyrolactone, cyclohexanone, and chloroform at room temperature or upon heating. Inherent viscosities of the PAIs were found to range between 0.34 and 0.61·dL g−1. All the PAIs afforded flexible and tough films. The glass-transition temperatures of these PAIs were recorded between 212 and 237°C by differential scanning calorimetry, and the 10% weight loss temperatures were ranging from 372 to 393°C and 336–372°C under nitrogen and air, respectively. The polyimide films had a tensile strength in the range of 63–88 MPa and a tensile modulus in the range of 1.2–1.7 GPa. Optically active PAIs exhibited specific rotations in the range of −10.58° to −38.70°. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

Cyclization of deproteinized natural rubber (DPNR) or purified natural rubber latex was effectively performed in latex phase by using trimethylsilyl-trifluoromethane sulfonate or trimethylsilyl triflate (TMSOTF) as a novel catalyst, which is still not reported in the case of natural rubber latex. Various cyclization conditions affecting the degree of cyclization were studied, such as dry rubber contents, temperature, TMSOTF concentrations, and time. The cyclized products were characterized by FTIR, Raman, 1H-, and 13C-NMR spectroscopies, as well as DSC and TGA. The degree of cyclization was estimated by 1H-NMR spectrum. It was found that the degree of cyclization in NR was a function of cyclization conditions. The thermal stability of cyclized DPNR increased with the degree of cyclization. Solubility of the obtained rubber was good in chloroform, toluene, cyclohexanone, and cyclohexane, and bad in tetrahydrofuran. The average number molecular weight of cyclized DPNR with 76% degree of cyclization was about 4.2 × 104 g/mol. On the basis of FTIR, Raman, 1H-, and 13C-NMR, the CC of cyclized DPNR dramatically decreased after prolonged reaction time. In addition, the topology of cyclization DPNR particles was rough on its rubber particle as analyzed by TEM. The mechanism for this reaction will also be discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007.

A new diamine containing a pyridine heterocyclic group and a naphthalene substituent, 4-(2-naphthyl)-2,6-bis(4-aminophenyl) pyridine (NBAPP), was synthesized with the Chichibabin reaction and used in the preparation of poly(pyridine imide) by direct polycondensation with 4,4′-hexafluoroisopropylidenediphathalic anhydride in N-methyl-2-pyrrolidinone (NMP). The poly(pyridine imide) derived from diamine NBAPP with naphthalene substituents was highly organosoluble: it was soluble in tetrahydrofuran, NMP, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide, and γ-butyrolactone at room temperature and in pyridine, dimethyl sulfoxide, and cyclohexanone upon heating at 70 °C. The poly(pyridine imide) was converted into lightly colored, optically transparent, flexible, and tough polyimide films via casting onto glass from a DMAc solution. This polymer exhibited good thermal stability (temperature of 10% weight loss = 527 °C) in air and high dielectric constants (as high as 4.20 at 1 kHz). The polyimide films had a tensile strength of 102 MPa and a tensile modulus of 1.8 GPa. As for the optical properties, the polymer exhibited UV–vis absorption bands in the region of 223–450 nm and possessed strong green-yellow fluorescence (500 nm) after being protonated with acid. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2367–2374, 2007

Pure exo-functional norbornene monomers containing various chromophores such as fluorene, pyrene, and carbazole were successfully prepared via the Diels–Alder reaction and condensation reaction. The living ring-opening metathesis polymerization (ROMP) of a fluorene-containing monomer, exo-2-(fluorene-9-ylcarboxymethyl)norborn-5-ene (exo-1), was observed and confirmed by the formation of a diblock copolymer and a linear relationship between the number-average molecular weight and [M]/[I] ratios ([M] = monomer concentration; [I] = initiator concentration). The synthesis and characteristics of novel fluorene-containing polymers based on pure exo-1 are reported with Grubbs catalyst I {RuCl2(CHPh)[P(C6H11)3]2} with a high molecular weight of 3.18 × 104 in 90 s ([M]/[I] = 100). However, the ROMP of pyrene- and carbazole-containing monomers [exo-5-(pyrene methoxy carbonyl)bicyclo[2.2.1]hept-2-ene and exo-5-(carbazole ethoxy carbonyl)bicyclo[2.2.1]hept-2-ene, respectively] were carried out in a nonliving fashion. All the chromophore-containing polymers showed excellent solubility in various organic solvents, particularly in chloroform, N-methyl-2-pyrrolidinone, and 1,2-dichlorobenzene. The glass transition temperatures of polynorbornenes containing various chromophores were determined to be 80–109 °C (by differential scanning calorimetry) higher than that of ring-opened polynorbornene (glass transition temperature = 35 °C), indicating that the incorporation of the pendant aromatic moieties (e.g., fluorene, pyrene, and carbazole) could enhance the transition temperature for segmental motions of polymer chains. The photoluminescence spectra of all polymer solutions showed a strong emission in the blue region of the visible spectra. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3022–3031, 2007

Ring opening metathesis is an important class of controlled polymerization techniques. Synthesis of novel polynorbornene derivatives with functional groups designed for application in crosslikable and self assembling materials, and the polymerizations via ROMP and/or free radical polymerization are introduced. Novel monomers and/or macroinitiators for combination of two polymerization techniques are useful for controlling molecular architecture. The sequence of using controlled polymerization techniques affects the molecular structure and the properties of resulting polymers.

Novel optically transparent and highly organo-soluble alicyclic polyimides derived from bulky alicyclic diamine containing trifluoromethyl group on either side, 1,1-bis[4(2-trifluoromethyl-4aminophenoxy)phenyl]-4-tert-butylcyclohexane (BTFAPBC), were prepared. All polymers showed excellent solubility in various organic solvents like N-methyl-2-pyrrolidinone (NMP), N,N-dimethyl acetamide (DMAc), N,N-dimethyl formamide (DMF), pyridine, cyclohexanone, and γ-butyrolactone. The cut-off wavelength and 80% transmission wavelength for polyimides ranged from 362 to 407 nm and 436 to 492 nia, respectively. Polyimides with alicyclic tert-butylcyclohexyl cardo and trifluoromethyl substituents exhibited low dielectric constants ranging from 3.38 to 4.07 (at 1 KHz). Inherent viscosities of the polyimides were found to be in the range of 0.52-1.00 dL·g -1 . Polyimides showed glass transition temperatures in the range of 231-262 °C, and possessed a coefficient of thermal expansion (CTE) of 66-79 ppm.°C -1 . Thermogravimetric analyses of the polyimides revealed high thermal stability and decomposition temperature more than 450 °C in nitrogen atmosphere. The 10% weight loss temperature was found to be in the range of 453-544 and 413-502 °C in nitrogen and air atmospheres, respectively. The polyimide films had a tensile strength ranging from 84 to 100 MPa. The elongation at break varied from 6 to 12% and the tensile modulus varied from 1.1 to 2.1 GPa.

A novel organosoluble polynorbornene bearing a polar, pendant, ester-bridged epoxy group [poly(oxiran-2-ylmethyl 2-methylbicyclo[2.2.1]hept-5-ene-2-carboxylate) (polyOMMC)] was prepared via the living ring-opening metathesis polymerization (ROMP) of active norbornenes with a Ru catalyst. PolyOMMC exhibited excellent solubility in a variety of solvents. The number-average molecular weight of polyOMMC linearly increased with the [M]/[I] ratio (where [M] is the monomer concentration and [I] is the initiator concentration), and a narrow polydispersity of 1.09–1.19 was observed; this was considered a living polymerization. When ROMP of oxiran-2-ylmethyl 2-methylbicyclo[2.2.1]hept-5-ene-2-carboxylate with [M]/[I] = 350 was carried out at 30 °C in CH2Cl2, the number-average molecular weight (7.01 × 104; polydispersity index = 1.07) was close to the calculated molecular weight (7.28 × 104), and a diblock copolymer was observed after the addition of another monomer ([M]/[I] = 350) with an increase in the number-average molecular weight (1.60 × 105; polydispersity index = 1.11), which was close to the calculated molecular weight (1.61 × 105). The modified polynorbornenes retained good solubility in methylene chloride, tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrdione. High-performance polynorbornenes with active epoxy groups could be designed with great potential for applications in photoresists, UV curing, and elastomers. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4428–4434, 2006

Novel star-like polymeric materials with high cis content could be obtained by using α-norbornenyl macromonomers and highly stable macroinitiators derived from an active norbornene derivative [5-(2-bromo-2-methylpropionylaminomethyl)bicyclo[2.2.1]hept-2-ene (NBBrMPAM)], which was synthesized by the reaction of norbornene methylene amine and 2-bromo-2-methylpropionyl bromide. The α-norbornenyl macromonomer (NBPMMA), which is polymethyl methacrylate containing norbornenyl end group, was prepared by atom transfer radical polymerization (ATRP) using NBBrMPAM as an initiator. Star-like polynorbornene with high cis microstructure (cis/trans = 72/28) was obtained directly by ring-opening metathesis polymerization of NBPMMA macromonomer having number molecular weight (Mn) as low as 6.39 × 103. Random ring-opening metathesis copolymerization of NBPMMA and norbornene derivative containing carbazole group (NBCbz) was carried out at 25 °C by using Ru catalyst [(Cy3P)2Cl2Ru = CHPh, Cy = cyclohexyl, Ph = phenyl]. High cis (cis/trans = 63/37) organo-soluble star-like random poly(NBPMMA-co-NBCbz) was successfully obtained with high number-average molecular weight (Mn) of 4.76 × 104 and molecular weight distribution polydispersity index of 1.78. Organo-soluble comb-shaped copolymers with MMA could be successfully obtained using ATRP macroinitiator [poly(HNBBrMPAM)] in diluted macroinitiator solution with a concentration less than 3.64 × 10−2 mol.L−1. This is the first ever attempt to prepare novel star-like organo-soluble polymeric materials with high cis microstructure via the combination of ring-opening metathesis polymerization and ATRP. Multimodification could be considered to be carried out by using the functional bromo group at the end of side chains. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3382–3392, 2006

Diblock copolymers of 5-(methylphthalimide)bicyclo[2.2.1]hept-2-ene (NBMPI) and 1,5-cyclooctadiene were synthesized by living ring-opening metathesis polymerization with a well-defined catalyst {RuCl2(CHPh)[P(C6H11)3]2}. Unhydrogenated diblock copolymers showed two glass transitions due to poly(NBMPI) and polybutadiene segments, such as two glass-transition temperatures at −86.5 and 115.3 °C for poly1a and −87.2 and 115.3 °C for poly1b. However, only one melting temperature could be observed for hydrogenated copolymers, such as 119.8 °C for poly2a and 121.7 °C for poly2b. The unhydrogenated diblock copolymer with the longer poly(NBMPI) chain (poly1a; temperature at 10% mass loss = 400 °C) exhibited better thermal stability than the one with the shorter poly(NBMPI) chain (poly1b; temperature at 10% mass loss = 385 °C). Two kinds of hydrogenated diblock copolymers, poly2a and poly2b, exhibited relatively poor solubility but better thermal stability than unhydrogenated diblock copolymers because of the polyethylene segments. Poly[(hydrochloride quaternized 2-norbornene-5-methyleneamine)-b-butadiene]-1 (poly3a) was obtained after the hydrolysis and quaternization of poly1a. Dynamic light scattering measurements indicated that the hydrodynamic diameters of the cationic copolymer (poly3a) in water (hydrodynamic diameter = 1580 nm without salt), methanol/water (4/96 v/v; hydrodynamic diameter = 1500 nm without salt), and tetrahydrofuran/water (4/96 v/v; hydrodynamic diameter = 1200 nm without salt) decreased with increasing salt (NaCl) concentration. The effect of temperature on the hydrodynamic diameter of hydrophobically modified poly3a was also studied. The inflection point of the hydrodynamic diameter of poly3a was observed at various polymer concentrations around 30 °C. The critical micelle concentration of hydrophobically modified poly3a was observed at 0.018 g dL−1. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2901–2911, 2006

A novel doubly polymerizable functional norbornene, 5-(methacryloyloxyethylamino carboxylmethyl)bicyclo[2.2.1]hept-2-ene (NBMOACM), was prepared. The ring-opening metathesis polymerization (ROMP) of NBMOACM was carried out to prepare polymers with crosslinkable side chains with the Grubbs catalyst. No gel formation occurred during the ROMP of NBMOACM. The 1H NMR spectrum of poly(NBMOACM) showed broad signals between 5.10 and 5.40 ppm, corresponding to the vinyl protons of the cis and trans double bonds of the ring-opened polymer. Increasing the ratio of the monomer concentration to the catalyst concentration resulted in the formation of higher molecular weight polymers. Poly(NBMOACM) was incorporated into poly(methyl methacrylate) [poly(MMA)] to produce AB crosslinked materials. These crosslinked materials [1 wt % poly(NBMOACM), 10% weight loss temperature = 300 °C in air] had higher thermal stability than pure poly(MMA) (10% weight loss temperature = 276 °C in air). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6287–6298, 2006

New polyamides were prepared directly from a diamine, bis[4-(2-trifluoro-methyl 4-aminophenoxy)phenyl] diphenylmethane, containing an electron-withdrawing trifluoromethyl group and a kink diphenylmethylene linkage with various aromatic dicarboxylic acids having inherent viscosities ranging from 0.66 to 0.83 dL g -1 . All the polyamides showed outstanding solubility and could be easily dissolved in amide-type polar aprotic solvents (e.g., N-methyl-2-pyrrolidinone, N,N-dimethylaceta-mide, and N,N-dimethylformamide) and even dissolved in less polar solvents (e.g., pyridine, cyclohexanone, and tetrahydrofuran). The dielectric constants of the polyamide films were 3.37-3.87 (100 KHz) and decreased with an increase in the frequency, which ranged from 1 Hz to 100 KHz. A low coefficient of thermal expansion for the polyamides was observed in the range of 54-78 ppm/°C (by thermomechanical analysis). These polyamides showed excellent thermal stability, and the 10% weight loss temperatures were in the range of 484-507 °C in an atmosphere of nitrogen. The polymers had an initial modulus of 1.8-2.2 GPa. The polyamides with kink and electron-withdrawing trifluoromethyl units afforded light-color polymer films with high transmittance in the visible region (400-700 nm), and their cutoff wavelength was lower than 362 nm.

A series of polymer–clay nanocomposite (PCN) materials that consist of organosoluble polyimide and layered montmorillonite clay were prepared by the solution dispersion technique. The organosoluble polyimide containing non-coplanar moiety in diamine monomer and flexible bridging linkages in dianhydride monomer was synthesized by chemical imidization. The as-synthesized PCN materials were characterized by infrared spectroscopy, wide-angle powder X-ray diffraction, and transmission electron microscopy. The organosoluble polyimide showed better corrosion resistance compared to polyaniline, poly(o-ethoxyaniline) and poly(methyl methacrylate) by using a series of standard electrochemical corrosion measurements of corrosion potential, polarization resistance, and corrosion current in 5 wt % aqueous NaCl electrolyte. Polyimide–clay nanocomposite materials incorporated with low loading of clay were found to further improve corrosion inhibition over pure polyimide. Effects of the material composition on the O2/H2O molecular permeability, optical clarity, and thermal properties of polyimide–clay nanocomposite materials were studied by molecular permeability analysis, UV–visible transmission spectra, thermogravimetric analysis, and differential scanning calorimetry, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3573–3582, 2004

A new diimide–diacid chloride (3) containing a noncoplanar 2,2′-dimethyl-4,4′-biphenylene unit was synthesized by treating 2,2′-dimethyl-4,4′-diamino-biphenylene with trimellitic anhydride followed by refluxing with thionyl chloride. Various new poly(ester-imide)s were prepared from 3 with different bisphenols by solution polycondensation in nitrobenzene using pyridine as hydrogen chloride quencher at 170°C. Inherent viscosities of the poly(ester-imide)s were found to range between 0.31 and 0.35 dL g−1. All of the poly(ester-imide)s, except the one containing pendent adamantyl group 5e, exhibited excellent solubility in the following solvents: N,N-dimethylformamide, tetrahydrofuran, tetrachloroethane, dimethyl sulfoxide, N,N-dimethylacetamide, N-methyl-2-pyrrolidinone, m-cresol, o-chlorophenol, and chloroform. The polymers showed glass-transition temperatures between 166 and 226°C. The 10% weight loss temperatures of the poly(ester-imide)s, measured by TGA, were found to be in the range between 415 and 456°C in nitrogen. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2486–2493, 2004

A series of polymer–clay nanocomposite (PCN) materials consisting of 1,4-bis(4-aminophenoxy)-2-tert-butylbenzene–4,4′-oxydiphthalic anhydride (BATB–ODPA) polyimide (PI) and layered montmorillonite (MMT) clay were successfully prepared by an in situ polymerization reaction through thermal imidization up to 300°C. The synthesized PCN materials were subsequently characterized by Fourier-Transform infrared (FTIR) spectroscopy, wide-angle powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). The effects of material composition on thermal stability, mechanical strength, molecular permeability and optical clarity of bulk PI and PCN materials in the form of membranes were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), molecular permeability analysis (GPA) and ultraviolet-visible (UV/VIS) transmission spectra, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1072–1079, 2004

A new diamine containing isopropylidene, methyl substituted arylene ether, and trifluoromethyl groups, 2,2-bis[4-(2-trifluoromethyl-4-aminophenoxy)-3,5-dimethylphenyl]propane (BTADP), was synthesized and used in preparation of a series of polyimides by direct polycondensation with various aromatic tetracarboxylic dianhydrides in N, N-dimethylacetamide (DMAc). All polymers derived from diamine (BTADP) with trifluoromethyl substituents were highly organosoluble in the solvents, like N-methyl-2-pyrrolidinone (NMP), N,N-dimethylacetamide, N,N-dimethylformamide (DMF), pyridine, chloroform, tetrahydrofuran (THF), dimethyl sulfoxide (DMSO), dichloromethane, cyclohexanone, and γ-butyrolactone at room temperature or upon heating at 70 °C. Inherent viscosities of the polyimides were found to range between 0.58 and 0.97 dL·g−1. These polyimides had glass transition temperatures between 256 and 307 °C, and their 10% mass loss temperatures ranged from 440 to 462 °C and 421 to 443 °C under nitrogen and air, respectively. These polyimides had low dielectric constants in the range of 2.84–3.09. All the polyimides could be cast into films from DMAc solutions and were thermally converted into color lightness, optically transparent, flexible, and tough polyimides. The polyimide films had a tensile strength in the range of 83–97 MPa and a tensile modulus in the range of 2.0–2.2 GPa. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5766–5774, 2004

A new kink diamine with trifluoromethyl group on either side, bis[4-(2-trifluoromethyl-4-aminophenoxy)phenyl]diphenylmethane(BTFAPDM), was reacted with various aromatic dianhydrides to prepare polyimides via poly ( amic acid ) precursors followed by thermal or chemical imidization. Polyimides were prepared using 3,3', 4,4'-biphenyltetracarboxylic dianhydride(1), 4,4'-oxydiphthalic anhydride(2), 3,3',4,4'-benzophenonetetracarboxylic dianhydride (3), 4,4'-sulfonyldiphthalic anhydride(4), and 4,4'-hexafluoroisopropylidene-diphathalic anhydride(5). The fluoro-polyimides exhibited low dielectric constants between 2.46 and 2.98, light color, and excellent high solubility. They exhibited glass transition temperatures between 227 and 253°C, and possessed a coefficient of thermal expansion (CTE) of 60-88 ppm/°C. Polymers PI-2, PI-3, PI-4, PI-5 showed excellent solubility in the organic solvents: N-methyl-2-pyrrolidinone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), pyridine and tetrahydrofuran (THF). Inherent viscosity of the polyimides were found to range between 0.58 and 0.72 dLg-1. Thermogravimetric analysis of the polyimides revealed a high thermal stability decomposition temperature in excess of 500°C in nitrogen. Temperature at 10 % weight loss was found to be in the range 506-563°C and 498-557°C in nitrogen and air, respectively. The polyimide films had a tensile strength in the range 75-87 MPa; tensile modulus, 1.5-2.2 GPa; and elongation at break, 6-7%.

The separation of aqueous alcohol mixtures was carried out by use of a series of novel aromatic polyamide membranes. The aromatic polyamides were prepared by the direct polycondensation of 2,2′-dimethyl-4,4′-bis(aminophenoxyl)biphenyl (DBAPB) with various aromatic diacids, such as terephthalic acid (TPAc), 5-tert-butylisophthalic acid (TBPAc), and 4,4′-hexafluoroisopropylidenedibenzoic acid (FDAc). The pervaporation and evapomeation performance of these novel aromatic polyamide membranes for dehydrating aqueous alcohol solution were investigated. The solubility of ethanol in the aromatic polyamide membranes is higher than that of water, but the diffusivity of water through the membrane is higher than that of ethanol. The effect of diffusion selectivity on the membrane separation performances plays an important role in the evapomeation process. Compared with pervaporation, evapomeation effectively increases the permselectivity of water. Moreover, the effect of aromatic diacids on the polymer chain packing density, pervaporation, and evapomeation performance were investigated. It was found that the permeation rate could be increased by introduction of a bulky group into the polymer backbone. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2688–2697, 2003

The extent of intra- and interchain associations of (un)charged water-soluble monomers in the homogeneous and micellar solutions was studied with steady-state fluorescence spectroscopy. Fluorescence spectroscopic experiments were performed on uncharged (acryl amide) and charged hydrophilic monomers [zwitterionic 3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate (DMAPS), etc.] with pyrene as a probe. In both the homogeneous and micellar solutions, linear Stern–Volmer plots were obtained that implied that the quenching process can be considered as totally dynamic. The Stern–Volmer constant (KSV) for DMAPS decreased with an increasing dielectric constant of solvent and the concentration of simple electrolyte. An abrupt decrease in KSV was observed in the presence of a small amount of anionic emulsifier [below the critical micelle concentration (cmc)]. The dependence of KSV on pH for DMAPS was described by a curve with a maximum at about pH = 7. This was interpreted in terms of segregation of DMAPS and the variation of a optimal microenvironment for the probe and quencher with pH. The quenching rate in the micellar solutions strongly increased above the cmc but was lower than that in the homogeneous solutions. In the micellar solutions (above the cmc), the microenvironment for an interaction between the probe and quencher was suggested to be the whole microdroplet. The dependence of KSV on pH for DMAPS is described by a curve with a maximum at about pH = 9.3. The synergistic effect arises from the segregation of charged quencher molecules within the microdroplets. The complex (or strong interaction) between quencher and additive(s) is supposed to increase the dynamic nature of microdroplets that provides an optimal microenvironment for probe and quencher. A good coemulsifier, however, removes quencher from the interface and creates a barrier for entering monomer (quencher) into the core of micelles; therefore, quenching is depressed. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 571–581, 2003

Naphthalene-labeled cationic poly(hydrochloride-quaternized 2-norbornene-5-methyleneamine), poly(HCQNBMA)/NA, has been prepared by ring-opening metathesis polymerization (ROMP), using {RuCl 2 (CHC 6 H 5 )-[P(C 6 H 11 ) 3 ] 2 } as a catalyst in methylene chloride, followed by hydrogenation, hydrolysis, and quaternization. The effect of salt addition on the aqueous solution properties of poly(HCQNBMA)/NA was examined in terms of reduced viscosity, surface tension and fluorescence studies. The reduced viscosity of poly(HCQNBMA)/NA is dependent on the type and concentration of salts added. The viscosity behavior of cationic poly(HCQNBMA)/NA is in contrast with polybetaines. An increase in KCl concentration causes the reduced viscosity of poly(HCQNBMA)/NA to decrease at constant poly(HCQNBMA)/NA concentration. The general shape of the surface tension versus logarithm of concentration curve for poly(HCQNBMA)/NA shows only a slow decrease with increasing polymer concentration upon addition of various salts. The surface tension increases in the series KF>KCl>KBr>KI in a given polymer concentration. When the naphthalene label was introduced into the poly(HCQNBMA), the behavior of the solution properties of the poly(HCQNBMA)/NA could be clearly defined in terms of fluorescence analysis. The quenching efficiency of NaI or CH 3 NO 2 was reduced with increasing KCl concentration arising from compacted conformation of polymer chains. A model of the interaction between poly(HCQNBMA)/NA and surfactant or salt in aqueous solution is proposed.

A new bis(ether anhydride), 1,1-bis[4-(3,4-dicarboxyphenoxy)phenyl] cyclododecane dianhydride (BDPCD), was prepared in three steps starting from nitrodisplacement of 4-nitrophthalonitrile with 2,2-bis(4-hydroxyphenyl) cyclododecane (BHPC), followed by alkaline hydrolysis of the dehydration of the resulting bis(ether diacid) (BCPPC) and subsequent dehydration of the resulting bis(ether diacid) (BAPPC). A series of new highly soluble poly(ether imide)s having tert-butyl substitutents, together with noncoplanar and pendent cardo groups were prepared from such bis(ether anhydride) (BDPCD) with various diamines by a conventional two-stage synthesis including the polyaddition and chemical cyclodehydration. The resulting poly(ether imide)s had inherent viscosities inthe range of 0.50-.0.86 dL.g -1 . The GPC measurement revealed that the polymers exhibited number-average and weight-average molecular weight up to 63 000 and 115 000, respectively. All the polymers showed typical amorphous diffraction patterns. All of the poly(ether imide)s showed excellent solubility and were readily dissolved in various solvents such as N-methyl-2-pyrrolidinone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), pyridine, cyclohexanone and tetrahydrofuran. Most of the polymers could be dissolved in chloroform as high as 30wt.-% concentration. These polymers had glass transition temperatures (T g ) in the range of 230-262°C. Thermogravimetric analysis (TGA) showed that all polymers were stable, with 10% weights loss recorded above 434°C and 407°C in nitrogen and air, respectively. These transparent, tough and flexible polymer films could be obtained by solution casting from the DMAc solution. These polymer films had tensile strengths in the range of 80-102 MPa and tensile moduli in the range of 1.7-2.0 GPa.

A new bis(ether anhydride), 3,3′,5,5′-tetramethyl-2,2-bis[4-(4-dicarboxyphenoxy)phenyl]propane dianhydride (3), was prepared in three steps: the nitro displacement of 4-nitrophthalonitrile with 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, the alkaline hydrolysis of the intermediate bis(ether dinitrile), and the subsequent dehydration of the resulting bis(ether diacid). A series of new highly soluble poly(ether imide)s with tetramethyl and isopropylidene groups were prepared from the bis(ether anhydride) 3 with various diamines by a conventional two-stage synthesis including polyaddition and chemical cyclodehydration. The resulting poly(ether imide)s had inherent viscosities of 0.54–0.73 dL g−1. Gel permeation chromatography measurements revealed that the polymers had number-average and weight-average molecular weights of up to 54,000 and 124,000, respectively. All the polymers showed typical amorphous diffraction patterns. All of the poly(ether imide)s showed excellent solubility and were readily dissolved in various solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide, N,N-dimethylformamide, pyridine, cyclohexanone, tetrahydrofuran, and even chloroform. Most of the polymers could be dissolved with chloroform concentrations as high as 30 wt %. These polymers had glass-transition temperatures of 244–282 °C. Thermogravimetric analysis showed that all polymers were stable, with 10% weight losses recorded above 463 °C in nitrogen. These transparent, tough, and flexible polymer films were obtained through solution casting from N,N-dimethylacetamide solutions. These polymer films had tensile strengths of 81–102 MPa and tensile moduli of 1.8–2.0 GPa. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2556–2563, 2002

A new bulky pendent bis(ether anhydride), 1,1-bis[4-(4-dicarboxyphenoxy)phenyl]-4-phenylcyclohexane dianhydride, was prepared in three steps, starting from the nitrodisplacement of 1,1-bis(4-hydroxyphenyl)-4-phenylcyclohexane with 4-nitrophthalonitrile to form bis(ether dinitrile), followed by alkaline hydrolysis of the bis(ether dinitrile) and subsequent dehydration of the resulting bis(ether diacid). A series of new poly(ether imide)s were prepared from the bis(ether anhydride) with various diamines by a conventional two-stage synthesis including polyaddition and subsequent chemical cyclodehydration. The resulting poly(ether imide)s had inherent viscosities of 0.50–0.73 dL g−1. The gel permeation chromatography measurements revealed that the polymers had number-average and weight-average molecular weights of up to 57,000 and 130,000, respectively. All the polymers showed typical amorphous diffraction patterns. All of the poly(ether imide)s showed excellent solubility in comparison with the other polyimides derived from adamantane, norbornane, cyclododecane, and methanohexahydroindane and were readily dissolved in various solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide, pyridine, cyclohexanone, tetrahydrofuran, and even chloroform. These polymers had glass-transition temperatures of 226–255 °C. Most of the polymers could be dissolved in chloroform in as high as a 30 wt % concentration. Thermogravimetric analysis showed that all polymers were stable up to 450 °C, with 10% weight losses recorded from 458 to 497 °C in nitrogen. These transparent, tough, and flexible polymer films could be obtained by solution casting from DMAc solutions. These polymer films had tensile strengths of 79–103 MPa and tensile moduli of 1.5–2.1 GPa. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2066–2074, 2002

Photophysical and solution properties of pyrene-labeled poly(3-dimethyl(methylmethacryloyl ethyl) ammonium propane sulfonate), poly(DMAPS/Py), were studied in terms of fluorescence emission measurement. The I E /I M was shown as a function of polymer concentration in deionized water. I E /I M value decreases with an increase in the salt concentration. The addition of surfactants to the aqueous solution of poly(DMAPS/Py) can either induce the mixed micelle of intra- polymer and its surrounding surfactants and/or mixed micelle of inter-polymers and their surrounding surfactants. Models of interactions between poly(DMAPS/Py) and surfactant or divalent salt in aqueous solution are proposed.

Single-walled carbon nanotubes (SWCNTs) demonstrate a high efficiency as optical elements for mode-locking in fiber lasers. A thin polymer film with dispersed nanotubes is a suitable approach to insert the element into the laser resonator. The main problem is that the polymer oxidative destruction temperature is much lower than that for SWCNTs. To form polymer–nanotube composites with a high threshold of thermal degradation, surviving under the relatively intense laser beams, a set of polyimides has been used. It has been shown that for the synthesized polyimides the temperature of degradation was in the range 500–530 °C, depending on the polymer. In the near-infrared range the polyimides were transparent, and the main absorption bands were detected at wavelengths less than 400 nm. A procedure of the fabrication of composite SWCNT/polyimide films was developed. The films were formed on transparent substrates, as quartz and glass slides.

A new hexafluoro-containing diamine monomer, 2,2-bis[4-(4-aminophenoxy)-3,5-dimethylphenyl]-bexafluoropropane (TBAPHP), was synthesized in three steps, starting from hexafluoroacetone sesquihydrate and 2,6-xylenol. The monomer was reacted with various aromatic dicarboxylic acids and tetracarboxylic dianhydrides to produce a series of polyamides and polyimides, respectively. The polyamides were prepared under Yamazaki reaction conditions. The polyimides were prepared by a two-stage procedure that included a ring-opening polyaddition yielding poly(amic acid)s, followed by a cyclodehydration to polyimides. The obtained polymers had inherent viscosities of 0.52-0.82 dL.g -1 . All of the polymers dissolved in polar solvents, such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide, and N,N-dimethyl-formamide. The polyimides derived from 4,4'-oxydiphthalic anhydride and 3,3',4,4'-benzophenonetetracarboxylic dianhydride exhibited an excellent solubility and were dissolved in cyclohexanone, pyridine, tetrahydrofuran, and chloroform. These polymers showed glass transition temperatures of 231-301 °C and decomposition temperatures at 10% weight loss ranging from 470 to 495 °C in nitrogen and from 473 to 505 °C in air. The tough and flexible polymer films obtained from solution casting showed tensile strengths of 78-96 MPa and tensile moduli of 2,0-2,4 GPa. Polymers containing methyl substituents had higher solubilities and T g values than those without methyl substituents. In addition, the bexafluoroisopropylidene containing polymers exhibited a higher solubility and thermal stability than those containing isopropylidene units. UV-visible absorption spectra revealed that the polyimides showed a better transparency than the polyamides.

In this work, two kinds of new cardo dicarboxylic acids containing a diphenylmethylene linkage and a pendant norbornyl group were prepared from p-fluorobenzonitrile and bis(4-hydroxphenyl)diphenylmethane and 2,2-bis(4-hydroxyphenyl)norbornane, respectively, via aromatic nucleophilic substitution reaction followed by hydrolysis. Several new polyamides were prepared by direct polycondensation of the dicarobxylic acids and various aromatic diamines. The polymers were produced with moderate to high inherent viscosities of 0.72-1.35 dL.g -1 . Nearly all the polymers were readily soluble in polar solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide, N,N-dimethylformamide, and dimethyl sulfoxide, as well as in less polar solvents such as pyridine and cyclohexanone, and also in tetrahydrofurane. All of the polymers were amorphous and the films had a tensile strength and tensile modulus above 82 MPa and 2.0 GPa. respectively. These polyamides had glass transition temperatures between 235-280°C and 10% weight loss temperatures in the range of 500-538 and 515-540°C in nitrogen and air atmosphere, respectively. Polyamides with a diphenylmethylene linkage showed higher thermal stability than those with a norbornyl group due to the presence of the phenyl groups.

A new kink diimide-dicarboxylic acid, 2,2-bis[4-(4-trimellitimidophenoxy)phenyl]diphenylmethane (BTPDM), was synthesized by the condensation reaction of bis[4-(4-aminophenoxy)phenyl]diphenylmethane (BAPDM) with trimellitic anhydride. A series of new poly(amide-imide)s were prepared by direct polycondensation of BTPDM and various aromatic diamines in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. The polymers were produced in high yield revealing moderate to high inherent viscosities of 0.80-0.89 dL.g -1 . Wide-angle X-ray diffractograms revealed that the polymers are amorphous. Most of the polymers exhibit good solubility and could be readily dissolved in various solvents such as NMP, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide, dimethyl sulfoxide, pyridine, cyclohexanone and tetrahydrofuran. These poly(amide-imide)s have glass transition temperatures between 244-248°C and show 10% weight loss in the range of 453-469°C under a nitrogen atmosphere. The tough polymer films, obtained by casting from DMAc solution, had tensile strengths ranging between 82 and 95 MPa and tensile moduli ranging between 1.7 and 1.9 GPa.

A new cardo diamine monomer, 1,1-bis [4-(4-aminophenoxyl) phenyl]-4-phenylcyohexane bearing a 4-phenylcyclohecylidene unit, was prepared in three steps from -4phenylcyoheanone. The monomer was reacted with various aromatic dicatboxilic acids and tetracarboxylic dianhydrides to produce novel polyamides and polyamides, respectively. The polyamides were prepared utizing Yamazaki reaction conditions with inherent viscosities of 0.62-0.98 dL . g -1 . The polyamides were prepared by a two-stage procedure that included a ringopening polyaddition to give poly(amic acids)s, followed by thermal or chemical cyclodehydration. By chemical cyclodehydratation, the obtained polyimides had inherent viscosities of 0.61-0.93 dL . g -1 . Most of the polymers dissolved in N,N-dimethylformamide dimethyl sulfoxide, pyridine, and cyclohexanone. These polymers showed glass transition temperatures between 225-312°C and decomposition temperatures at 10% weight loss temperatures ranging from 470-500°C and 480-510°C in nitrogen and air atmosphere, respectively. These tough and flexible polymer films had a tensile strenght of 81-124 MPa, an elongation at break of 8-21%, and tensile modulus of 2.0-2.8 GPa.

A new cardo diacid chloride, 1,1-bis-[4-(4-chlorocarboxyphenoxy)phenyl]-4-tert-butylcyclohexane (4), was synthesized from 1,1-bis-[4-(4-carboxyphenoxy)phenyl]-4-tert-butylcyclohexane in refluxing thionyl chloride. Subsequently, various new polyesters were prepared from 4 with various bisphenols by solution polycondensation in nitrobenzene using pyridine as a hydrogen chloride quencher at 150 °C. These polyesters were produced with inherent viscosities of 0.32–0.50 dL · g−1. Most of these polyesters exhibited excellent solubility in a variety of solvents such as N,N-dimethylformamide, tetrahydrofuran, tetrachloroethane, dimethyl sulfoxide, N,N-dimethylacetamide, N-methyl-2-pyrrolidinone, m-cresol, o-chlorophenol, and chloroform. These polymers showed glass-transition temperatures (Tg's) between 144 and 197 °C. The polymer containing the adamantane group exhibited the highest Tg value. The 10% weight loss temperatures of the polyesters, measured by thermogravimetric analysis, were found to be in the range of 426–451 °C in nitrogen. These cardo polyesters exhibited higher Tg's and better solubility than bisphenol A-based polyesters. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2951–2956, 2001

A series of new soluble poly(amide-imide)s were prepared from the diimide-dicarboxylic acid 2,2-bis[4-(4-trimellitimidophenoxy)phenyl]hexafluoropropane with various diamines by direct polycondensation in N-methyl-2-pyrrolidinone containing CaCl2 with triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.52–0.86 dL · g−1. The poly(amide-imide)s showed an amorphous nature and were readily soluble in various solvents, such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide, pyridine, and cyclohexanone. Tough and flexible films were obtained through casting from DMAc solutions. These polymer films had tensile strengths of 71–107 MPa and a tensile modulus range of 1.6–2.7 GPa. The glass-transition temperatures of the polymers were determined by a differential scanning calorimetry method, and they ranged from 242 to 279 °C. These polymers were fairly stable up to a temperature around or above 400 °C, and they lost 10% of their weight from 480 to 536 °C and 486 to 537 °C in nitrogen and air, respectively. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3498–3504, 2001

Surface modification of argon plasma–pretreated low-density polyethylene (LDPE) film via UV-induced graft copolymerization with a fluorescent monomer, (pyrenyl)methyl methacrylate (Py)MMA, was carried out. The chemical composition and morphology of the (Py)MMA-graft-copolymerized LDPE [(Py)MMA-g-LDPE] surfaces were characterized, respectively, by X-ray photoelectron spectroscopy (XPS) and by atomic force microscopy (AFM). The concentration of the surface-grafted (Py)MMA polymer increased with Ar plasma pretreatment time and UV graft copolymerization time. The photophysical properties of the (Py)MMA-g-LDPE surfaces were measured by fluorescence spectroscopy. After graft copolymerization with the fluorescent monomer, the surface of the LDPE film was found to have incorporated new and unique functionalities. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1526–1534, 2001

A new dicarboxylic acid containing a diphenylmethylene linkage, bis[4-(4-carboxyphenoxy)phenyl]diphenylmethane (BCAPD), was prepared from bis(4-hydroxphenyl)diphenylmethane and p-fluorobenzonitrile via an aromatic nucleophilic substitution reaction followed by hydrolysis. A series of novel polyamides were prepared by the direct polycondensation of BCAPD and various aromatic diamines. The polymers were produced with moderate to high inherent viscosities of 0.80–0.85 dL g−1. Nearly all the polymers were readily soluble in polar solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide, N,N-dimethylformamide, and dimethyl sulfoxide, in less polar solvents such as pyridine and cyclohexanone, and in tetrahydrofuran. All the polymers were amorphous, and the polyamide films had a tensile strength and a tensile modulus greater than 80 MPa and 2.0 GPa, respectively. These polyamides had glass-transition temperatures between 249 and 274 °C, and their temperatures at a 10% weight loss were 477–538 and 483–540 °C in nitrogen and air atmospheres, respectively. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1156–1161, 2001

A dicarboxylic acid monomer, 5-phthalimidoisophthalic acid, containing a phthalimide pendent group was prepared by the condensation of 5-aminoisophthalic acid and phthalic anhydride in glacial acetic anhydride. The monomer was reacted with various aromatic diamines to produce polyamides using triphenyl phosphite and pyridine as condensing agents. These polyamides were produced with inherent viscosities of 0.64-1.14 dL g 1 . All the polymers, characterized by wide-angle X-ray diffraction, revealed an amorphous nature resulting from the presence of the bulky pendent group. These polyamides exhibited excellent solubility in a variety of solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide, dimethyl sulfoxide, pyridine, and cyclohexanone. These polyamides showed glass-transition temperatures (T g 's) between 247 and 273 °C (by DSC) and 248 and 337 °C (by a dynamic mechanical analyzer). The thermogravimetric analytic measurement revealed the decomposition temperature at 10% weight-loss temperatures (Td 10 ) ranging from 442 to 530 °C in nitrogen. The polyamides containing phthalimide groups exhibited higher T g and Td 10 values than those having no phthalimide groups. Transparent, tough, and flexible films of these polyamides could be cast from the DMAc solutions. These casting films had tensile strengths ranging from 81 to 126 MPa, elongations at break ranging from 7 to 13%, and tensile moduli ranging from 2.0 to 2.9 GPa.

A new cardo diamine monomer, 1,1-bis[4-(4-aminophenoxy)phenyl]-4-tert-butylcyclohexane containing tert-butylcyclohexylidene units was prepared in three steps from 4-tert-butylcyclohexanone. The monomer was reacted with various aromatic dicarboxylic acids and tetracarboxylic dianhydrides to produce polyamides and polyimides, respectively. All the polymers, characterized by X-ray diffraction, are amorphous. These cardo polymers exhibit good solubility in a variety of solvents. Almost all polymers are soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), pyridine, and even in tetrahydrofuran (THF) and cyclohexanone. The polymers show glass transition temperatures between 244-310°C. and decomposition temperatures at 10% mass loss ranging from 486-526°C in nitrogen. The tough and flexible polymer films have tensile strength of 77-137 MPa, elongations at breaks of 5-14% and tensile moduli of 2.0-2.6 GPa.

Four polyimides (PIa-PId) containing 4,4′-hexafluoroisopropylidene-bisphthalic anhydride (6FDA) units in the backbone were prepared via one-step synthesis. The effects of different doses of gamma radiation from a cobalt-60 source are studied. The irradiated and the unirradiated polyimides are characterized by using tensile strength, infrared (IR), viscosity, differential scanning calorimeter (DSC), and gel permeation chromatography (GPC). All polyimides show the increase of tensile strength and elongation at low doses (>350 Mrad). The molecule weights decrease as the irradiation doses increase. All samples showed a drastic degradation of the mechanical and thermal properties at doses above 1400 Mrad. Samples irradiated at a dose of 2800 Mrad were completely brittle. The major difference of the radiation effect of the polyimides depends largely on their structural differences. PId with an extra hexafluoroisopropylidene moiety is most sensitive to irradiation at high doses.

Different types of sulfobetaines and their corresponding cationic monomers and polymers derived from N,N-dialkylamino phenyl methacrylamide have been synthesized for this study. Comparing the chemical shifts in 1 H and 13 C NMR of the methylene groups in the cationic monomers and betaines reveal that the respective methylene groups are clearly distinguishable from each other. Results obtained from the intrinsic viscosity for zwitterionic poly(DEMAPhAPS) are opposite to that for the corresponding cationic poly(DEMMAPhAMS).

A new dicarboxylic acid monomer, 1,1-bis[4-(4-carboxyphenoxy)phenyl]-4-tert-butylcyclohexane, bearing a pendent tert-butylcyclohexylidene group was prepared in three steps from 4-tert-butylcyclohexanone. The monomer was reacted with various diamines to produce a series of new polyamides with triphenyl phosphite and pyridine as condensing agents. These polyamides were produced with inherent viscosities of 0.74 to 1.02 dL g−1. All the polymers were characterized by X-ray diffraction that revealed this amorphous nature. These polymers exhibited excellent solubility in a variety of solvents. Almost all the polymers could be dissolved in N-methyl-2-pyrrolidinone, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide, dimethyl sulfoxide, pyridine, and even in tetrahydrofuran and cyclohexanone. These polymers showed glass-transition temperatures between 223 and 256 °C and decomposition temperatures at 10% weight loss ranging from 468 to 491 °C and 469 to 498 °C in nitrogen and air atmospheres, respectively. Transparent, tough, and flexible films of these polymers were cast from the DMAc solutions. These polymer films had tensile strengths ranging from 76 to 99 MPa, elongations at break from 7 to 19%, and initial moduli from 2.1 to 2.7 GPa. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 797–803, 2000