Search

A novel method for preparing composites of polyimides (PI) laminated to poly(tetrafluoroethylene) (PTFE) films is reported. PI/PTFE composites were developed through thermal imidization of poly(amic acid) (PAA) precursors on surface-modified PTFE films. Surface modification of PTFE films was carried out via Ar plasma pretreatment of the films, followed by UV-induced graft copolymerization with glycidyl methacrylate (GMA). The surface composition and topography of the graft copolymerized PTFE films and the delaminated PI and PTFE surfaces were characterized by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), respectively. The adhesion strengths of the PI (imidized PAA) on the GMA graft copolymerized PTFE films were evaluated as a function of various thermal imidization schedules. The adhesion reliability of the PI/PTFE composites was tested by a series of hydrothermal cycles. The development of strong Tpeel adhesion strengths of about 8 N/cm with excellent reliability for the PI/PT...

A zwitterionic polymer—poly-3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate (PDMAPS)—was synthesized and its complexation behaviors with polyanion: poly-2-acrylamido-2-methyl propane sulfonic acid (PAMPS); and polycation: poly-3-acryloylamino propyl trimethyl ammonium chloride (PDMAPAA-Q); or: x , y -ionene bromides ( x =3,6; y =3,4) have been studied. One of the characteristic features of these complexes is that they are soluble, in spite of the abolishment of positive or negative charge of PDMAPS after the complexation and is able to exhibit UCST depending on the concentration and the mixing molar ratio. It was found that PDMAPS–PAMPS complex dramatically increases the viscosity to give a network structure through electrostatic interaction extensively decreasing the UCST, while the PDMAPS–polycation complex first decreases, but then increases the UCST without forming the network. The mechanism of different behaviors of these complexes has been discussed.

Interaction between naphthalene-labeled poly(hydrochloride quaternized 2-norbornene-5-methyleneamine), poly(HCQNBMA)/NA (luminophore), and quencher, emulsifier or coemulsifier in the aqueous or microemulsion media was studied by using steady-state fluorescence measurements. Fluorescence experiments were carried out with poly(HCQNBMA)/NA dissolved in the aqueous solutions of ionic and nonionic emulsifiers, emulsifier/n-hexane/water microemulsion (A) and emulsifier/n-hexane/1-pentanol/water microemulsion (B), respectively. The intensity of fluorescence emission of poly(HCQNBMA)/NA was much higher in the aqueous phase than in microemulsion. Furthermore, the aqueous solution of ionic emulsifier increased the monomer emission. The increase in the monomer emission can be ascribed to the shielding of the naphthalene (NA) groups by SDS micelles. This separates NA groups from each other, which depresses the deactivation of excited states. The strong decrease in monomer emission within the microemulsion media probably results from the elongated conformation structure of the polymer molecule, and higher conformation freedom of NA groups, which increases interaction between the probe and the quencher. The formation of nonfluorescence clusters is not ruled out. The quenching of NA emission by nitromethan (NM) is much stronger in microemulsion than in the aqueous phase, and the quenching is more pronounced for the low molecular weight 2-norbornene-5-methoxylnaphthalene (NBMNA) than for its polymer. The extent of penetration of reactants into the interfacial layer governs quenching of hydrophobic NA probe by hydrophilic quencher. Furthermore, the quenching events are connected with the thickness and density of the interfacial layer, as well as its charge. The addition of coemulsifier (1-pentanol) increases the total surface area of the microdroplets, the entry rate of reactants into the microdroplets, and the interaction of hydrophobic and hydrophilic reactants. The quenching events are more pronounced in the close packed o/w interfacial layer than in the loosely packed one. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 101–114, 2001

A series of new polyesters was prepared from terephthaloyl (or isophthaloyl) chloride acid with various cardo bisphenols on solution polycondensation in nitrobenzene using pyridine as hydrogen chloride quencher at 150 °C. These polyesters were produced with inherent viscosities of 0.32–0.49 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, and o-chlorophenol. The polyesters containing cardo groups including diphenylmethylene, tricyclo[5.2.1.02,6]decyl, tert-butylcyclohexyl, phenylcyclohexyl, and cyclododecyl groups exhibited better solubility than bisphenol A–based polyesters. These polymers showed glass transition temperatures (Tg's) between 185 °C and 243 °C and decomposition temperatures at 10% weight loss ranging from 406 °C to 472 °C in nitrogen. These cardo polyesters exhibited higher Tg's and better solubility than bisphenol A-based polyesters. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4451–4456, 2000

A novel polyaryloxydiphenylsilane was synthesized successfully by solution polycondensation of 2,2′-dimethyl-biphenyl-4,4′-diol with diphenyldichlorosilane and the catalyst triethylamine in toluene at 80 °C. Polymers with a relatively high inherent viscosity and yield were obtained when the reactions were carried out in aromatic and lipophilic solvents. The novel polyaryloxydiphenylsilane was soluble in chlorinated aliphatic hydrocarbons such as methylene chloride and chloroform as well as in polar solvents such as dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide and also in some common organic solvents such as benzene and toluene. However, it was insoluble in both aliphatic hydrocarbons as well as in alcoholic solvents. The polyaryloxydiphenylsilane began losing weight around 400 °C under a nitrogen atmosphere, and the 10% weight-loss temperature was 473 °C. The glass-transition temperature of the polyaryloxydiphenylsilane was 102 °C. The glass transition could be lowered by the copolymerization technique with 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane as an aromatic diol comonomer. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4591–4595, 1999

This paper presents the synthesis and characterization of polyimides, which contain a 4,4'-hexafluoroisopropylidene-bisphthalic anhydride (6FDA) unit in the backbone. These polyimides are a result of the use of the traditional method of "one step". The reactions occur between equimolar of a dianhydride and an aromatic diamine in presence of the solvent dimethylacetamide (DMAc), then cyclo-dehydrided by adding the acetic anhydride and pyridine. In this work, the 6FDA was used as the dianhydride and four different diamines were investigated: 3,3',5,5'-Tetramethyl-2,2- bis[4-( 4-aminophenoxy) phenyl] propane; 2,2-bis[4-(4-aminophenoxy)-phenyl] hexafluoropropane; 1,3-bis(4-aminophenoxy)benzene and 2,2'-dimethyl-4,4'-bis(4-aminophenoxy)biphenyl. The four polyimides (PA, PB, PC and PD) were characterized by tensile strength, infrared, inherent viscosity, Differential Scanning Calorimeter (DSC) to get the glassy transition temperature (Tg) and Gel Permeation Chromatograph (GPC) to obtain the average molecular weight (Mn).

A simple technique of thermal graft copolymerization of 1-vinyl imidazole (VIDZ) on pristine and argon plasma pretreated fluorinated polyimide (FPI) films with simultaneous lamination of copper foils was demonstrated. The simultaneous thermal grafting and lamination process was carried out in the temperature range of 80–140°C under atmospheric conditions and in the complete absence of a polymerization initiator. Three different FPI samples of different chemical structures were employed in the present study. An optimum T-peel strength about 15 N/cm was achieved for the copper/FPI laminate. The adhesion strength, however, decreased with increasing fluorine content in the FPI film. The onset of cohesive failure occurred in the FPI film for assemblies with T-peel strength greater than 6 N/cm. The T-peel strengths are reported as a function of the argon plasma pretreatment time of the FPI films and thermal lamination temperature. The adhesion strengths were compared to that of the similarly prepared copper/polyimide (Kapton HN) laminate. Time-dependent water contact angle (Θ) measurements indicated that the surfaces of FPI films are significantly more hydrophobic and more resistant to water diffusion or hydration than the Kapton HN films. The surface compositions of the pristine FPI films, as well as the delaminated FPI films and copper foils were studied by X-ray photoelectron spectroscopy. The thickness of the graft VIDZ polymer layer was in the order of 200 nm, as derived from the cross-sectional view of the scanning electron micrograph. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1478–1489, 1999

2-Norbornene-5-methylphthalimide (NBEPI) was prepared to synthesize an amino group containing poly(norbornene) via living ring-opening metathesis polymerization (ROMP) using a well-defined catalyst {Cl 2 Ru(CHPh)[P(C 6 H 11 ) 3 ] 2 }. The resulting poly(NBEPI) was of high molecular weight and had a reasonably narrow molecular weight distribution (Mn = 298,900 and PDI = 1.22). The glass transition temperature (T g ) of poly(NBEPI) is 140°C. The 10% decomposition temperature of poly(NBEPI) is 410°C. Hydrazinolysis of poly(NBEPI) gave poly(2-norbornene-5-methylamine), poly(NBEMA). Though insoluble in almost all organic solvents, poly(NBEMA) becomes soluble in water after quaternization of the amine groups by gaseous HCl, Because of the living nature of the polymerization of NBEPI, poly(NBEMA) is reasonably linear and has a well-controlled molecular weight. The hydrogenation of poly(NBEPI) by diimide generated in situ from p-toluenesulfonylhydrazide decreased the T g but increased thermal stability.

Surface thermal graft copolymerization with concurrent lamination was carried out between two argon plasma-pretreated polytetrafluoroethylene (PTFE) films in the presence of aqueous zwitterionic solutions of N,N-dimethyl-N-methacrylamidopropyl-N-(3-sulfopropyl)ammonium betain (DMASAB), N,N-dimethyl(methacryloylethyl)ammonium propansulfonate (DMAPS), and 1-(3-sulfopropyl)-2-vinylpyridinium betaine (SVPB), as well as an aqueous ionic solution of potassium-2-sulfopropylacrylate (SPA) and potassium-2-sulfopropyl methacrylate (SPM), under atmospheric conditions and in the complete absence of an added initiator and system degassing. The lap shear adhesion strength between the PTFE films from simultaneous grafting and lamination depended on the argon plasma pretreatment time of PTFE films, the thermal lamination temperature, the concentration of the monomer solution, and the ionic nature of the grafted chains. Lap shear adhesion strength greater than 120 N/cm2 and exceeding the yield strength of the PTFE substrate used could be readily obtained in most PTFE/zwitterion/PTFE assemblies after simultaneous thermal graft copolymerization and lamination. The chemical compositions of the graft-copolymerized surfaces were studied by X-ray photoelectron spectroscopy (XPS). © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 816–824, 1999

A poly(o-trimethylsilylphenylacetylene) [poly(o-TMSPA)] initiated by a tungsten carbene complex was investigated under various conditions. The molar mass of poly(o-TMSPA) increases with increasing the polymerization temperature and decreasing the initiator concentration. The X-ray diffraction measurements show that poly(o-TMSPA) has an amorphous structure. The water molecules preferentially permeate through the poly(o-TMSPA) membranes. The effects of feed compositions, degree of swelling, and the molecular size of alcohols on the pervaporation performances were investigated. The separation factor and the permeation rate increase with increasing ethanol concentration in the feed. The diffusivity contributes to a major part to selective transport. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 647–654, 1999

A new cardo diimide-dicarboxylic acid, 8,8-bis[4-(4-trimellitimidophenoxy)phenyl]tricyclo-[5.2.1.0 2,6 ]decane (BTPTD), containing an ether linkage and a tricyclo[5.2.1.0 2,6 ]decane group was synthesized by condensation reaction of 8,8-bis[4-(4-aminophenoxy)phenyl]tricyclo[5.2.1.0 2,6 ]decane with trimellitic anhydride. A series of new cardo polyamide-imides were prepared by direct polycondensation of BTPTD with various aromatic diamines in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. The polymers were produced with high yield and moderate to high inherent viscosities, i.e., of 0.73-1.36 dL g -1 . Nearly all polymers are readily soluble in polar aprotic solvents such as NMP, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide, dimethyl sulfoxide as well as less polar solvents such as pyridine, γ-butyrolactone, and tetrahydrofuran. These polymers were solution-cast from DMAc solution into transparent, flexible, and tough films except for polymers 4a and 4b. Wide-angle X-ray measurement revealed that all polymers were amorphous. These polyamide-imides have glass transition temperatures between 250-290°C and 5% weight loss temperatures in the range of 445 to 491 and 462 to 490°C in nitrogen and air atmosphere, respectively. The polymer films have a tensile strength range of 77 to 87 MPa, an elongation at break range of 3 to 9%, and a tensile modulus range of 2.2 to 2.8 GPa.

A new kink diamine, bis[4-(4-aminophenoxy)phenyl]diphenylmethane (BAPDM), bearing diphenylmethylene linkage was reacted with various aromatic dianhydrides to prepare the corresponding new polyimides via the poly(amic acid) precursors and thermal or chemical imidization. The poly(amic acid)s were produced with moderate to high inherent viscosities of 0.96-1.68 dl g -1 . All the poly(amic acid)s films could be obtained by solution-cast from N,N-dimethylacetamide (DMAc) solutions and thermally converted into transparent, flexible, and tough polyimide films. The wide-angle X-ray diffraction diagrams revealed that all the polyimides showed amorphous character. These polyimide films had a tensile strength of range 75-147 MPa and tensile modulus of 2.4-3.0 GPa. Polymers PI-3, PI-5 and PI-6 showed excellent solubility in a variety of solvents such as N-methyl-2-pyrrolidinone (NMP), DMAc, N,N-dimethylformamide (DMF), dimethyl sulfoxide, γ-butyrolactone, pyridine, cyclohexanone and tetrahydrofuran. These polyimides had glass transition temperatures between 248-331°C. The thermogravimetric analysis revealed that these polyimides exhibited good thermal stability with polymer decomposition temperature in excess of 500°C in nitrogen and air atmosphere. They had 10% weight loss temperatures in the range of 542-564 °C and 549-572 °C in nitrogen and air, respectively.

A new cardo diamine monomer, 5,5-bis[4-(4-aminophenoxy)phenyl]-4,7-methanohexahydroindane (II), was prepared in two steps with high yield. The monomer was reacted with six different aromatic tetracarboxylic dianhydrides in N,N-dimethylacetamide (DMAc) to obtain the corresponding cardo polyimides via the poly-(amic acid) precursors and thermal or chemical imidization. All the poly(amic acid)s could be cast from their DMAc solutions and thermally converted into transparent, flexible, and tough polyimide films which were further characterized by x-ray and mechanical analysis. All of the polymers were amorphous and the polyimide films had a tensile strength range of 89-123 MPa, an elongation at break range of 6-10%, and a tensile modulus range of 1.9-2.5 GPa. Polymers V c , V e , and V f exhibited good solubility in a variety of solvents such as N-methyl-2-pyrrolidinone (NMP), DMAc, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), pyridine, y-butyrolactone, and even in tetrahydrofuran and chloroform. These polyimides showed glass-transition temperatures between 274 and 299°C and decomposition temperatures at 10% mass loss temperatures ranging from 490 to 521°C and 499 to 532°C in nitrogen and air atmospheres, respectively.

A new diamine, 2,2-bis[4-(4-aminophenoxy)phenyl]norbornane (BAPN), containing both ether and norbornane cardo groups, was synthesized in three steps started from norcamphor. A series of cardo polyamides were obtained by the direct polycondensation of BAPN and various aromatic dicarboxylic acids in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. Polyamides had inherent viscosities in the range of 0.82–1.58 dL g−1, and were readily soluble in polar aprotic solvents such as NMP, N,N-dimethylacetamide (DMAc) and N,N-dimethylformamide and dimethyl sulfoxide. These polymers were cast in DMAc solution into transparent, flexible, and tough films that were further characterized by X-ray and mechanical analysis. All the polymers were amorphous, and the polyamide films had a tensile strength range of 71–89 MPa, an elongation at break range of 5–9%, and a tensile modulus range of 2.0–2.3 GPa. Polyamides showed glass transition temperatures in the range of 256–296°C as measured by DSC and thermogravimetric analysis indicated no weight loss below 450°C in nitrogen and air atmosphere. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2791–2794, 1999

A series of novel soluble poly(amide-imide)s were prepared from the diimide-dicarboxylic acid, 2,2-bis[N-(4-carboxyphenyl)-phthalimidyl]hexafluoropropane, with various diamines by the direct polycondensation in N-methyl-2-pyrrolidinone containing CaCl 2 using triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.78-1.63 dL g -1 . The polymers were amorphous and readily soluble in aprotic 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 y-butyrolactone, and also in tetrahydrofuran. The polymer films had tensile strength of 84-129 MPa, an elongation at break range of 6-22%, and a tensile modulus range of 2.0-2.7 GPa. The glass transition temperatures of the polymers were determined by DSC method and they were in the range of 240-282°C. These polymers were fairly stable up to a temperature around or above 400°C, and lose 10% weight in the range of 450-514°C and 440-506°C in nitrogen and air, respectively.

A novel bismaleimide, 2,2′-dimethyl-4,4′-bis(4-maleimidophenoxy)biphenyl, containing noncoplanar 2,2′-dimethylbiphenylene and flexible ether units in the polymer backbone was synthesized from 2,2′-dimethyl-4,4′-bis(4-aminophenoxy)biphenyl with maleic anhydride. The bismaleimide was reacted with 11 diamines using m-cresol as a solvent and glacial acetic acid as a catalyst to produce novel polyaspartimides. Polymers were identified by elemental analysis and infrared spectroscopy, and characterized by solubility test, X-ray diffraction, and thermal analysis (differential scanning calorimetry and thermogravimetric analysis). The inherent viscosities of the polymers varied from 0.22 to 0.48 dL g−1 in concentration of 1.0 g dL−1 of N,N-dimethylformamide. All polymers are soluble in N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, pyridine, m-cresol, and tetrahydrofuran. The polymers, except PASI-4, had moderate glass transition temperature in the range of 188°–226°C and good thermo-oxidative stability, losing 10% mass in the range of 375°–426°C in air and 357°–415°C in nitrogen. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 279–286, 1999

A series of new soluble polyamides having isopropylidene and methyl-substituted arylene ether moieties in the polymer chain were prepared by the direct polycondensation of 3,3',5,5 -tetramethyl-2,2-bis [4-(4-carboxyphenoxy)phenyl] propane and various diamines in N-methyl-2-pyrrolidinone (NMP) containing CaCl 2 using triphenyl phosphite and pyridine as condensing agents. Polymers were produced with moderate to high inherent viscosities of 0.85-1.47 dL g -1 while the weight-average molecular weight and number-average molecular weight were in the range of 86,700-259,000 and 43,300-119,000, respectively. All the polymers were readily dissolved in polar aprotic solvents such as NMP, N,N-dimethylacetamide, and N,N-dimethylformamide, as well as less polar solvents such as m-cresol and pyridine, and even soluble in tetrahydrofuran. These polymers were solution-cast into transparent, flexible and tough films. All of the polymers were amorphous and the polyamide films had a tensile strength range of 82-122 MPa, an elongation at break range of 6-18%, and a tensile modulus range of 2.0-2.8 GPa. These polyamides had glass transition temperatures between 233-260°C and 10% weight loss temperatures in the range of 450-489 and 459-493°C in nitrogen and air atmosphere, respectively.

The copolymers derived from zwitterionic DMAPAMAIPS and hydrophobic monomer (AdMAI or NaMAI) were studied in terms of the surface tension, viscometrics, and photophysical measurements. The surface tension of poly(DMAPAMAIPS) was shown to be larger than that of both the copolymer [poly(DMAPAMAIPS/NaMAI)] with an aromatic hydrophobic residue (naphthalene group) and [poly(DMAPAMAIPS/AdMAI)] with an aliphatic hydrophobic residue (adamantane group). The copolymer [poly(DMAPAMAIPS/NaMAI)] has a larger surface activity than that of [poly(DMAPAMAIPS/AdMAI)]. The reduced viscosity of the copolymers revealed that both zwitterionic and hydrophobic associations were important in polymer aggregation. The aromatic hydrophobic units of the copolymer [poly(DMAPAMAIPS/NaMAI)] were more strongly associated than the units of aliphatic hydrophobic copolymer [poly(DMAPAMAIPS/AdMAI)] due to the stronger hydrophobic aggregation of naphthyl groups. The fluorescence experiment showed that when the hydrophobic adamantyl group was ...

The two new functional monomers, UMAI and UDMAI, having amide groups were prepared on reaction of methacryloyl isocyanate (MAI) with urea at low temperature. The monomers thus obtained were characterized by elemental analysis, as well as infrared, ultraviolet, 1H and 13C-NMR (nuclear magnetic resonance) spectra. Radical polymerization of UMAI monomer was studied in terms of the rate of polymerization, solvent effect, thermal properties, solubility, and polymer modifications. The rate of polymerization for UMAI is larger than that of polymerization for bisphenol A-MAI (BPA-MAI), irrespective of the polymerization method. The rate of thermal polymerization of UDMAI was three times that of UMAI. Copolymerization of UMAI (M1) and methyl methacrylate (M2) in dimethylsulfoxide (DMSO) at 90°C also proceeded. The monomer reactivity ratio was calculated to be r1 = 0.28 ± 0.05, r2 = 3.50 ± 0.08, according to the Kelen-Tudos method. The thermal properties of polyUMAI (PUMAI) for glass transition temperature (Tg) and 10% weight loss temperature (T) could be enhanced by reaction with sulfonyldiphathalic anhydride. The solubility of PUMAI could be improved by introducing N-alkylation because of reducing the association of hydrogen bonds. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1789–1796, 1999

A series of new soluble poly(amide-imide)s were prepared from the diimide-dicarboxylic acid, 3,3′,5,5′-tetramethyl-2,2-bis[4-(4-trimellitimidophenoxy)phenyl]propane (TBTPP), with various diamines by the direct polycondensation in N-methyl-2-pyrrolidinone using triphenyl phosphite and pyridine as condensing agents. The new diimide-dicarboxylic acid TBTPP bearing isopropylidene and methyl-substituted arylene ether units was synthesized by the condensation reaction of 3,3′,5,5′-tetramethyl-2,2-bis[4-(4-aminophenoxy)phenyl]propane with trimellitic anhydride. All the polymers were obtained in quantitative yields with inherent viscosities of 0.58-1.03 dl g−1. The polymers were amorphous and most of them were readily soluble in aprotic polar solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide, and N,N-dimethylformamide, as well as in less polar solvents such as dimethyl sulfoxide, m-cresol, pyridine and γ-butyrolactone, and also even in tetrahydrofuran. The glass transition temperatures of the polymers were determined by the differential scanning calorimetry (DSC) method and were in the range 240–278°C. These polymers were stable up to 450°C and lose 10% weight in the range of 454–484°C and 448–482°C in nitrogen and oxygen, respectively. The polymer films had a tensile strength range of 98–122 MPa and a initial modulus range of 2.7–3.8 GPa.

In this work, we synthesized a new diamine containing a pendant adamantane group and a flexible aryl ether unit, 2,2-bis[4-(4-aminophenoxy)phenyl]adamantane (BAPA) in three steps starting from 2-adamantanone. A series of new polyamides having inherent viscosities of 0.72-0.90 dL.g -1 were prepared by direct polycondensation with aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. All polymers revealed an amorphous nature and were almost readily soluble in a variety of polar solvents. The glass transition temperature of these polyamides range from 254-294°C. The polyamides remain fairly stable up to a temperature around 450°C and lose 10% weight between 490 and 524°C in nitrogen atmosphere. A series of new polyimides were also synthesized from BAPA and various aromatic tetracarboxylic dianhydrides by the conventional two-step method. The inherent viscosities of polyimides were in the range of 0.66-0.77 dL.g -1 . The polyimides are amorphous and have glass transition temperatures between 276 and 310°C. Thermogravimetric analyses demonstrated that almost all polymers are stable up to 450 °C, and the 10% weight loss temperatures were recorded in the range of 515 to 541°C in nitrogen.

Radical polymerization of the methacryloyl isocyanate containing 1-adamantanol (Ad-MAI) with AIBN in different solvents at 60°C was investigated. It is observed that polymerization is slower in polar solvents than in nonpolar ones. The rate of polymerization for Ad-MAI was found to be slower than those of Adph-MAI and MMA both in photopolymerization and in thermal polymerization. Copolymerization of Ad-MAI (M1) with styrene (M2) in benzene was studied at 60°C. The monomer reactivity ratio was calculated to be r1=1.53 and r2=0.76 according to the method of Fineman-Ross. The prominent glass transition temperature for poly(Ad-MAI) was observed at 142°C from global TSC spectrum.

Two aromatic polyamide membranes were synthesized by direct polycondensation of 5-t-butyl isophthalic acid with 2,2-bis[4-(4-aminophenoxy)phenyl]hexfluoropropane, (F-aramide), and with 2,2-bis[4-(4-aminophenoxy)- phenyl]propane, (H-aramide), in a solution containing triphenyl phosphite, pyridine and N -methyl-2-pyrrolidinone. The effects of feed composition, feed temperature, and the molar volume of the feed alcohol on pervaporation performance were investigated. The separation factor and the permeation rate increased with increasing ethanol concentration in the feed for both aromatic polyamide membranes. The separation factor of the H-aramide membrane was higher than that of the F-aramide for pervaporation of water/ethanol solution. For the H-aramide membrane, a separation factor of 60 and a permeation rate of 293 g m −2 h −1 were obtained when the concentration in the feed was 90 wt% and the feed temperature was maintained at 25°C.

A new diamine, 1,1-bis[4-(4-aminophenoxy)phenyl] cyclododecane (BAPCD), bearing flexible ether and bulky pendant cyclododecylidene groups was prepared in three steps from cyclododecanone. The monomer was reacted with six conventional aromatic dianhydrides in N,N-dimethylacetamide (DMAc) to obtain the corresponding new polyimides via the poly(amic acid) precursors and thermal or chemical imidization. The poly(amic acid)s obtained had inherent viscosities ranging from 1.10–1.42 dl g−1. All the poly(amic acid)s could be cast from DMAc solutions and thermally converted into transparent, flexible, and tough polyimide films, except for polymer Va which was derived from pyromellitic dianhydride. X-ray diffractograms of polyimides indicated all polymers were amorphous except the polymer Va. Polyimides derived from 4,4′-sulfonyldiphthalic anhydride and 4,4′-hexafluoroisopropylidenediphathalic anhydride exhibited excellent solubility in various polar solvents. These polymers showed glass transition temperatures between 259°C and 276°C, and decomposition temperatures at initial and 10% mass loss ranging from 430°C to 483°C and from 504°C to 526°C in nitrogen, respectively. The polyimide films, except Va, had a tensile strength in the range 76–112 MPa and a tensile modulus in the range 2.1–3.5 GPa.

Photolysis of bisphenol-based polyurethanes, using bisphenols A, S, and AF with methylene diphenyl diisocyanate (MDI), has been shown by the observed changes in fluorescence spectra, reduced viscosity, and UV absorbance. Analysis of the fluorescence spectra of model compounds and polymers showed that para-photo-Fries and cleavage-type products were the major components formed during photolysis. The reduced viscosity and UV absorbance changes are consistent with a two-step photodegradation process. The reduced viscosity changes indicate that oxygen inhibition on the cleavage process is more significant for bisphenol S-based polyurethanes than for bisphenol A- and bisphenol AF-based polyurethanes.

In this work, a new adamantane-type cardo dicarboxylic acid containing ether group, 2,2-bis[4-(carboxyphenoxy)phenyl]-adamantane (BCAPA), was prepared from 2,2-bis(4-hydroxyphenyl)adamantane and p-fluorobenzonitrile via the aromatic nucleophilic substitution reaction followed by hydrolysis. A series of new polyamides were prepared by the direct polycondensation of BCAPA and various diamines utilizing Yamazaki reaction conditions. The polymers were produced with moderate to high inherent viscosities of 0.65–1.06 dl g–1. The polymers, except polymers PA4, PA7 and PA8, exhibited weight-average molecular weight and number-average molecular weight in the range of 57 400–106 000 and 32 500–58 200, respectively. Nearly all the polymers were readily soluble in polar solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide, and N,N-dimethylformamide, as well as less polar solvents such as dimethyl sulfoxide, pyridine and γ-butyrolactone, and also in tetrahydrofuran. All of the polymers were amorphous and the polyamide films had a tensile strength and tensile modulus above 86 MPa and 2.0 GPa. These polyamides had glass transition temperatures between 254–292°C and 10% weight loss temperatures in the range of 450–507 and 481–516°C in nitrogen and air atmosphere, respectively.

A new diamine containing sulfone and oxyethylene unit, 2,2-bis[4-[2-(4-aminophenoxy)ethoxy]phenyl]sulfone (BAEPS), was used as a monomer with various aromatic tetracarboxylic dianhydrides to synthesize polyimides via a conventional two-step procedure. The diamine was prepared through the aromatic nucleophilic substitution of bis[4-(2-hydroxyethoxy)phenyl]sulfone with p-fluoronitrobenzene in the presence of potassium carbonate, followed by catalytic reduction with hydrazine monohydrate/Pd–C. Depending on the dianhydrides used, the poly(amic acid)s obtained had inherent viscosities of 0.90–1.32 dl/g. All the poly(amic acid)s were cast from the N,N-dimethylacetamide solution and thermally converted into transparent, flexible and tough polyimide films. The polyimide films had a tensile strength range of 74–151 MPa and tensile modulus between 1.9 and 3.0 GPa. Almost all the polymers were amorphous except for that derived from dianhydride pyromellitic dianhydride (PMDA). The polyimide derived from 4,4′-hexafluoro-isopropylidenediphathalic anhydride exhibited excellent solubility in various organic solvents. These polyimides had moderate glass transition temperatures of between 185 and 222°C. The PMDA-based polyimide exhibited melting temperature at 413°C. The 10% mass loss temperatures of the polyimides were recorded in the range of 445–468 and 433–452°C in nitrogen and air atmosphere, respectively. Copyright © 1999 John Wiley & Sons, Ltd.

The brittle property of poly(3-thiopheneacetic acid) film has been rectified via network formation, as derived from electropolymerization of 3-thiopheneacetic acid with 3,3′-bithiophene or hexamethylene diisocyanate-bithiophene, without losing its conductivity and self-doping property. Solvent swelling behaviors of poly(3-thiophene acetic acid) and its network films rely on the film composition and solvent. The network film crosslinked by 3,3′-bithiophene exhibits a drastic volume change when the temperature exceeds 100°C. The passivation mechanism proposed here explains the electrical conductivity's decrease and the IR spectra's changes after iodine doping.

The surfaces of Ar plasma-pretreated polytetrafluoroethylene (PTFE) films are further functionalized via UV-induced graft copolymerization with amphoteric N,N′-dimethyl(methacryloylethyl)ammonium propansulfonate (DMAPS) either in Ar atmosphere, or under atmospheric conditions and in the absence of a polymerization initiator. The so-modified PTFE films from either process are capable of exhibiting adhesive-free adhesion or auto-adhesion with one another when brought into intimate contact in the presence of a small quantity of water. The lap shear adhesion strength increases with increasing graft concentration and can readily exceed the yield strength of the PTFE substrate. Two plasma-pretreated PTFE films also readily undergo thermal graft copolymerization with concurrent lamination when lapped together in the presence of a small quantity of the DMAPS monomer solution at elevated temperature in the atmosphere. The surface compositions of the graft-copolymerized PTFE films and the delaminated surfaces were characterized by X-ray photoelectron spectroscopy (XPS). In most cases, adhesional failure occurred near the graft-substrate interphase. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3107–3114, 1998

The compatibility and crystallization behavior of poly(phenyl acetylene) (PPA) polycaprolactone (PCL) blends were investigated. PPA and PCL were partially miscible in the melt. PCL composition in the PCL-rich phase was calculated from the observed glass transition temperature with the consideration of the perturbation of amorphous phase composition by the crystallization of PCL. PCL composition in PCL-rich phase ranged from ca. 91 wt% to 94 wt%. The melting point of PCL was depressed upon blending. The isothermal crystallization kinetics of the blends was analyzed by Avrami equation. The crystallization rate decreased with increasing PPA composition in the PCL-rich phase. The crystal fold surface free energy σ e of ca. 90 erg cm -2 was obtained from Lauritzen Hoffman analysis considering regime II kinetics. Fold surface free energy was found to increase slightly with PPA composition.

A series of new soluble polyamides having flexible ether and bulky pendant cyclododecylidene groups in the polymer chain were prepared by the direct polycondensation of 1,1-bis(4-(4-aminophenoxy)phenyl)cyclododecane (BAPCD) and various aromatic dicarboxylic acids in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. Polymers having inherent viscosities of 0.74–1.00 dl/g were produced in high yield. Almost all the polymers could be readily dissolved in polar solvents such as NMP, dimethylsulfoxide, N,N-dimethylacetamide, N, N-dimethylformamide, m-cresol, pyridine and tetrahydrofuran. Most of the polymers could be solution-cast into transparent, flexible, tough films which were further characterized by X-ray and mechanical analysis. X-ray diffractograms of polyamides indicated all polymers were amorphous except the polymer derived from rigid diacid such as 4,4′-biphenyldicarboxylic acid. Most of the polymers revealed a distinct glass transition on the differential scanning calorimetry traces in the range of 234–273 °C. Thermogravimetric analysis showed that most of the polymers were stable up to 400°C in nitrogen atmosphere. The polymer films had a tensile strength range of 88–147 MPa and high tensile modulus range of 2.8–3.5 GPa. © 1998 John Wiley & Sons, Ltd.

New poly(amide–imide)s were prepared from a diimide–dicarboxylic acid, 1,4-bis(4-trimellitimidophenoxy)-2-tert-butylbenzene (BTTB), with various diamines by the direct polycondensation in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. The new diimide–dicarboxylic acid BTTB containing an ether linkage and tert-butyl substituent was synthesized by the condensation reaction of 1,4-bis(4-aminophenoxy)-2-tert-butylbenzene with trimellitic anhydride. All the polymers were obtained in quantitative yields with inherent viscosities of 0.62–1.06 dL g−1. The polymers were amorphous, and most of them were readily soluble in aprotic polar solvents such as NMP, N,N-dimethylacetamide (DMAc), and N,N-dimethylformamide (DMF), as well as in less polar solvents such as dimethyl sulfoxide (DMSO), m-cresol, pyridine, and γ-butyrolactone, and also even in tetrahydrofuran. The glass transition temperatures of the polymers were determined by DSC method, and they were in the range of 238–279°C. These polymers were stable up to 408–449°C in air and 451–483°C in nitrogen and lose 10% weight in the range of 479–525°C in air and 480–528°C in nitrogen atmosphere. The polymer films had a tensile strength range of 71–115 MPa, an elongation at break range of 4–14%, and a tensile modulus range of 2.3–3.1 GPa. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2301–2307, 1998

In this article we will discuss the synthesis of the new copolymers of norbornene derivatives with an ester group and carbon monoxide, using Pd(CH 3 CN) 4 (BF 4 ) 2 as a catalyst and 2,2'-bipyridine as a ligand in nitromethane/methanol at 60°C. Elementary analysis, infrared spectra, and NMR spectra indicated that copolymers contain ketone, ester, and bicyclic structures. Methanol functions as the coinitiator and chain transfer agent in copolymerization. A decrease in the molar ratio of [CH 3 OH]/[Pd] caused an increase in molecular weight and a decrease in yield of the copolymer. The number-average molecular weight of copolymers (M n ) ranged from 3800 to 5300, and the glass transition temperature (T g ) ranged from -32 to 117°C. Thermal analysis revealed that both T d10% and T dmax exceeded 180 and 230°C, respectively. Linear long-chain substituents such as n-C 11 H 23 C(O)-O-CH 2 - drastically reduced T g to a value of-32°C. In general, copolymers having a longer linear side-chain substituents of ester on norbornene have a more desirable solubility. Moreover, X-ray diffraction demonstrated that the degree of crystallinity decreases with an increasing length of side chain substituents.

A diamine monomer containing isopropylidene and methyl substituted arylene ether, 2,2-bis[3,5-dimethyl-4-(4-aminophenoxy)phenyl]propane (TBAPP), was prepared in two steps. The monomer was reacted with six different aromatic tetracarboxylic dianhydrides in N.N-dimethylacetamide (DMAc) to obtain the corresponding new polyimides via the poly(amic acid) precursors and thermal or chemical imidization. The poly(amic acid)s obtained had inherent viscosities ranging from 1.38-2.10 dL . g 1 . All the poly-(amic acid)s could be cast from DMAc solutions and thermally converted into transparent, flexible, and tough polyimide films. The polyimide films had a tensile strength in the range from 52-95 MPa, an elongation at break within a range of 4-8%, and a tensile modulus in the range from 1.60-2.09 GPa. All polyimides were amorphous. The polyimides derived from diamine TBAPP had excellent solubility in various solvents except for those derived from rigid dianhydrides such as pyromellitic dianhydride and 3,3',4,4'-biphenyltetracarboxylic dianhydride. These polyimides showed glass transition temperatures between 249-293 C and decomposition temperature at 10% mass loss temperatures ranging from 460-485°C in nitrogen.

The relationship between the structure and property of polyurethane elastomer derived from bisphenol-S derivatives/diisocyanate system was studied. The effects of the amount of soft segment of diol, including ester and ether, as well as the effects of structure of diisocyanate on the mechanical properties of elastomer were discussed on the basis of the results obtained from the hardness, tensile strength, elongation, swelling, dynamic mechanical analysis, and X-ray diffraction. Also, the thermal properties of polyurethane elastomer were also investigated by d.s.c. and t.g.a. analyses. The d.s.c. and dynamic properties results demonstrated that the new polyurethanes exhibit a range of glass transition temperatures from − 25 to 48°C, and temperature at loss tan δ peak from 81.0 to 13.7°C. Moreover, t.g.a. results showed that the addition of an ester group increased the thermal stability of polyurethanes.

The aqueous solution properties of an ampholytic naphthalene-labelled acrylamide/N,N-dimethyl maleimido propyl ammonium propane sulphonate copolymer, poly(ADMMAPS)/NA, are examined in this study by measuring reduced and intrinsic viscosities. The intrinsic viscosity of the poly(ADMMAPS)/NA is related to the type and concentration of the salt added. This behaviour, resulting from the associations of the polymer chains, is in contrast with cationic and anionic polyelectrolytes. Smaller anions, such as F-, with a common cation (K+) are found to be the most difficult to be bound to the sulphonate group, indicating that a lower intrinsic viscosity of the poly(ADMMAPS)/NA would be found in aqueous KF solution. Smaller cations, such as Li+, with a common anion (Cl-) are found to be the most difficult to be bound to the quaternary ammonium group, indicating that a lower intrinsic viscosity of the poly(ADMMAPS)/NA would be found in LiCl salt aqueous solution. Because a naphthalene label was introduced into the polymer, the behaviour of the solution properties of the poly(ADMMAPS)/NA could be clearly defined in term of macroscopic and microscopic analysis. The models proposed in this study can account for the poly(ADMMAPS)/NA solution viscosities. © 1998 SCI.

The photophysical and solution properties of naphthalene-labeled styrene/N,N-dimethyl maleimido propylammonium propane sulfonate copolymer, poly(SDMPAPS)/NA, were studied in terms offluorescence, cloud point, and viscosity measurements. The ratio of intensities of the excimer and monomer fluorescence (I E /I M ) was shown as a function of polymer concentration in deionized water. The value of I E /I M decreases with an increase in the salt concentration. The addition of anionic surfactants to the aqueous solution of poly(SDMPAPS)/NA can either induce or break the interpolymer aggregation. When the electrolyte concentration increases, the Stern-Volmer quenching constant (K sv ) also increases. The phase behavior of poly(SDMPAPS)/NA shows an upper critical solution temperature around 17 °C. The intrinsic viscosity of the poly(SDMPAPS)/NA in the presence of different salts reflects the influence of these salts on the hydrodynamic volume of the polymer chain for poly(SDMPAPS)/NA. A model of the interaction between poly(SDMPAPS)/NA and surfactant in aqueous solution is proposed.

The diamine 1,4-bis(4-aminophenoxy)-2,5-di-tert-butylbenzene, containing symmetric, bulky di-tert-butyl substituents and a flexible ether unit, was synthesized and used to prepare a series of polyamides by the direct polycondensation with various aromatic dicarboxylic acids in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.32-1.27 dL g -1 . Most of these polyamides, except II a , II d , and II e , showed an amorphous nature and dissolved in polar solvents and less polar solvents. Polyamides derived from 4,4'-sulfonyldibenzoic acid, 4,4'-(hexafluoroisopropylidene)dibenzoic acid, and 5-nitroisophthalic acid were even soluble in a common organic solvent such as THF. Most polyamide films could be obtained by casting from their N,N-dimethylacetamide (DMAc) solutions. The polyamide films had a tensile strength range of 49-78 MPa, an elongation range at break of 3-5%, and a tensile modulus range of 1.57-2.01 GPa. These polyamides had glass transition temperatures ranging between 253 and 276°C, and 10% mass loss temperatures were recorded in the range 402-466°C in nitrogen atmosphere.

A series of new soluble polyamides having isopropylidene- and methyl-substituted arylene ether moieties in the polymer chain were prepared by the direct polycondensation of 3,3 ',5,5 '-tetramethyl-2,2-bis [4-(4-aminophenoxy ) phenyl ] propane (TBAPP) and various aromatic dicarboxylic acids in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. Polymers were produced with high yield and moderate to high inherent viscosities of 0.87-1.56 dL g -1 . All the polymers could be readily dissolved in polar aprotic solvents such as NMP, N,N-dimethylacetamide and N,N-dimethylformamide, as well as less polar solvents such as m-cresol and pyridine. Some of them were even soluble in tetrahydrofuran. These polymers were solution-cast into transparent, flexible, tough films which were further characterized by x-ray and mechanical analysis. All of the polymers were amorphous and the polyamide films had a tensile strength range of 51-100 MPa, an elongation at break range of 4-11%, and a tensile modulus range of 1.90-2.53 GPa. These polyamides had glass transition temperatures between 188-255°C and 10% mass loss temperatures in the range of 439-468 and 454-483°C in nitrogen and air atmosphere, respectively.

This paper proposes using liquid dioctyl phthalate (DOP) as a scrubbing agent to reduce emissions and recycle waste DOP back to the process. Gas chroma-tography (G C) was employed to determine the DOP content in the waste gas. The effects of waste gas and scrubbing agent temperatures and the waste gas flow rate o n the removal of DOP from the waste gas were investigated. Rather good DOP removal efficiency was obtained. The relationship between the height of transfer unit (Ht) of the packed scrubbing tower and operating conditions, derived on the basis of particulate transport and impaction theories, can be used to design the packed scrubbing tower.

The surfaces of ozone-pretreated polycarbonate films were subjected to further modification by thermally induced graft copolymerization with acrylic acid (AAc), sodium salt of styrene sulfonic acid (NaSS), N,N-dimethylacrylamide (DMAA), N,N-(dimethylamino)ethyl methacrylate (DMAEMA) and 3-dimethyl(methacryloyl ethyl)-ammonium propanesulfonate (DMAPS) monomers. The structure and composition at the copolymer interface were studied by angle-resolved X-ray photoelectron spectroscopy (XPS). For polycarbonate films with a substantial amount of grafted polymer, the hydrophilic graft penetrates or becomes partially submerged beneath a thin surface layer of dense substrate chains. This microstructure was further supported by the water contact angle measurements. Adhesive-free adhesion studies revealed that the AAc, DMAA or DMAPS graft copolymerized polycarbonate film surface adhered strongly to another similarly modified surface (homo-interface) when brought into direct contact in the presence of water and subsequently dried. The development of the lap shear strength is dependent on the concentration of the surface graft, the microstructure of the grafted surface, the adhesion (drying) time, and the nature of the interfacial interaction. The simultaneous presence of chain entanglement and electrostatic interaction readily results in substantially enhanced adhesion strengths between two DMAPS graft copolymerized surfaces or between an AAc and a DMAA graft copolymerized surface (hetero-interface). XPS analyses of the delaminated surfaces suggest that failure occurred cohesively below the graft-substrate interface. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 357–366, 1998

A new oxetane-containing polyether was synthesized by polycondensation of bisphenol-AF (BPAF) with 3,3-bis(chloromethyl)oxetane (BCMO) using the phase-transfer catalyzed method. The polycondensation proceeded very smoothly in aromatic solvents, catalyzed by quaternary ammonium or phosphonium salts, such as tetrabutylammonium bromide (TBAB) and tetrabutylphosphonium bromide (TBPB), to afford the polymer with high yield and molecular weight. Further, a polymer with relatively high molecular weight was obtained when the reactions were carried out in aromatic and lipophilic solvents such as benzene and nitrobenzene. The modification of this oxetane-containing polyether was easily achieved by carrying out ring-opening of the oxetane ring by using hydrogen chloride in methylene chloride, which produced a functional polymer containing hydroxyl and chloro groups. The oxetane-containing polyether was observed to be soluble in chlorinated aliphatic hydrocarbons such as methylene chloride and chloroform, as well as polar solvents such as DMSO, DMF, and DMAc, and also some common organic solvents such as benzene and toluene. However, it was insoluble in both aliphatic hydrocarbons as well as alcoholic solvents. The oxetane-containing polyether was observed to start losing weight at around 300°C under nitrogen atmosphere, and 10% weight loss was measured to be 411°C. The glass transition temperature of the oxetane-containing polyether was measured to be 134°C and the wide-angle X-ray diffraction pattern revealed this polymer to be semicrystalline. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 103–107, 1998

The synthesis, rheological, and fluorescence properties of cationic watersoluble copolymer, naphthalene-labeled cationic poly(dimethyl sulfate quaternized acrylamide/N,N-dimethylaminopropylmaleimide copolymer), poly(DSQADMAPM)/ NA, are reported. When fluorescent hydrophobes (naphthyl group) are incorporated into the cationic copolymer, the photophysical response may effectively probe solution behavior on the microscopic level. The salt and pH responsiveness inherent to the cationic copolymer systems is a function of ionic group type. Experimental results indicate that I E /I M increases steadily with increases in polymer concentration and I E / I M values for a given polymer concentration are higher in salt. At low pH values, I E / I M is high and excimer emission increases as the quaternary amino groups (R 4 N + ) are screened out. Dynamic light scattering (QELS) measurements indicate that diffusion coefficients of the cationic copolymer increase and the hydrodynamic diameters decrease with increasing salt concentration. Viscosity studies reveal that the polymer coil shrinks as salt is added. In fluorescence quenching study, the reduction in the quenching efficiency of thallium (Tl + ) with salt addition can arise from enhanced compartmentalization of naphthalene labels as added electrolyte enhances intrapolymer micellization. The intrapolymer micelle is easily formed, indicating that the thallium ion has difficulty in reacting with bound naphthalenes located in the shrunk polymer coil. The cationic copolymer is depicted as an expanded polymer coil in deionized water because of intra-and interchain repulsions. Consequently, salt addition breaks down the repulsions and enhances intrapolymer micellization.

The surfaces of low density polyethylene (LDPE), poly(carbonate) (PC), polytetrafluoroethylene (PTFE) and emeraldine (EM) base films of poly(aniline) are modified by graft copolymerization with N,N-dimethylacrylamide (DMAA), Na salt of styrenesulfonic acid (NaSS), 3-dimethyl(methacryloylethyl)ammonium propanesulfonate (DMAPS) and acrylic acid (AAc). Two surface graft copolymerized films are capable of exhibiting ‘adhesive-free’ adhesion or auto-adhesion when brought into contact in the presence of water and subsequently dried. The development of the lap shear adhesion strength depends upon the concentration of the surface graft, the contact adhesion (drying) time, the nature of the substrate, the microstructure of the graft copolymerized surfaces and the extent of molecular interaction (dispersive, electrostatic, etc.) at the lapped junction. Lap shear adhesion strengths in excess of 90 N cm−2 were readily achieved between films graft copolymerized with the amphoteric DMAPS, as well as between a DMAPS graft copolymerized EM film and an AAc graft copolymerized PTFE film. X-ray photoelectron spectroscopy (x.p.s.) analysis of the delaminated surfaces suggests that the failure mode involves the fracture of the graft chains at the substrate-graft interface.

In this work, we synthesised a new diamine containing noncoplanar 2,2′-dimethyl-biphenylene and flexible aryl ether units, 2,2′-dimethyl-4,4′-bis(4-aminophenoxy)biphenyl (DBAPB), by nucleophilic substitution of 2,2′-dimethylbiphenyl-4,4′-diol with p -chloronitrobenzene in the presence of K 2 CO 3 , followed by catalytic reduction with hydrazine/PdC system. A series of aromatic polyamides having inherent viscosities of 1.03–1.48 dl g −1 were prepared by direct polycondensation with aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. Nearly all of the polymers revealed an amorphous nature and were readily soluble in a variety of organic solvents. These polymer films had a tensile strength ranging from 22 to 65 MPa. The glass transition and melting temperature of these polyamides could be determined by d.s.c. and ranged from 226 to 273°C and 392–438°C, respectively. These polyamides remained fairly stable up to a temperature around or below 400°C. Moreover, 10% mass losses were recorded in the range 467–496°C in nitrogen atmosphere. The new polyimides were synthesised from DBAPB and various aromatic tetracarboxylic dianhydrides by the conventional two-step method which involved ring-opening polyaddition to form poly(amic acid)s and subsequently thermal or chemical cyclodehydration to polyimides. The inherent viscosities of poly(amic acid)s and polyimides were in the range 1.32–2.01 and 0.82–1.10 dl g −1 , respectively. These polyimide films had a tensile strength range of 83–139 MPa. These polyimides had glass transition temperatures between 239 and 303°C. Thermogravimetric analyses demonstrated that almost all polymers were stable up to 450°C, and the 10% mass loss temperatures were recorded in the range 488–534°C in nitrogen.

The separation of water/alcohol mixtures was carried out using a series of fluorine-containing aromatic polyamide membranes. Aromatic polyamides were prepared by direct polycondensation of fluorine-containing diamine (2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, BAPPH) and various aromatic diacids. The separation factor toward water increased when the feed ethanol concentration was increased. The solubility of ethanol in aromatic polyamide membrane is higher than that of the water, but the diffusivity of water across the membrane is higher than that of alcohols. A separation factor of 83 and a permeation rate of 262 g/m2h with a 90 wt% feed ethanol concentration at 25 °C was obtained.