Poly(ether ketone azomethane)s and poly(ether ketone imide)s containing naphthylene moieties

A new diamine monomer, 1,5-bis[4-(4-aminophenoxy)]benzoyl-2,6-dimethoxynaphthalene, was synthesized via a Friedel–Crafts acylation reaction followed by an aromatic nucleophilic substitution reaction. Six ether–ketone linked polymers, named as poly(ether ketone azomethane)s and poly(ether ketone imide)s, were successfully prepared through the polycondensations of the diamine monomer with dialdehydes and dianhydrides, respectively. These naphthylated polymers exhibited high T _g values (142–288 °C), due to their bulky and rigid chemical structure. Meanwhile, they showed good thermal stability and improved solubility. Typically, some of them were casted into thin flexible film and showed high moduli.     

Synthesis of Poly(arylene ether ketone)s containing Unsymmetrical Pyridyl Ether Linkages

Summary New high molecular weight poly(arylene ether ketone)s were prepared from pyridine containing unsymmetrical dichloro monomers. Incorporation of unsymmetrical pyridyl ether linkages instead of phenylene ether linkages reduces the high crystallinity of parent poly(arylene ether ketone)s and provides enhanced solubility. Replacement of a single atom in the repeating units of polymers can efficiently change the physical properties of the resulting polymers. The pyridyl ether containing poly(arylene ether ketone)s showed outstanding thermal stability (T_d5>470 °C).     

Synthesis and properties of novel poly(aryl ether ketone)s containing imide linkages in the main chains

A new monomer containing imide linkages, bis[4-(p-phenoxybenzoyl)-1,2-benzenedioyl]-N,N,N′,N′-4,4′-diaminodiphenyl ether (BPBDADPE), was prepared by the Friedel–Crafts reaction of bis(4-chloroformyl-1,2-benzenedioyl)-N,N,N′,N′-4,4′-diaminodiphenyl ether (BCBDADPE) with diphenyl ether (DPE). Novel poly(aryl ether ketone)s containing imide linkages in the main chains (PEK-I) were synthesized by electrophilic Friedel–Crafts solution copolycondensation of terephthaloyl chloride (TPC) with a mixture of DPE and BPBDADPE. The polymers were characterized by different physico-chemical techniques. The polymers with 10–40 mol% BPBDADPE are semicrystalline and had increased T _gs over commercially available poly(ether ether ketone) (PEEK) and poly(ether ketone ketone) (PEKK) (70/30) due to the incorporation of imide linkages in the main chains. The polymers IV and V with 30–40 mol% BPBDADPE had not only high T _gs of 182–183 °C, but also moderate T _ms of 341–343 °C, having good potential for melt processing and exhibited high thermal stability and good resistance to common organic solvents.     

Novel high performance poly(aryl ether ketone)s based on symmetrical naphthylene isomers

Summary  Two new bisphenol monomers containing naphthylene groups were synthesized by a Friedel-Crafts acylation reaction followed by a demethylation reaction. Four naphthylated poly(aryl ether ketone)s (PANEKs) were successfully prepared via a typical nucleophilic substitution polycondensation. These PANEKs exhibited excellent properties including high T_gs (above 204^oC) and good thermal stability (the temperature at 5% weight loss in air was above 430^oC). They had improved solubility, and flexible and transparent membranes could be cast from their solutions. The good mechanical property (tensile strength of 82.2∼102.8 MPa, Young’s moduli of 2.1∼2.4 GPa, and elongation at break of 17∼31%) indicated they were strong materials. Low dielectric constant (2.8-2.9 at 1 MHz) and moisture absorptions (i<<0.45%) were also detected from the polymer films.     

Preparation of a new type of ion‐exchange membrane based on sulfonated poly(ether ether ketone ketone)s

Novel sulfonated poly(ether ether ketone ketone)s were prepared directly by nucleophilic polycondensation. They showed excellent thermal stability and good solubility and could be easily cast into tough membranes. The sulfonated membranes showed swelling of 16.08–26.71% and an ion‐exchange capacity of 1.01–1.57. The transport properties of different cations (H⁺, Na⁺, and K⁺) of membranes based on these polymers were evaluated. The potential for ion‐exchange membranes looks good. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2481–2486, 2005     

Synthesis, characterization, thermal degradation, and comparative chain dynamics studies of weak-link polysulfide polymers

Synthesis, spectroscopic and thermal characterization of two new classes of polysulfide polymers: poly[1-(phenoxymethyl) ethylene polysulfide] (PPMEP), and poly[1-(phenoxy) ethylene polysulfide] (PPEP) is presented. The direct pyrolysis mass spectrometry (DP-MS) technique, used to study the thermal degradation behavior of these polysulfide polymers, indicated that the polymers underwent degradation through the weak-links scission. The thermal stability of the polysulfide polymers decreased as the “rank” (number of sulfur atoms in the polysulfide linkage; n = 1, 2, 4) increased. The main-chain flexibility of these polysulfide polymers in terms of their ¹³C NMR spin-lattice relaxation time (T ₁ ) measurements on the backbone methine (-CH-) and methylene (-CH₂-) carbons are reported here for the first time. A comparative study of the solution chain dynamics indicated that it increased as “rank” of the polysulfide linkages decreased as well as by introducing side chain spacers such as, ether (-O-) or methyleneoxy (-CH₂O-) groups.     

Synthesis and properties of novel phosphorus‐containing poly(ether ether ketone ketone)s

A novel monomer, bis[4‐(4‐fluorobenzoyl)phenyl]phenylphosphine oxide, was synthesized through the reaction of bis(4‐chloroformylphenyl) phenyl phosphine oxide with fluorobenzene. Three poly(ether ether ketone ketone)s derived from bis[4‐(4‐fluorobenzoyl)phenyl]phenylphosphine oxide and different aromatic bisphenols were prepared by aromatic nucleophilic substitution reactions. The resulting polymers had inherent viscosities in the range of 0.55–0.73 dL/g. The structures of the poly(ether ether ketone ketone)s were characterized with Fourier transform infrared and ¹H‐NMR. Thermal analysis indicated that the glass‐transition temperatures of the poly(ether ether ketone ketone)s were higher than 200°C, and the 5% weight loss temperatures in nitrogen were higher than 463°C. All the polymers showed excellent solubility in polar solvents such as N‐methyl‐2‐pyrrolidone, dimethylformamide, and dimethylacetamide and could also be dissolved in chlorinated methane. The polymers afforded transparent and flexible films by solvent casting. Organic phosphorous moieties also imparted good flame‐retardancy to the polymers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Synthesis and properties of poly(aryl ether ketone)s containing both biphenylene moieties and sulfone linkages in the main chain

Two monomers, 4,4′‐bis(4‐phenoxybenzoyl)biphenyl (BPOBBP) and 4,4′‐diphenoxydiphenyl sulfone (DPODPS), were conveniently synthesized via simple synthetic procedures from readily available materials. A series of novel poly(aryl ether ketone)s containing both biphenylene moieties and sulfone linkages in the main chain were synthesized by the modified electrophilic Friedel‐Crafts acylation copolycondensation of isophthaloyl chloride (IPC) with a mixture of BPOBBP and DPODPS, over a wide range of BPOBBP/DPODPS molar ratios. The resulting polymers were characterized by Fourier transform infrared spectroscopy (FT‐IR), wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA), etc. The results indicated that the copolymers with 30 to 35 mol% DPODPS were semicrystalline and had remarkably increased glass transition temperatures (T_gs) over the conventional poly(ether ether ketone) (PEEK) and poly(ether ketone ketone) (PEKK) due to the incorporation of biphenylene units and sulfone linkages in the main chain. The copolymers with 30 to 35 mol% DPODPS had not only high T_gs of 176 to 177°C, but also moderate melting temperatures (T_ms) of 334 to 337°C, having good potential for the melt processing. The semicrystalline copolymers II to V had tensile strengths of 99.8 to 103.1 MPa, Young's moduli of 2.26 to 2.79 GPa, and elongations at break of 16.8 to 26.5% and exhibited outstanding thermal stability and good resistance to organic solvents. POLYM. ENG. SCI., 55:2140–2147, 2015. © 2015 Society of Plastics Engineers     

Synthesis and characterization of poly(ether ketone ketone) (PEKK)/sodium sulfonated poly(arylene ether ketone) (S‐PAEK) block copolymers

A series of well‐defined poly(ether ketone ketone) (PEKK)/sodium sulfonated poly(aryl ether ketone) (S‐PAEK) block copolymers of high molecular weights was prepared by direct nucleophilic polymerization of hydroquinone with sodium 5,5′‐carbonylbis(2‐fluorobenzene sulfonate) ( 1 ) and PEKK oligomer ( 2 ). Varying the ratio of 1 to 2 used in polymerization can be used to control the degree of polymer sulfonation, which correspondingly affects the polymer solubility in solvents. Increasing content of 1 in the copolymers, slightly decreases their thermal stability which is nevertheless thermally stable up to 400 °C. Two T_g values, or one broad T_g, were observed in the DSC measurements of the block copolymers, indicating the existence of phase separation, which was further proved by phase‐separated morphologies as shown in atomic force microscopy images. © 2001 Society of Chemical Industry     

Synthesis and characterization of poly(aryl ether ketone) oligomers terminated with metallophthalocyanine to be used for oxidative decomposition of TCP

A series of metallophthalocyanine‐terminated poly(aryl ether ketone) oligomers were synthesized from dicyanobenzene‐terminated poly(aryl ether ketone) oligomers with different metal chloride and phthalonitrile. All polymers exhibited high glass transition temperature and good thermal stability. These polymers showed optical absorption in the visible region and had different colors in chloroform solution. Cobalt phthalocyanine‐terminated poly(aryl ether ketone) oligomers exhibited good catalytic activity in oxidative decomposition of 2,4,6‐trichlorophenol (TCP) under H₂O₂ and KHSO₅. The catalytic activity of KHSO₅ is much better than H₂O₂, and more than 70% of initial TCP was decomposed within 7 h. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Soluble,semi-crystalline PEEK analogs based on 3,5-difluorobenzophenone: Synthesis and characterization

The solubility and thermal properties of poly(ether ether ketone) (PEEK) have been modified by utilizing various ratios of the traditional electrophilic component, 4,4′-difluorobenzophenone, 1, utilized to synthesize PEEK and a comonomer, 3,5-difluorobenzophenone, 2, which is simply a geometric isomer of 1. The resulting polymers (“m-PEEK”) have the same chemical composition as PEEK, allowing for accurate structure–property relationships to be determined. The thermal properties were investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The ratio of monomer 1 to monomer 2 had a dramatic influence on the thermal properties and solubility characteristics of PEEK. At higher ratios, 90:10, 85:15, and 80:20, the materials were semi-crystalline and their solubility was very limited in solvents such as N-methyl-pyrrolidinone (NMP) while at lower ratios, 75:25 and 50:50, the PEEK derivatives were completely amorphous and soluble in NMP. TGA analysis indicated excellent thermal stability as most of the materials displayed 5% weight loss temperatures (T_d-5%) greater than 450 °C.     

Poly(arylene ether nitrile) copolymers containing pendant phenyl: Synthesis and properties

A series of poly(arylene ether nitrile) copolymers (PENAPs) were synthesized with bisphenol A (BP-A), bisphenol AP (BP-AP) and 2,6-Dichlorobenzonitrile (DCBN) via a nucleophilic substitution polycondensation reaction. FTIR and ¹H-NMR were used to confirm the structure of PENAPs. Glass transition temperature (T_g) of PENAPs determined by differential scanning calorimetry (DSC) ranged from 154.2 to 200.8°C. The 5% weight lost temperature (T_5%) of PENAPs were 418.9–447.7°C. The tensile and DMA test indicated that PENAPs possessed excellent mechanical properties with tensile strength more than 92.8 MPa and storage modulus more than 1.0 GPa at about 150°C. The melt flowability was measured by rheology properties testing ranging from 80 to 1639 GPa at 290°C and under shear frequency 100 Hz, which indicated the copolymers had good flowability and thermal stability. Additionally, PENAPs could be dissolved in many solutions, which meant PENAPs had good solubility and can be processed by solution method.     

Thermal stability,solubility, and fluorescence property of poly(arylene ether ketone)s bearing <Emphasis Type="Italic">N</Emphasis>-arylenebenzimidazole units

A series of novel random poly(arylene ether ketone)s containing N-arylenebenzimidazolyl groups with precise structures in high yields were synthesized from 2-(2′-hydroxyphenyl) benzimidazole and 4,4′-dihydroxybenzophenone with 4,4′-difluorobenzophenone via nucleophilic substitution polycondensation reaction using sulfolane as a solvent. The reaction was carried out at 210 °C in the presence of anhydrous potassium carbonate. The structures of the resulted polymers were characterized by means of FT-IR, ¹H NMR spectroscopy, and elemental analysis, and the results were largely consistent with the proposed structure. X-ray diffraction studies revealed that the incorporation of N-arylenebenzimidazolyl groups decreased the crystallinity of the resulted polymers. As the benzimidazole unit content in the copolymer increased, the solubility and thermal behavior of the prepared polymers improved. The novel poly(arylene ether ketone)s exhibited glass transition temperatures (T _gs) in the range 188–237°C, and there was a good linearity relationship between T _g values and the content of benzimidazolyl groups. The 5% decomposition temperatures were within the range of 512–539 °C in nitrogen and 496–540 °C in air indicating their good thermal stability. Tensile tests of the films showed that these polymers have desirable mechanical properties. Moreover, the resulting polymers showed good fluorescence properties.     

Poly(aryl imino sulfone)s as new high-performance engineering plastics

Abstract  

Poly(aryl imino sulfone)s (PAISs) as novel high-performance polymers have been obtained by the condensation polymerization of 4,4′-dibromodiphenyl sulfone with different primary aromatic diamines via Palladium-catalyzed aryl amination reaction. The influence of the halogen-containing monomers, solvent, concentration, and temperature on the polycondensation reaction was investigated. The structure of polymers synthesized was characterized by means of FT–IR, NMR spectroscopy, and elemental analysis, the results showed an agreement with the proposed structure. Differential scanning calorimetry and thermal analysis measurements showed that polymers possessed high glass transition temperature (T _g > 145 °C) and good thermal stability with high decomposition temperatures (T _D > 450 °C). These novel polymers also exhibited good mechanical behaviors and good solubility.     

Probing effects of alternately‐embedded phenoxy phenyl lateral groups on properties of novel aromatic poly(ether‐urea)s

A new class of alternate aromatic poly(ether‐urea)s having bulky phenoxy phenyl lateral groups was prepared by the reaction of 2,2′‐bis[(p‐phenoxy phenyl)]‐4,4′‐diaminodiphenyl ether (PPAPE) with two diisocyanates, isophorone diisocyanate and 2,4‐tolylene diisocyanate. The limited viscosity values as well as M _n and M _w values of the resulting polymers were determined. The resulting poly(ether‐urea)s could be easily cast into optically‐transparent, flexible, and light color films. The cut‐off wavelength values and the percentage of transmittance at 800 nm were found to be at about 415 nm and 85%, respectively. PPAPE‐derived poly(ether‐urea)s showed a low‐crystallinity and had excellent solubility in polar organic solvents. T_onset, T_g, T_d5%, and T_d10% values of the PPAPE‐derived polymers measured from their DSC and TGA thermograms were up to 270, 280, 315, and 340°C, respectively. Surface morphology of the resulted poly(ether‐urea)s were also evaluated by their scanning electron microscopy images. Excellent organo‐solubility, satisfactory film quality, moderate T_g values, and good thermal stability make this class of poly (ether‐urea)s promising high‐performance polymeric materials. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Preparation and properties of film materials of poly(aryl ether ketone)–based phthalonitrile resins

A series of poly(aryl ether ketone) polymers (m‐PAEK‐CN) containing phthalonitrile were synthesized by a direct solution polycondensation and characterized by Fourier‐transform infrared spectroscopy and hydrogen nuclear magnetic resonance. Thermal crosslinking of m‐PAEK‐CN, catalyzed by p‐BAPS, was then performed via heating their films up to 350^oC. Dynamic rheology results showed that the rate of diamine‐catalyzed crosslink reaction could be easily controlled by varying the content of cyano groups in the polymer. The uncured synthesized polymers had good solubility, whereas the cured ones became insoluble in common organic solvents. Spectra measurement demonstrated the trimerization reaction of terminal cyano groups to form triazine rings. The resulting cured samples had higher glass transition temperatures, better thermal, and thermo‐oxidative stability with high char yield than the uncured ones. Gel content measurements demonstrated that the cured polymers had high crosslinking density with significantly high gel content over 96.0%. Thermal mechanical analysis indicated that the cured phthalonitrile resins possessed excellent thermal mechanical properties and dimensional stability at increased temperatures. The tensile modulus and strength of the cured m‐PAEK‐CN increased up to 2101–2104 MPa and 96–100 MPa, respectively, which were about 21–23% and 32–56% higher than the uncured ones’. This kind of phthalonitrile resins may be used as a candidate for high‐performance polymeric film materials. POLYM. ENG. SCI., 55:2313–2321, 2015. © 2015 Society of Plastics Engineers     

Synthesis and characterization of poly(ether ketone ether ketone ketone)/poly(ether ether ketone ketone) copolymers containing naphthalene and pendant cyano groups

2,6‐Bis(β‐naphthoxy)benzonitrile (BNOBN) was synthesized by reaction of β‐naphthol with 2,6‐difluorobenzonitrile in N‐methyl‐2‐pyrrolidone (NMP) in the presence of KOH and K₂CO₃. Poly(ether ketone ether ketone ketone)(PEKEKK) /poly(ether ether ketone ketone) (PEEKK) copolymers containing naphthalene and pendant cyano groups were obtained by electrophilic Friedel‐Crafts polycondensation of terephthaloyl chloride (TPC) with varying mole proportions of 4,4′‐diphenoxybenzophenone (DPOBP) and 2,6‐bis(β‐naphthoxy)benzonitrile (BNOBN) using 1,2‐dichloroethane (DCE) as solvent and NMP as Lewis base in the presence of anhydrous AlCl₃. The resulting polymers were characterized by various analytical techniques, such as FTIR, DSC, TG, and WAXD. The results indicated that the crystallinity and melting temperature of the polymers decreased with increase in concentration of the BNOBN units in the polymer, the glass transition temperature of the polymers increased with increase in concentration of the BNOBN units in the polymer. Thermogravimetric studies showed that all the polymers were stable up to 536°C in N₂ atmosphere. The copolymers have good resistance to acidity, alkali, and organic solvents. Because of the melting temperature (T_m) depression with increase in the BNOBN content in the reaction system, the processability of the resultant coplymers could be effectively improved. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis and characterization of soluble aromatic poly(ether amide amide ether ketone ketone)s by electrophilic Friedel–Crafts solution polycondensation

A new monomer, N,N′-bis(4-phenoxybenzoyl)-m-phenylenediamine (BPBMPD), was prepared by condensation of m-phenylenediamine with 4-phenoxybenzoyl chloride in N,N-dimethylacetamide (DMAc). Novel soluble aromatic poly(ether amide amide ether ketone ketone)s (PEAAEKKs) were synthesized by electrophilic Friedel–Crafts solution copolycondensation of BPBMPD with a mixture of terephthaloyl chloride (TPC) and isophthaloyl chloride (IPC) in the presence of anhydrous aluminum chloride and N-methylpyrrolidone (NMP) in 1,2-dichloroethane (DCE). The influences of reaction conditions on the preparation of polymers were examined. The polymers obtained were characterized by different physico-chemical techniques such as FT-IR, DSC, TGA, and wide-angle X-ray diffraction (WAXD). All the polymers were amorphous and the solubility of the polymers was improved by the incorporation of 1,3-dibenzoylaminobenzene moieties in the main chain. Thermal analyses showed that the polymers had high T_gs of 220–231 °C and exhibited high thermal stability. All the polymers formed transparent, strong, and flexible films, with tensile strengths of 102.9–108.5 MPa, Young’s moduli of 2.44–2.86 GPa, and elongations at break of 9.8–13.7%.     

Synthesis and characterization of soluble polyamides from bis-[(4′-aminobenzyl)-4-benzamide] ether and various diacids

New aromatic diamine containing preformed amide, ether, and methylene; bis-[(4′-aminobenzyl)-4-benzamide] ether (BABE), was synthesized and characterized by FT-IR, NMR, and mass spectrometry. Aromatic–aliphatic polyamides were prepared from BABE with aliphatic/aromatic diacids via Yamazaki’s polymerization. The polyamides were characterized by FT-IR, ¹H NMR, inherent viscosity [η_inh], solubility tests, differential scanning calorimetry [DSC], thermogravimetric analysis [TGA], and X-ray diffraction [XRD]. Polyamides had inherent viscosities 0.35–0.84 dL/g, soluble in aprotic polar solvents like N-methyl-2-pyrrolidone, N, N-dimethyl acetamide and dimethyl sulphoxide containing LiCl due to an amorphous to partially crystalline morphology; as XRD patterns indicated. DSC analysis of polyamides showed glass transition temperatures 166–268 °C. Polyamides showed high thermal stability as they did not degrade below 300 °C, had 10% weight loss temperature higher than 375 °C, and the char yields at 900 °C were 22–55%; indicating potential applications as engineering materials.     

Synthesis and characterization of soluble poly(ether imide)s based on 2,2′-bis(4-aminophenoxy)-9,9′-spirobifluorene

A series of aromatic poly(ether imide)s containing 9,9′-spirobifluorene moieties in the main chain have been synthesized via the polycondensation of 2,2′-bis(4-aminophenoxy)-9,9′-spirobifluorene with a variety of aromatic dianhydrides. In the diamine monomer, the two aminophenoxyfluorene entities are orthogonally arranged and are connected through an sp³ carbon atom (the spiro center). The resulting poly(ether imide)s have a polymer backbone which is periodically twisted with an angle of 90° at each spiro center. This structural feature, which restricts the close packing of the polymer chains and reduces inter-chain interactions, leads to amorphous poly(ether imide)s with good solubility in common organic solvents. In addition, the rigidity of the main chain of these polymers appears to be preserved due to the spiro-structure. As a result, these poly(ether imide)s exhibit a high T_g and excellent thermal stability.