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1.
Two series of novel fluorinated aromatic polyamides were prepared from 2,2-bis(4-amino-2-trifluoromethylphenoxy)biphenyl (2) and 2,2-bis(4-amino-2-trifluoromethylphenoxy)-1,1-binaphthyl (4) with various aromatic dicarboxylic acids using the phosphorylation polycondensation technique. The polyamides had inherent viscosities ranging from 0.43 to 0.62 dl/g and 0.36 to 0.74 dl/g, respectively. All the fluorinated polyamides were soluble in many polar organic solvents such as N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidinone, and afforded transparent, light-colored, and flexible films upon casting from DMAc solvent. These polyamides showed glass-transition temperatures in the ranges of 190-240 °C (for the 6 series from diamine 2) and 247-255 °C (for the 7 series from diamine 4) by differential scanning calorimetry, softening temperatures in the ranges of 196-230 °C (6 series) and 241-291 °C (7 series) by thermomechanical analysis, and decomposition temperatures for 10% weight loss above 420 °C in both nitrogen and air atmospheres.  相似文献   

2.
A new trifluoromethylated bis(ether amine), 1,5-bis(4-amino-2-trifluoromethylphenoxy)naphthalene, was synthesized in two steps starting from 1,5-dihydroxynaphthalene and 2-chloro-5-nitrobenzotrifluoride via nucleophilic aromatic substitution and catalytic reduction. A series of novel fluorinated polyimides with moderate to high molecular weights were synthesized from the diamine with various aromatic tetracarboxylic dianhydrides using a conventional two-stage process. All polyimides could afford flexible and tough films and most of them were soluble in strong polar solvents such as N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc). The polyimides showed glass-transition temperatures (Tg) in the range of 253-315 °C (by DSC) and softening temperatures (Ts) in the range of 250-300 °C (by TMA). Decomposition temperatures for 5% weight loss all occurred above 500 °C in both air and nitrogen atmospheres. The dielectric constants of these polymers ranged from 3.17 to 3.64 at 1 MHz. The properties of these fluorinated polyimides were also compared with those of polyimides prepared from 1,5-bis(4-aminophenoxy)naphthalene with the same dianhydrides.  相似文献   

3.
Various unsaturated polyamides and polyesters were prepared from the reactions of 1,4-bis(2-carboxyvinyl)benzene acid chloride with aromatic diamines and bisphenols, respectively. In addition, various unsaturated homo- and copolyesters were synthesized from 4-hydroxycinnamic acid and 4-hydroxybenzoic acid. They were heat-cured to thermally stable resins. The polymers were characterized by inherent viscosity measurements, FT-IR, x-ray, DTA, TMA, TGA, and isothermal gravimetric analysis. The water absorption as well as the solubility behavior of the polymers was also investigated. © 1996 John Wiley & Sons, Inc.  相似文献   

4.
A series of organo-soluble polyimides were prepared from a novel fluorinated diamine monomer, 4-phenyl-2,6-bis[4-(4′-amino-2′-trifluoromethylphenoxy)phenyl]pyridine and various commercial aromatic dianhydrides. These polyimides had good solubility in common organic solvents. The obtained strong and flexible PI films exhibited excellent thermal stability with the decomposition temperature (at 5% weight loss) of above 561 °C and the glass transition temperature in the range of 258-312 °C. Moreover, the polymer films showed good electrical insulating property, low dielectric constant and low water uptake due to the introduction of fluorinated substitutes in the polymer backbone. The remarkable combined features ensure these polymers to be ideal candidate materials for advanced microelectronic industry and other related applications.  相似文献   

5.
A new structurally asymmetric diamine monomer containing flexible ether linkages and bulky trifluoromethyl substituents, namely 1,3-bis(4-amino-2-trifluoromethylphenoxy)naphthalene, was prepared from 1,3-dihydroxynaphthalene and 2-chloro-5-nitrobenzotrifluoride. New series of fluorinated polyimides were synthesized from the diamine with six commercially available aromatic tetracarboxylic dianhydrides using a conventional two-stage process with thermal or chemical imidization. The resulting polyimides were highly soluble in a variety of organic solvents and could afford transparent and tough films via solution casting. These polyimides exhibited moderately high glass-transition temperatures (by DSC) of 236-268 °C and softening temperatures (by thermomechanical analysis) of 231-250 °C, and they did not show significant decomposition before 500 °C under either nitrogen or air atmosphere. Also, they revealed low moisture absorptions (0.32-0.78%), low dielectric constants (2.81-3.24 at 10 kHz), and high optical transparency (ultraviolet-visible absorption cutoff wavelengths of 377-426 nm).  相似文献   

6.
A novel thermally stable unsaturated poly(ester-imide) (UPEI-50) was prepared by thermal polycondensation of a diimidodicarboxylic acid monomer, 1,4-bis[2′-trifluoromethyl-4′-(4″-carboxylic acid)trimellitimido phenoxy]benzene (BTTB), maleic anhydride and 1,2-propylene glycol. The poly(ester-imide) resin obtained was found to be easily dissolved in glycidyl methacrylate (GMA) to give a homogeneous resin composition with low viscosity, which was then thermally cured into thermosetting poly(ester-imide)/glycidyl polymethacrylate polymer composite (UPEI-50/GMA). Effects of curing processing parameters such as the curing temperature and curing time, the reactive monomer concentration and the initiator amount etc. on curing reaction were systematically investigated. Experimental results indicated that the thermally cured UPEI-50/GMA polymer composite exhibited outstanding thermal stability, mechanical and electrical insulating properties.  相似文献   

7.
A new aromatic ether diamine, bis[3-(4-amino-2-trifluoromethylphenoxy) phenyl] ether, was successfully synthesized via nucleophilic substitution reaction of 3,3′-oxydiphenol and 2-chloro-5-nitrotrifluoromethylbenzene, followed by a catalytic reduction. A series of new polyimides were synthesized from the diamine with various commercially available aromatic dianhydrides via a conventional two-stage process, i.e. ring-opening polyaddition forming the poly(amic acid)s and further thermal or chemical imidization forming polyimides. The resulting polyimides exhibited good solubility in polar solvents, such as N,N-dimethylacetamide, N,N-dimethylformamide, N-methyl-2-pyrrolidinone and common solvents such as chloroform, tetrahydrofuran upon heating and possessed the inherent viscosities of 0.51-0.68 dL/g. The resulting strong and flexible films exhibited excellent thermal stability with the temperature at 10% weight loss is above 502 °C and the glass transition temperature in the range of 191-232 °C. The polyimides also were found to possess high optical transparency.  相似文献   

8.
A novel fluorinated aromatic diamine 1,1′-bis(4-aminophenyl)-1-(3-trifluoromethylphenyl)-2,2,2-trifluoroethane (6FDAM) was synthesized in a simple procedure, which was then employed to prepare a series of fluorinated polyimides with commercial aromatic dianhydrides, such as pyromellitic dianhydride (PMDA), 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane (6FDA), 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) and 4,4′-oxydiphthalic anhydride (ODPA). The polyimides exhibited good solubility in strong dipolar solvents such as NMP, DMAc, DMF and m-cresol as well as some of low boiling point organic solvents of THF and CHCl3, etc. Experimental results indicated the polyimides possessed low moisture adsorptions of 0.42-0.95%, low dielectric constant of 2.71-2.95 at 1 MHz, high dielectric strength of 92.0-122.6 kV/mm and good optical transparency with cutoff wavelengths of UV-vis at 330-375 nm. The polyimides also exhibited good mechanical properties as well as excellent thermal and thermo-oxidative stability. The fluorinated polyimides possessed better solubility, lower dielectric constant and water adsorption as well as higher optical transparency than the representative non-fluorinated polyimide derived from PMDA and 4,4′-oxydianiline (ODA).  相似文献   

9.
A new tetraimide-dicarboxylic acid (TIDA) I was synthesized starting from 3-aminobenzoic acid (m-ABA), 4,4′-oxydiphthalic anhydride (ODPA), and 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene (BAFPB) at a 2:2:1 molar ratio in N-methyl-2-pyrrolidone (NMP). A series of organosoluble, light-colored poly(amide-imide-imide)s (PAII, IIIa-j) was prepared by triphenyl phosphite-activated polycondensation from the tetraimide-diacid I with various aromatic diamines (IIa-j). All the polymers were readily soluble in a variety of organic solvents such as NMP, N,N-dimethyl acetamide (DMAc), dimethyl sulfoxide, and even in less polar m-cresol and pyridine. Polymer films cast from DMAc had the cutoff wavelengths between 374 and 384 nm and had the b values in the range of 14.8-30.2. Polymers IIIa-j afforded tough, transparent, and flexible films, which had tensile strengths ranging from 87 to 103 MPa, elongations at break from 11% to 37%, and initial moduli from 1.9 to 2.3 GPa. The glass transition temperatures of these polymers were in the range of 242-274 °C. They had 10% weight loss temperature above 526 °C and showed the char yield more than 55% residue at 800 °C in nitrogen.  相似文献   

10.
New fluorinated aromatic polyimides were prepared from 1,4‐(4′‐aminophenoxy)‐2‐(3′‐trifluoromethylphenyl)benzene and aromatic dianhydrides via the polycondensation of one‐step high‐temperature and two‐step thermal or chemical imidization methods. Experimental results indicated that some of the polyimides were soluble both in strong dipolar solvents (N‐methyl‐2‐pyrrolidone or N,N‐dimethylacetamide) and in common organic solvents such as tetrahydrofuran, CHCl3, and acetone. The polyimides showed exceptional thermal and thermooxidative stability and good mechanical properties. No weight loss was detected before a temperature of 520 °C in nitrogen, and the glass‐transition temperatures ranged from 208 to 251 °C. Low dielectric constants (2.55–2.71 at 1 MHz), low refractive indices, and low water absorption were also observed. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2404–2413, 2001  相似文献   

11.
One of fluorinated polyimides was synthesized from 2,2′-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and 3,3′-dimethyl-4,4′-diaminodiphenylmethane (DMMDA) by two-steps method, which had good solubility and hydrophilicity. 6FDA-DMMDA polyimide was dissolved in chloroform (CHCl3) and cast on a glass substrate in a humid atmosphere. It was found that 6FDA-DMMDA/CHCl3 solution was easy to form ordered porous structure at high concentration, and the reason was discussed in detail. In addition, the influences of solution concentration, the atmosphere humidity, were also tested.  相似文献   

12.
A new aromatic diamine, 4-(4-trifluoromethyl)phenyl-2,6-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]pyridine, was synthesized by a modified Chichibabin reaction of 4-(4-nitro-2-trifluoromethylphenoxy)acetophenone with 4-triflouromethylbenzaldehyde, followed by catalytic reduction. A series of fluorinated pyridine-containing aromatic poly(ether imide)s (PEIs) were prepared from the diamine monomer with various aromatic dianhydrides via conventional two-step thermal imidization method. The resulting PEIs had inherent viscosities values of 0.68–0.90 dL/g, and could be cast and thermally converted into transparent, flexible, and tough polymer films. These PEIs were predominantly amorphous, had good solubility in common solvents such as NMP, DMAc and m-cresol at room temperature, and displayed excellent thermal stability with the glass transition temperatures of 258–315?°C, the temperatures at 5% weight loss of 550–585?°C, and the residue of higher than 55% at 750?°C in nitrogen. Moreover, the PEIs films showed outstanding mechanical properties with tensile strengths of 74.8–103.5?MPa, tensile moduli of 1.08–1.45?GPa, and elongations at break of 10.6–24.4%. These PEIs also exhibited low dielectric constants of 2.81–2.98 (1?MHz) and water uptake 0.39–0.68%, as well as high optical transparency with the UV cutoff wavelength in the 350–378?nm range and the wavelength of 80% transparency in the range of 412–510?nm.  相似文献   

13.
14.
A new kind of pyridine-containing aromatic diamine monomer, 4-phenyl-2,6-bis[3-(4′-amino-2′-trifluoromethyl-phenoxy) phenyl] pyridine (m-PAFP), was successfully synthesized by a modified Chichibabin reaction of 3-(4′-nitro-2′-trifluoro-methyl-phenoxy)-acetophenone with benzaldehyde, followed by a catalytic reduction. A series of fluorinated pyridine-bridged aromatic poly(ether-imide)s were prepared from the resulting diamine monomer with various aromatic dianhydrides via a conventional two-step thermal or chemical imidization method. The inherent viscosities values of these polyimides were in the range of 0.56-1.02 dL/g, and they could be cast and thermally converted into transparent, flexible, and tough polyimide films. The polyimides displayed higher solubility in polar solvents such as NMP, DMSO and m-cresol. The polyimides had good thermal stability, with the glass transition temperatures (Tg) of 187-211 °C, the temperatures at 5% weight loss of 511-532 °C, and the residue at 800 °C in air was higher than 50%. These films also had dielectric constants of 2.64-2.74 at 10 MHz and low water uptake 0.53-0.66%. Wide-angle X-ray diffraction measurements revealed that these polyimides were predominantly amorphous. Moreover, the polymer films of these novel polyimides showed outstanding mechanical properties with the tensile strengths of 90.1-96.6 MPa, elongations at breakage of 8.9-10.7% and tensile modulus of 1.65-1.98 GPa.  相似文献   

15.
The reactions of manganese(II) acetate or perchlorate, sodium azide or sodium cyanate, and the zwitterionic dicarboxylate ligand 1,4-bis(4-carboxylatopyridinium-1-methylene)benzene (L) under different conditions yielded three different Mn(II) coordination polymers with mixed carboxylate and azide (or cyanate) bridges: {[Mn (L(1))(0.5)(N(3))(OAc)]·3H(2)O}(n) (1), {[Mn(4)(L(1))(N(3))(8)(H(2)O)(4)(CH(3)OH)(2)]·[L(1)]}(n) (2), and {[Mn(3)(L(1))(NCO)(6)(H(2)O)(4)]·[L(1)]·[H(2)O](2)}(n) (3). The compounds exhibit diverse structures and magnetic properties. In 1, the 1D uniform anionic [Mn(N(3))(COO)(2)](n) chains with the (μ-EO-N(3))(μ-COO)(2) triple bridges (EO = end-on) are interlinked by the dipyridinium L ligands into highly undulated 2D layers. Magnetic studies on 1 reveal that the mixed triple bridges induce antiferromagnetic coupling between Mn(II) ions. Compounds 2 and 3 consist of 1D neutral polymeric chains and co-crystallized zwitterions, and the chains are formed by the L ligands interlinking linear polynuclear units. The polynuclear unit in 2 is tetranuclear with (μ-EO-N(3))(2) as central bridges and (μ-EO-N(3))(2)(μ-COO) as peripheral bridges, while that in 3 is trinuclear with (μ-NCO)(2)(μ-COO) bridges. Magnetic studies demonstrate that the magnetic coupling through the mixed azide/isocyanate and carboxylate bridges in 2 and 3 is antiferromagnetic. An expression of magnetic susceptibility based on a 2-J model for linear tetranuclear systems of classical spins has been deduced and applied to 2.  相似文献   

16.
A series of fluorinated poly(amide imide)s were prepared from 1,4‐bis(2′‐trifluoromethyl‐4′‐trimellitimidophenoxy)benzene and various aromatic diamines [3,3′,5,5′‐tetramethyl‐4,4′‐diaminediphenylmethane, α,α‐bis(4‐amino‐3,5‐dimethyl phenyl)‐3′‐trifluoromethylphenylmethane, 1,4‐bis(4′‐amino‐2′‐trifluoromethylphenoxy)benzene, 4‐(3′‐trifluoromethylphenyl)‐2,6‐bis(3′‐aminophenyl)pyridine, and 1,1‐bis(4′‐aminophenyl)‐1‐(3′‐trifluoromethylphenyl)‐2,2,2‐trifluoroethane]. The fluorinated poly(amide imide)s, prepared by a one‐step polycondensation procedure, had good solubility both in strong aprotic solvents, such as N‐methyl‐2‐pyrrolidinone, dimethylacetamide, dimethylformamide, dimethyl sulfoxide, and cyclopentanone, and in common organic solvents, such as tetrahydrofuran and m‐cresol. Strong and flexible polymer films with tensile strengths of 84–99 MPa and ultimate elongation values of 6–9% were prepared by the casting of polymer solutions onto glass substrates, followed by thermal baking. The poly(amide imide) films exhibited high thermal stability, with glass‐transition temperatures of 257–266 °C and initial thermal decomposition temperatures of greater than 540 °C. The polymer films also had good dielectric properties, with dielectric constants of 3.26–3.52 and dissipation factors of 3.0–7.7 × 10?3, and acceptable electrical insulating properties. The balance of excellent solubility and thermal stability associated with good mechanical and electrical properties made the poly(amide imide)s potential candidates for practical applications in the microelectronics industry and other related fields. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1831–1840, 2003  相似文献   

17.
A new aromatic unsymmetrical diamine monomer, 1,4-(2′,4″-diaminodiphenoxy)benzene (OAPB), was successfully synthesized in three steps using hydroquinone as starting material and polymerized with various aromatic tetracarboxylic acid dianhydrides, including 4,4′-oxydiphthalic anhydride (ODPA), 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BTDA), 2,2′-bis(3,4-dicarboxyphenyl)-hexafluoropropane dianhydride (6FDA) and pyromellitic dianhydride (PMDA) via the conventional two-step thermal or chemical imidization method to produce a series of the unsymmetrical aromatic polyimides. The polyimides were characterized by solubility tests, viscosity measurements, IR, 1H NMR, and 13C NMR spectroscopy, X-ray diffraction studies, and thermogravimetric analysis. The polyimides obtained had inherent viscosities ranged of 0.38-0.58 dL/g, and were easily dissolved in common organic solvents. The resulting strong and flexible PI films exhibited excellent thermal stability with the decomposition temperature (at 5% weight loss) of above 505 °C and the glass transition temperature in the range of 230-299 °C. Moreover, the polymer films showed outstanding mechanical properties with the tensile strengths of 41.4-108.5 MPa, elongation at breaks of 5-9% and initial moduli of 1.15-1.68 GPa.  相似文献   

18.
A novel aromatic triol was synthesized and polycondensed with various diacid chlorides resulting in the preparation of a series of hydroxy-terminated hyperbranched polyamide-esters without gelation. Structure and degree of branching of the ensuing polymers were confirmed by FTIR, 1H and 13C NMR analyses. These thermally stable polymers were found to be soluble in aprotic solvents. Inherent viscosities and Tg values lie in the range of 0.15-0.21 dL/g and 74-112 °C, respectively.  相似文献   

19.
Six new structurally different bismaleimides or bisnadimides based on 2,5-bis(4-aminophenyl)-3,4-diphenylthiophene (BADT) were synthesized and characterized by infrared (IR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. Chain-extension of several bismaleimides was accomplished by incorporating various imide, amide, and urea groups. The bismaleimide and bisnadimide prepared by reacting BADT with maleic or nadic anhydride, respectively, were soluble in various organic solvents. The monomers were thermally polymerized or by a Michael reaction with certain aromatic diamines. Curing behavior was investigated by differential thermal analysis (DTA). The thermal and thermo-oxidative stability of polymers was evaluated by dynamic thermogravimetric analysis (TGA) and isothermal gravimetric analysis (IGA). The polymers derived from bismaleimide of BADT as well as from the bismaleimides chain-extended by imide groups were stable up to 355–392°C in N2 or air and afforded anaerobic char yield 66–74% at 800°C. The polymers obtained by curing the bismaleimide-diamine adducts showed a relatively lower thermal stability.  相似文献   

20.
A new oxypyrone diamine, 2,6-bis(4-aminophenyl)-3,5-dimethyltetrahydro-4H-pyran-4-one (DAPP), was prepared from 4-nitrobenzaldehyde and 3-oxa-n-pentane in a two-step reaction with a high yield and a high purity. Aromatic polyamides were obtained from this novel condensation monomer and several diacid chlorides through the conventional low-temperature solution method in N,N-dimethylacetamide. Polycondensation results were consistent with a high reactivity for DAPP because high yields and high molecular weight polyamides were obtained with inherent viscosities up to 1.8 dL/g. The reactivity of DAPP was also estimated with theoretical calculations from computer programs for molecular simulation, with orbital and charge factors considered. The polymers showed improved solubility in organic solvents, relative to conventional wholly aromatic polyamides, and high glass-transition temperatures (from differential scanning calorimetry) over 270 °C. However, the thermal resistance, as estimated by thermogravimetric analysis, was lower than that of conventional aromatic polyamides; nevertheless, decomposition temperatures well beyond 300 °C were observed in nitrogen and air. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1825–1832, 2001  相似文献   

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