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1.
A novel fluorinated aromatic diamine, bis[4-(4′-aminophenoxy)phenyl]-3,5-bis(trifluoromethyl)phenyl phosphine oxide, was synthesized. A series of new fluorinated polyimides containing phosphine oxide was prepared from the novel diamine with various commercially available aromatic dianhydrides. All the fluorinated polyimides show high glass transition temperatures, excellent thermal stability, and good solubility in common organic solvents. 相似文献
2.
A series of fluorinated polyimides were prepared from 1,1-bis[4-(4-aminophenoxy)phenyl]-1-phenyl-2,2,2-trifluoroethane with various aromatic tetracarboxylic dianhydrides via a conventional two-step procedure. These polyimides were amorphous in nature and afforded flexible and tough films. Some polyimides derived from less stiff dianhydrides were soluble in polar organic solvents. The glass-transition temperatures (T
g) of these polyimides ranged from 252 to 324C, and softening temperatures (T
s) stayed in the 254322C range. Decomposition temperatures (T
d) at 10% weight loss all occurred above 569C in both air and nitrogen atmospheres. For a comparative study, another series of analogous polyimides based on 1,1-bis[4-(4-aminophenoxy)phenyl]-1-phenylethane were also pepared and characterized. 相似文献
3.
2,2'-双[4-(3-氨基苯氧基)苯基]丙烷的合成 总被引:2,自引:0,他引:2
提出了以间二硝基苯和双酚A为原料经缩合和水合肼催化还原合成聚酰亚胺的单体2,2'-双[4-(3-氨基苯氧基)苯基]丙烷的新工艺,考察了各类工艺条件对目标产物收率的影响,得到最适宜反应条件,在优化条件下,总收率为85.5%.HPLC面积归一法测定目标产物纯度为99.97%,并用元素分析和红外光谱对目标产物进行了表征. 相似文献
4.
提出了以间二硝基苯和双酚A为原料经缩合和水合肼催化还原合成聚酰亚胺的单体2,2′-双[4-(3-氨基苯氧基)苯基]丙烷的新工艺,考察了各类工艺条件对目标产物收率的影响,得到最适宜反应条件,在优化条件下,总收率为85.5%。HPLC面积归一法测定目标产物纯度为99.97%,并用元素分析和红外光谱对目标产物进行了表征。 相似文献
5.
C. A. Terraza L. H. Tagle D. Mejías A. Tundidor-Camba P. Ortiz D. Muñoz F. Alvarez C. M. González-Henríquez 《Polymer Bulletin》2013,70(3):773-788
This study describes the synthesis and characterization of a new diamine; bis(4-(4-aminophenoxy)phenyl)methylphenylsilane, which by reaction with bis(4-carboxyphenyl)R1R2 silane derivatives, and following the methodology of the direct polycondensation, allowed the preparation of three new poly(amide)s (PAs). These polymers contain two diphenylsilane (Ph–Si–Ph) and oxyether moieties in their repetitive unit. The reaction to obtain the diamine starting from the respective diphenol was developed in two steps. The first step consisted on obtaining the dinitro derivative, bis(4-(4-nitrophenoxy)phenyl)methylphenylsilane, with a yield of 83 %. Then, this compound was reduced by reaction with hydrazine and Pd-activated carbon, with a yield of 67 % in the diamine. Both compounds were characterized by spectroscopic techniques (FT-IR, 1H, 13C and 29Si NMR). The synthesis of the PAs (PA-I, PA-II and PA-III) presented a yield of 35–79 %, glass transition temperature between 136 and 149 °C and inherent viscosities in the range 0.08–0.16 g/dL. PA-I and PA-III presented a transmittance value (at 400 nm) of 91 and 87 %, respectively, while PA-II only reached a value of 70 %. All these results were analysed in accordance with structural details of each repetitive unit and were also compared with those obtained from poly(amides) series not containing flexible elements in their chains. The TGA analyses demonstrated that the new polymers still maintain a high thermal resistance, despite the incorporation of the flexible units. 相似文献
6.
7.
A novel side-chain-sulfonated aromatic diamine of bis[4-(4-aminophenoxy)-2-(3-sulfobenzoyl)]phenyl sulfone (BAPSBPS) was synthesized. Sulfonated copolyimides were synthesized by random and sequenced block copolymerization of 1,4,5,8-naphthalene tetracarboxylic dianhydride, BAPSBPS and nonsulfonated diamine. They displayed good solubility in common aprotic solvents and high desulfonation temperature of 350 °C, suggesting the high stability of sulfonic acid groups. The reduced viscosity was in the range of 0.4-1.8 dl/g at 0.5 g/dl and 35 °C. Flexible and tough membranes with reasonably high mechanical strength were prepared. They showed anisotropic membrane swelling with larger swelling in thickness than in plane. They displayed reasonably high proton conductivity (σ), taking their lower ion exchanging capacity (IEC) into account. For example, the membrane with IEC of 1.54 mequiv/g showed σ values of 81 and 11 mS/cm in water and 70% RH, respectively, at 60 °C. 相似文献
8.
Several new polyamides were synthesized by direct polycondensation of the 1,3-bis[4-(4-aminophenoxy)phenyl]adamantane ( I ) with various dicarboxylic acids. The polyamides had inherent viscosities and number-average molecular weights (Mn) of 0.46–0.96 dL/g and 28,000–109,000, respectively. All polyamides III had good solubilities and were soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), and pyridine. Polyamides had tensile strengths of up to 72.3 MPa, elongation to breakage values of up to 10.2%, and initial modulus of up to 2.1 GPa. Their glass transition temperatures were found to be 228–269°C and 252–307°C using differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA), respectively. The melting temperature of IIIf was observed at 318°C using DSC. The temperatures of polyamides III at a 5% weight loss ranged from 395 to 435°C in air and from 400 to 450°C in a N2 atmosphere. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:315–321, 1998 相似文献
9.
A bis(ether amine) III-A containing a cyclohexane cardo group, 1,1-bis[4-(4-aminophenoxy)phenyl]cyclohexane, was synthesized and used as a monomer to prepare polyimides VI-A with six commercial dianhydrides via three different procedures. The intermediate poly(amic acid)s had inherent viscosities of 0.83–1.69 dL g−1 and were thermally or chemically converted into polyimides. Polyimides were also prepared by high-temperature direct polymerization in m-cresol and had inherent viscosities higher than the thermally or chemically cyclodehydrated ones. To improve the solubility of polyimides, six copolyimides were also synthesized from bis(ether amine) III-A with a pair of dianhydrides, which contained 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride or 4,4′-hexafluoroisopropylidenediphthalic anhydride. Series VI-A polyimides were characterized by the good physical properties of their film-forming ability, thermal stability, and tensile properties. A comparative study of the properties, with the corresponding polyimides derived from 2,2-bis[4-(4-aminophenoxy)phenyl]propane, is also presented. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2750–2759, 2001 相似文献
10.
A novel fluorinated aromatic diamine monomer, 1,1-bis[4-(4′-aminophenoxy)phenyl]-1-[3″,5″-bis(trifluoromethyl)phenyl]-2,2,2-trifluoroethane(9FTPBA), was synthesized by coupling 3′,5′-bis(trifluoromethyl)-2,2,2-trifluoroacetophenone with 4-nitrophenyl phenyl ether under the catalysis of trifluoromethanesulfonic acid, followed reduced by reductive iron and hydrochloric acid. A series of new fluorine-containing polyimides having inherent viscosities of 0.96-1.23 dl/g was synthesized from the novel diamine with various commercially available aromatic dianhydrides using a standard two-stage process with thermal imidization and chemical imidization of poly(amic acid) films. All the fluorinated polyimides were soluble in many polar organic solvents such as NMP, DMAc, DMF, and m-cresol, as well as some of low boiling point organic solvents such as chloroform and acetone. The polymer films have good thermal stability with the glass transition temperature of 223-225 °C, the temperature at 5% weight loss of 535-568 °C in nitrogen, and have outstanding mechanical properties with the tensile strengths of 68-89 MPa, initial moduli of 2.14-2.19 GPa, and elongations at breakage of 3.2-10.5%. 相似文献
11.
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13.
A new kind of aromatic unsymmetrical diamine monomer containing thiazole ring, 2-amino-5-[4-(4′-aminophenoxy)phenyl]-thiazole (APPT), was synthesized. A series of novel polyimides were prepared by polycondensation of APPT with various aromatic dianhydrides via one-step process. The resulting polyimides held inherent viscosities of 0.40-0.71 dL/g and were easily dissolved in strong dipolar solvents. Meanwhile, strong and flexible polyimide films were obtained, which had thermal stability with the glass transition temperatures (Tg) of 268.2-328.8 °C in nitrogen, the temperature at 5% weight loss of 452-507 °C in nitrogen and 422-458 °C in air, and the residue at 800 °C of 54.18-63.33% in nitrogen, as well as exhibited outstanding mechanical properties with the tensile strengths of 105.4-125.3 MPa, elongations at breakage of 6-13%. These films also held dielectric constants of 3.01-3.18 (10 MHz) and showed predominantly amorphous revealed by wide-angle X-ray diffraction measurements. 相似文献
14.
Summary
Bis(m-aminophenyl)diselenide was synthesized by
diazotation of m-nitroaniline followed by incorporation of
potassium selenium cyanate, and the reduction of the nitro
groups by addition of tin and concentrated HCl. This
dihydrochloride monomer was polymerised using ammonium
persulphate in 0.25 M HCl as oxidizing agent. Copolymers of
aniline with bis(m-aminophenyl)diselenide were prepared by
oxidation of diselenide and aniline mixtures, at several mole
ratios of aniline in the feed (f1), with
the same oxidizing agent. In the all the range of polymers
analysed there are more diselenide comonomer units than aniline
units. The polymer and copolymers were characterized by FTIR,
elemental analysis, thermal stability and electrical
conductivity, showing a high thermal stability, with a weight
loss of 10% at 400 °C and there is an important effect of groups
diselenide on the electrical properties, because conductivities
are highly modified when the substitution is in m-position in
the aniline ring. Therefore, it is necessary to add a high mole
ratio of aniline in the feed to obtain copolymers with
conductivities within the semi-conduction range. 相似文献
15.
16.
A new-type of tetraimide-dicarboxylic acid (I) was synthesized starting from the ring-opening addition of m-aminobenzoic acid (m-ABA), 4,4'-oxydiphthalic anhydride (ODPA), and 2,2-bis[4-(4-aminophenoxy)phenyl]sulfone (BAPS) at a 2:2:1 molar ratio in N-methyl-2-pyrrolidone (NMP), followed by cyclodehydration to the diacid I. A series of soluble and light-colored poly(amide-imide-imide)s (III
a-j) was prepared by triphenyl phosphite-activated polycondensation from the tetraimide-diacid I with various aromatic diamines (II
a-j). All films cast from DMAc had cutoff wavelengths shorter than 390 nm (379–390 nm) and had b
* values between 24.17–35.50; these polymers were much lighter in color than those of the alternating trimellitimide series. All of the polymers were readily soluble in a variety of organic solvents such as NMP, N,N-dimethyl acetamide, N,N-dimethylformamide, dimethyl sulfoxide, and even in less polar m-cresol and pyridine. Polymers III
a-j afforded tough, transparent, and flexible films, which had a strength at break ranging from 93 to 118 MPa, elongation at break from 8 to 11%, and initial modulus from 2.2 to 2.8 GPa, and some films showed yield points in the range of 95–111 MPa at stress–strain curves. The glass transition temperature of the polymers was recorded at 240–268°C. They had 10% weight loss at a temperature above 540°C and left more than 55% residue even at 800°C in nitrogen. 相似文献
17.
Photopolymerization of commercially available bisphenol A epoxy diacrylates with bis[4(2-hydroxy-3-acryloyloxypropoxy)phenyl]sulfide (BES-DA)—a monomer synthesized by our group in previous study was carried out. As this compound is solid at room temperature in its polymerization reactive diluent N-vinyl-2-pyrrolidone, which is also comonomer, has been applied. As a photoinitiator, 2-hydroxy-2-methyl-1-phenylpropan-1-one (Darocur 1173) was used. Thermal and mechanical properties of the obtained compositions were studied. The results show that thermal properties of both epoxy diacrylates improve with the increasing concentration of BES-DA. The addition of N-vinyl-2-pyrrolidone causes decrease of their storage moduli and glass transition temperatures. Simultaneously, it allows to increase the conversion of double bonds. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
18.
探讨采用微波辅助合成尾式卟啉(p-BrTMOPP)的制备工艺及其影响因素。以吡咯、对羟基苯甲醛和对甲氧基苯甲醛为原料,以丙酸为溶剂,制备得到p-HTMOPP;以1,4-二溴丁烷为原料,微波辅助加热条件下制备得到目标化合物尾式卟啉p-BrTMOPP;目标产物经过UV-vis、IR、ESI-MS等方法表征。在90℃、DMF溶剂条件下微波辐射加热30min,快速高效得到目标化合物,反应产率89.2%。和传统加热方法相比较,微波辅助合成尾式卟啉化合物明显缩短了反应时间,提高了反应效率。 相似文献
19.
20.
A series of new soluble poly(amide-imide)s were prepared from the diimide-dicarboxylic acid, 2,2-bis[4-(4-trimellitimidophenoxy)phenyl]norbornane, and various diamines by the direct polycondensation in N-methyl-2-pyrrolidinone containing CaCl2, using triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 1.01-1.42 dL g−1. Gel permeation chromatography (GPC) of the polymers showed number-average and weight-average molecular weight up to 67,300 and 118,000, respectively. The poly(amide-imide)s were amorphous and were readily soluble in various solvents such as N-methyl-2-pyrrolidinone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), pyridine, cyclohexanone and tetrahydrofuran. Tough and flexible films were obtained by casting their DMAc solution. The films had tensile strength of 89-110 MPa and a tensile modulus range of 1.8-2.2 GPa. The glass transition temperatures of the polymers were determined by DSC method and they were in the range of 265-295 °C. The polymers were fairly stable up to a temperature around or above 450 °C, and lose 10% weight in the range of 472-504 °C and 490-520 °C in nitrogen and air, respectively. 相似文献