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1.
A series of phosphorous-containing aliphatic polyesters were synthesized by high-temperature solution condensation of 2-(6-oxido-6H-dibenz〈c,e〉〈1,2〉oxaphosphorin-6-yl)-1,4-hydroxyethoxy phenylene (III) with various aromatic acid chlorides in o-dichlorobenzene. All polyesters are amorphous and readily soluble in many organic solvents such as DMAc, NMP, DMSO, and o-dichlorobenzene at room temperature or upon heating. These polyesters are thermally quite stable. The glass transition temperatures of these aliphatic polyesters ranged from 126.6 to 162.2°C. The degradation temperatures (Td onset) in nitrogen ranged from 424 to 448°C, and the char yields at 700°C are 20–32%. The activation energies of degradation ranged from 160.9 to 226.0 kJ/mol. The LOIs of these polyesters ranged from 36 to 43. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3051–3061, 1998  相似文献   

2.
Two series of phosphorus‐containing aromatic poly(ester amide)s with inherent viscosities of 0.46–3.20 dL/g were prepared by low‐temperature solution polycondensation from 1,4‐bis(3‐aminobenzoyloxy)‐2‐(6‐oxido‐6H‐dibenz〈c,e〉〈1,2〉oxaphosphorin‐6‐yl)naphthalene and 1,4‐bis(4‐aminobenzoyloxy)‐2‐(6‐oxido‐6H‐dibenz〈c,e〉〈1,2〉oxaphosphorin‐6‐yl)naphthalene with various aromatic diacid chlorides. All the poly(ester amide)s were amorphous and readily soluble in many organic solvents, such as N,N‐dimethylformamide, N,N‐dimethylacetamide (DMAc), and N‐methyl‐2‐pyrrolidone (NMP). Transparent, tough, and flexible films of these polymers were cast from DMAc and NMP solutions. Their casting films had tensile strengths of 71–214 MPa, elongations to break of 5–10%, and initial moduli of 2.3–6.0 GPa. These poly(ester amide)s had glass‐transition temperatures of 209–239 °C (m‐series) and 222–267 °C (p‐series). The degradation temperatures at 10% weight loss in nitrogen for these polymers ranged from 462 to 489 °C, and the char yields at 800 °C were 55–63%. Most of the poly(ester amide)s also showed a high char yield of 35–45%, even at 800 °C under a flow of air. The limited oxygen indices of these poly(ester amide)s were 35–46. © 2002 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 459–470, 2002; DOI 10.1002/pola.10129  相似文献   

3.
Thirteen phosphorus-containing flame retardants were synthesized in this work. The solubilities of flame retardant [(6-oxide-6H-dibenz[c,e][1,2]oxaphosphorin-6-yl)-methyl]-butanedioic acid (DDP) in selected solvents are measured. TGA measurements of the 13 phosphorus-containing flame retardants were carried out and thermal stabilities of three flame-resistant PET (FRPET) resins were investigated. A FRPET incorporated by DDP with terephthalic acid and ethylene glycol reported in literature was also discussed and compared. The thermal stability of the FRPET is improved by the incorporation of phosphorus-containing flame retardants. The LOI values of all phosphorus-containing polyesters are higher than 27%. The improvement of the flame-resistant ability is due to the formation of the char that is not only caused by the existence of phosphorus elements in the resin but also by the relative large number of carbon atoms of the phenyl group in the flame retardants.  相似文献   

4.
2-(6-oxido-6H-dibenz(c,e)(1,2)oxaphosphorin-6-yl)-1,4-naphthalenediol (DOPONQ) was prepared by the addition reaction of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) with 1,4-naphthoquinone. The phosphorus-containing diol (DOPONQ) was used as a reactive flame retardant by an advancement reaction with the diglycidyl ether of bisphenol-A epoxy (DGEBA) resin at various stoichiometric ratios. DOPONQ-containing advanced epoxy was separately cured with various dicyanate esters to form flame-retardant epoxy/cyanate ester systems. The effect of the phosphorus content and dicyanate ester structure on the curing characteristic, glass transition temperature, dimensional stability, thermal stability, flame retardancy, and dielectric property was studied and compared with that of the control advanced bisphenol-A epoxy system. The DOPONQ-containing epoxy/cyanate ester systems exhibited higher glass transition temperatures as well as better thermal dimensional and thermal degradation stabilities. The flame retardancy of the phosphorus-containing epoxy/dicyanate ester system increased with the phosphorus content, and a UL-94 V-0 rating could be achieved with a phosphorus content as low as 2.1%.  相似文献   

5.
A series of polyester‐amides that contain phosphorus were synthesized by low temperature solution condensation of 1,4‐bis(3‐aminobenzoyloxy)‐2‐(6‐oxido‐6H‐dibenz〈c,e〉〈1,2〉oxaphosphorin‐6‐yl) phenylene (III) with various aromatic acid chlorides in N‐methyl pyrrolidone (NMP). All polyester‐amides are amorphous and readily soluble in many organic solvents such as dimethylacetamide (DMAc), NMP, dimethylsulfoxide, and dimethylformamide at room temperature or on heating. Light yellow and flexible films of these polyester‐amides could be cast from the DMAc solutions. The polymers with an inherent viscosity of 0.26–0.72 dL/g were obtained in quantitative yields. These polyester‐amides have good mechanical properties (G′ of ∼ 109 Pa up to 200°C) and good thermal and flame retardant properties. The glass transition temperatures of these polyester‐amides ranged from 250 to 273°C. The degradation temperatures (Td 5%) in nitrogen ranged from 466 to 478°C and the char yields at 800°C were 59.6–65.2%. The limiting oxygen indexes of these polyester‐amides ranged from 35 to 43. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 891–899, 1999  相似文献   

6.
This work examines the curing kinetics, thermal properties, and decomposition kinetics of diglycidyl ether of bisphenol A (DGEBA) epoxies with three different curing agents, 2-(6-oxido-6H-dibenz(c,e)(1,2)oxaphosphorin-6-yl)-1,4-naphthalenediol (ODOPN), bisphenol A (BPA), and bisphenol S (BPS). The differential scanning calorimetry curing study reveals that the curing kinetics of the DGEBA/ODOPN epoxy is first order, independent of the scan rate. The ODOPN-containing epoxy, unlike the conventional BPA one, includes a phosphorus-containing bulky pendant aromatic group and results in an increase in the glass-transition temperature of 83 K, the char yield increases by a factor of 3, and the limiting oxygen index values increase from 23 to 27. For the BPS system, the glass-transition temperature increased slightly, and both the char yield and the limiting oxygen index value increased insignificantly when the test was conducted in air. Finally, the thermogravimetric analysis decomposition study in N2 from Ozawa's analysis demonstrates that the DGEBA/BPS epoxy has the highest activation energy, followed by the regular DGEBA/BPA system, and lastly the DGEBA/ODOPN has the lowest activation energy. The low activation energy for the ODOPN system is attributed to the initial decomposition of the phosphorus compound in the formation of an insulating layer.  相似文献   

7.
A new phosphinate-substituted bisphenol A, 1,1-bis(4-hydroxyphenyl)-1-(6-oxido-6H-dibenz <c,e> <1,2> oxaphosphorin-6-yl)ethane (1), was prepared by a facile, one-pot procedure. In addition, a reaction mechanism for the preparation of (1) was proposed. Based on (1), a diglycidyl ether derivative (2) was prepared and cured by commercially-available curing agents. The structures of (1-2) were confirmed by IR, high-resolution mass, 1-D and 2-D NMR spectra. Properties such as glass transition temperature, coefficient of thermal expansion, thermal decomposition temperature, and flame retardancy of the resulting thermosets were evaluated and compared with those of the thermosets of diglycidyl ether of bisphenol A. The resulting epoxy thermosets show high Tg, low thermal expansion, good thermostability and excellent flame retardancy.  相似文献   

8.
In this study, two new thermotropic liquid crystalline phosphorus-containing polymers were prepared by polycondensation reaction of 1,4-phenylene-bis((6-oxido-6H-dibenz[c,e][1,2]oxaphosphorinyl)carbinol) with two different phosphonic dichlorides, namely ethyl dichlorophosphate and phenyl dichlorophosphate. The polymers were characterized by means of FT-IR, 1H NMR, differential scanning calorimetry, polarized light microscopy, wide-angle X-ray diffraction, and thermogravimetric analysis. Thermogravimetric analysis was performed in nitrogen atmosphere by heating the samples over a range of temperatures from 25° to 700°C using five different heating rates. The kinetic processing of data was achieved using the Freeman-Carroll, ASTM E1641, and Kissinger methods.  相似文献   

9.
阮超  杨荣  钟海艺  陈力  王玉忠 《高分子学报》2012,(10):1177-1182
以联苯二甲酸二甲酯、二甘醇和9,10-二氢-9-氧杂-10磷酰杂菲-对苯二酚二羟乙基醚(DOPO-HQ-HE)为单体,通过无规共聚合成了一种新型含磷液晶共聚酯(PDEBP).用1H-NMR对共聚酯的结构进行了表征,用TGA、DSC和POM对其热性能及液晶行为进行了研究.结果表明,阻燃单体DOPO-HQ-HE的引入不会降低共聚酯的热稳定性,含7.5 mol% DOPO-HQ-HE的共聚酯PDEBP7.5在700℃的氮气氛中的残余物(Wt700R)可达31.9 wt%,并且具有很好的阻燃性.DOPO-HQ-HE含量的增加对共聚酯的结晶性有较大的破坏,5 mol% DOPO-HQ-HE的共聚酯PDEBP5的清亮点温度为154.2℃,焓变为4.64 J/g,而PDEBP7.5在POM测试中在升温及降温过程中均难观察到液晶相的双折射现象.  相似文献   

10.
Transition metal ions (Pb2+, Zn2+, Cd2+, Co2+, Mn2+, Cu2+, Ni2+, Hg2+, Ag+, Fe3+) in water are used to quench emission of 2-(6-oxido-6H-dibenz 〈c,e〉 〈1,2〉 oxaphosphorin-6-yl)-1,4-phenylene-bis(p-pentyloxylbenzoate)s (MD5) with aggregation-induced emission enhancement (AIEE) in water-acetonitrile (AN) mixture (80:20 by volume). Among all metal ions, Fe3+ exhibits the highest quenching efficiency on AIEE of MD5 even when the concentration of Fe3+ is lower than 1×10−6 mol/L. The quenching efficiency of Hg2+ is lower than that of Fe3+ at the same concentration, though MD5 is used to detect Hg2+ efficiently, too. To other metal ions, low quenching efficiency has few relations with a wider concentration range. The UV absorbance spectra show only red shift of absorbance wavelength in the presence of Hg2+ and Fe3+, which indicates a salt-induced Jaggregation. SEM photos reveal larger aggregation and morphological change of nanoparticles of MD5 in water containing Hg2+ and Fe3+, which reduce the surface area of MD5 emission for further aggregation. The selective quenching effect of transition metal ions to emission of MD5 has a potential application in chemical sensors of some metal ions.  相似文献   

11.
Acid-catalyzed reaction of 6,10a-dihydroxy-3,4a,7,9-tetra(tert-butyl)-1,2,4a,10a-tetrahydrodibenzo-[b,e][1,4]dioxine-1,2-dione with 2-methylquinoline derivatives led to the formation of a previously unknown system 6-[(Z)-2-(quinolin-2-yl)-1-hydroxyethen-1-yl]pyran-2-one. The molecular structure of 3,5-di(tert-butyl)-6-[(Z)-2-(7,8-dimethyl-4-chloroquinolin-2-yl)-1-hydroxyvinyl]pyran-2-one was established by XRD method; the energy and structural characteristics of its isomers in the gas phase and in a polar solvent were calculated by quantumchemical methods (B3LYP/6-31G**).  相似文献   

12.
A new aromatic dicarboxylic acid, 1,4-bis (p-carboxyphenoxy)naphthyl ( 3 ), was synthesized by the reaction of p-fluorobenzonitrile with 1,4-naphthalenediol, followed by hydrolysis. Aromatic polyamides having inherent viscosities of 1.27–2.22 dL/g were prepared by the triphenyl phosphite activated polycondensation of diacid 3 with various aromatic diamines. Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents including N,N-dimethyl-acetamide (DMAc), N-methyl-2-pyrrolidone (NMP), and m-cresol. Transparent, tough, and flexible films of these polymers could be cast from the DMAc or NMP solutions. The cast films had tensile strengths ranging from 64–104 MPa, elongations-at-break from 6 to 10%, and initial moduli from 1.52 to 2.14 GPa. These polyamides had glass transition temperatures in the range of 195 to 240°C. Almost all polymers were thermally stable up to 400°C, with 10% weight loss being recorded above 480°C in air and nitrogen atmospheres. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2273–2280, 1997  相似文献   

13.
Acid-catalyzed reaction of 6,10a-dihydroxy-3,4a,7,9-tetra(tert-butyl)-1,2,4a,10a-tetrahydrodibenzo-[b,e][1,4]dioxine-1,2-dione with 4-chloro-2,7,8-trimethylquinoline gave previously unknown 3,6,8-tri-tert-butyl-3-[2-tert-butyl-5-(4-chloro-7,8-dimethylquinolin-2-yl)-4-hydroxy-3-oxopenta-1,4-dien-1-yl]-5-hydroxy-1,4-benzodioxin-2-one whose structure was determined by X-ray analysis. The energy and structure parameters of possible isomers of the product in the gas phase and in solution were estimated by PBE0/6-31G** quantum-chemical calculations.  相似文献   

14.
The two regioisomers 6-chloro-9-(1, 4-oxathian-3-yl)-9H-purine ( 5 ) and 6-chloro-9-(1,4-oxathian-2-yl)-9H-purine ( 6 ) were obtained when 3-acetoxy-1,4-oxathiane ( 3 ) was subjected to the acid-catalyzed fusion procedure; compound 3 was prepared by a Pummerer reaction with 1,4-oxathiane 4-oxide ( 2 ). The nucleoside analog 6 could he converted into the adenine derivative 7 and 9-(1,4-oxathian-2-yl)-9H-purine-6(1H)thione ( 8 ). The following nucleoside analogs have also been synthesized: 6-chloro-9-(1,4-dithian-2-yl)-9H-purine ( 13 ), 9-(1,4-dithian-2-yl)adenine ( 14 ), 9-(1,4-dithian-2-yl)-9H-purine-6(1H)thione ( 15 ), and 6-chloro-9-(1,4-dioxan-2-yl)-9H-purine ( 18 ).  相似文献   

15.
A series of new AB-type poly(etherimide)s having bisphenol-type moiety was prepared by the one-pot polyimidization using triphenylphosphite(TPP) in N-methyl-2-pyrrolidone(NMP)/pyridine solution at 150°C. Complete cyclodehydration was observed in the polymerizations as well as in model reactions. Polymers were obtained with inherent viscosities in the 0.27–0.49 dL/g range. The Mn and Mw/Mn of poly[4-(1,4-phenyleneoxy-1,4-phenylenehexafluoro-isopropylidene-1,4-phenylene)oxyphthalimide] (4d) with ηinh = 0.49 dL/g were 73,400 g/mol and 1.5, respectively. Most polymers could readily be dissolved in common organic solvents such as DMAc, NMP, and m-cresol. The polymer 4d was soluble even in chloroform. These polymers had glass transition temperatures between 205 and 235°C, and 5% weight loss temperatures in the range of 511–532°C in nitrogen. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3530–3536, 1999  相似文献   

16.
New cyclopentylidene ring-containing diamino-diesters, 1,1-bis(3-aminobenzoyloxy phenyl) cyclopentane, was prepared through reaction of cyclopentanone with two moles of phenol to yield 1,1-bis (4-hydroxy phenyl) cyclopentane (BHPP) (I), the resulting diol (I) on reaction with 3-nitrobenzoyl chloride in N,N-dimethyl acetamide (DMAc) and triethyl amine yield 1,1-bis(3-nitrobenzoyloxy phenyl) cyclopentane (II) which on finally reduced by catalytic hydrogenation in presence of 10% Pd/C in DMAc and stirred at room temperature under a 4 kg/cm2 hydrogen pressure yields 1,1-bis(3-aminobenzoyloxy phenyl) cyclopentane (III) (m-BABPP). The structure of novel m-diester-diamine was confirmed by FT-IR, 1H-NMR and 13C-NMR. A series of new m-poly (ester-amide)s and co-poly(ester-amide)s were synthesized by using the solution polycondensation method of novel diamine (III) with IPC and TPC in various mole proportion. These novel polymers were characterized by FTIR spectroscopy, solubility, inherent viscosity and thermal analysis and XRD studies. Inherent viscosities of these polymers were in the range 0.30 to 0.46 dL/g indicating moderate molecular weight built-up. These polymers exhibited excellent solubility in various polar aprotic solvents such as NMP, Pyridine. These polymers were partially soluble in DMSO, DMAc, DMF etc.

X-Ray diffraction pattern of polymers showed that introduction of cardo moiety containing ester linkage would disturb the chain regularity and packing, leading to amorphous nature. Thermal analysis by TGA showed excellent thermal stability of polymers. The structure -property correlation among these poly(ester-amide)s were studied, in view of these polymer's potential applications as processable high temperature resistance materials.  相似文献   

17.
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 Vc, Ve, and Vf exhibited good solubility in a variety of solvents such as N-methyl-2-pyrrolidinone (NMP), DMAc, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), pyridine, γ-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. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2815–2821, 1999  相似文献   

18.
4,4′-(1,4-Phenylenedioxy)dibenzoic acid (3), 4,4′-(2,5-tolylenedioxy)dibenzoic acid (Me-3), and 4,4′-(2,5-biphenylenedioxy)dibenzoic acid (Ph-3) were prepared by the nucleophilic substitution reaction of p-fluorobenzonitrile with hydroquinone, methylhydroquinone, and phenylhydroquinone, respectively, followed by alkaline hydrolysis. Several aromatic polyamides having inherent viscosities of 0.66–1.34 dL/g were directly prepared by a Yamazaki phosphorylation polyamidation technique from dicarboxylic acids 3, Me-3, and Ph-3, respectively, with aromatic diamines using triphenyl phosphite and pyridine as condensing agents. The solubility of methyl- or phenyl-substituted polyamides was remarkably enhanced when compared to that of nonsubstituted analogues. Most of the substituted polyamides revealed an amorphous nature and were readily soluble in a variety of organic solvents including N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide, dimethyl sulfoxide, and m-cresol. Transparent, flexible, and tough films of these polymers could be cast from the DMAc or NMP solutions. These films had tensile strength of 60–100 MPa, elongation to break of 6–11%, and tensile modulus of 1.68–2.25 GPa. The glass transition temperatures (Tg) of most polyamides could be determined by differential scanning calorimetry (DSC) and were in the range of 200–232°C. Thermogravimetric analyses established that these polymers were fairly stable up to 450°C, and the 10% weight loss temperatures were recorded in the range of 458–535°C in nitrogen and 468–528°C in air atmosphere. In general, the phenyl-substituted polyamides exhibited relatively higher Tg, thermal stability, and solubility. © 1996 John Wiley & Sons, Inc.  相似文献   

19.
Sulfinylation of o-nitrobenzamide and subsequent hetero Diels-Alder reaction gave a series of 2-(o-nitrobenzoyl)-1,2-thiazine-1-oxides. The 2-(o-nitrobenzoyl)-1,2-thiazine-1-oxides undergo a ring opening reaction with phenyl magnesium bromide to give allylic sulfoxides, which, after [2,3]-sigmatropic rearrangement and desulfurisation, furnish unsaturated vicinal N-(o-nitrobenzoyl)-1,2-amino alcohols. Oxidation of the alcohol and reductive ring closure gave a series of bicyclic 1,2,3,4-tetrahydro-1,4-benzodiazepin-5-ones, a subset of the ‘privileged’ 1,4-benzodiazepine structure. A 4-hydroxy-1,2,5-benzothiadiazepin-1,1-dioxide was synthesised by the same route starting from o-nitrobenzenesulfonamide.  相似文献   

20.
A straightforward and highly efficient series of new substituted 3-aryl-1,8-naphthyridine derivatives 3a–e, 4a–e, and 6a–e were synthesized. Condensation dissimilar quantities of 2-chloro-3-aryl-1,8-naphthyridine 1a–e with benzene-1,4-diamine 2 and sodium ethoxide refluxing in ethanol solvent yielded the compounds 3a–e and 4a–e. The 2-(4-((3-aryl-1,8-naphthyridin-2-yl)amino)phenyl)isoindoline-1,3-diones 6a–e were obtained by treatment of compounds 3a–e with phthalic anhydride 5 in refluxing N,N-dimethylformamide is described. All synthesized compounds evaluated for their antimicrobial activity. The structures of the compounds have been proven on the established of spectral (IR, 1H NMR, and 13C NMR) data and elemental analyses. The reaction will be characterized by good efficacy, easy workup, simple purification of the products, and availability of catalyst.  相似文献   

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