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1.
Polymers having thioether, thiolester, and amide linkages in each repeating unit of a polymer main chain were prepared by the polyaddition reaction of pseudoxazolones (2-isopropylidene-4-alkyl-3-oxazolin-5-ones) and dimercaptans. The polymers had inherent viscosities in a range of 0.08–0.22 and gave transparent films by solution casting.  相似文献   

2.
Polythiazolines     
Polythioureas having pendant hydroxyl groups were prepared by the polyaddition reaction of bisaminoalcohols and diisothiocyanates. The polythioureas had inherent viscosities in the range of 0.22–1.08 dl/g and gave transparent films by solution casting. These polythioureas were converted to polythiazolines by treatment with poly(phosphoric acid) or to poly(thiazoline–oxazolines) by treatment with a mixture of poly(phosphoric acid) and a polar solvent.  相似文献   

3.
A series of polyarylates having inherent viscosities of 0.4–1.1 dL/g was prepared by the two phase polycondensation of 1,1,3-trimethyl-3-(4-chloroformylphenyl)indanecarbonyl chloride with various bisphenols in an organic solvent–aqueous alkaline solution system in the presence of a phase transfer catalyst. Similarly, copolyarylates of high molecular weights were prepared from a mixture of the phenylindanedicarbonyl chloride, terephthaloyl chloride, and 2,2-bis(4-hydroxy-phenyl)propane. All the polyarylates were characterized by their amorphous nature and high solubility in organic solvents. They gave transparent and tough films by the solution casting. The films had tensile strength of 33–46 MPa, elongation at break of 3–16%, and tensile modulus of 1.2–1.6 GPa. These polyarylates had glass transition temperatures in the range of 205–310°C, and began to decompose at ca. 350°C in air.  相似文献   

4.
Novel, soluble aromatic polyamides and copolyamides containing tetraphenylethylene units were prepared by the low temperature solution polycondensation of 1,1-bis(4-aminophenyl)-2,2-diphenylethylene and aromatic diamines with various aromatic diacid chlorides. Highmolecular-weight polyamides having inherent viscosities of 0.6–1.5 dL/g and number-average molecular weight above 21000 were obtained quantitatively. These polymers were readily soluble in various solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide (DMAc), and dimethyl sulfoxide and gave pale yellow, transparent, flexible films by casting from DMAc solution. The polymers had glass transition temperatures between 290 and 340°C, and started to lose weight around 400°C, with 10% weight loss being recorded at about 470°C in air.  相似文献   

5.
Poly(carbamoyl disulfides) have been prepared for the first time by the stepwise condensation of chlorocarbonylsulfenyl chloride with dithiols and diamines. The polymers obtained in high yields had inherent viscosities up to 1.86. The properties of the polymers depended primarily on the kind of diamines used. Some of the polymers gave transparent, tough films from chloroform solution. The polymer films decomposed by ultraviolet irradiation with liberation of carbonyl sulfide. All the polymers gradually became brittle during storage for 6–8 months under diffused light.  相似文献   

6.
A new series of fluorine-containing polyarylates were synthesized by interfacial or high-temperature solution polymerization of 1,1-bis(4-hydroxyphenyl)-1-phenyl-2,2,2-trifluoroethane with six aromatic diacyl chlorides. These polyarylates had inherent viscosities ranging from 0.47 to 1.37 dl/g that corresponded to weight-average and number-average molecular weights (by gel permeation chromatography) of 35,800-72,400 and 30,700-67,700, respectively. All polymers were highly soluble in a variety of solvents, and could afford tough, transparent, and colorless films via solution casting. The glass-transition temperatures of the polymers ranged from 209 to 271 °C. All of them did not show significant decomposition below 450 °C in both nitrogen and air atmospheres.  相似文献   

7.
An investigation of the reaction of 4-phenyl-3-buten-4-olide with benzylamine was conducted as a model for the polymerization, and some ethers and acidic solvents were found to be favorable reaction media for formation of the ring-opened amide as the sole product. By using m-cresol as the polymerization medium, linear polyamides having inherent viscosities up to 0.67 were readily prepared by the ring-opening polyaddition of 4,4′-oxydi-p-phenylenebis(3-buten-4-olide) with aliphatic diamines at room temperature. These polymers were soluble in m-cresol and gave transparent, flexible films by the solution casting technique. They did not show any melt temperature, and began to decompose at around 200°C, both in air and under nitrogen.  相似文献   

8.
Aromatic polyamides (aramids) having pendant t-butyl group were synthesized by the direct polycondensation of 5-t-butylisophthalic acid with various aromatic diamines in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. The aramids having inherent viscosities of 0.6–2.4 dL/g were obtained in quantitative yields. These polymers were readily soluble in various solvents such as NMP,N,N-dimethylacetamide, dimethyl sulfoxide, and pyridine, and gave transparent, tough and flexible films by casting from the NMP solutions. The aramids had glass transition temperatures between 250 and 330°C, and started to lose weight around 350°C, with 10% weight loss being recorded at about 450°C in air.  相似文献   

9.
Aromatic polyamides (aramids) having inherent viscosities of 0.5–1.10 dL/g were prepared by the direct polycondensation of 1,1,3-trimethyl-3-(4-carboxyphenyl)indane-5-carboxylic acid with various aromatic diamines using triphenyl phosphite and pyridine as the condensing agents. Copolyamides were also prepared by a similar procedure from a mixture of the phenylindane diacid, terephthalic acid, and p-phenylenediamine. Almost all of the aramids were soluble in a variety of solvents such as N-methyl-2-pyrrolidone, pyridine, and m-cresol, and afforded transparent and tough films by the solution casting. These aramids and copolyamides had glass transition temperatures in the range of 290–355°C, and started to lose weight at 340°C in air.  相似文献   

10.
Aromatic poly(sulfenyl thiocarbonates) have been synthesized by the interfacial polycondensation of bis(dithiocarbonyl chlorides) with bisphenols. Bisphenols having the hydroxyl groups on separate rings gave polymers in high yields. The inherent viscosities of the polymers ranged from 0.22 to 0.51. In general, they were soluble in chloroform, sym-tetrachloroethane, hexamethylphosphoramide, m-cresol, and dimethylformamide and formed transparent tough films on evaporation of chloroform solutions. Almost all of the polymers were amorphous and gave melt-spun fibers. The polymer films decomposed upon ultraviolet irradiation with liberation of carbonyl sulfide.  相似文献   

11.
New polyamides, polyimides, and a polyamide-imide containing ester linkages were prepared by the reaction of trimethylene glycol di-p-aminobenzoate with terephthaloyl chloride, isophthaloyl chloride, adipoyl chloride, pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, and trimellitoyl chloride. the low temperature solution and interfacial polymerization techniques were utilized to prepare the above-mentioned polymers. the polymers thus prepared were found to be soluble in solvents like DMAC and DMSO and had inherent viscosities in the 0.15-0.60 range. the polyimides prepared formed transparent and flexible films.  相似文献   

12.
Random and block disiloxane-containing copolyamides were prepared through one- and two-step procedures, respectively, by the low temperature solution polycondensation in chloroform containing triethylamine hydrochloride starting from 1,3-bis(3-aminopropyl)tetramethyldisiloxane, an aromatic diamine [3,4'-diaminodiphenyl ether (ODA) or m-phenylenediamine], and isophthaloyl chloride. The random copolyamides exhibited composition-dependent single glass transition temperature (Tg), and gave transparent and tough films by solution casting or hot pressing. The ODA-based block copolyamides had two Tg's, and the solvent-cast transparent films exhibited microphase separated morphology. The block copolymers gave better quality films than the single-phase random copolymers. © 1992 John Wiley & Sons, Inc.  相似文献   

13.
2,6-Bis-(2,5-dioxo-tetrahydro-N-(4-carboxyphenyl)pyrrol-3-yl)-pyrrolo[3,4-f]isoindole-1,3,5,7-teraone, a chiral diacid, was prepared from pyromellitic anhydride and L-aspartic acid in a three steps reaction pathway. The polycondensation reactions of the monomer with aromatic diamines were carried out in direct condensation reaction conditions. The synthesized poly(amide-imide)s had inherent viscosities in the range of 0.30–0.80 dl/g. Identification of all of the products were performed by conventional analytical techniques such as TLC, IR and 1H NMR/13C MR spectroscopy. Thermoanalytical techniques (TGA/DSC) showed useful levels of thermal stability, associated with relatively high glass transition temperatures and carbonized residues in excess of 40% at 600°C for the synthesized polymers. Amorphous morphology was obtained based on XRD patterns and DSC traces. The polymers were soluble in a variety of polar organic solvents and afforded transparent and relatively flexible to brittle films by solution casting.  相似文献   

14.
Polycondensation of 2,5-bis(4-chloroformyl)-3,4-diphenylthiophene ( I ) with various bisphenols afforded tetraphenylthiophene-containing aromatic polyesters by the interfacial or solution polycondensation method. Polyamide–esters were obtained from I and aminophenols by means of the interfacial technique. These polymers had inherent viscosities of 0.4–0.8 dL/g. All the polymers were readily soluble in various organic solvents, and could be cast into transparent and flexible films. Their glass transition temperatures were in the range of 235–335°C. These polymers did not lose weight below 400°C in either air or nitrogen.  相似文献   

15.
The polymerization of N,N′-bis(trimethylsilyl)-substituted aromatic diamines with 4-chloroformylphthalic anhydride in various solvents at a temperature range between 10 and 70°C afforded polyamide-amic acid trimethylsilyl esters having inherent viscosities of 0.8–1.4 dL/g. Transparent and flexible films of the silylated precursor polymers were obtained by casting directly from the polymer solutions. Desilylation of the silylated polymers with methanol resulted in the formation of the corresponding polyamide-amic acids. Subsequent thermal imidization of the silylated precursor polymers with the elimination of trimethylsilanol afforded yellow, transparent, and tough films of the aromatic polyamide-imides. The thermal conversion of the silylated precursor polymer to polyamide-imide proceeded almost as rapidly as that of the corresponding polyamide-amic acid prepared by a conventional method from the parent aromatic diamine and 4-chloroformylphthalic anhydride.  相似文献   

16.
Aromatic poly(o-hydroxy amide)s having inherent viscosities of 0.6–2.2 dL/g were readily synthesized by the low-temperature solution polycondensation of N,N′,O-tris(trimethylsilyl)-substituted 2,4-diaminophenol with aromatic dicarboxylic acid chlorides in various organic solvents. The viscosity values were much higher than those of the polymers obtained by a conventional method using parent 2,4-diaminophenol. Subsequent thermal cyclodehydration of the poly(o-hydroxy amide)s at 280°C under vacuum afforded the corresponding aromatic polyamide-benzoxazoles. Most of the poly(o-hydroxy amide)s dissolved readily in amide-type solvents, whereas the polyamide-benzoxazoles were quite insoluble in organic solvents. The polyamide-benzoxazoles, which gave yellow, transparent, and tough films, had glass transition temperatures of 260–300°C and were stable up to 400°C in air.  相似文献   

17.
Silylated aromatic polyureas were synthesized by the polyaddition of N,N′-bis(trimethylsilyl)-substituted aromatic diamines to aromatic diisocyanates in various organic solvents at a temperature ranging from 30 to 100°C. Colorless and transparent films of the silylated polyureas were obtained by casting directly from these solutions in a dry nitrogen atmosphere. The silylated polyureas thermally decomposed at around 200°C and were easily desilylated with alcohol to convert to almost amorphous aromatic polyureas having inherent viscosities of 0.4–1.0 dL/g. The polyureas exhibited better solubility in organic solvents such as N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and dimethyl sulfoxide and had somewhat lower thermal decomposition temperatures (around 300°C) than the polyureas prepared by a conventional method from the parent aromatic diamines and diisocyanates.  相似文献   

18.
New aromatic poly(amide-imide)s with high inherent viscosities were prepared by direct polycondensation reaction of diimide-diacid (I) and aromatic diamines using triphenyl phosphite in N-methyl-2-pyrrolidone (NMP)/pyridine solution containing dissolved CaCl2. The bis(3-trimellitimidophenyl) phenyl phosphine oxide (I) was readily obtained by the condensation reaction of bis(3-aminophenyl) phenyl phosphine oxide (BAPPO) with trimellitic anhydride. The resulting poly(amide-imide)s showed high thermostability. Their decomposition temperatures at 10% weight loss in nitrogen atmosphere were above 532 °C and the anaerobic char yield at 800 °C ranged from 56% to 74%. Almost all the poly(amide-imide)s showed high glass transition temperature above 233 °C by differential scanning calorimetry (DSC) measurements. These polymers were readily soluble in various organic solvents and by their casting into transparent, tough and flexible films can be easily achieved.  相似文献   

19.
New aromatic polyethers having inherent viscosities of 0.43–0.91 dL/g were synthesized by the phase-transfer catalyzed polycondensation of tetrafluoroisophthalonitrile with various hisphenols in a nitrobenzene-water system. All the polyethers were amorphous and soluble in N-methyl-2-pyrrolidone and nitrobenzene. They were cast into transparent and flexible films from the solutions. These polymers had glass transition temperatures around 130°C and dia not lose weight below 400°C in either air or nitrogen.  相似文献   

20.
2,6-Bis(4-aminophenoxy)naphthalene (2,6-BAPON) was synthesized in two steps from the condensation of 2,6-dihydroxynaphthalene with p-chloronitrobenzene in the presence of potassium carbonate, giving 2,6-bis(4-nitrophenoxy)naphthalene, followed by hydrazine hydrate/Pd—C reduction. A series of new polyamides were synthesized by the direct polycondensation of 2,6-BAPON with various aromatic dicarboxylic acids in the N-methyl-2-pyrrolidone (NMP) solution containing dissolved metal salts such as CaCl2 or LiCl using triphenyl phosphite and pyridine as condensing agents. The polymers were obtained in quantitative yields with inherent viscosities of 0.62–2.50 dL/g. Most of the polymers were soluble in aprotic dipolar solvents such as N,N-dimethylacetamide (DMAc) and NMP, and they could be solution cast into transparent, flexible, and tough films. The casting films had yield strengths of 84–105 MPa, tensile strengths of 68–95 MPa, elongations at break of 8–36%, and tensile moduli of 1.4–2.1 GPa. The glass transition temperatures of the polyamides were in the range 155–225°C, and their 10% weight loss temperatures were above 505°C in nitrogen and above 474°C in air. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2147–2156, 1997  相似文献   

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