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1.
A novel polyaryloxydiphenylsilane was synthesized successfully by solution polycondensation of 2,2′-dimethyl-biphenyl-4,4′-diol with diphenyldichlorosilane and the catalyst triethylamine in toluene at 80 °C. Polymers with a relatively high inherent viscosity and yield were obtained when the reactions were carried out in aromatic and lipophilic solvents. The novel polyaryloxydiphenylsilane was soluble in chlorinated aliphatic hydrocarbons such as methylene chloride and chloroform as well as in polar solvents such as dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide and also in some common organic solvents such as benzene and toluene. However, it was insoluble in both aliphatic hydrocarbons as well as in alcoholic solvents. The polyaryloxydiphenylsilane began losing weight around 400 °C under a nitrogen atmosphere, and the 10% weight-loss temperature was 473 °C. The glass-transition temperature of the polyaryloxydiphenylsilane was 102 °C. The glass transition could be lowered by the copolymerization technique with 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane as an aromatic diol comonomer. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4591–4595, 1999  相似文献   

2.
New N-phenylated aromatic-aliphatic and all aromatic polyamides were prepared by the high-temperature solution polycondensation of 4,4′-dianilinobiphenyl with both aliphatic (methylene chain lengths of 6–11) and aromatic dicarboxylic acid chlorides. All of the aromatic-aliphatic polyamides and the wholly aromatic polyamides exhibited an amorphous nature and good solubility in amide-type and chlorinated hydrocarbon solvents, except for those aromatic polyamides containing p-oriented phenylene or biphenylylene linkages in the backbone; the latter were crystalline and insoluble in organic solvents except m-cresol. The N-phenylated aromatic-aliphatic polyamides and aromatic polyamides had glass transition temperatures in the range of 79–116°C and 207–255°C, respectively, and all the polymers were thermally stable with decomposition temperatures above 400°C in air. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2193–2200, 1998  相似文献   

3.
A novel synthetic method for soluble precursor polymers of poly(p‐phenylene vinylene) (PPV) derivatives by the palladium‐catalyzed three‐component coupling polycondensation of aromatic diiodides, aromatic bis(boronic acid) derivatives, and norbornadiene is described. For example, the polymerization of 1,4‐diiodo‐2,5‐dioctyloxybenzene, benzene‐1,4‐bis(boronic acid propanediol ester), and norbornadiene at 100 °C for 3 days provided a polymer consisting of the three monomer units in a 97% yield (number‐average molecular weight = 3100, weight‐average molecular weight/number‐average molecular weight = 1.37). A derivative of PPV was produced smoothly by the retro Diels–Alder reaction of the polymer both in a dodecyloxybenzene solution and in a film at 200 °C in vacuo. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3403–3410, 2005  相似文献   

4.
Addition reaction of (3-methyl-3-oxetanyl)methyl acetate (MOMA) with bis(4-mercaptophenyl) sulfide (BMPS) was examined in certain organic solvents. When the reaction of MOMA with BMPS was performed without any catalyst in hexamethylphosphoric triamide (HMPA) and N-methyl-2-pyrrolidone (NMP) at 130°C for 24 h, conversions of the corresponding adduct were 96 and 36%, respectively, which was confirmed by 1H-NMR spectra. On the other hand, when the reaction was carried out using tetraphenylphosphonium bromide (TPPB) as a catalyst under the same conditions, conversions of the adduct were 96 and 81% in HMPA and NMP, respectively. This result shows that although the addition reaction of oxetane compound with aromatic dithiol proceeds without any catalyst in HMPA, the reaction was strongly enhanced by adding TPPB in NMP. On the basis of the above results, polyadditions of bis((3-methyl-3-oxetanyl)methyl) terephthalate (BMOT) and bis((3-ethyl-3-oxetanyl)methyl) terephthalate with BMPS were performed using TPPB as the catalyst in NMP at 130°C for 24 h. As a result, the corresponding high molecular weight polymers 1 (Mn = 22,400) and 2 (Mn = 12,800) with pendant primary hydroxyl groups were obtained in 83 and 89% yields without any gel products, respectively. Furthermore, a low molecular weight oligomer was obtained from the polyaddition of BMOT with aliphatic dithiol, bis(mercaptomethyl)benzene, under the same reaction conditions. The catalytic activity on the polyaddition of BMOT with BMPS was also examined, and it was found that thermally stable TPPB and crown ether complexes at the reaction temperature (130°C) have higher catalytic activity than tetrabutylammonium bromide and tetrabutylphosphonium bromide to produce polymer 1 with high molecular weight. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2873–2880, 1998  相似文献   

5.
The polyaddition of bisphenol A diglycidyl ether with bis[4‐(P,P‐diphenylphosphinyloxy)phenyl] sulfone catalyzed by quaternary onium salt, such as tetrabutylammonium chloride afforded a new phosphorus‐containing polyether with good solubility in common organic solvents. Having studied various factors affecting the reaction, such as temperature, catalyst concentration, reaction time, etc., an appropriate polyaddition condition was suggested as using 5 mol % of suitable quaternary ammonium or phosphonium salt in polar solvent at 150°C within 25 h in an ampule for producing high molecular weight polymer. A number of polyethers bearing pendent phosphinate ester groups from the polyaddition of certain bis(epoxide)s and bis(phosphinate)s were synthesized under the above condition and characterized by GPC, IR, and NMR. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1009–1016, 1999  相似文献   

6.
Polyethers with unsymmetrical structures in the main chains and pendant chloromethyl groups were synthesized by the polyaddition of 3‐ethyl‐3‐(glycidyloxymethyl)oxetane (EGMO) with certain diacyl chlorides with quaternary onium salts or pyridine as catalysts. The unsymmetrical polyaddition of EGMO containing two different cyclic ether moieties such as oxirane and oxetane groups with terephthaloyl chloride proceeded smoothly in toluene at 90 °C for 6 h to give polymer 1 with a number‐average molecular weight (Mn) of 51,700 in a 93% yield when tetrabutylammonium bromide (TBAB) was used as a catalyst. The polyaddition also proceeded smoothly under the same conditions when other quaternary onium salts, such as tetrabutylammonium chloride, tetrabutylammonium iodide, tetrabutylphosphonium chloride, and tetrabutylphosphonium bromide, and pyridine were used as catalysts. However, without a catalyst no reaction occurred under the same reaction conditions. Polyadditions of EGMO with isophthaloyl chloride and adipoyl chloride gave polymer 2 (Mn = 28,700) and polymer 3 (Mn = 25,400) in 99 and 65% yields, respectively, under the same conditions. The chemical modification of the resulting polymer, polymer 1 , which contained reactive pendant chloromethyl groups, was also attempted with potassium 3‐phenyl‐2,5‐norbornadiene‐2‐carboxylate with TBAB as a phase‐transfer catalyst, and a polymer with 65 mol % pendant norbornadiene moieties was obtained. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 368–375, 2001  相似文献   

7.
A series of molecular‐weight‐controlled fluorinated aromatic polyimides were synthesized through the polycondensation of a fluorinated aromatic diamine, 1,4‐bis(4′‐amino‐2′‐trifluoromethylphenoxy)benzene, with 4,4′‐oxydiphthalic anhydride in the presence of phthalic anhydride as the molecular‐weight‐controlling and end‐capping agent. Experimental results demonstrated that the resulting polyimides could melt at temperatures of 250–300 °C to give high flowing molten fluids, which were suitable for melt molding to give strong and flexible polyimide sheets. Moreover, the aromatic polyimides also showed good solubility both in polar aprotic solvents and in common solvents. Polyimide solutions with solid concentrations higher than 25 wt % could be prepared with relatively low viscosity and were stable in storage at the ambient temperature. High‐quality polyimide films could be prepared via the casting of the polyimide solutions onto glass plates, followed by baking at a relatively low temperature. The molten behaviors and organosolubility of the molecular‐weight‐controlled aromatic polyimides depended significantly on the polymer molecular weights. Both the melt‐molded polyimide sheets and the solution‐cast polymer films exhibited outstanding combined mechanical and thermal properties. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1997–2006, 2006  相似文献   

8.
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   

9.
A novel fluorinated aromatic dianhydride, 4,4′‐[2,2,2‐trifluoro‐1‐(3‐trifluoromethyl‐phenyl)ethylidene]diphthalic anhydride (TFDA) was synthesized by coupling of 3′‐trifluoromethyl‐2,2,2‐trifluoroacetophenone with o‐xylene under the catalysis of trifluoromethanesulfonic acid, followed by oxidation of KMnO4 and dehydration. A series of fluorinated aromatic polyimides derived from the novel fluorinated aromatic dianhydride TFDA with various aromatic diamines, such as p‐phenylenediamine (p‐PDA), 4,4′‐oxydianiline (ODA), 1,4‐bis(4‐aminophenoxy)benzene (p‐APB), 1,3‐bis(4‐amino‐phenoxy)benzene (m‐APB), 4‐(4‐aminophenoxy)‐3‐trifluoromethylphenylamine (3FODA) and 1,4‐bis(4‐amino‐2‐trifluoromethylphenoxy)benzene (6FAPB), were prepared by polycondensation procedure. 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 CHCl3, THF, and acetone. Homogeneous and stable polyimide solutions with solid content as high as 35–40 wt % could be achieved, which were prepared by strong and flexible polyimide films or coatings. The polymer films have good thermal stability with the glass transition temperature of 232–322 °C, the temperature at 5% weight loss of 500–530 °C in nitrogen, and have outstanding mechanical properties with the tensile strengths of 80.5–133.2 MPa as well as elongations at breakage of 7.1–12.6%. It was also found that the polyimide films derived from TFDA and fluorinated aromatic diamines possess low dielectric constants of 2.75–3.02, a low dissipation factor in the range of 1.27–4.50 × 10?3, and low moisture absorptions <1.3%. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4143–4152, 2004  相似文献   

10.
Hyperbranched polymers consisting of aromatic or aliphatic polyether cores and epoxide chain‐end peripheries were prepared by proton transfer polymerization. AB2 diepoxyphenol monomer 1 proved to be well suited for the preparation of hyperbranched aromatic polymer 2 by this proton transfer polymerization. The use of chloride‐ion catalysis, rather than conventional base catalysis, for the preparation of polymers from diepoxyphenol 1 offered a unique method to control the ultimate molecular weight of the polymer product through variations of the initial concentration of monomer 1 in tetrahydrofuran. An alternative route to hyperbranched polyether epoxies made use of commercially available or easily prepared aliphatic monomers of the types AB2, AB3, and A2 + B3. Although these aliphatic polymerizations can be initiated with a base, chloride‐ion catalysis proved most effective for controlling the polymerization. The hyperbranched epoxies were characterized by NMR spectroscopy, gel permeation chromatography, and multi‐angle laser light scattering. Chemical modification of the polymers after polymerization was carried out via nucleophilic addition on the epoxide groups or derivatization of the hydroxy substituents within the hyperbranched polymer structure. Spectroscopic measurements suggested that some such ring‐opened materials may adopt reverse unimolecular micellar structures in appropriate solution environments. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4850–4869, 2000  相似文献   

11.
A series of polyamide-sulfonamides was synthesized by the interfacial polycondensation of m- and p-chlorosulfonylbenzoyl chlorides with aliphatic and aromatic diamines at room temperature. Most of the polymers obtained were high molecular weight, film-forming materials. They were all amorphous and were soluble in a wide range of acidic and basic solvents. Both aliphatic and wholly aromatic polyamide-sulfonamides showed initial breakdown in the range of 320–360°C under thermogravimetric analysis in a nitrogen atmosphere.  相似文献   

12.
The 1:1 stoichiometric salt monomer composed of squaric acid and bis(4‐aminophenyl) ether was successfully prepared and subjected to solid‐state thermal polycondensation under ordinary or high pressure, giving quite readily the aromatic polysquaramide with moderately high molecular weight. The polysquaramide formed was actually the random copolymer consisting of two component polymers, one of the main component being the polymer with a quasi‐aromatic mesoionic structure. The aromatic polysquaramide was crystalline and had a glass‐transition temperature of 245 °C, with an initial weight‐loss temperature of 400 °C in nitrogen. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2648–2655, 2002  相似文献   

13.
A Phenazasiline ring was incorporated into a polymer backbone by polycondensation of 2,8-dichloroformyl-5,10-dihydro-5-methyl-10,10-diphenylphenazasiline (V) with aromatic diamines or bisphenols, and phenazasiline-containing polyamides and polyesters were obtained. The polyamides were prepared by low-temperature solution polycondensation in N-methyl-2-pyrrolidone (NMP) in the presence of lithium chloride. The polyesters were synthesized by interfacial polycondensation in a mixture of 1,2-dichloroethane and aqueous alkali in the presence of tetrabutylammonium chloride as an accelerator. These reaction conditions gave the corresponding polymers with high viscosities. The phenazasiline-containing polyamides exhibited good solubilities in polar aprotic solvents such as dimethylformamide, dimethylacetamide, and NMP, and also in m-cresol, although the polyesters showed limited solubilities in organic solvents. Under nitrogen, the phenazasiline-containing polyamides and polyesters showed little degradation below 400°C and had good heat resistance.  相似文献   

14.
Synthesis of 1,5-bis(4-fluorobenzoyl)-2,6-dimethylnaphthalene ( 1 ), polycondensation of 1 with Bisphenol A, and properties of the obtained polymer were studied. Friedel–Crafts acylation of 2,6-dimethylnaphthalene with 4-fluorobenzoyl chloride in nitrobenzene selectivity afforded 1 in 82% yield. X-ray single crystal structural analysis of 1 confirmed that the dibenzoylation proceeded regioselectively and two methyl groups sterically inhibited the coplanarity of the two aromatic planes. The polycondensation of 1 with Bisphenol A in toluene/N-methyl-2-pyrrolidone (NMP) mixed solvent in the presence of excess potassium carbonate as a condensation reagent was carried out at 180°C for 4 h to quantitatively afford the corresponding poly(arylene ether-ketone) (PEK) 3 with high molecular weight (M?n~30,000) as a slightly yellow powder. As the reaction time was prolonged, both M?n and MWD of 3 increased and the solubility of 3 in chloroform clearly decreased. By GPC-LALLS, M?n of 3 obtained by the polycondensation for 16 h, was 85,000. The PEK 3 with high molecular weight was produced in a quantitative yield in a variety of solvents such as sulfolane. Water formed during the polycondensation hardly affected the yield and molecular weight of 3 , although a small molecular weight decrease took place. To evaluate the special effect of the methyl groups of 3 , polycondensation of 2,6-bis(4-fluorobenzoyl)naphthalene 2 with bisphenol A was carried out for comparison and the corresponding PEK 4 was quantitatively obtained. Whereas 3 was soluble in ordinary organic solvents such as tet-rahydrofuran (THF), chloroform, and NMP at room temperature, 4 was insoluble in most solvents except for strong acids such as conc. sulfonic acid. The polymer 3 showed high glass transition temperature (238°C) and 5% weight loss temperature (457°C). Casting of the polymer from THF solution gave a transparent, tough, flexible, and amorphous film. © 1995 John Wiley & Sons, Inc.  相似文献   

15.
Polymerization under the influence of boron trifluoride of 2-oxa-6-thia[3,3]spiroheptane gives two products: a linear polyether containing oxetane groups and a crosslinked polyether polysulfide. When the polymerization was carried out at ?3°C., up to 60% of soluble polysulfide is obtained. This does not prove that the thietane group polymerizes more rapidly than the oxetane group but rather that oxetane polymerization is inhibited by the presence of thietane groups. Polymerization under the influence of boron trifluoride etherate of 3,3-bis(mercaptomethyl)oxetane leads to a polyether containing free thiol groups. The degree of polymerization of the polymer, however, is low. In order to obtain higher degrees of polymerization several compounds with masked thiol groups were polymerized. 2-Oxa-6,7-dithia-6-thio[3,4]spirooctane and 2-oxa-6,8-dithia-7,7-dimethyl[3,5]-spirononane gave crosslinked products. The diacetate of 3,3-bis(mercaptomethyl)oxetane gave a linear polyether containing thiolacetate groups. Hydrolysis of this polymer leads to poly-3,3-bis(mercaptomethyl)oxetane with a softening temperature of 125–135°C.  相似文献   

16.
A new dicarboxylic acid having a kinked structure was synthesized from the condensation of 2,2′-bis(4-aminophenoxy)biphenyl and trimellitic anhydride. A series of biphenyl-2,2′-diyl-containing aromatic poly(amide-imide)s having inherent viscosities of 0.23–0.94 dL/g was prepared by the triphenyl phosphite activated polycondensation from the diimide-diacid II with various aromatic diamines in a medium consisting of N-methyl-2-pyrrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents including NMP and N,N-dimethylacetamide (DMAc). Transparent, flexible, and tough films of these polymers could be cast from DMAc or NMP solutions. The glass transition temperatures of these polymers were in the range of 227–261°C and the 10% weight loss temperatures were above 520°C in nitrogen. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1169–1177, 1998  相似文献   

17.
In this study, we synthesized polyphosphates with reactive pendant chloromethyl groups by an addition reaction of the diglycidyl ether of bisphenol-S (bisphenol-S epoxy, BPSE) with aryl phosphorodichloridates. The polyphosphates obtained were characterized by IR, 1H NMR spectra, elemental analysis, TGA, DSC, X-ray diffraction, and molar mass measurement. The polyaddition proceeded very smoothly in aromatic solvents catalyzed by quaternary ammonium or phosphonium salts such as tetrabutylammonium bromide and tetrabutylphosphonium bromide to produce a polymer having a high molecular weight. Polymer B, containing a bromine atom in the phenyl ring side chain, has the higher Tg value (Tg = 58°C) than the polyphosphate derived from phenoxy dichlorophosphate (PDCP). Polymer A derived from PDCP begins to lose 10% of its mass at 278°C, and the mass percentage remaining at 700°C is 44% under nitrogen. X-ray diffraction patterns revealed that all the subsequent polyphosphates are amorphous. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2365–2369, 1997  相似文献   

18.
A series of novel phosphorus‐containing polyesterimides were prepared from diols—a mixture of a new aromatic phosphorus‐containing bisphenol, namely 1,4‐bis[N‐(4‐hydroxyphenyl)phthalimidyl‐5‐carboxylate]‐2‐(6‐oxido‐6H‐dibenz<c,e><1,2>oxaphosphorin‐6‐yl)‐naphtalene, with aliphatic diols such as 1,3‐propanediol, 1,4‐butanediol, 1,5‐pentanediol, 1,6‐hexanediol, and 1,12‐dodecanediol—and an aromatic diacid chloride containing two preformed ester groups, namely terephthaloyl‐bis‐(4‐oxibenzoyl‐chloride), via high‐temperature polycondensation in o‐dichlorobenzene. The structures of monomers and polymers were verified by means of Fourier transform infrared (FTIR) spectroscopy and 1H NMR spectroscopy. The molar ratio of aromatic bisphenol to aliphatic diol was varied to generate a series of copolyesterimides with tailored physicochemical properties, structure–properties relationships being established. The effect of the phosphorus content on the thermal properties and the flame retardancy was evaluated by means of thermogravimetric analysis (TGA), TGA–FTIR, and scanning electron microscopy. The polymers were stable up to 340 °C showing a 5% weight loss in the range of 340–395 °C and a 10% weight loss in the range of 370–415 °C. The char yields at 700 °C were in the range of 13.6–38% increasing with the content of phosphorus‐containing bisphenol. The effect of the aliphatic content on the liquid crystalline behavior was investigated by polarized light microscopy, differential scanning calorimetry, and X‐ray diffraction. The transition temperatures from crystal to liquid crystalline melt were in the range of 209–308 °C. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010  相似文献   

19.
Wholly aromatic polysulfonamides of high molecular weight were prepared by the solution poly-condensation of aromatic disulfonyl chlorides with aromatic diamines in tetramethylene sulfone and substituted pyridines as the acid acceptor. Polysulfonamides with inherent viscosities as high as 1.2 were readily obtained by initiating polycondensation at a temperature of 5–10°C to control the side reactions. The polycondensation was fairly fast and was completed in 10 min at 60°C. All the aromatic polysulfonamides dissolved in a wide range of solvents, including acetone and tetrahydrofuran. These polymers were less thermally stable than the corresponding aromatic polyamides.  相似文献   

20.
Abstract

Aromatic/aliphatic regular copolyoxamides were prepared from aromatic diamine-oxamides and aliphatic diacid chlorides of various lengths of methylene groups by solution polymerization. The aromatic diamine oxamides, N,N′-bis(4-aminophenyl)oxamide and N,N′-bis(3-aminophenyl)oxamide were prepared and both were reacted with adipoyl chloride, suberoyl chloride, and sebacoyl chloride to form six new regular copolyoxamides. The polymers formed were soluble in sulfuric acid and also in some polar amide solvents. All copolyoxamides were high melting, with the meta-phenylene copolyoxamides melting from 346 to 373°C with decreasing length of the aliphatic diacid chloride, and the para-phenylene copolyoxamides decomposing prior to melting at near 400°C. The new polymers were characterized by UV spectrophotometry, differential scanning calorimetry, and thermal gravitational analysis.  相似文献   

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