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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.
Tri-n-butylphosphine-catalyzed polyadditions of activated internal diynes (bifunctional β-substituted propiolate, 1B and 1C ) with diols are described. Although a terminal bispropiolate ( 1A ) could not produce soluble polymers, with secondary diols, the polyaddition of 1B or 1C with primary as well as secondary diols gave corresponding polymers ( 3 , only composed of E isomeric units) in high yield. The rate of the present polyaddition was estimated by a model reaction of benzyl alcohol with methyl 2-heptynoate ( 4 ), from which the introduction of alkyl groups at the β-position of propiolate moieties was found to decrease the rate of the reaction by 80 times. Furthermore, the rate-determining step on this polymerization system was speculated to be a protonation step of zwitterionic intermediates with protons from diols. © 1996 John Wiley & Sons, Inc.  相似文献   

3.
The ring-opening polyaddition reaction of N,N′-disubstituted bisisomaleimides with various diamines in N-methyl-2-pyrrolidone at room temperature afforded polymaleamides having inherent viscosity up to 0.7 in almost quantitative yield. These polymers are a new class of homopolymaleamides and ordered alternating copolymaleamides. Almost all of the polyamides were soluble in a wide range of solvents such as dimethylsulfoxide, dimethylacetamide, m-cresol, and formic acid. They did not show any melt temperature, and began to decompose at a temperature ranging between 200 and 300°C.  相似文献   

4.
The ring-opening polyaddition reaction of N,N′-disubstituted bisphthalisoimides with various diamines in amide-type solvents at room temperature afforded polyphthalamides having inherent viscosity of up to 0.26 in excellent yields. Some of the polymers thus obtained are a new class of ordered alternating copolyphthalamides. These polyamides were soluble in polar aprotic solvents, as well as in acidic solvents. They showed relatively low melt temperature in the range of 120–220°C and further low level of thermal stability.  相似文献   

5.
A solution polyaddition procedure was applied to prepare furanic polyacylsemicarbazides based on 2,2′-isopropylidene-bis(5-(2-furoyl) hydrazide) and aliphatic or aromatic diisocyanates. Model compounds were prepared to facilitate the synthesis and the characterization of the polymers. A systematic study of reaction parameters (the nature of the organic phase, the temperature, the reaction time, and the concentration of monomers) was carried out. High MW polymers were obtained after 12 h reaction at 20°C with 0.2 M monomer solutions in dimethylacetamide. In fact, the polyacylsemicarbazides obtained had inherent viscosities ranging from 0.63 to 0.85 dL/g. There showed good solubility in aprotic polar solvents. The 1H and 13C-NMR spectra were consistent with the expected structures. These furan-based polyacylsemicarbazides are thermally stable up to 290°C, but exhibit a complex thermal behavior. This was explained by the cyclohydration of acylsemicarbazide groups into NH-substituted oxadiazoles, resulting in rigid and high melting polymers, less stable, however, than conventional aromatic polyoxadiazoles.  相似文献   

6.
Soluble brominated poly(arylene ether)s containing mono‐ or dibromotetraphenylphenylene ether and octafluorobiphenylene units were synthesized. The polymers were high molecular weight (weight‐average molecular weight = 115,100–191,300; number‐average molecular weight = 32,300–34,000) and had high glass‐transition temperatures (>279 °C) and decomposition temperatures (>472 °C). The brominated polymers were phosphonated with diethylphosphite by a palladium‐catalyzed reaction. Quantitative phosphonation was possible when 50 mol % of a catalyst based on bromine was used. The diethylphosphonated polymers were dealkylated by a reaction with bromotrimethylsilane in carbon tetrachloride followed by hydrolysis with hydrochloric acid. The polymers with pendant phosphonic acid groups were soluble in polar solvents such as dimethyl sulfoxide and gave flexible and tough films via casting from solution. The polymers were hygroscopic and swelled in water. They did not decompose at temperatures of up to 260 °C under a nitrogen atmosphere. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3770–3779, 2001  相似文献   

7.
Poly(thioether amide)s containing pyridine moieties in their backbone were obtained by the polyaddition of 2,6-bis(acrylamido)pyridine (2,6-BAAP), derived from 2,6-diaminopyridine and acryloyl chloride, with an aromatic or aliphatic dithiol. The influence of various reaction conditions on the polyaddition was investigated in comparison with the polyaddition of 1,3-bis (acrylamido)benzene (1,3-BAAB). 2,6-BAAP gave the polymer even in the absence of any initiator at lower temperatures while 1,3-BAAB did not, which was attributable principally to intramolecular base catalysis of the pyridine moieties. Basic additives effectively promoted the reaction rate and increased the chain length. Those facts and NMR of the resulting polymers indicated Michael-type polyaddition. The polymers from 2,6-BAAP were amorphous and gave transparent and tough films having a high refractive index exceeding 1.7. GPC and DSC characterizations were also made. © 1993 John Wiley & Sons, Inc.  相似文献   

8.
Radical ring‐opening polyaddition of bifunctional vinyloxirane with multifunctional thiols was investigated. The polyaddition proceeded smoothly via the ring‐opening reaction of the oxirane moiety to afford the corresponding networked polymers bearing vinyl ether and sulfide moieties in the main chain. The thermal properties of the networked polymers and volume changes upon the polyaddition were investigated. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 783–788  相似文献   

9.
Although the reaction of caffeine with hydrogen peroxide/hydrochloric acid or nitric acid and then with ammonia has been known to give a purple coloration (Murexide reaction), the use of hydrazine instead of ammonia is found to provide no purple coloration. The reaction of caffeine with hydrogen peroxide/hydrochloric acid and then with hydrazine hydrate afforded a yellow reaction mixture, from which 4-methyl-6-(N-methylcarbamoyl)-3,5-dioxo-2,3,4,5-tetrahydrotriazine 9 , oxalyl hydrazide 10 and hydroxylamine hydrochloride were isolated. The reaction of caffeine with nitric acid and then with hydrazine hydrate furnished a yellow reaction mixture, from which 8-amino-1,3,7-trimethyl-2,6-dioxo-1H,3H,7H-xanthine 11, 9 and hydroxylamine nitrate were isolated. Compound 9 was clarified to be produced from 3-hydroxy-4,6-dimethyloxazolo[4,5-d]pyrimidine-2,5,7(3H,4H,6H)-trione 3 and 1,3-dimethylalloxan 7 by the ring transformation with hydrazine.  相似文献   

10.
Fully aromatic polyquinazolinediones (IV) of high molecular weight were obtained by thermal cyclodehydration of aromatic poly(uredio acids) (III) prepared by the polyaddition reaction of 4,4′-diaminobiphenyl-3,3′-dicarboxylic acid (I) with aromatic diisocyanates (II). From the kinetic study of reactions of model systems (anthranilic acid with phenyl isocyanate) in the presence of a variety of basic catalysts, it was established that tertiary amines had the highest catalytic activity for the formation of ureido linkage. The optimum polymerization conditions were determined by the study of reaction variables such as monomer concentration, polymerization temperature, monomer ratio, and catalyst concentration. The effect of polarity and purity of organic solvents and reactants was also studied.  相似文献   

11.
An analytical method, referred to as "derivatization-electron probe X-ray micro-analysis (XMA)", has been developed to determine the distribution of a small amount of the functional groups in a polymer. The suitable conditions for the derivatization reaction with epoxy groups, which contribute to the hardening reactions of polymers, were investigated. It was found that epoxy groups in polymers were derivatized selectively using gas-phase esterification with hydrochloric acid (HCI). The most suitable amount of HCl in a 50 ml vial was 300 microl. After setting a sample in the vessel without directly contacting the reagent, by reacting the reagent and the sample at 25 degrees C for 1 h, the highest reaction yield and selectivity were obtained. By derivatization-XMA using this reaction condition, the measurement of the distribution of epoxy groups in the polymer became feasible. Actual applications to a depth analysis of epoxy groups in the hardened acrylic coating and epoxy resin proved that this method is useful for the characterization of polymers and for the study of the hardening reaction of polymers.  相似文献   

12.
The ring-opening polyaddition of 2,2′-disubstituted bis(3-buten-4-olides) with aliphatic diamines in m-cresol at room temperature afforded in quantitative yields polyamides with a pendant ketone moiety having inherent viscosities of up to 0.7. On the other hand, the polymerization in m-cresol at 80°C with acidic catalysts and at 160°C without any catalyst yielded directly polypyrrolones, a novel class of polyheterocycles. The cyclodehydration of the open-chain polyamides to polypyrrolones was also achieved by simply treating the polyamide films with methanolic hydrochloric acid at room temperature. Both of the polymers were generally soluble in hot polar solvents such as dimethylformamide, m-cresol, and nitrobenzene. The polypyrrolones began to lose weight gradually at around 250°C in nitrogen as determined by thermogravimetric analysis, while the thermograms in air showed an appreciable weight increase at about 230°C.  相似文献   

13.
New reactive polymers with pendant halomethyl groups were successfully synthesized by polyaddition reactions of bis(epoxide)s with bis(chloroacetoxy)ester such as 1,4-bis [(chloroacetoxy)methyl]benzene (BCAMB) or 1,4-bis[(bromoacetoxy)methyl]benzene (BBAMB) using quaternary onium salts or crown ether complexes as catalysts. The polyaddition reaction of diglycidyl ether of bisphenol A (DGEBA) with BCAMB proceeded very smoothly with high yields (83–96%) by the addition of quaternary onium salts such as tetrabutylphosphonium bromide (TBPB) or crown ether complexes such as 18-crown-6/KBr as catalysts to produce high molecular weight polymers, although the reaction occurred without any catalyst to give low molecular weight polymer in low yield at 90°C for 48 h. It was also found that the reaction proceeded smoothly in aprotic polar solvents such as N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc) to produce high molecular weight polymers. Polyaddition reactions of DGEBA or digylcidyl ether of ethylene glycol (DGEEG) with BBAMB, other bis(chloroacetoxy)esters or bis(bromoacetoxy)esters using TBPB in DMAc also proceeded smoothly to give the corresponding polymers. The resulting poly(ether-ester)s contain reactive halomethyl groups as side chains, which were introduced during main chain formation. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3791–3799, 1997  相似文献   

14.
Radical polyaddition of bis(α-trifluoromethyl-β,β-difluorovinyl) terephthalate [CF2C(CF3)OCOC6H4COOC(CF3)CF2] (BFP) with diformylalkanes to produce fluorinated polymer bearing ketone-carbonyl groups in main chain is described. The radical additions of hexanal, pentanal and benzaldehyde with 2-benzoxypentafluoropropene [CF2C(CF3)OCOC6H5] were examined as model reactions to yield the corresponding addition product with hexanal and pentanal in high yields, and no product with benzaldehyde. The addition of acyl and hydrogen was found to take place to perfluoroisopropenyl group. The results of the model reactions suggested that the reaction might be applicable to polyaddition to produce polymers with diformylalkanes. The results of polyaddition of BFP with glutaraldehyde under the emulsion polymerization condition showed that the polymer of Mn=4.8×103 was obtained in fairly high yields. This might be a novel preparation method of polymers bearing fluorinated polyketone structure.  相似文献   

15.
Poly(amido‐amine)s carrying primary amino groups as side substituents have been obtained by polyaddition of N‐triphenylmethyl‐monosubstituted 1,2‐diaminoethane (TPHMAE) to 2,2‐bisacrylamido acetic acid or 1,4‐bisacryloylpiperazine and subsequent removal of the protecting triphenylmethyl group by treating the resultant polymers with aqueous hydrochloric acid. Soluble polymers can be also obtained directly by the polyaddition of monoprotonated 1,2‐diaminoethane to 2,2‐bisacrylamido acetic acid in the presence of a limited amount of added acetic or hydrochloric acid. The resultant polymers are of a higher molecular weight than the corresponding ones prepared from TPHMAE. By adding a limited amount of N‐triphenylmethyl‐monosubstituted 1,2‐diaminoethane to the monomer mixtures leading to poly(amido‐amine)s with a recognised potential as nonviral vectors, such as ISA 23 and ISA 1, a controlled number of pendant primary amino groups have been introduced. By this procedure, ISA 23 and ISA 1 become suitable as polymer carriers for carboxylated drugs as well as amenable to the labelling techniques by fluorescent probes commonly employed for proteins.

Formation of monoprotected primary diamines.  相似文献   


16.
Polyamideamines with a sequence of two amide and one amine linkage in a main chain were synthesized from the polyaddition of 2-isopropylidene-4-alkyl-3-oxazolin-5-ones and primary diamines. The polyaddition reaction proceeded through 1,4-conjugate addition of an amine group to 3-oxazolin-5-one and subsequent ring opening of the intermediate addition product with another amine. Although aliphatic diamines gave oily polymers, xylylenediamines afforded amorphous solid polymers. The reduced viscosities and polymer melt temperature of the polymers were 0.05–0.12 and 90–130°C., respectively.  相似文献   

17.
A monomer of the AB‐type and a bifunctional comonomer of the AA‐type containing two 2‐oxazoline rings and a biphenyl structural unit were prepared from the corresponding carboxylic acids via their esterification and subsequent amidation with an aminoalcohol. The cyclization of an amide to 2‐oxazoline structure was achieved by treatment with thionyl chloride followed by liberation of the free base with sodium hydrocarbonate in an aqueous solution. The prepared monomers were used for the polyaddition polymerization of the AB‐type monomer having a 2‐oxazoline and phenol group bound on adjacent rings of the biphenyl structure in solution. The monomer of the AA‐type was used for AA+BB‐type polyaddition reactions with aliphatic dicarboxylic acids. Both types of polymerizations have been performed in melt and in solution. The structures of the polymers were determined, and the thermal properties of the polymers were evaluated. Liquid‐crystalline (LC) structures of the prepared polymers were observed by DSC measurements and optical microscopy. The polyaddition reactions of the monomers containing a 2‐oxazoline ring and a biphenyl unit represent a new efficient way for the preparation of a biphenyl unit containing poly(ether amide)s and poly(ester amide)s. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

18.
The reaction of hydride polyaddition of methylhydridesiloxane and methylhydridesiloxane-dimethylsiloxane oligomers to unsaturated carbocyclic compound - tricyclodecadiene, at the various ratio of initial compounds, in the presence of platinum hydrochloric acid has been investigated. It was shown that hydrosilylation reaction proceeds both to 1.2 and 9.10 positions and by intermolecular with formation of branching systems. The polyorganosiloxanes with tricyclodecenyl fragment in the side chain, completely soluble in organic solvents were synthesized. For fully characterization of hydride addition of methylhydridesiloxane to tricyclodecadiene, by quantum-chemical half empiric AM1 method, for all initial, intermediate and final products, in modelling reaction of hydrosilylation of methyldimethoxysilane to tricyclodecadiene, the heats of formations (ΔHf), change of energy (ΔH) of the system depending on the change of distance (RC-Si) between C-Si bonds, also the charges values (q) on the atoms, dipole moments (µ) and bonds orders (Pij) are calculated. It was concluded, that the course of hydride addition of modelling reaction of methyldimethoxysilane to tricyclodecadiene energetically is more favourable by 9.10-addition. The hydride polyaddition reaction order, activation energies and rate constants were found. The synthesized oligomers were characterized by 1H and 13C NMR, FTIR, thermogravimetry, gel permeation chromatography, differential scanning calorimetry and wide angle X-ray methods.  相似文献   

19.
We examined lactone-formation reaction of oligomers and polymers of N-acetylneuraminic acid in diluted hydrochloric acid solution and found that the time course of the lactonization reaction was easily traced by capillary electrophoresis. The reaction proceeded more rapidly with increasing the molecular mass of oligomers because the conformation of inner units became rigid and more favorable for the formation of lactone linkage. Present results obtained using capillary electrophoresis will be useful in understanding of physical and chemical properties of oligo/polysialic acids.  相似文献   

20.
With tetrahydrofuran as a solvent and pyridium p‐toluenesulfonate as a catalyst, the hydroxyalkyl vinyl ethers 2‐hydroxyethyl vinyl ether (2E), 4‐hydroxybutyl vinyl ether (4B), and 6‐hydroxyhexyl vinyl ether (6H) underwent step‐growth self‐polyaddition, generating polymers with an acetal main‐chain structure. The molecular weight of the resulting polymers increased gradually during the initial polymerization period at room temperature. However, decomposition occurred after about 22–24 h, and the presence of a large amount of catalyst accelerated the latter process. The three monomers exhibited different polymerization capabilities. In contrast to the smooth polymerization of 6H, cyclization side reactions usually took place during the polymerizations of 4B and 2E, which resulted in low polymer yields and low molecular weights because of the formation of unreactive small cyclic acetals. In the self‐polyaddition of 4B, this side reaction was greatly restricted at high concentrations of the monomer. Higher temperatures (60–70 °C) remarkably accelerated the self‐polyaddition process to produce polymers with high molecular weights. However, the polymerizations at high temperatures had to be terminated within about 2 h to avoid the severe decomposition of the polymers. Copolymers were also obtained via the copolyaddition of any two of the monomers. The easiness of the incorporation of the monomers into the copolymers was in the sequence 6H > 4B > 2E. Poly(6H), poly(4B), poly(2E), and the copolymers possessed different hydrophilicities and were stable in basic, neutral, and even weak acidic media but exhibited degradation in the presence of a strong acid. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3751–3760, 2000  相似文献   

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