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1.
Polyaddition of bifunctional cyclic carbonates and diamines in ionic liquids proceeded smoothly to afford polyurethanes having hydroxyl groups in the side chain (i.e., poly(hydroxyurethane)). The reaction mixtures separated into ionic liquids and ionic composites consisting of poly(hydroxyurethane) and ionic liquids. The ionic composites originated from the interactions between hydroxyl groups in the side chains and the ionic liquids, confirmed by IR spectroscopic analysis. When the polyaddition was conducted in the mixed solvent consists of water and Nn‐butylimidazolium hexafluorophosphate. After the reaction, the polymer and the ionic liquid could be separated easily. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4629–4635, 2009  相似文献   

2.
The effect of various additives was examined for polyaddition of bifunctional cyclic carbonate and diamine giving poly(hydroxyurethane). Lithium chloride and lithium fluoride especially proved to be effective for the acceleration that resulted in giving polymers with higher molecular weights without coloration. The IR spectroscopic analysis of the mixtures of the additives and the carbonate monomer suggested that the acceleration with the lithium salts depends on the activation of the carbonyl group to enhance its electrophilicity. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6282–6286, 2005  相似文献   

3.
The cyclic amidinium iodide effectively catalyzed the ring‐expansion addition of epoxides with carbon dioxide under ordinary pressure and mild conditions to obtain the corresponding five‐membered cyclic carbonates in high yield. The novel triazole‐linked bifunctional five‐membered cyclic carbonate was synthesized successfully by the click reaction of the azide‐ and the alkyne‐substituted five‐membered cyclic carbonates under ambient temperature in high yield. The chemical structure of the novel bis(cyclic carbonate) was characterized by one‐ and two‐dimensional nuclear magnetic resonance spectra. The obtained bis(cyclic carbonate) was converted with commercially available diamines to poly(hydroxyurethane) containing triazole segment without catalyst in high yield. Analyses of the resulting poly(hydroxyurethane)s were performed by proton nuclear magnetic resonance, size exclusion chromatography, thermogravimetric analysis, and differential scanning calorimetry. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 986–993  相似文献   

4.
Polyurethanes bearing urethane groups in the side chains were prepared by the addition of isocyanates to the hydroxyl groups in poly(hydroxyurethane) prepared by the polyaddition of a bifunctional cyclic carbonate with 1,12‐diaminododecane. The urethanization proceeded quantitatively in the presence of a catalytic amount of di‐n‐butyltin dilaurate. The resulting polyurethane had a higher glass transition temperature than the original poly(hydroxyurethane), although its esterified product had a lower glass transition temperature. The urethanization with 3‐(triethoxysilyl)propyl isocyanate also proceeded effectively to afford both soluble and insoluble polymers, depending on the reaction conditions. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3408–3414, 2007  相似文献   

5.
A bifunctional five‐membered cyclic carbonate was synthesized from carbon dioxide and diglycidyl terephthalate, and its polyaddition with alkyl diamines were carried out in DMF at room temperature to obtain the corresponding poly(hydroxyurethane)s with Mn s in the range of 6300–13200 in good yields. The structures of the obtained polymers were confirmed by IR and NMR spectroscopy and their glass‐transition and decomposition temperatures were observed at 3–29 °C and 182–277 °C, respectively. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2375–2380, 2000  相似文献   

6.
A polyurethane bearing methacrylate groups through urethane linkages was prepared by the addition of 2‐methacryloyloxyethyl isocyanate to the hydroxyl groups in poly(hydroxyurethane) prepared by the polyaddition of a bifunctional cyclic carbonate with 1,12‐diaminododecane. The urethanization proceeded quantitatively in the presence of a catalytic amount of di‐n‐butyltin dilaurate at an ambient temperature, whereas a crosslinked product was obtained from the reaction at 60 °C. The resulting linear polyurethane, bearing a methacrylate structure, was thermally crosslinkable. Its radical copolymerization with vinyl‐type monomers afforded the corresponding crosslinked polymers, whose low glass transition temperatures suggested the flexibility of the polymer chains in the crosslinked product. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3400–3407, 2007  相似文献   

7.
Crosslinked poly(mercapto‐thiourethane) was employed as a precursor for graft copolymer synthesis. The crosslinked stem polymer ( 1 ) was easily prepared by polyaddition of a bifunctional dithiocarbonate and piperazine under air atmosphere via oxidative coupling of mercapto group. Polymerization of styrene and methyl methacrylate in the presence of 1 yielded the corresponding crosslinked graft copolymers with high grafting weight percentages (>1800%). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5097–5102, 2005  相似文献   

8.
The trifunctional five‐membered cyclic carbonate 2 and dithiocarbonate 3 were successfully synthesized by the reaction of trifunctional epoxide 1 with carbon dioxide and carbon disulfide, respectively. The crosslinking reactions of 2 with p‐xylylenediamine or hexamethylenediamine were carried out in dimethyl sulfoxide at 100 °C for 48 h to produce the corresponding crosslinked poly(hydroxyurethane)s quantitatively. The crosslinking reactions of 3 with both p‐xylylenediamine and hexamethylenediamine, followed by acetylation of thiol moiety, produced the corresponding crosslinked poly(thioester–thiourethane)s quantitatively. The obtained crosslinked poly(hydroxyurethane)s were thermally more stable than the analogous crosslinked poly(thioester–thiourethane)s, probably because of less thermal stability of thiourethane moiety than hydroxyurethane moiety. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5983–5989, 2004  相似文献   

9.
In the present study, the synthesis of bis(cyclic carbonate) from carbon dioxide and bisphenol A (or bisphenol S)-diglycidyl ether was investigated using quaternary ammonium salts as catalyst. Among the salts tested, the one having a larger alkyl group and more nucleophilic counter anion exhibited a better catalytic activity. Poly(hydroxyurethane)s were prepared by the polyaddition reaction of bis(cyclic carbonate) and diamine. The poly(hydroxyurethane) has shown higher thermal stability than conventional polyurethane, and is expected as novel reactive polyurethane. The miscibility of blends containing poly(hydroxyurethena) and poly(styrene-co-acrylonitrile)(SAN) has been also studied by the optical clarity method and DSC.  相似文献   

10.
The three‐component polyaddition of diamines, carbon disulfide (CS2), and diacrylates in water was successfully achieved without the use of a surfactant or catalyst. Appropriate reaction conditions (i.e., reaction temperature, reaction time, and CS2 feed) enabled the polyaddition of 1,3‐di‐4‐piperidylpropane ( 1a ), CS2, and 1,6‐hexanediol diacrylate ( 2a ) to afford the corresponding poly(dithiourethane‐amine) containing 83% of dithiourethane units in 84% yield. Polyaddition of other monomers also proceeded under the optimum conditions to afford various poly(dithiourethane‐amine)s. Unsuccessful results for polyaddition in organic solvents such as toluene, tetrahydrofuran, and N,N‐dimethylformamide revealed that the polyaddition is accelerated in water. The obtained poly(dithiourethane‐amine)s adsorbed Au (III) efficiently under acidic conditions, due to the strong interaction of the thiocarbonyl sulfur in the dithiourethane unit with Au (III). The poly(dithiourethane‐amine)s also showed selective adsorption for Au (III) from a mixture of metal ions [Au (III), Fe (III), Mn (II), and Zn (II)], which indicates their potential utilization for the collection of gold. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 845–851, 2010  相似文献   

11.
The addition reaction of spiro orthoesters (SOEs) with electrophiles accompanying ring-opening isomerization was investigated as a model reaction for polyaddition of bifunctional SOEs with bifunctional electrophiles. Among several electrophiles such as carboxylic acids and carboxylic anhydrides, acid halides showed particularly high reactivities to SOEs. An equimolar reaction of SOEs with acid chlorides took place selectively, leading to the corresponding 1 : 1 adducts. SOEs with seven-membered cyclic ether rings—1,4,6-trioxaspiro[5.6]undecane derivatives—showed higher reactivities than SOEs with six- and five-membered cyclic ether rings. The reaction accompanied zero shrinkage in volume. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4502–4509, 1999  相似文献   

12.
Various water‐soluble hyperbranched poly(ester amine)s were synthesized by the direct polyaddition of diamines to diacrylates in the absence of a catalyst. Each diamine contained a secondary amino group and a primary amino group such as 1‐(2‐aminoethyl)piperazine, N‐methyl‐1,3‐propanediamine, or N‐ethylethylenediamine. When the ratio of diacrylate to diamine was 1/1, no gelation was observed throughout the polymerization. When the ratio of diacrylate to diamine was 3/2, no crosslinking occurred in the diluted solution, whereas an insoluble network formed in the concentrated solution. Fourier transform infrared and mass spectrometry were used to investigate the reaction procedure. The secondary amino group of diamine reacted faster with the vinyl group of diacrylate; this resulted in the formation of the intermediate with an acrylate group and two active hydrogen atoms attached to a nitrogen atom. Further self‐polyaddition of the intermediate, a kind of AB2‐type monomer, gave the hyperbranched poly(ester amine). © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2340–2349, 2002  相似文献   

13.
Poly(thiourethane)s having a siloxane moiety in the side chain were synthesized with a 5‐membered cyclic dithiocarbonate (DTC) having a siloxane group as a building block. The synthetic pathway consisted of (1) an addition reaction of the DTC with diamines and (2) polyaddition reactions of the resulting dithiols with diisocyanates. The siloxane moiety in the polymer side chain underwent a self‐condensation reaction upon exposure to moisture, and this led to a successful crosslinking reaction of the poly(thiourethane). The crosslinking on a silicate surface was accompanied by condensation between the siloxane side chain of the polymer and the silanol group on the surface, giving the corresponding surface that was permanently coated with the crosslinked polymer. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6492–6502, 2005  相似文献   

14.
This article deals with the polyaddition of a novel bis(seven‐membered cyclic carbonate), 1,2‐bis[3‐(1,3‐dioxepan‐2‐one‐5‐yl)‐propylthio]ethane, with the diamines 4,9‐dioxa‐1,12‐dodecanediamine and p‐xylylenediamine. The polyaddition was carried out at 30–70 °C for 6–24 h in dimethyl sulfoxide to obtain the corresponding polyhydroxyurethanes with number‐average molecular weights of 10,900–35,700 in good yields. The reaction of a monofunctional seven‐membered cyclic carbonate, 5‐allyl‐1,3‐dioxepan‐2‐one (7CC), with monoamines was also carried out to examine the reactivity in comparison with that of six‐ and five‐membered cyclic carbonates. The reaction rate constants of 7CC with n‐hexylamine and benzylamine were estimated to be 48.5 and 11.0 L/mol · h, respectively, in dimethyl sulfoxide‐d6 (initial reagent concentration = 1 M) at 30 °C. The seven‐membered cyclic carbonate ring was 2.98 and 5.82 kcal/mol more strained than those of the six‐ and five‐membered cyclic carbonates, respectively, according to a semiempirical molecular orbital calculation with the PM3 Hamiltonian. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4091–4100, 2001  相似文献   

15.
Polyaddition of bifunctional spiro orthoesters (SOEs) with bifunctional acid chlorides was examined to develop zero‐shrinkage polymerization. The polyaddition afforded the corresponding polyether‐esters by repeating the addition reaction accompanying the double ring‐opening isomerization of the SOE moiety in a manner similar to the reaction of monofunctional SOEs with acid chlorides. The polyaddition accompanied a slight shrinkage or expansion in volume. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 68–73, 2000  相似文献   

16.
Novel hyperbranched poly(amido amine)s containing tertiary amines in the backbones and acryl as terminal groups were synthesized via the Michael addition polymerizations of trifunctional amines with twofold molar diacrylamide. The hyperbranched structures of these poly(amido amine)s were verified by 13C NMR (INVGATE). The polymerization mechanisms were clarified by following the polymerization process with NMR method, and the results show that the reactivity of secondary amine formed in situ is much lower than that of the secondary amine in 1‐(2‐aminoethyl) piperazine (AEPZ) ring and the primary amine. The secondary amine formed in situ was almost kept out of the reaction before the primary and secondary amines in AEPZ were consumed, leading to the formation of the AB2 intermediate, and the further reaction of the AB2 yielded the hyperbranched polymers. The molecular weights and properties of poly(amindo amine)s obtained were characterized by GPC, DSC, and TGA, respectively. Based on the reaction of active acryl groups in the polymers obtained with glucosamine, hyperbranched polymers containing sugar were formed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5127–5137, 2005  相似文献   

17.
New hybrid polyhydroxyurethane networks were quantitatively synthesized by radical polymerization of new hydroxyurethane methacrylate (HUMA) prepolymers. These HUMAs were synthesized in several steps. First, bis(cyclic carbonate) poly(propylene oxide) was reacted with two different diamines (ethylene diamine and 2,2′‐(ethylenedioxy)diethylamine) in excess. Then, these end‐functionalized hydroxyurethane prepolymers were converted into end‐functionalized hydroxyl prepolymers by ring opening of ethylene carbonate. Finally, a methacrylate function was grafted to the hydroxyl functions. All these steps were performed at room temperature. These prepolymers were thermally either homopolymerized or copolymerized using benzylmethacrylate or poly(ethylene oxide) bisphenol A dimethacrylate as comonomers, leading to new hybrid nonisocyanate polyurethane networks with various properties. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019  相似文献   

18.
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   

19.
Novel one-pot syntheses of sulfur-containing polymers from a bifunctional five-membered cyclic dithiocarbonate ( 1a ) were carried out. Polythiourethanes were obtained by the polyaddition of 4,4′-methylenebis(phenyl isocyanate), tolylene 2,6-diisocyanate, and hexamethylene diisocyanate with a dithiol ( 2a ) obtained by the reaction of 1a and benzylamine under mild conditions. Polythioesters were also obtained by the polycondensation of terephthaloyl and succinyl chlorides with 2a . Further, polythioether was obtained by the polycondensation of α,α′-dibromo-p-xylene with 2a . © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1189–1195, 1998  相似文献   

20.
A bifunctional cyclic five‐membered dithiocarbonate (DTC), having a bisphenol A structure, was found to be an effective accelerator for a epoxy–amine curing system comprised of bisphenol A diglycidyl ether and amine‐terminated polypropylene glycol. The acceleration effect was evaluated by monitoring the time‐dependence of the storage modulus of the reaction mixture with a dynamic mechanical analyzer. The reactions involved in the curing system were investigated in detail by performing a series of model reactions using the corresponding monofunctional monomers. This investigation revealed that (1) DTC reacted with amine rapidly, (2) the reaction afforded the corresponding adduct having a thiourethane and thiol moieties, and (3) the thiol reacted rapidly with epoxide. The thiourethane moiety incorporated into the resulting adduct effectively catalyzed the reaction of epoxide and amine, and this catalysis was the predominant mechanism for the acceleration effect arisen by the addition of DTC. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4606–4611, 2007  相似文献   

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