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1.
This article describes a new, nonphosgene method for the synthesis of poly(bisphenol A carbonate) (PC). The method involves three steps: the reaction of an aliphatic diol with phenyl chloroformate to form an alkylene diphenyl dicarbonate, the reaction of the alkylene diphenyl dicarbonate with bisphenol A to produce an aromatic–aliphatic polycarbonate, and the thermal treatment of the polycarbonate at 180–210°C under a stream of nitrogen with Ti(OBu)4 to give PC and a cyclic alkylene carbonate. The method furnished low to moderate molecular masses of PC upon the complete elimination of the aliphatic moieties. The approach may be considered a new method, based on polycarbonate thermochemical degradation, for the synthesis of cyclic aliphatic carbonates. The obtained polymers were characterized by intrinsic viscosity and IR, 1H‐NMR, and 13C‐NMR spectroscopy. The thermal treatment step was conducted in a glass reaction tube at 180–210°C under a stream of nitrogen, and the reaction was completed by heating to 250°C. In the thermal treatment step, semisolid effluents composed of cyclic alkylene carbonates were formed and subsequently eliminated from the reaction mixture. Heating to 250°C under nitrogen or under a dynamic vacuum furnished the pure aromatic PC residue. This intrachange reaction provides a flexible method for the synthesis of polycarbonates with alkylene diols containing two or three methylene groups, from which the pure PC homopolymer can be prepared. The potential of this approach was demonstrated by the successful synthesis of PC homopolymer from five different polycarbonates with a bisphenol A unit linked to 1,2‐propylene, 1,3‐propylene, 2‐methyl‐1,3‐propylene, 2,2‐dimethyl‐1,3‐propylene, and 1,3‐butylene as the alkane chains. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

2.
In this study, we investigated the influence of the small molecule 4,4′‐thiobis(6‐tert‐butyl‐m‐methyl phenol) (AO300) on the miscibility of poly(isosorbide‐co‐1,4‐cyclohexanedimethanol carbonate) (IcC–PC) with bisphenol A polycarbonate (BPA–PC) through the formation of hydrogen‐bonding networks. Differential scanning calorimetry and morphological observation revealed that the initially, immiscible BPA–PC/IcC–PC blends become miscible through the addition of small molecules. Fourier transform infrared spectroscopy confirmed that intermolecular hydrogen bonds formed between the hydroxyl groups of AO300 and the carbonyl groups of the studied polycarbonates. These polycarbonates exhibited different hydrogen‐bonding behaviors and various degrees of glass‐transition temperature composition dependence. Dynamic mechanical analysis demonstrated that AO300 played an antiplasticization role in the BPA–PC/IcC–PC blends with improved storage moduli. To our knowledge, this article is the first to describe the miscibility of isosorbide‐based polycarbonate with BPA–PC. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44537.  相似文献   

3.
The curing and adhesive properties of one‐component epoxy resins containing Epikote 828 and diimines, derived from N,N′‐di(1‐ethylpropylidene)‐m‐xylylenediamine, N,N′‐di(1‐ethylpropylidene)‐1,3‐diaminomethylcyclohexane (2), and N,N′‐di(1,3‐dimethylbutylidene)‐m‐xylylenediamine, which were used as water‐initiated hardeners, were examined. Diethyl ketone‐based imines with a lower electron density on the C?N carbon were efficiently hydrolyzed and showed curing activity. 2, a novel diethyl ketone‐based diimine, served as an efficient latent hardener of the epoxy resin. A paste of the epoxy resin with 2 showed good storage stability at room temperature and good adhesive properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 878–882, 2003  相似文献   

4.
Cellulose flame retarded with an ammonia‐cured, polycondensed tetrakis(hydroxymethyl)phosphonium–urea derivative (as Proban CC®, Rhodia) phosphorylated by cyclic 1,3‐propanediol phosphoryl chloride and cyclic 2,2‐diethyl‐1,3‐propanediol phosphoryl chloride can give phosphorus levels up to 6.9% (w/w). Such high levels suggest up to 35.5% yields of reaction if the free secondary amine groups present in the crosslinked flame retardant and the C(6) primary hydroxyl groups are the assumed phosphorylation sites. The presence of substituted propanediol phosphonate moieties in the fibers significantly increases char formation above 400©C and scanning electron microscopy indicates that the char has an intumescent structure. The influence of the chemical structure of the propanyl moeity to the reaction extent of the possible phosphorylation sites and the char formation mechanism during thermal pyrolysis of the modified samples are discussed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3165–3172, 2003  相似文献   

5.
N‐Trimellitylimido‐L ‐isoleucine (3) was prepared from the reaction of trimellitic anhydride with L ‐isoleucine [L ‐2‐amino‐3‐methylvalerianic acid or (2S,3S)‐2‐amino‐3‐methyl‐n‐valerinic acid] in an N,N‐dimethylformamide solution at the refluxing temperature. The direct polycondensation reaction of the monomer imide diacid (3) with 1,4‐phenylenediamine, 4,4′‐diaminodiphenylmethane, 4,4′‐diaminodiphenylsulfone, diaminodiphenylether, 1,5‐naphthalendiamine, 2,4‐diaminotoluene, and 1,3‐phenylenediamine was performed in a medium consisting of triphenyl phosphite, N‐methyl‐2‐pyrolidone (NMP), pyridine, and calcium chloride. The polycondensation was performed under two different conditions: in one method, the reaction mixture was heated in an NMP solution at 60, 90, and then 130°C for different periods of time, and in the other method, the reaction mixture was refluxed only for 1 min in the same solvent. The resulting poly(amide imide)s (PAIs), with inherent viscosities of 0.21–0.37 dL/g, were obtained in high yields. All of these compounds were fully characterized by IR spectra, elemental analyses, and specific rotation measurements. Some structural characterizations and physical properties of these new optically active PAIs were examined. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 116–122, 2003  相似文献   

6.
Two novel cyclic‐amine monomers, i.e., 3‐allyl‐5,5‐dimethylhydantoin (ADMH) and 7,8‐benzo‐3 allyl‐1,3‐diazasprio[4.5]decane‐2,4‐dione (BADDD) were synthesized with good yields by reacting allyl bromide with 5,5‐dimethylhydantoin (DMH) and 7,8‐benzo‐1,3‐diazasprio[4.5]decane‐2,4‐dione (BDDD), respectively. The synthesized monomers were characterized by FTIR and 1H‐NMR spectra, and copolymerized with acrylonitrile (AN), vinyl acetate (VAC), and methyl methacrylate (MMA) in a small monomer ratio of ADMH and BDDD, respectively. The copolymers were characterized by FTIR, 1H‐NMR, and DSC studies. The N‐halamine derivatives of the corresponding copolymers were found to exhibit high antibacterial activities against Escherichia coli, and the antibacterial properties were durable and regenerable. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2460–2467, 2001  相似文献   

7.
In this study, a series of aromatic copolyesters P‐BPAx with lower melting temperature and higher glass transition temperature derived from hydroxybenzoic acid (HBA), 6‐hydroxy‐2‐naphthoic acid (HNA), bisphenol A (BPA) and terephthalic acid (TA) were synthesized via melt polymerization. The copolyesters were characterized by FTIR, solid state 13C NMR, DSC, TGA, polarized optical microscopy, X‐ray diffraction, and rheometry measurements. With addition of BPA, the resulting copolyester's melting temperature decreased from 260 to 221°C and its glass transition temperature increased from 70 to 135°C, compared with the parent copolyester P‐HBA70 (HBA/HNA copolymer). With exception of copolyester P‐BPA5.0 (225–280°C), the copolyesters could maintain liquid crystalline behavior in a broad temperature range from 230°C to higher than 410°C. The ability to form nematic liquid crystalline phase disappeared when BPA concentration became higher than 15 mol %. X‐ray diffraction analysis showed crystallinity decreased as the BPA content increased. A slightly distorted O" and a substantially distorted O′ orthorhombic phase was observed for P‐BPA2.5. Upon annealing at 220°C, the O" phase disappeared and the O′ phase became stronger gradually. Rheology study data showed the ability to process the copolyesters improved in those compositions containing <2.5 mol % BPA. Continuing to increase concentrations of BPA, they became intractable. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40487.  相似文献   

8.
A two-component initiator system based on the in situ cleavage of phenyl disulfide by a triarylphosphine has been developed for the ring-opening polymerization of cyclic bisphenol-A (BPA) carbonate oligomers. This development has potential use in composite applications such that the prepolymer can suitably wet the composite material before being converted to high-molecular-weight polymer. The initiator precursors (phenyl disulfide and triphenylphosphine) do not independently initiate significant ring-opening polymerization of the oligomeric cyclic BPA carbonate mixture. A mixture of cyclic BPA carbonate oligomers and one of the initiator components (phenyl disulfide), combined and heated at 300°C with a mixture of the cyclics and the other initiator component (triphenylphosphine), does produce a high-molecular-weight polymer (Mw = ∼ 70,000). The polymerization-initiating species is thought to be thiophenyltriphenylphosphonium thiophenoxide. The effects of concentration of the initiator components, reaction temperature, time, and so forth on polymerization were studied; in general, the degree of polymerization ranged from about 65 to 75%. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 2251–2255, 1997  相似文献   

9.
The catalytic alkoxycarbonylation of 1,2‐diols by (neocuproine)palladium(II) acetate (neocuproine=2,9‐dimethyl‐1,10‐phenanthroline) or palladium(II) acetate/(−)‐sparteine using N‐chlorosuccinimide as the oxidant affords cyclic carbonates. The oxidative carbonylation of diols proceeds under mild conditions, requiring only 1 atm of carbon monoxide, and produces cyclic carbonates in moderate to good yields. Both 1,2‐ and 1,3‐diols can be carbonylated using (neocuproine)Pd(OAc)2 and sodium dichloroisocyanuric acid, which serves as a competent oxidant and base for this system, to yield 5‐ and 6‐membered cyclic carbonates.  相似文献   

10.
Electrochemical preparation of poly(2‐bromoaniline) (PBrANI) and poly(aniline‐co‐2‐bromoaniline) [P(An‐co‐2‐BrAn)] was carried out in an acetonitrile solution containing tetrabutylammonium perchlorate (TBAP) and perchloric acid (HClO4). The cyclic voltammograms during the copolymerization had many features similar to those for the usual polymerization of aniline. The copolymer exhibits a higher dry electrical conductivity value than that of PBrANI and a lower one than that of PANI. The observed decrease in the conductivity of the copolymer relative to PANI is attributed to the incorporation of bromine moieties into the polyaniline chain. The structure and properties of the polymer and copolymer were elucidated using cyclic voltammetry (CV), FTIR, and UV‐vis spectroscopy. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2460–2468, 2003  相似文献   

11.
Novel molecular glasses (MGs) containing bisphenol A backbone (BPA‐6 and BPA‐10) are synthesized and characterized. BPA‐6 and BAP‐10 are excellent amorphous materials for extreme ultraviolet (EUV) patterning applications with good thermal stability (Td more than 160 °C). The MGs can be used as positive‐tone photoresists combined with triphenylsulfonium perfluoro‐1‐butanesulfonate and trioctylamine dissolved in propylene glycol monomethyl ether acetate. High‐resolution feature sizes as small as 23.1 nm with extremely low line edge roughness (less than 2 nm), high sensitivity (less than 20 mJ cm?2), and good high aspect ratio patterns are obtained by using EUV lithography.  相似文献   

12.
A method for the chemical recycling of poly(carbonate) (PC) plastic wastes in the forms of bisphenol A (BPA) and 1,3-dimethyl-2-imidazolidinone (DMI) was investigated. Treatment with N,N′-dimethyl-1,2-diaminoethane (DMDAE) of PC pellets or PC wastes, derived from compact discs, in dioxane with/without a catalytic amount of base (e.g. Na2CO3 0.5 mol%) for a short period at 100 °C produced DMI and BPA, both in nearly quantitative yields. The aminolysis reaction can be carried out also in DMI, thus saving the use of conventional solvents. A sequential profile of this reaction was verified by examining two model reactions of diphenyl carbonate with N-methylbutylamine and DMDAE, respectively, both proceeded through low-activation energy processes.  相似文献   

13.
Two multimethacrylates having three methacrylate groups (BPA‐3M) and four methacrylate groups (BPA‐4M) have been prepared by reacting hydroxyl groups of 2,2‐bis[4‐(2′‐hydroxy‐3′‐methacryloyloxypropoxy)phenyl]propane (Bis‐GMA) with methacryloyl chloride. BPA‐3M and BPA‐4M have much lower viscosities than the starting Bis‐GMA, because they have only one or no hydroxyl group. Photopolymerizations of the multifunctional methacrylates were conducted by exposure to visible light using camphorquinone and 2‐(N,N‐dimethylamino)ethyl methacrylate as a photoinitiating system. High conversions >50% resulted from photopolymerization of BPA‐3M, whereas Bis‐GMA showed lower conversions under the same condition, implying better mechanical properties for the composite resins made from BPA‐3M. BPA‐4M showed much lower conversions in the photopolymerization condition. Water sorption of the photocured composite of BPA‐3M containing 50 wt % of inorganic fillers was found to be 0.15%, which is only one‐tenth of the commercial Bis‐GMA composite. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 2033–2037, 1999  相似文献   

14.
Six new poly(amide‐imide)s 8a–f containing trimethylene moiety in the main chain were synthesized by the polycondensation reactions of 1,3‐bis[4,4'‐(trimellitimido) phenoxy] propane 6 with six different aromatic diamines 7a–f in a medium constituting N‐methyl‐2‐pyrrolidone, triphenylphosphite, CaCl2, and pyridine as condensing agents. The polycondensation reaction produced a series of novel poly(amide‐imide)s 8a–f in high yields with inherent viscosities between 0.35 and 0.63 dL/g. The resulting poly(amide‐imide)s were characterized by elemental analysis, viscosity measurements, thermal gravimetric analysis (TGA and DTG), solubility tests, and FTIR spectroscopy. 1,3‐Bis[4,4'‐(trimellitimido) phenoxy] propane 6 as a new monomer containing trimethylene moiety was synthesized using a three‐step reaction. At first 1,3‐bis[4,4'‐nitrophenoxy] propane 3 was prepared by the reaction of 4‐nitrophenol 1 with 1,3‐dibromo propane 2 in DMF solution . Then, dinitro 3 was reduced to 1,3‐bis[4,4'‐aminophenoxy] propane 4 by using a solution of sodium sulfite in ethanol. Finally, 1,3‐bis[4,4'‐(trimellitimido) phenoxy] propane 6 was prepared by the reaction of one equivalent diamine 4 with two equivalents of trimellitic anhydride 5 in a mixture of acetic acid‐pyridine (3 : 2). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

15.
A novel and efficient formation of 2‐iminobenzo‐1,3‐oxathioles from readily available precursors via a copper(I)‐catalyzed one‐pot cascade process has been developed. Various 2‐iminobenzo‐1,3‐oxathioles, which might be useful in pharmaceutical and biochemical areas, were conveniently synthesized in good to excellent yields.  相似文献   

16.
Hybrid solid polymer electrolyte films consisting of poly(vinyl alcohol) (PVA), poly(methyl methacrylate) (PMMA), LiBF4, and ethylene carbonate/propylene carbonate (EC/PC) were prepared with a solvent‐casting technique. The complexation was investigated with Fourier transform infrared and X‐ray diffraction. The ionic conductivities of the electrolyte films were determined with an alternating‐current impedance technique for various temperatures in the range of 302–373 K. The maximum conductivity value, 1.2886 × 10?3 S/cm, was observed for a PVA–PMMA–LiBF4–EC complex. Thermogravimetry/differential thermal analysis was performed to ascertain the thermal stability of the electrolyte with the maximum conductivity value. For an examination of the cyclic and reversible performance of the film, a cyclic voltammetry study was carried out. The surface morphology of the EC‐and PC‐based electrolytes was examined with scanning electron microscopy. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2794–2800, 2003  相似文献   

17.
Three adamantane derivatives substituted by epoxy groups, 1,3‐bis(glycidyloxy)adamantane ( 2a ), 5,7‐dimethyl‐1,3‐bis(glycidyloxy)adamantane ( 2b ), 1,3,5‐tris(glycidyloxy)adamantane ( 2c ), were synthesized from the corresponding adamantanediol or triol in good yields. These three epoxy compounds were polymerized with an acid anhydride, and the heat resistance of the resulting resins was evaluated. The resin prepared from 2c exhibited high heat resistance with the glass transition temperature (Tg) of 208°C and low degree of coloring by heating. The epoxy compounds were also found to be potentially useful as the precursors of high heat‐resistant resins by thermal homopolymerization. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

18.
To improve the solubility in organic solvent of chitosan, o‐benzoylchitosan was synthesized by acylation with benzoyl chloride and then used in the reaction with 2‐chloro‐1,3,2‐dioxaphosphospholane (COP) to prepare phosphorylcholine‐terminated o‐benzoylchitosan (PC‐BCS). PC‐BCS had a structure with a phospholipid polar group characterized by FTIR and 1H NMR. PC‐BCS had been polysubstituted by a PC group, which made PC‐BCS viscous liquid. The anticoagulant properties of PC‐BCS were evaluated by means of blood‐clotting and platelet adhesion assay. The blood‐clotting assay indicated that PC‐BCS could prolong the blood‐clotting process. Platelet adhesion assay showed that PC‐BCS could effectively inhibit the platelet adhesion and activation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 489–493, 2003  相似文献   

19.
The synthesis and characterization of a fully aliphatic polymeric azide by polymerization of its vinyl monomer 1,3‐diazidoisopropyl methacrylate (DAIPM) is reported. DAIPM was prepared by azidation of epichlorohydrin followed by coupling with methacrylic acid. Homopolymer and copolymers with methyl methacrylate were prepared and characterized by IR, GPC, TGA, DTA, and elemental analyses. These polymers are freely soluble in organic solvents like dichloromethane, tetrahydrofuran, dimethyl formamide, acetone, and so forth and do not crosslink on storing. The polymers show decreased thermal stability with an increase in azide content and undergo exothermic decomposition on heating. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1852–1857, 2003  相似文献   

20.
A facile and green synthesis of six‐membered cyclic carbonates, the potential monomers for isocyanate‐free polyurethanes and polycarbonates, was achieved by transesterification of diols with dimethyl carbonate catalyzed by immobilized Candida antarctica lipase B, Novozym®435, followed by thermal cyclization in a solvent‐free medium. The difference in the chemospecificity of the lipase for the primary, secondary and tertiary alcohols as acyl acceptors was utilized to obtain a highly chemoselective synthesis of the cyclic carbonate in high yield. In the lipase‐catalyzed reaction with diols, the product contained almost equal proportions of mono‐ and di‐carbonates with 1,3‐propanediol having two primary alcohols, a higher proportion of mono‐carbonate with 1,3‐butanediol having a primary and a secondary alcohol, and mainly mono‐carbonate with 3‐methyl‐1,3‐butanediol having a primary and a tertiary alcohol. The chemospecificity of cyclic carbonates formed by thermal treatment at 90 °C was closely related to the proportion of mono‐carbonate. The yield of cyclic carbonate was 99.3% with 3‐methyl‐1,3‐butanediol, 85.5% with 1,3‐butanediol, and 43.2% with 1,3‐propanediol.  相似文献   

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