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1.
A series of bismaleimides was synthesized from bis(4‐amino‐3, 5‐dimethylphenyl) (X) phenyl methane (X = 3′chloro, 3′‐bromo, 3′‐benzyloxy, 4′‐chloro, 4′‐fluoro) and maleic anhydride. The bismaleimides were subsequently polymerized with various diamines by Michael addition to yield novel polyaspartimides. All the polymers exhibited good solubility in organic solvents and the inherent viscosity of the polymers were in the range of 0.40–0.56 dL/g, which is good enough to fabricate composites and films. The temperature at which 10% weight loss occurred was in the range of 390–441°C. The polymers had high glass transition temperature in the range of 205–275°C and left about 31.95–84.20% char yield at 800°C indicating that they have good self‐extinguishing property. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

2.
Two new ester‐type monomers were synthesized by the condensation of acrylic acid with the products of the hydroxyethylation of 4‐nonylphenol or 4‐tert‐butylphenol. The hydroxyethylation reaction was performed with 1,3‐dioxolan‐2‐ona in the presence of alkalies. By hydroxyethylation, the phenols were changed into alcoholic derivatives able to react with acrylic acid to give acrylic esters. The insertion of the aryl–alkyl groups into the structure of the acrylic esters, and implicitly of the corresponding polymers, was carried out with the intention of increasing their thermostability and improving their behavior as pressure‐sensitive adhesives on the whole. The monomers and the polymers were characterized by elemental and thermogravimetric analyses, IR and 1H‐NMR spectroscopy, and other special methods. The results of these investigations confirmed the formulated suppositions. The inherent viscosities of the resulting polymers were in the range of 47–64 mL/g, and their thermal stability was up to 315–320°C, far higher than that of the polyacrylates used. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 802–814, 2002  相似文献   

3.
Metal salts of mono(hydroxypentyl)phthalate [M(HPP)2, where M is Ca2+, Cd2+, Pb2+, or Zn2+] were synthesized by the reaction of 1,5‐pentane diol, phthalic anhydride, and metal acetate. A new series of metal‐containing polyurethanes containing ionic links in the main chain were synthesized by the reaction of hexamethylene diisocyanate or toluylene 2,4‐diisocyanate with the M(HPP)2 salts. The structures of the monomers and polymers were confirmed with infrared, 1H‐NMR, and 13C‐NMR spectra and elemental analysis. The polymers were also characterized with thermogravimetric analysis, differential scanning calorimetry, and solubility and viscosity measurements. The antibacterial activity of these polyurethanes was investigated with the agar diffusion method. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1194–1206, 2002  相似文献   

4.
A series of five new conjugated polythiophene (PT) derivatives containing piperidinyl groups as a side chain were synthesized by ferric trichloride oxidization. All of the polymers were soluble in common organic solvents, and their high regioregularity were confirmed by 1H‐NMR. The weight‐average molar masses ranged from 5931 to 22,955 g/mol with a low polydispersity index ranging from 1.18 to 1.79. The fluorescence emission maximum of poly[3‐(N‐methyl propionate–4′‐piperidine)methylene–thiophene] in the films was 725 nm in the yellow–red region, higher than that of the other PT derivatives. All five polymers exhibited reversible p‐doping/dedoping (oxidation/reneutralization) processes; this indicated that these polymers could be applied in electrical equipment in the doping state. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

5.
Brominated bismaleimides were prepared by reacting 3(4)‐maleimidobenzoylchloride with various bisphenols, using chloroform as solvent and triethylamine as acid acceptor. These monomers were characterized by elemental analysis, infrared (IR), and proton nuclear resonance (1H‐NMR) spectroscopy. Thermal properties of monomers were accomplished by differential scanning calorimetry (DSC) and dynamic thermogravimetric analysis (ATG). The properties of these compounds were compared with those of monomers derived from bisphenol A and bisphenol A chlorinated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3881–3885, 2006  相似文献   

6.
Several polymers were evaluated as candidates for the production of high‐performance microcellular closed‐cell foams. The polymers involved were a polysulfone, a polyethersulfone, a polyphenylsulfone, a polyetherimide, and a poly(ether ketone ketone), and their suitability was gauged by measuring rates at which they could be impregnated with carbon dioxide under pressure at room temperature. This step is essential to the subsequent step of heating the impregnated samples at various temperatures to create foamed structures. The present study focused primarily on the use of the polysulfone in this regard. Microcellular foams of this polymer were found to have average cell sizes in the range 1–10 μm and cell densities on the order of 1010–1014 cells/cm3. The microstructures of these foamed samples were controlled through careful choices of the foaming temperature and the foaming speed to produce a wide range of foam densities. Since these materials were prepared for possible use as structural materials, tensile tests were conducted to investigate the dependence of some of their mechanical properties on the foam densities (relative to those of the unfoamed polymer). The results indicated that the tensile moduli of these polysulfone foams increased with the square of their relative densities, and the tensile strengths were proportional to these densities. Both of these experimental findings are in agreement with theory. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1692–1701, 2002  相似文献   

7.
Two series of heterocyclic aromatic polymers were synthesized from 4,4′‐(4,4′‐isopropylidenediphenoxy)bis(phthaltic anhydride) and 2,2′‐bis(3,4‐dicarboxyphenyl)hexafluoropropane dianhydride by two‐step method. The inherent viscosities were in the range of 24–45 cm3/g. The effects of the rigid benzoxazole group in the backbone of copolymer on the thermal, mechanical, and physical properties were investigated. These polymers exhibit good thermal stability. The temperatures of 5% weight loss (T5) of these polymers are in the range of 403–530°C in air and 425–539°C in nitrogen. The chard yields of these polymers are in the range of 15–24% in air and 54–61% in nitrogen. These polymers also have high glass‐transition temperatures and a low coefficient of thermal expansion and good mechanical properties. The poly(benzoxazol imide) has a higher tensile strength and modulus than those of neat polyimide. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

8.
Phosphorylation of poly(epichlorohydrin) (PECH) was successfully performed via reacting the P? H bond of 9,10‐dihydro‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) with the pendent chloromethyl groups of PECH. From this reaction, phosphorus‐containing PECH with hydroxyl terminal groups was obtained. This compound was further reacted with toluene‐2,4‐diisocyanate to form a phosphorous‐containing polyurethane. The performance of the phosphorylation reaction and the structure of the resulting polymers were characterized by Fourier transform infrared spectroscopy, phosphorous‐31 nuclear magnetic resonance (31P NMR) spectroscopy, and elemental analysis. The phosphorylated PECH and polyurethane were characterized by thermogravimetric analysis (TGA), which showed weight loss retardation behavior under air at high temperature at >500 °C and high char yield at 700 °C. Both of the synthesized polymers are potentially useful as multifunctional modifiers for epoxy resins and for improving the toughness and flame retardancy of the resins. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2254–2259, 2002  相似文献   

9.
A series of copolymers were prepared by the reaction of various bisphenols with a 50:50 molar ratio of two bisfluoro compounds, 4,4′‐bis(1‐fluoro‐2‐trifluoromethyl benzyl) benzene and 4,4′‐difluorobenzophenone. The synthesized polymers were well characterized for their thermal, mechanical, and electrical performances. The copolymers showed a better set of properties than their analogous homopolymers derived from 4,4′‐bis(1‐fluoro‐2‐trifluoromethyl benzyl) benzene and bisphenols. The microstructures of the copolymers were analyzed by 1H‐, 13C‐, 19F‐, distortionless enhancement by polarization transfer 90, two‐dimensional 1H–1H homonuclear correlation spectroscopy, and 13C–1H correlation spectroscopy NMR techniques. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1292–1305, 2005  相似文献   

10.
Poly(ester-urethane-imide)s were prepared by Diels–Alder polyaddition of 1,6-hexamethylene-bis(2-furanylmethylcarbamate) with various bismaleimides containing ester groups in the backbone. The Diels–Alder reaction was carried out in m-cresol, at 110°C, followed by thermal and chemical aromatization of tetrahydrophthalimide intermediates. The monomers and polymers were characterized by IR, 1H-NMR spectroscopy and elemental analysis. Thermal properties of the polymers were investigated by differential scanning calorimetry and dynamic thermogravimetric analysis.  相似文献   

11.
Eight poly(phosphate ester)s comprising five homopolymers (polymers I–V), two copolymers (polymers VI and VII), and one terpolymer (polymer VIII) were synthesized by interfacial polycondensation of phenyl phosphorodichloridate with various bisphenols. The polymers were characterized by spectroscopic techniques. The copolymer and terpolymer ratios were determined by 1H‐NMR spectroscopy. The molecular weights of the polymers were determined by end‐group analysis using 31P‐NMR spectroscopy. Accelerated hydrolytic degradation studies under alkali‐catalyzed conditions showed that the polymer from biphenol (polymer IV) is the most stable and the polymer from thiodiphenol (polymer V) is the least stable. The products of hydrolytic degradation were analyzed and a suitable mechanism for the degradation of the polymers proposed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 626–631, 2003  相似文献   

12.
Cured networks of epoxy–imide resin cured with four types of phosphorylated diamine curing agents that contained different alkyl groups on phosphorus were studied. The structures of these novel phosphorus‐containing curing agents were confirmed by Mass, EA, IR, and 1H‐NMR and 13C‐NMR spectra characterization. The reactivities were measured by differential scanning calorimetry (DSC). It is found that the reactivities were not affected by the types of alkyl groups in the curing agents. In thermal gravimetric analysis (TGA), those polymers that were obtained through the curing reactions between epoxy–imide resin and four curing agents (BAMP, BAEP, BAPP, and BABP) also demonstrated excellent thermal properties as well as a high char yield. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 141–147, 2002  相似文献   

13.
A series of bismaleimide monomers with amide groups were prepared and characterized. Structurally different bismaleimides (with amide units) were synthesized by a reaction between 4‐maleimidobenzoyl chloride and various diamines. The monomers were characterized by infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and elemental analysis. The thermal characterization of the bismaleimides was accomplished with differential scanning calorimetry and dynamic thermogravimetric analysis. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 567–572, 2006  相似文献   

14.
Three novel bithiazole‐containing polymers were synthesized from 2,2′‐diamino‐4, 4′‐bithiazole (DABT) condensed with bismaleimide, bis(methyloxycarbonyl ethyl)tin dichloride (BETD), and 4,4′‐diphenylmethane diisocyanate (DPDI), respectively. A new series of polymeric complexes were prepared from Fe2+ and the three polymers. These polymers and their complexes were characterized through FTIR, 1H‐NMR, and related techniques. The chemical compositions of the complexes were determined by XPS. The presence of the exchange interaction between the unpaired electrons was investigated by ESR spectroscopy. The magnetic behavior of these complexes was measured as a function of the magnetic field strength (0–40 kOe) at 5 K and as a function of temperature (5–300 K) at a magnetic field strength of 30 kOe. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1353–1359, 2001  相似文献   

15.
This article concerns the in situ compatibilization of immiscible isotatic polypropylene/styrene–butadiene–styrene triblock copolymer blends (i‐PP/SBS) by use of a reactive mixture. For this purpose, maleated PP (PP–MAH) and SBS (SBS–MAH) were used as functionalized polymers and 4,4′‐diaminediphenylmethane was used as a coupling agent between maleated polymers, resulting in a graft copolymer. Binary blends of i‐PP/SBS, nonreactive ternary blends of i‐PP/PP–MAH/SBS, and reactive ternary blends of i‐PP/PP–MAH/SBS–MAH with varying diamine/anhydride molar ratios were prepared. The mechanical properties of the blends were determined by tensile and impact‐resistance tests. The optimum improvement in the mechanical properties was found when the diamine/anhydride molar ratio in the ternary reactive blends was 0.5/1. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 516–522, 2003  相似文献   

16.
Four bismaleimides with mesogen “amide–ester” aromatic and flexible polymethylenic group variable length (8 ≤ n ≤ 11) were synthesized in two stages, producing yields exceeding 80%. These bismaleimides (BMIs) were obtained after several purifications by dissolution—precipitation in dimethylformamide–methanol (1/4) with over 94% purity (high‐performance liquid chromatography). These pure BMIs were characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy, and elemental analysis and studied by differential scanning calorimetry, thermogravimetric analysis, polarized light microscopy, and X‐ray diffraction. Solubilities and thermal properties show effects of parity. The even BMIs are more difficult to solubilize than the odd BMI. The melting points of the even BMI (approximately, 220°C) are far higher than those of odd BMI (approximately, 160°C). Crosslinking temperatures of even BMI are close to 230°C, whereas odd BMI crosslinking temperatures are higher (approximately, 250°C). Even BMIs give rise to a liquid crystal state upon melting. Under the same conditions, odd BMIs give rise to an amorphous state; however, after crosslinking, the four bismaleimides give rise to an ordered liquid crystal state of smectic type. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

17.
A hydrated, 1% by weight Na‐kaolinite suspension in deionized water was prepared, completely characterized, and reproducible measures of flocculation efficiency were validated. Flocculation tests of copolymers of acrylamide (AM) with dimethylacrylamide (DMA), methacrylamide (MeAM), or N‐t‐butylacrylamide (NTBAM) with 1% Na‐kaolinite suspensions gave average settling rate rates which decreased as the proportion of DMA, MeAM, or NTBAM in the copolymer increased. However, for a similar weight‐average molecular weight and slightly lower 〈rg〉, the copolymer from DMA‐co‐AM‐3 gave settling rates and supernatant turbidities comparable to similar types of commercial polymers. This new copolymer was also more resistant to changes in pH or the presence of an electrolyte than were the tested commercial polymers. Cationic derivatives of the new copolymers gave lower average settling rates and higher supernatant turbidities than those of Percol 721 (cationic PAM), probably because of their lower charge densities. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2090–2108, 2002; DOI 10.1002/app.10562  相似文献   

18.
Polyaniline (PAN), poly(o‐bromoaniline) (POBA), and poly(aniline‐co‐o‐bromoaniline) (PABA) were synthesized by oxidative coupling. These polymers are protonated by 10–20% methane sulfonic acid (MSA) and 1M HCl. The new polymer bases have greater solubility than that of PAN in common polar organic solvents; PAN–MSA was observed to be the most thermally stable of these polymers. POBA is associated with residual quinoid diimine units as illustrated in the IR and UV‐vis spectra, after reduction with hydrazine dihydrochloride. Both the doping agents cause a downward shift of the quinoid absorption in the IR spectra. MSA‐ and HCl‐doped PAN and PABA polymers exhibit a coil‐like conformation in DMSO, whereas only MSA‐doped PAN and PABA show an “expanded coil‐like” conformation in m‐cresol with a “free carrier tail” above 800 nm in their electronic spectra. XPS spectra indicated the presence of covalent bromine in the POBA and PABA polymers. Bromine retention was greater in the homopolymer as evidenced by the IR studies after aging at 350°C. Compared to HCl, MSA is found to be a more effective dopant, enhancing the conductivity of the copolymers by 102–103 times in magnitude. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2662–2669, 2002  相似文献   

19.
Experimental results at 25°C are reported for infinite‐dilution distribution coefficients for 19 nonvolatile solutes between aqueous solution and three kinds of polymer films, and for their diffusion coefficients in the polymer matrix. The experiments were performed by coupling UV spectroscopy and gravimetric measurements with mass balances. The solutes are aromatic nonvolatile compounds that are of interest in environmental technology and may serve as model compounds for drug‐delivery systems. The polymers are ethylene‐vinyl acetate copolymers with 33 (EVAc33) and 45 (EVAc45) weight percentage vinyl acetate, and poly(vinyl acetate) (PVAc) widely used in drug‐delivery devices. For PVAc, a long time is required to reach equilibrium. Because the required time is too long for reasonable experimental studies, equilibrium distribution coefficients were calculated from finite‐time data by using a diffusion model. The contribution of surface adsorption is shown to be negligible. Infinite‐dilution distribution coefficients Ks, defined as the volume fraction of solute in the polymer divided by that in water, tend to increase with vinyl acetate content; they range from near unity to several hundred. Diffusion coefficients, determined from time‐dependent sorption data, are significantly larger in EVAc copolymers (10?10 to 10?8 cm2/s) than in PVAc (10?12 cm2/s). These data may be useful for design of membrane processes, for controlled delivery of drugs, and for application in packaging and storage of food, chemicals, and pharmaceuticals. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2041–2052, 2002  相似文献   

20.
A novel class of bismaleimides and bisnadimides containing amide linkages in their backbones were synthesized and characterized. The synthesis of these polymer precursors was carried out by reacting a diamine containing amide linkages with maleic/nadic anhydride. They were alternatively prepared by reacting the monomaleamic/monoadiamic acid of an aromatic diamine (1 mol) with terephthaloyl chloride (0.5 mol) and subsequent cyclodehydration. The latter new preparation method circumvented the hydrogeneration necessary in the first method of synthesis. The monomers were characterized by infrared (IR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. Differential thermal analysis (DTA) of monomers showed that bisnadimide and bismethylnadimide were polymerized at lower temperatures than the corresponding bismaleimide. Thermogravimetric analysis (TGA) in nitrogen and air atmosphere revealed that all polymers were stable up to 321–363°C. Their char yield at 800°C under anaerobic conditions was 49–67%.  相似文献   

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