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1.
Modification of plasma-polymers prepared from phenylsilane with sulfur trioxide was investigated by FT/IR spectroscopy and ESCA. The sulfonation of phenyl groups in the plasma-polymers occurred rapidly within 1 min when exposed to SO3 gas. The S/C and O/C atomic ratios determined by ESCA for the modified polymers were 0.138 and 0.418, respectively. The sulfonation made the plasma-polymers electrically conductive. The conductivity was sensitive to moist atmosphere. The logarithm of the impedance at 120 Hz decreased linearly with increasing the relative humidity. The plasma-films containing sulfonate groups may be a new material for moisture sensor devices.  相似文献   

2.
To overcome the use of halogenated compounds, which are usually incorporated in plastics as flame retardant additives, the authors investigated the synthesis possibilities, to introduce with covalent bonds, the flame retarder groups at different positions of the polymer chains. They established correlations between the topology of the phosphonated groups and the flame retardant properties. They attempt to determine the origin of the flame resistance obtained in several cases. Their goal is to extend their interesting results obtained from oligomers, to polymer of high molecular weight.  相似文献   

3.
Copolymers of 4-tert-butoxycarbonyloxystyrene (BOS) and 9-fluorenilideneimino p-styrenesulfonate (FISS) were synthesized. FISS units in copolymers became p-styrenesulfonic acid units upon ultraviolet irradiation. The irradiated copolymers thermally decomposed to poly(hydroxystyrene) by liberating tert-butoxycarbonyl (BOC) units at temperatures where the unirradiated copolymers were stable. The thermal decomposition of the copolymers catalyzed by sulfonic acid formed photochemically was studied by thermogravimetry. The pseudo first-order rate constant (k) and the activation energy for the acid catalyzed thermal decomposition of BOC units in copolymers were evaluated. The thermolysis of the irradiated copolymer system was compared with that of the irradiated blended system of poly(4-tert-butoxycarbonyloxystyrene) (PBOCST) and 9-fluorenilideneimino p-toluene-sulfonate (FITS). © 1993 John Wiley & Sons, Inc.  相似文献   

4.
Summary The synthesis of sarcosylglycolylglycine and L-prolylglycolylglycine was carried out.  相似文献   

5.
Copolyamides of PA 66/6 lithium 5‐sulfoisophthalic acid (LiSIPA) containing up to 40 mol % of LiSIPA were prepared in a 1L‐pilot reactor operating at high pressures and high temperatures. Interestingly, the presence of lithium sulfonate moieties highly impacted the glass transition temperature of the polyamide. The Tg increased from 59 °C for PA 66 to 155 °C for a copolymer containing about 40 mol % of LiSIPA. 1,3‐Dihexylbenzenedicarboxamide and lithium p‐toluenesulfonate were synthesized as model compounds to investigate the interaction of lithium sulfonate moieties and amide functions. Infrared spectroscopy using ATR technology performed on mixture of both compounds showed that the carbonyl group of amide functions interacts with the lithium cation of lithium sulfonate moieties. Similar S? O and C? O adsorption bands were observed in copolyamides PA 66/6LiSIPA and in mixture of model compounds, which strongly suggest the formation in the copolyamides of physical cross‐linking points centered on lithium cations coordinated by carbonyl groups of amide functions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

6.
Poly(p‐divinylene phenylene) derivatives bearing fluorene and carbazole units in the main chain and 5‐phenyl‐1,3,4‐oxadiazole moieties as side groups were prepared by the polycondensation of a newly synthesized monomer, [2‐(5′‐phenyl‐1′,3′,4′‐oxadiazole‐2′‐yl)‐1,4‐xylylene]bis(triphenyl phosphonium bromide) (OXAD), with 9,9‐dibutylfluorene‐2,2′‐dicarbaldehyde (DBFDA) and 9‐(2‐ethylhexyl)carbazole‐3,6‐dicarbaldehyde (EHCDA), which gave DBFDA–OXAD and EHCDA–OXAD. Analogues of these polymers without the side groups were also synthesized by the reaction of 1,4‐xylene bis(triphenyl phosphonium bromide) (PXYL) with the dicarbaldehydes, which gave DBFDA–PXYL and EHCDA–PXYL. All the synthesized polymers are soluble in organic solvents, giving films of good quality. The polymers are stable beyond 375 °C. They emit blue and blue‐green light, and their quantum yields are 38–79% in solution and 1–24% in film, depending on the fluorene and carbazole units as well as the side groups. In particular, the OXAD‐based polymers contain hole‐facilitating backbones and electron‐facilitating side groups, perhaps allowing these polymers to transport both holes and electrons. Overall, the synthesized polymers are potential candidates for the fabrication of light‐emitting devices. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1173–1183, 2002  相似文献   

7.
8.
The synthesis of various phosphoranimines including (CH3OCH2CH2O) (CF3CH2O)2P?N? Si(CH3)3, (CH3OCH2CH2OCH2CH2O) (CF3CH2O)2P?N? Si (CH3)3, (CH3OCH2CH2O)2(CF3CH2O) P?N? Si(CH3)3, and (CH3OCH2CH2OCH2CH2O)(CF3CH2O) P?N? Si(CH3)3 via the Staudinger reaction of (CH3)3SiN3 with the suitably substituted phosphite is reported. These monomers were polymerized using tetra-n-butylammonium fluoride and N-methylimidazole in various solvents at several temperatures. In situ 31P-NMR kinetic studies and Mn versus time studies were also performed for the monomers to understand the propagation mechanism. © 1994 John Wiley & Sons, Inc.  相似文献   

9.
The synthesis of a series of monomers containing isopropenylphenoxy groups was carried out. On irradiation with UV light in the presence of onium salt photoacid generators, these monomers undergo a chain extension reaction consisting of a dimerization followed by a Friedel-Crafts ring closure which results in the formation of polymers with indane groups in the backbone. Aryl imide-containing monomers bearing isopropenylphenoxy groups were also shown to undergo facile photoinduced cationic polymerization. The resulting polymers displayed excellent thermal stability. © 1995 John Wiley & Sons, Inc.  相似文献   

10.
Oligo(oxyethylene) macromonomers bearing sodium sulfonate group have been synthesized through four reactions: (1) ring-opening polymerization of oxirane, (2) etherification of monomethoxyl oligo(oxyethylene) and epichlorohydrin, (3) sulfonation of cycloxyl compound, and (4) end-capping of sodium oligo(oxyethylene) sulfonate by methacrylic group. A desired length of oligo(oxyethylene) in the macromonomers can easily be achieved by controlling the ratio of reactants in the ring-opening step. The structures of the products of each reaction were identified by IR, 1H-NMR, and GPC. Polymers of the monomers were also characterized by GPC and DSC. © 1993 John Wiley & Sons, Inc.  相似文献   

11.
Shape memory polymers (SMP) can be deformed to a stable, temporary shape and recovered to their original shape by applying a stimulus. These networks rely on the presence of two types of net points to establish their permanent and temporary shapes. Classical strategies to stabilize temporary shapes rely on cooling below Tg/Tm where macromolecules become pinned in a stressed state. Recovery of the SMP usually involves heating to above the transition temperature where the permanent shape is remembered. Employing reversible binding groups (RBGs) in SMPs has emerged as an alternative strategy for stabilizing temporary shapes or imparting recyclability of the permanent shape. The use of dynamic chemistry often engenders additional functionality such as intrinsic self-healing characteristics or alternative shape recovery triggering strategies. SMPs bearing both supramolecular and covalent RBGs will be reviewed with an emphasis on hydrogen bonding, ionic interactions, metal–ligand coordination, and dynamic covalent exchange and addition reactions. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1340–1364  相似文献   

12.
Vinyl monomers bearing N-substituted phenoxazine or 2,8-dimethylphenoxazine units were synthesized starting with the corresponding phenoxazines. N-substituents were 2-vinylbenzyl-oxycarbonylethyl group prepared via 2-carboxyethyl group, 3-methacrylamido-, 3-acrylamido-, or 3-(4-styrenesulfonamido)-propyl group prepared via 3-aminopropyl group, vinylbenzyl, or 2-vinyloxyethyl group attached by the displacements of sodium salts of the phenoxazines to the chlorides, and 2-methacryloyl- or 2-acryloyl-oxyethyl group prepared via 2-hydroxyethyl group. Free-radical polymerixations of these novel monomers proceeded smoothly, except those with 2-vinyloxyethyl group, which were susceptible to BF3-etherate. Changes of the visible absorption spectrum of iodine in THF with addition of the monomers and polymers were considerable, with the appearance of new absorption peaks or shoulders in major cases.  相似文献   

13.
We report the design, synthesis and characterization of new benzothiadiazole- and pyrrole-based copolymers whose solubility and bandgap drastically change after thermal treatment of their thin films.  相似文献   

14.
The synthesis of various vinylbis(silanes) from some aryl and heteroaryl aldehydes and (Me3Si)3CLi in Et2O is described. Friedel-Crafts reaction of 1,1-bis(trimethylsilyl)-2-(2-naphthyl)ethene with various acyl chlorides (RCOCl, R = Me, Et, i-Pr, i-Bu, n-pent) gave the corresponding α-silyl-α,β-unsaturated enones with high E steroselectivity. Moreover, poly(styrene)-co-[2,2-bis(trimethylsilyl)ethenyl(styrene)] obtained via the reaction of polymers bearing pendant enone functions and (Me3Si)3CLi, reacts with the same acyl chlorides in the presence of catalytic amount of AlCl3 to give the new macromolecules bearing α-silyl-α,β-unsaturated enones and α,β-unsaturated enones.  相似文献   

15.
Hydrogen-bonding triarylamines, 4-(N,N-bis(4-methoxyphenyl)amino)benzoic acid (TPA1), 5-(N,N-bis(4-methoxyphenyl)amino)isophthalic acid (TPA2), and N-(4-(1H-benzimidazol-2-yl)phenyl)-N,N-bis(4-methoxyphenyl)amine (BImTPA), were synthesized as radical cation precursors. TPA1 and TPA2 are readily p-doped by AgSbF(6) to give highly persistent radical cations. Poor solid-state spin yields of the radical cation from BImTPA may be due to spin delocalization.  相似文献   

16.
Some new photorefractive polymers containing indole groups were synthesized and characterized by IR, 1H NMR, and UV techniques. The Gibbs free energy changes (ΔG) of corresponding reactions were predicted by density functional theory to be 4.19 and ?9.71 kcal mol?1 for –H, and 4.12 and ?11.93 kcal mol?1 for –OCH3, respectively. The glass transition temperature (T g) of the polymers were about 96–111 °C. The nonlinear second-order optical susceptibility was predicted to be 2.84 × 10?30 and 1.04 × 10?30 esu by theoretical quantum calculations.  相似文献   

17.
Two spirooxazine (SO) compounds containing bromobutyl substituents on 1-position (SO1) and 9′- position (SO2) have been synthesized and characterized by 1H-NMR, IR and ESI-MS in this paper. SO1-g-PMMA and SO2-g-PMMA polymer were prepared by grafting SO1 and SO2 onto PMMA through C-Br bonding sites. Also, SOs were doped into PMMA matrix to afford SO1-d-PMMA and SO2-d-PMMA. Photochromic behaviors of these compounds have been studied. Compared with SO1, SO2 exhibited better photoresponse and slower bleaching in dichloromethane solution. Inserted into polymer films, the decoloration process of SOs were significantly retarded and it was found that the fading curves fitted a first-order equation; As regard to four polymers, 1-position grafting (SO2-g-PMMA) can cause a higher reduction degree on the thermal fading rate.  相似文献   

18.
19.
The present paper focuses on (i) a new synthetic methodology to prepare vinyl ether-based synthetic glycoconjugates (glycopolymers) with well-controlled structure, and on (ii) the application of glycopolymers bearing modified disaccharide residue as thermotropic liquid crystalline (LC) materials. Two vinyl ethers (VEs) having pendant glucose residues with their hydroxyl functions protected by acetyl and isopropylidene groups, respectively, were found to undergo living cationic polymerization initiated by a HI/ZnI2-initiating system. Deprotection of the resultant monodisperse polymers led to water-soluble polymers bearing a pendant glucose residue. Sequential living block copolymerization of glucose-containing VE and alkyl VE, and subsequent deprotection afforded an amphiphilic block copolymer of well-controlled structure. Transmission electron microscopic observation of its cast thin film revealed microphase-separated surface morphologies that varied with varying segment composition ratio. A VE substituted with a heptadecanoated cellobiose pendant was independently prepared, and was cationically polymerized to give a thermotropic LC polymer. From X-ray analysis, the mesophase was assigned to a discotic columnar in type, in which each main chain, extended due to the steric repulsion between the neighboring bulky pendants, was surrounded by three discotic columns.  相似文献   

20.
Novel phenolic novolac resins, bearing maleimide groups and capable of undergoing curing principally through the addition polymerization of these groups, were synthesized by the polymerization of a mixture of phenol and N‐(4‐hydroxy phenyl)maleimide (HPM) with formaldehyde in the presence of an acid catalyst. The polymerization conditions were optimized to get gel‐free resins. The resins were characterized by chemical, spectral, and thermal analyses. Differential scanning calorimetry and dynamic mechanical analysis revealed an unexpected two‐stage curing for these systems. Although the cure at around 275°C was attributable to the addition polymerization reaction of the maleimide groups, the exotherm at around 150 to 170°C was ascribed to the condensation reaction of the methylol groups formed in minor quantities on the phenyl ring of HPM. Polymerization studies of non‐hydroxy‐functional N‐phenyl maleimides revealed that the phenyl groups of these molecules were activated toward an electrophilic substitution reaction by the protonated methylol intermediates formed by the acid‐catalyzed reaction of phenol and formaldehyde. On a comparative scale, HPM was less reactive than phenol toward formaldehyde. The presence of the phenolic group on N‐phenyl maleimide was not needed for its copolymerization with phenol and formaldehyde. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 641–652, 2000  相似文献   

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