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1.
A new substituted diphenylamine diazonium salt, N‐methyl‐2‐nitrodiphenylamine‐4‐diazonium salt (MNDDS) and its diazoresin (MNDDS‐resin) were synthesized and their thermostability as well as photosensitivity were investigated. The results show that MNDDS and resin exhibit much higher thermostability than that of the parent compound, diphenylamine‐4‐diazonium salt (DDS) and resin (DDS resin) in solid state or in coating but the photosensitivities of them are confirmed to be in same level. The excellent thermostability of MNDDS and its diazoresin is very important because the storage life of a negative presensitized plate is mainly dependent on it. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 189–193, 1999  相似文献   

2.
3-Methoxydiphenylamine-4-diazonium salt (MDDS) and its diazoresin were synthesized. The photo- and thermal decomposition of salt and the resins were investigated. The results show that MDDS exhibits excellent thermostability as well as high photosensitivity. A series of diazoresins with different organic counteranions, which dissolve in common solvents and usually were chosen to manufacture the negative presensitized plate, were also synthesized The kinetics of the photo- and thermal decomposition of MDDS in ethanol is reported. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1975–1982, 1998  相似文献   

3.
唐有根  蒋金芝 《化学试剂》1999,21(1):15-16,41
以2-甲基-4-硝基苯胺为起始原料,合成了一种新的重氮光敏试剂3-甲基-4-吗啉基苯基重氮四氯化锡复盐,通过UV,IR,^1HNMR和元素分析等手段对标题化合物及两个中间产物进行了结构表征。  相似文献   

4.
2-Sulphonic diphenylamine-4-diazonium salt (SDDS) and its diazoresin were synthesized and their thermal stability and photosensitivity were investigated. The results show that the thermal stability of SDDS is better than that of diphenylamine-4-diazonium salt (DDS), and is close to that of 3-methoxy-diphenylamine-4-diazonium salt (MDDS). The SDDS and its diazoresin are highly susceptible to UV light. The photoimaging behaviour of SDDS-resin was subject to a preliminary study. © 1999 Society of Chemical Industry  相似文献   

5.
In this article, a series of carboxylated acrylate copolymer latices were prepared based on the semicontinuous emulsion polymerization via the pure monomer dropwise manner with three different kinds of carboxylic monomers in presence of reactive emulsifier. The effects of the carboxylic monomers [acrylic acid, methacrylic acid, and monobutyl itaconate (MBI)] on the conversion and the properties of acrylate latices and films have been investigated. The carboxylic groups ( COOH) distribution of these three kinds of latices were investigated as well. The results show that the concentration of surface  COOH (CS) and embedded  COOH (Cb) both increase with the increase of the amount of carboxylic monomers. It shows that MBI, the most hydrophobic of the three carboxylic monomers used, tends to be concentrated inside the particle core, and the latex particles have a narrow size distribution. The results of common stability test have demonstrated that the stability of the latex is satisfactory. Moreover, the water absorption and the acid and alkaline resistance of the latex depend on the kind of carboxylic monomer. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

6.
Polyhedral oligomeric azido‐octaphenylsilsesquioxane (N3‐OPS) was synthesized from octaaminophenylsilsesquioxane (OAPS) via its diazonium salt. The synthesis included nitration of octaphenylsilsesquioxane (OPS) to octanitrophenylsilsesquioxane (ONPS), conversion of ONPS into octaaminophenylsilsesquioxane (OAPS), and conversion of OAPS into N3‐OPS. The kinetics of the conversion of OAPS into N3‐OPS were studied by recording the volume of N2 gas released with the reaction time, which revealed it to be a 1st order reaction. The chemical structures of ONPS, OAPS and N3‐OPS were characterized by 1H‐NMR, GPC, FTIR, 29Si solid NMR, 13C‐NMR, XRD, and elemental analysis. It is proposed that the diazonium salt of OAPS was substituted by the main ? N3 group and a few of the ? OH groups. The ratio of ? N3:? OH was calculated to be approximately 68:32 in N3‐OPS on the basis of the elemental analysis and 1H‐NMR. XRD suggested that N3‐OPS was a kind of amorphous compound. The two‐step conversion mechanism of OAPS to N3‐OPS was briefly discussed. TGA results showed that N3‐OPS was stable at ambient temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

7.
Temperature sensitive random linear and crosslinked copolymers of N‐tert‐butylacrylamide (NTBA) and acrylamide (Am) were synthesized by the solution polymerization method, using regulated dosing of comonomer Am having a higher reactivity ratio (rAm = 1.5) than NTBA (rNTBA = 0.5). Copolymers with varying feed ratios of NTBA and Am (80 : 20 to 20 : 80 mol %) were synthesized and characterized. For the synthesis of copolymer hydrogels, N′, N‐methylene bisacrylamide (MBA) (1.13 mol %) was used along with monomers. The effect of composition on transition properties was evaluated for the linear copolymers and their hydrogels. A definite trend was observed. The incorporation of a higher percentage of the hydrophilic comonomer Am in the structure resulted in the shifting of the transition temperature towards a higher value. The transition temperatures of the copolymers synthesized with feed compositions of 80 : 20, 70 : 30, 60 : 40, 50 : 50, 40 : 60, 30 : 70, and 20 : 80 mol % were found to be 2, 10, 19, 27, 37, 45, and 58°C, respectively. Differential scanning calorimetry (DSC) studies confirmed the formation of random copolymers. The copolymers synthesized with a monomer feed ratio of 50 : 50 with regulated dosing showed a single glass transition temperature (Tg) at 168°C, while the copolymer synthesized with full dosing of Am at the beginning of the reaction showed two Tgs, at 134 and 189°C. The copolymer samples were analyzed by Fourier transform infrared spectroscopy (FTIR) for ascertaining the composition. The composition of the copolymers followed the trend of the feed ratio, but the incorporation of NTBA in the copolymers was found to be lower than the feed ratio because of lower than quantitative yields of the reactions. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 672–680, 2005  相似文献   

8.
On the basis of 2‐hydroxyl‐2‐methyl‐1‐phenylpropanone (HMPP) and poly(ethylene glycol) (PEG), we prepared amphiphilic macrophotoinitiators (HMPP–PEG–HMPP) by first reacting HMPP with isophorone diisocyanate and subsequently reacting it with PEGs with different chain lengths. Fourier transform infrared spectroscopy, high‐performance liquid chromatography, and 1H‐NMR were used to confirm the structure of the amphiphilic macrophotoinitiators. Ultraviolet (UV) absorption spectra showed that the amphiphilic macrophotoinitiators had maximum absorption wavelengths that were similar to those of the low‐molecular‐weight photoinitiator HMPP. The photolysis rate of the amphiphilic macrophotoinitiators was slightly lower than that of HMPP, but the migration rate of the amphiphilic macrophotoinitiators from a UV‐cured matrix was much lower compared to that of HMPP. Because of their amphiphilic nature, these macrophotoinitiators may play roles as both photoinitiators and emulsifiers, and they have been applied to the solution polymerization of water‐soluble monomer acrylamide in water and the emulsion polymerization of methyl methacrylate. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43910.  相似文献   

9.
The use of polymeric reagents simplifies routine azidation of diazonium salts, because it eliminates the traditional purification. An efficient, simple, and effective method for the preparation of aryl azides is described. The synthesis of aromatic azides from the corresponding amines is accomplished under mild conditions with sodium nitrite in the presence of p‐toluenesulfonic acid or concentrated H2SO4 at low temperature (0–5°C to room temperature). The obtained relatively stable diazonium salts, followed by treatment with a polymer‐supported azide ion in water at room temperature to produce the corresponding aryl azides. The spent polymeric reagents can be regenerated and reused for several times without losing their activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

10.
2,6‐Di(4′‐azidobenzylidene)‐methylcyclohexanone (ABC) was one of the most used photoinitiators in negative photoresists industry, rendering insolubility of the resist films at short UV exposure times (several minutes). Although the photodecomposition of aromatic azides is very well established, the peculiarities of the irradiation medium impose specific reaction pathways for arylnitrenes. In this study, photoreactions of arylnitrenes resulted from ABC photolysis were applied in the photoinitiated crosslinking of 1,2‐polybutadiene (1,2‐PB), under soft monochromatic UV irradiation (365 nm). To elucidate the crosslinking mechanism, studies on a model compound were performed. 3‐Methyl‐1‐butene was chosen to simulate the monomeric unit of 1,2‐PB. As a support in photoproducts identifying and with the purpose of a deeper investigation of the ABC photochemistry alone, ABC was photolysed in a rigid matrix of poly(methyl methacrylate). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44694.  相似文献   

11.
A novel, asymmetric diamine, 3‐(4‐aminophenylthio)‐N‐aminophthalimide, was prepared from 3‐chloro‐N‐aminophthalimide and 4‐aminobenzenethiol. The structure of the diamine was determined via IR and 1H‐NMR spectroscopy and elemental analysis. A series of polyimides were synthesized from 3‐(4‐aminophenylthio)‐N‐aminophthalimide and aromatic dianhydrides by a conventional two‐step method in N,N‐dimethylacetamide and by a one‐step method in phenols. These polyimides showed good solubility in 1‐methyl‐2‐pyrrolidinone, m‐cresol, and p‐chlorophenol, except polyimide from pyromellitic dianhydride, which was only soluble in p‐chlorophenol. The 5% weight loss temperatures of these polyimides ranged from 460 to 498°C in air. Dynamic mechanical thermal analysis indicated that the glass‐transition temperatures of the polyimides were in the range 278–395°C. The tensile strengths at break, moduli, and elongations of these polyimides were 146–178 MPa, 1.95–2.58 GPa, and 9.1–13.3%, respectively. Compared with corresponding polyimides from 4,4′‐diamiodiphenyl ether, these polymers showed enhanced solubility and higher glass‐transition temperatures. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

12.
魏东旭  姚晓军  宫红  姜恒 《化学工程师》2012,26(2):16-18,36
以β-巯基乙醇和H2O2溶液为原料合成了羟基乙烷磺酸(ITA),用ITA和CaCO3为原料合成了目标产物羟基乙烷磺酸钙[Ca(HOCH2CH2SO3)2.2H2O],其结构经TGA,FT-IR1,H NMR和元素分析表征。利用热重分析研究了羟基乙烷磺酸钙的热分解过程,在动态空气气氛下,其热分解过程分为两个阶段。第一阶段(30~300℃)失重率为11.06%,失重主要由所含结晶水引起,结晶水的个数为2。第二阶段(300~650℃)失重率为46.16%,这一阶段是其主要分解过程。通过红外光谱确定了羟基乙烷磺酸钙的热分解产物为CaSO4。25℃羟基乙烷磺酸钙在水中的溶解度为120g.100g-1。  相似文献   

13.
Thermal degradation and kinetics of poly(4‐methyl‐1‐pentene) were investigated by nonisothermal high‐resolution thermogravimetry at a variable heating rate. Thermal degradation temperatures are higher, but the maximum degradation rates are lower in nitrogen than in air. The degradation process in nitrogen is quite different from that in air. The average activation energy and frequency factor of the first stage of thermal degradation for the poly(4‐methyl‐1‐pentene) are 2.4 and 2.8 times greater in air than those in nitrogen, respectively. Poly(4‐methyl‐1‐pentene) exhibits almost the same decomposition order of 2.0 and char yield of 14.3–14.5 wt % above 500°C in nitrogen and air. The isothermal lifetime was estimated based on the kinetic parameters of nonisothermal degradation and compared with the isothermal lifetime observed experimentally. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 2201–2207, 1999  相似文献   

14.
Poly[aniline‐coN‐(2‐hydroxyethyl) aniline] was synthesized in an aqueous hydrochloric acid medium with a determined feed ratio by chemical oxidative polymerization. This polymer was used as a functional conducting polymer intermediate because of its side‐group reactivity. To synthesize the alkyl‐substituted copolymer, the initial copolymer was reacted with NaH to obtain the N‐ and O‐anionic copolymer after the reaction with octadecyl bromide to prepare the octadecyl‐substituted polymer. The microstructure of the obtained polymers was characterized by Fourier transform infrared spectroscopy, 1H‐NMR, and X‐ray diffraction. The thermal behavior of the polymers was investigated by thermogravimetric analysis and differential scanning calorimetry. The morphology of obtained copolymers was studied by scanning electron microscopy. The cyclic voltammetry investigation showed the electroactivity of poly [aniline‐coN‐(2‐hydroxyethyl) aniline] and N and O‐alkylated poly[aniline‐coN‐(2‐hydroxyethyl) aniline]. The conductivities of the polymers were 5 × 10?5 S/cm for poly[aniline‐coN‐(2‐hydroxyethyl) aniline] and 5 ×10?7 S/cm for the octadecyl‐substituted copolymer. The conductivity measurements were performed with a four‐point probe method. The solubility of the initial copolymer in common organic solvents such as N‐methyl‐2‐pyrrolidone and dimethylformamide was greater than polyaniline. The alkylated copolymer was mainly soluble in nonpolar solvents such as n‐hexane and cyclohexane. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

15.
This study synthesizes thermally sensitive block copolymers poly(N‐isopropylacrylamide)‐b‐poly(4‐methyl‐ε‐caprolactone) (PNIPA‐b‐PMCL) and poly(N‐isopropylacrylamide)‐b‐poly(4‐phenyl‐ε‐caprolactone) (PNIPA‐b‐PBCL) by ring‐opening polymerization of 4‐methyl‐ε‐caprolactone (MCL) or 4‐phenyl‐ε‐caprolactone (BCL) initiated from hydroxy‐terminated poly(N‐isopropylacrylamide) (PNIPA) as the macroinitiator in the presence of SnOct2 as the catalyst. This research prepares a PNIPA bearing a single terminal hydroxyl group by telomerization using 2‐hydroxyethanethiol (ME) as a chain‐transfer agent. These copolymers are characterized by differential scanning calorimetry (DSC), 1H‐NMR, FTIR, and gel permeation chromatography (GPC). The thermal properties (Tg) of diblock copolymers depend on polymer compositions. Incorporating larger amount of MCL or BCL into the macromolecular backbone decreases Tg. Their solutions show transparent below a lower critical solution temperature (LCST) and opaque above the LCST. LCST values for the PNIPA‐b‐PMCL aqueous solution were observed to shift to lower temperature than that for PNIPA homopolymers. This work investigates their micellar characteristics in the aqueous phase by fluorescence spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS). The block copolymers formed micelles in the aqueous phase with critical micelle concentrations (CMCs) in the range of 0.29–2.74 mg L?1, depending on polymer compositions, which dramatically affect micelle shape. Drug entrapment efficiency and drug loading content of micelles depend on block polymer compositions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

16.
Two new energetic salts of 3‐nitro‐1,2,4‐triazol‐5‐one (NTO) were described. Imidazole and 2‐methylimidazole salt of NTO decomposes exothermically at 217 and 258 °C respectively. Detonation parameters calculated for 2‐methylimidazole salt are significantly smaller than that of 2,4,6‐trinitrotoluene (TNT) but these parameters estimated for imidazole salt are comparable with that of TNT. Structure of new compounds were investigated with NMR and IR spectroscopy. Impact and friction sensitivity determined for new compounds are smaller than for pure NTO, so they are more safe during handling.  相似文献   

17.
X‐ray diffraction, infrared (IR), and electrical properties for pure and Er (NO3)3‐doped methyl‐2‐hydroxyethyl cellulose (MHEC) with concentrations of 0.5, 1, 2, 5, 7, and 10 wt % were studied. X‐ray analysis indicates that the addition of Er (NO3)3, which is a crystalline material, to MHEC at concentrations 10 and 13 wt % leads to the formation of crystalline phases in the amorphous polymeric matrix. The appearance of the bending mode ν2 and the combination mode (ν1 + ν4) of Er (NO3)3 in the IR spectra of composite samples indicates the coordination of nitro group in the chains of MHEC. From the IV characteristics, it was found that the charge transport mechanism in MHEC appears to be essentially space charge limited conduction, while the predominant mechanism in the composite samples is Poole–Frenkel. Values of both drift mobility (μ) and the charge carrier density (n) has been reported. The temperature dependence conductivity data has been analyzed in terms of the Arrhenius and Mott's variable range hopping models. Different Mott's parameters such as the density of states, N(EF), hopping distance (R), and average hopping energy (W) have been evaluated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:2352–2361, 2006  相似文献   

18.
Two oxetane‐derived monomers 3‐(2‐cyanoethoxy)methyl‐ and 3‐(methoxy(triethylenoxy)) methyl‐3′‐methyloxetane were prepared from the reaction of 3‐methyl‐3′‐hydroxymethyloxetane with acrylonitrile and triethylene glycol monomethyl ether, respectively. Their homo‐ and copolyethers were synthesized with BF3· Et2O/1,4‐butanediol and trifluoromethane sulfonic acid as initiator through cationic ring‐opening polymerization. The structure of the polymers was characterized by FTIR and1H NMR. The ratio of two repeating units incorporated into the copolymers is well consistent with the feed ratio. Regarding glass transition temperature (Tg), the DSC data imply that the resulting copolymers have a lower Tg than pure poly(ethylene oxide). Moreover, the TGA measurements reveal that they possess in general a high heat decomposition temperature. The ion conductivity of a sample (P‐AN 20) is 1.07 × 10?5 S cm?1 at room temperature and 2.79 × 10?4 S cm?1 at 80 °C, thus presenting the potential to meet the practical requirement of lithium ion batteries for polymer electrolytes. Copyright © 2005 Society of Chemical Industry  相似文献   

19.
以取代苯肼、自制的取代苯甲酰氯为原料,以二氯甲烷为溶剂,在冰浴中合成了8种芳基芳酰肼类化合物,收率78%~90%。产品结构经元素分析、IR、1HNMR确证。产物的IR谱中,在3200~3400cm-1出现两个N—H吸收峰;1HNMR谱中,两个N—H的化学位移在δ8.46~11.38之间;产品的元素分析结果与理论值基本相符。  相似文献   

20.
In this work, two very low band‐gap (~1.0 eV) alternate conjugated copolymers bearing bispyrrolylvinylthiophene‐based polysquaraine backbone (PVTVPS) have been synthesized. In comparison with their analogous polymer with 2‐ethylhexyl side chain on the pyrrole segment, which possesses poor solubility after long‐time storage, the two target polymers with 4‐dodecyloxyphenyl (PVTVPS‐Ph) or (4′‐dodecyloxy‐4‐biphenyl)methylene (PVTVPS‐Ph2) side chains exhibit dramatically improved solubility. Furthermore, PVTVPS‐Ph shows unexpected thermochromism in the Vis–near‐infrared (NIR) region of 600–1100 nm at 80–160°C in solution and thin film. This may be attributed to the presence of relatively rigid phenyl substituent restricting the free rotation between the D (pyrrole) and A (squaraine) segments of the main chain. To our knowledge, this is the first report on NIR thermochromic polysquaraines. Nevertheless, in the case of PVTVPS‐Ph2, no thermochromism could be observed because of the existence of free‐rotating methylene linkage bridge between biphenyl unit and the conjugated polymer skeleton. When compared with PVTVPS‐Ph, PVTVPS‐Ph2 has much improved thermostability and broader absorption property. Hence, PVTVPS‐Ph2 is a more prospective candidate as photovoltaic materials. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

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