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1.
In this study, the poly(amidoamine) (PAMAM) G‐2 dendrimer was applied to the jute yarn. Fourier transform infrared spectrophotometry (FTIR) of the dendrimer‐treated jute yarn indicated that all carbonyl groups of the jute fiber have reacted with amino groups of the PAMAM dendrimer. Jute yarns which had been pretreated with PAMAM dendrimer displayed markedly enhanced color strength with reactive dyes, even when dyeing had been carried out in the absence of electrolyte or alkali. Dendrimer‐treated jute yarn showed much better light‐fastness than that of untreated jute yarn. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

2.
The study reports on the synthesis of four novel PAMAM dendrimers of generation 2, modified with 1,8-napthalimide. Their photophysical characteristics have been determined in organic solvents of different polarity (chloroform and N,N-dimethylformamide). The spectral assignments of the dendrimers are dependent on the nature of the substituent at C-4 position of the 1,8-naphthalimide structure. The low quantum yield of fluorescence of the novel materials reveals that a photo-induced electron transfer is proceeding from the core of the dendrimer molecule to the naphthalimide fluorophore located in its periphery. The PAMAM dendrimers thus modified exhibit good photo stability in N,N-dimethylformamide solution.  相似文献   

3.
在DMF溶剂中使用不同代数的整代树枝形聚合物聚酰胺-胺(PAMAM)与1,8-萘二甲酸酐进行酰胺化反应,制备了1,8-萘酰亚胺修饰的3.0G以及5.0G的树枝形聚合物D3、D5。对产物进行红外、紫外-可见吸收、荧光发射、激发光谱以及元素分析的表征,产物与目标产物结构一致。在氯仿与乙醇(体积比为1∶1)的混合溶剂中,由于PAMAM对萘环的固定作用,在萘环浓度相同的情况下,1,8-萘二甲酸酐不形成激发态萘环与基态萘环的激基缔合物,而聚合物D形成了分子内萘环的激基缔合物,在471 nm处产生萘环激基缔合物的荧光发射峰,具有潜在的应用价值。  相似文献   

4.
PAMAM树形分子在油墨废水处理中的应用研究   总被引:2,自引:1,他引:2  
使用聚酰胺-胺(PAMAM)树形分子处理油墨废水,研究了树形分子的代数、溶液的酸度以及树形分子的加药量对色度和COD去除率的影响。研究表明,PAMAM树形分子对油墨废水具有良好的治理效果,在pH值为5.0左右,PAMAM投加量为20mg/L的条件下色度和COD去除率可分别达到98.6%和98.3%。  相似文献   

5.
G. Rajesh Krishnan 《Polymer》2008,49(24):5233-5240
Three generations of polystyrene supported poly(amidoamine) dendrimer were synthesized and characterized. The supported dendrimers were found to be efficient organocatalysts in the nucleophilic ring opening of epoxides by anilines under mild conditions. Higher generation dendrimer showed increased catalytic activity. The polymer supported catalyst was reusable. The catalytic activity of supported dendrimer was compared with the unsupported one and found that the supported dendrimer was a much more active catalyst. The higher activity of the supported dendrimer is assumed to be due to the better hydrophobic/hydrophilic interaction existing between the polystyrene matrix and the polar dendritic chains.  相似文献   

6.
In this study, a hemicyanine dye, trans‐4‐(4‐(diethylamino)styryl)‐1‐ethylpyridinium bromide (DYE‐BD), was synthesised and simulated. The maximum absorption wavelength of DYE‐BD was calculated with the same basis set by using the Gaussian 09 software based on different methods, while time‐dependent density functional theory was applied to simulate the maximum emission wavelength of the designed dye. The changes in enthalpy and Gibbs free energy were simulated at the b3lyp/6‐31G(d) level, and energy changes in the luminescence process were assessed using mathematical methods. Furthermore, DYE‐BD was used to colour acrylic fabric following the typical dyeing procedure for cationic dyes. The photostability of the synthesised dye was analysed using quantum theory and mathematical methods. The synthesised dye, analysed using the Ecological Structure Activity Relationships class program, had no toxicity to aquatic life, while the acrylic fabrics dyed with DYE‐BD met the fluorescent orange requirements for background and combined performance materials according to the EN ISO 20471:2013 standard.  相似文献   

7.
The aim of this article is to provide a comprehensive survey on synthesis, chemical and physico-chemical properties, and applications in several fields, including the biomedical field, of a family of tertiary amino polymers, the poly(amido-amine)s.  相似文献   

8.
A homologous series of hyperbranched polymers (HBPs) was prepared following a well‐defined method and their formation in a polymeric form bearing different extents of branching with amine functional groups at the terminals was verified using different techniques such as Fourier Transform Infrared, 1H Nuclear Magnetic Resonance, Differential Scanning Calorimetry, and Gel Permeation Chromatography. Toughening of a commercially available fast cure epoxy was aimed through reactive blending with the formed HBPs that exhibit variation in polarity and branching according to the relevant synthesis strategy employed for each polymer. The mechanical properties (impact resistance, pull‐off adhesion, and bending) of the resulting coating films pertaining to each epoxy formulation after adhering to metal substrates revealed obvious progress in their performance with respect to a control sample that was hardened exclusively in absence of any HBP. The results were explained on the light of the ability of this class of materials to impose flexibility and dilute the intensive crosslink density associated frequently with the rapid curing of epoxy systems. The extent of gained enhancement for each formulation was accounted for by the molecular architecture of the HBPs, their degrees of branching, polarity, and relative reactive contents of primary amino groups in each case. In addition, the influence of these parameters on a proper wetting over the substrate and morphology of the films in each case was also studied using scanning electron microscopy. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

9.
The cationization of cotton fibers is emerging as an effective tool for solving the environmental problems associated with the dyeing of cotton fabrics with anionic dyes. In this study, the dyeing performance of cationizing agents (Rucomor Bur, Kemifix REA, Optifix F, and Optifix RSL) were examined, and we found that this method had better results compared with normal or existing methods of reactive dyeing. The dye‐bath exhaustion and fixation were determined by the help of an ultraviolet–visible absorbance spectrophotometer on the basis of the maximum absorbance wavelength. Better fixation values were found with the cationizing process than with salty dyeing. The washing and rubbing fastness results were as the same as those of traditional dyeing. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

10.
《Journal of aerosol science》2006,37(11):1643-1648
Poly(amidoamine) (PAMAM) dendrimers generations 2 through 6 were aerosolized by an electrospray aerosol generator and their electrical mobility spectra observed using a differential mobility analyzer (DMA). We succeeded in measuring the electrical mobilities of the monomer and dimer ions of these dendrimers. The experimental results suggested that PAMAM dendrimers are useful as standard particles in the range of a few nanometers.  相似文献   

11.
Light converting greenhouse films are novel plastic films for agriculture. In this study, 4‐methoxy‐N‐allyl‐1,8‐naphthalimide (MOANI) was grafted onto linear low‐density polyethylenes (LLDPE‐g‐MOANI) by melt reactive mixing. The effects of monomer concentration, chamber temperature, and reaction time on grafting degree were systematically studied. Evidence of the grafting reaction was determined by 1HNMR, FTIR, UV–Vis, and fluorescence spectrometry. Dynamic rheological properties, isothermal crystallization kinetics, surface morphologies of LLDPE, LLDPE‐g‐MOANI, and blends of LLDPE and MOANI (LLDPE/MOANI) were also analyzed. In addition, mechanical and fluorescent properties of unpurified LLDPE‐g‐MOANI films were further studied after the UV condensation weathering and acceleration migration test, respectively. We demonstrated that the cross‐linking of LLDPE could be inhibited effectively by the graft of MOANI; the grafted MOANI acted as a nucleation agent to accelerate crystallization; the grafted MOANI effectively inhibited the aging process of LLDPE and the migration of free MOANI to the surface of the unpurified LLDPE‐g‐MOANI film. The modified LLDPE showed the potential application in long‐term light converting films. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42172.  相似文献   

12.
The changes brought about by acetylation, benzoylation and terephthaloylation of some disperse dyes derived from 4–aminoazobenzene on the dyeing and fastness properties are described. Dyes substituted by benzoyl and terephthaloyl groups tended to have better light, wash and sublimation fastness on polyester. The dyes showed good build–up when these groups are coupled with an N–β–cyanoethyl group. Acylation of azo dyes resulted in poor substantivity and poor fastness properties on nylon 6.  相似文献   

13.
改性石墨通过接枝,合成了聚酰胺-胺(PAMAM)修饰的氧化石墨烯复合吸附材料(GO/PAMAMs)。考察了温度、pH、Pb(2+)浓度和吸附时间对GO/PAMAMs吸附Pb(2+)浓度和吸附时间对GO/PAMAMs吸附Pb(2+)效果的影响。结果表明,GO经PAMAMs修饰后,彼此间形成共价键连接;在25℃、pH为6,Pb(2+)效果的影响。结果表明,GO经PAMAMs修饰后,彼此间形成共价键连接;在25℃、pH为6,Pb(2+)浓度为500 mg/L,吸附时间为4 h时,GO/PAMAMs对Pb(2+)浓度为500 mg/L,吸附时间为4 h时,GO/PAMAMs对Pb(2+)的平衡吸附量达到337 mg/g。该吸附过程可以用Lagergren方程和Langmuir模型来描述,由化学反应控制,升温有利于吸附。  相似文献   

14.
The optical absorption of poly(methyl methacrylate) (PMMA), doped with perylene dye, prepared by both thermal polymerization and casting methods, has been measured before and after exposure to filtered or unfiltered light using xenon arc lamp or day light. The optical band gap of thermally polymerized PMMA was reduced by doping with perylene dye or exposure to UV radiation. Study of DSC and FTIR measurements confirmed that the samples prepared by thermal polymerization are more stable than solvent‐cast samples. © 2002 Society of Chemical Industry  相似文献   

15.
The spin pack is an essential component of melt spinning processes. However, the age of the spin pack can affect the physical properties of polymers. The dyeing properties of poly(ethylene terephthalate) fibres over time in relation to spin pack age were investigated in the present study. With an increase in the age of the spin pack, an increase in colour strength and a decrease in fibre crystallinity were observed. The crystallinity decrease of the fibres through spin pack age was explained by the increase in polymer melt temperature due to increase in spin pack pressure.  相似文献   

16.
Combining dyeing and wrinkle‐resistance finishing of cotton in a one‐step process using a hemicyanine fluorescent dye DHEASPBr‐C2 was investigated in this paper. Fourier transform infrared spectroscopy, a fixation test, extraction with boiling N,N‐dimethylformamide, and a colour fastness test certified that DHEASPBr‐C2 was linked to the cotton fibre through covalent bonds. The results showed that dyed cotton fabric using DHEASPBr‐C2 had an obvious fluorescent effect in the range 550–700 nm, and the emission peak location was 588–590 nm. In addition, the dyed fabric met the EN471:2003 standard for chromaticity and could be used in high‐visibility warning clothing.  相似文献   

17.
Modified dyes were obtained by grafting of disperse dyes with octavinyl polyhedral oligomeric silsesquioxanes (POSS) using a Friedel‐Crafts alkylation reaction and using different ratios of POSS and the original disperse dye. The modified dyes are used to dye aromatic poly(l,3,4‐oxadiazole) (p‐POD) fiber to improve its UV resistance. Then the structure of the modified dye is characterized by Fourier transform infrared spectroscopy and NMR, and the effects of the structure of the modified dye and the dyeing conditions on the UV resistance and color strength (K/S value) of the dyed samples are investigated. The results indicated that the UV adsorption peaks of the modified dye solutions are located at the specified UV wavelengths. The UV resistance of the p‐POD fiber dyed with the modified dye (1:3) can be effectively improved, and the dyed p‐POD fiber can obtain a higher K/S value simultaneously. During the dyeing process, increasing the dyeing temperature and prolonging the dyeing time are both beneficial in improving the anti‐UV ability of the dyed p‐POD fiber; these changes can effectively promote the fixation of dye molecules into p‐POD fibers due to stimulating the motion of dye molecules and p‐POD macromolecules. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44745.  相似文献   

18.
Poly(amidoamine) (PAMAM) dendrimers have attracted attention because of their well‐defined molecule structures and chemical versatility, which also complicate the mechanism of interactions between metal ions and PAMAM dendrimers. To further understand the complexation of dendrimers with metal ions, the interactions between Pd2+ ions and G4.5‐COOCH3 PAMAM dendrimers were investigated by UV‐vis and FTIR spectrophotometric method. The results show that the addition of K2PdCl4 results in covalent attachment of the PdCl alcoholysis product of this complex to tertiary amines within the dendrimers under the appropriate conditions. This process was also supported by X‐ray photoelectron spectroscopy data of the new complex which indicated a 1 : 3 Pd/Cl ratio. The maximum loading of 80 Pd2+ ions within the G4.5‐COOCH3 dendrimers and the best pH value of 8.3 for complexation system are also obtained. Details regarding the Pd species present in solution of different chemical environments are reported. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

19.
Synthesis of poly(N-vinylformamide) (PNVF) and its subsequent hydrolysis to convert it to poly(vinyl amine) (PVAm) were performed. Kinetics of acidic and basic hydrolysis of poly(N-vinylformamide) (PNVF), and products of hydrolysis were investigated by using Fourier transform infrared, size exclusion chromatography, 1H NMR, and 13C NMR spectroscopies, and thermogravimetric analysis. It was observed that amide groups did not completely transform into amine groups by acidic hydrolysis of PNVF while the conversion of amides into amine groups via basic hydrolysis of PNVF was complete in 12 h, as confirmed by spectroscopic measurements. Results of extensive characterization revealed significant structural and conformational differences between acidic and basic hydrolysis products. Fluorescence spectroscopy was used for the first time to follow the conversion of amide groups into amine groups. The fluorescence intensity of PVAm obtained from basic hydrolysis of PVNF showed significant increase with amide/amine conversion. Finally, PVAm obtained from acidic hydrolysis of PNVF demonstrated potent antimicrobial activity, 10–20 times more, against common pathogens for example, C. albicans as fungal strain and E. coli, S. aureus, B. subtilis, and P. aeruginosa as bacterial strains as compared to PVAm obtained from basic hydrolysis.  相似文献   

20.
孟启  吴桂勇  李丹凤  陈娟娟  孙小强 《化学试剂》2011,33(3):215-218,223
以2,4,6,三氯-1,3,5-三嗪为核(GO)与亚胺基二乙酸二乙酯进行取代反应制得具有枝化的含有酯基官能团的树枝状化合物(G0.5),然后依次与乙二胺、丙烯酸甲酯和乙二胺反应分别制得含有1,3,5-三嗪核的G1.0、G1.5和G2.0代的树枝状化合物.采用FT-IR、1HNMR、13CNMR和ESI-MS对所合成的化...  相似文献   

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