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1.
张丽云  周永红 《精细化工》2012,29(9):860-865
以硬脂酸、单乙醇胺、环氧乙烷、葡萄糖为原料制备了不同环氧乙烷(EO)聚合度的硬脂酸单乙醇酰胺聚氧乙烯醚葡萄糖苷类非离子表面活性剂。该糖苷类表面活性剂在烷基和葡萄糖分子之间引入非离子表面活性剂中常见的亲水基团。通过IR和1HNMR对产物结构进行表征,并测试了该类表面活性剂的最低表面张力(γCMC)为30~38 mN/m,临界胶束质量浓度(CMC)为0.01~0.1 g/L。研究了EO聚合度(n)对产品表面物理化学性能的影响,随着n的增加,CMC、乳化性能、吸湿保湿性能均增加。不同聚合度的产物均有很好的泡沫性能和硬水稳定性。  相似文献   

2.
A new approach to prepare chemically modified carboxymethyl chitosan (CM) derivatives was reported, from which initially CM was prepared from chitosan, then N‐quaternary ammonium group was introduced by the reaction of CM with 2,3‐epoxypropyl trimethylammonium. The structures of the derivatives were characterized by FTIR, XRD, 13C‐NMR, and gel permeation chromatography. The capability of moisture‐absorption and moisture‐retention was investigated. It was found that the moisture‐absorption and moisture‐retention ability of the new derivatives quaternized carboxymethyl chitosan (CMQ) are higher than not only that of CM but also that of chitosan quaternary (Q) and carboxymethyl group and quaternary ammonium group are in synergistic effect. Relationships between molecular structures (including degree of substitution of carboxymethylation group, degree of substitution of quaternary group, and molar mass) and functions of CMQ were also studied. The moisture absorption kinetics of CMQ was discussed and the diffusion of water molecules in it looks likely to be non‐Fickian type. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1303–1309, 2006  相似文献   

3.
Three novel thiourea‐based non‐ionic surfactants, 3‐decanoyl‐1,1‐diphenylthiourea, 3‐dodecanoyl‐1,1‐diphenylthiourea and 1,1‐diphenyl‐3‐tetradecanoylthiourea were synthesized from carbonyl chlorides, potassium thiocyanate and amines in high yield. The synthesized compounds were characterized by different techniques like 1H NMR, 13C NMR, FTIR and UV‐Visible spectrophotometry. These surfactants are soluble in nonpolar and polar organic solvents and resist solubility in water due to the presence of thiourea group. Electronic absorption spectroscopy was used to evaluate their critical micelle concentration (CMC) in different solvents. The CMC was found to decrease with increase in hydrophobic carbon chain length as expected. Moreover, the effect of pH on their spectral transition was investigated and the two peaks were found to merge in highly alkaline conditions.  相似文献   

4.
In the human body, the black‐brown biopigment eumelanin blocks harmful ultraviolet (UV) radiation. In the plastics industry, additives are often added to polymers to increase their UV‐absorption properties. We herein report an assessment of the biopigment eumelanin as a nature‐inspired additive for plastics to enhance their UV absorption. Since eumelanin is produced by natural sources and is nontoxic, it is an interesting candidate in the field of sustainable plastic additives. In this work, the eumelanin‐containing films of commercial ethylene–vinyl acetate copolymer, a plastic used for packaging applications, were obtained by melt compounding and compression molding. The biopigment dispersion in the films was improved by means of the melanin free acid treatment. It was observed that eumelanin amounts as low as 0.8 wt% caused an increase of the UV absorption, up to one order of magnitude in the UVA range. We also evaluated the effect of eumelanin on the thermal stability and photostability of the films: the biopigment proved to be double‐edged, working both as UV‐absorption enhancer and photo‐prooxidant, as thermogravimetric analysis and infrared spectroscopy revealed. © 2019 Society of Chemical Industry  相似文献   

5.
Carboxymethyl cellulose (CMC) composite films were prepared from CMC solutions (2% w/v) containing multiwalled carbon nanotubes (MWCNT) as nanofiller and glycerol (25% w/w CMC) as plasticizer. Tensile strength, elongation at break (EAB), young's modulus, water solubility, water swelling, water uptake, and water vapor permeability (WVP) for CMC films were 27.5 ± 2.5 MPa, 11.2 ± 0.8%, 198 ± 18 MPa, 57 ± 1.5%, 738 ± 25%, 124 ± 4%, and 0.55 ± 0.036 g.mm/m2.kPa.h, respectively. By increasing the relative humidity from 11.4 to 85.5%, the moisture absorption (MA) of CMC films was increased from 4 to 38%. Incorporation of MWCNT into the matrix caused a significant increase in the tensile strength, decrease in EAB, increase in young's modulus, decrease in water solubility, decrease in water swelling, decrease in water uptake, and decrease in MA. CMC/MWCNT films containing 1% MWCNT showed the lowest WVP. Scanning electron microscopy showed a good dispersion of MWCNT in the CMC matrix. CMC/MWCNT films containing >1% MWCNT showed significant antibacterial activities against both Gram‐positive and Gram‐negative bacteria in a dose‐dependent manner. Thus, good mechanical properties and water resistance along with strong antibacterial activities make CMC films grafted with MWCNT as a suitable packaging material. POLYM. COMPOS., 36:145–152, 2015. © 2014 Society of Plastics Engineers  相似文献   

6.
Insoluble nanoporous cyclodextrin (CD) polymers were synthesized using bifunctional isocyanate linkers. The ability of these polymers to remove selected organic pollutants from water at varying concentrations was studied. The investigated pollutants were selected high‐priority chlorinated disinfection by‐products (DBPs) and a common odour‐causing compound in water, 2‐methylisoborneol (2‐MIB). The unpleasant musty odour imparted by 2‐MIB and geosmin in water can be detected by the human nose even at ng L?1 (parts per trillion) levels. Pre‐concentration and extraction of water samples containing low levels of pollutants was performed using solid phase extraction (SPE) and subsequently quantified by gas chromatography‐mass spectrometry (GC/MS). Here we show that the CD polymers demonstrate excellent absorption efficiency (>99%) with respect to the organic pollutants, considerably better than granular activated carbon (GAC). The recyclability efficiency of these CD polymers is also reported. Copyright © 2007 Society of Chemical Industry  相似文献   

7.
A novel ultraviolet (UV) absorber, 5,5′‐disulfide‐bis[2‐(2‐hydroxy‐3,5‐di‐tert‐butylphenyl)‐2Hbenzotriazole] (DSBHTBB) was synthesized. Its structure was characterized by FTIR, NMR, UV, FABMS, and elemental analysis. In comparison with the common commercial benzotriazole UV absorbers, the absorption maximum of DSBHTBB (364 nm) is red shifted by about 20 nm, and the molar extinction coefficient (56,800, in CHCl3) is much greater. With those properties the bisbenzotriazole could be applied as an efficient UV absorber for the protection of polymeric materials and sensitive skin from longer‐wavelength (near‐visible) ultraviolet light. The experimental results showed that DSBHTBB can greatly inhibit the discoloration under irradiation of poly (vinyl chloride) (PVC) containing an organic antimony stabilizer. J. VINYL ADDIT. TECHNOL., 13:195–200, 2007. © 2007 Society of Plastics Engineers  相似文献   

8.
A series of chitosans with various molecular weights from 1.2 × 103 to 30.0 × 104 were prepared by oxidative degradation with H2O2 and characterized by IR, 13C‐NMR, and gel permeation chromatography. Their carboxylic contents increased with a decrease in molecular weight (Mw). The moisture‐absorption and moisture‐retention capacities of resulting chitosans were dependent on both the molecular weight and the degree of deacetylation (DD). Microcalorimetry was first used to study the kinetics of action of the chitosans on a strain of Staphylococcus aureus at pH 7. The antibacterial activity of the water‐soluble chitosan against S. aureus, Escherichia coli, and Salmonella typhi was evaluated by the conventional agar plate method at pH 7. The water‐soluble product with Mw of 0.45 × 104 from initial chitosan of DD of 90% showed high moisture‐absorption and moisture‐retention capacities, and <2% concentration can completely inhibit the growth of these bacteria. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1724–1730, 2002  相似文献   

9.
A series of hyperbranched poly(citric polyethylene glycol) (PCPEG) materials with varied polyethylene glycol (PEG) chain lengths as plasticizers were mixed with maize starch (MS) via cooking and film‐forming. The structure, pasting property, plasticization, aging property, moisture absorption and compatibility of plasticized starches were studied by means of Fourier transform infrared spectroscopy, X‐ray diffraction, rapid viscosity analysis, tension testing, moisture absorption measurements and scanning electron microscopy. Compared with PEG and citric acid, PCPEG was more effective in promoting starch chain movement and inhibiting the retrogradation of starch film. Also, PCPEG/MS had smaller moisture content. The longer the plasticizer chain, the better were the aging resistance and moisture resistance of starch. But with an increase of PEG chain length, mechanical properties of PCPEG/MS deteriorated and the compatibility between PCPEG and MS decreased. The hyperbranched derivative of PEG with longer chain exhibited improved plasticization and compatibility with starch. © 2019 Society of Chemical Industry  相似文献   

10.
Poly (o‐toluidine) (POT) salts doped with organic sulfonic acids (β‐naphthalene sulfonic acid, camphor sulfonic acid, and p‐toluene sulfonic acid) were directly synthesized by using a new solid‐state polymerization method. The FTIR spectra, ultraviolet visibility (UV–vis) absorption spectra, and X‐ray diffraction patterns were used to characterize the molecular structures of the POT salts. Voltammetric study was done to investigate the electrochemical behaviors of all these POT salts. The FTIR and UV–vis absorption spectra revealed that the POT salts were composed of mixed oxidation state phases. All POT salts contained the conducting emeraldine salt (half‐oxidized and protonated form) phase; the pernigraniline (fully oxidized form) phase is predominant in POT doped with β‐naphthalene sulfonic acid, and POT doped with p‐toluene sulfonic acid had the highest doping level. The X‐ray diffraction patterns showed that the obtained POT doped with organic sulfonic acids were lower at crystallinity. The conductivity of the POT salts were found to be of the order 10?3‐10?4 S/cm. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1630–1634, 2005  相似文献   

11.
将2,4-二羟基二苯甲酮(UV-0)、聚乙二醇单甲醚(mPEG)与丙烯酰氯反应合成中间体2-羟基-4-丙烯酸酯基二苯甲酮(2H4ABP)和聚乙二醇单甲醚丙烯酸酯,然后通过自由基溶液共聚合,将聚乙二醇单甲醚丙烯酸酯与2H4ABP、丙烯酸进行共聚合合成了一系列梳状水溶性高分子紫外线吸收剂。采用FT-IR、1H-NMR、UV等手段对产物进行了结构表征。紫外测试结果表明产物在244、291、340 nm处有强紫外吸收,与UV-0相比发生了明显红移。通过分光光度计测定计算了产物的紫外吸收效果残存率并考察了产物的光稳定性,结果表明产物有较好的光稳定性。  相似文献   

12.
Uniform polyaniline (PANI) nanoparticles with typical sizes of about 50 nm were electropolymerized on indium tin oxide surfaces in the presence of Co2+, Ni2+, Cu2+, or Zn2+. According to shaping theory, we first suggest the reason forming PANI spherical particles. Their conductivity, UV‐vis spectra, FTIR spectra, X‐ray diffraction, and thermogravimetric analysis were investigated. The conductivities and crystallinity of PANI doped with these ions are higher than those of PANI doped with HCl (PANI/HCl). Both UV‐vis absorption spectra and FTIR spectra indicate the interactions between Co2+, Ni2+, Cu2+, or Zn2+ and PANI chains. TG analysis also shows that the thermal stability of PANI doped by Co2+, Ni2+, Cu2+, or Zn2+ is lower than that of PANI/HCl. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   

13.
Ag colloidal particles stabilized by poly (N,N′‐methylene bis‐acrylamide N‐aminoethyl piperazine) (MBA‐AEPZ) were prepared. The Ag+ ion concentration and reaction temperature were studied on the size and size distribution of Ag colloidal particles, which were determined from the ultraviolet (UV) plasmon absorption band and transmission electron microscopic (TEM) analyses. The data show that poly(MBA‐AEPZ) behaves like lower molecular mass stabilizers; some polymers surround the surface of the Ag colloidal particles and the particle size can be controlled by a change in the Ag+ ion concentration and reaction temperature. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3701–3705, 2007  相似文献   

14.
A novel hindered amine ligand, mono‐2,2,6,6‐tetramethyl‐4‐piperidyl‐succinate (MTPS), has been designed to chelate europium(III) ion with 1,10‐phenanthroline (Phen) as a coligand to prepare polymer photostabilizer. The luminescent property of the stabilizer and its efficiency of protecting polymer matrix from photodegradation have also been investigated. Under UV excitation, the stabilizer has red light emission in both ethanol solution and polypropylene (PP) matrix. The PP sheets containing the stabilizer display significantly improved photostability, which may be attributed to MTPS which scavenges radical, as well as Phen which makes the complex dissipate the absorbed ultraviolet light in a harmless manner. These preliminary results demonstrate that the introduction of the stabilizer can endow polymer matrices not only excellent photoluminescent properties but also improved photostability. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1399‐1405, 2013  相似文献   

15.
菁染料和份菁染料溶液的光降解机理的研究   总被引:1,自引:0,他引:1  
利用UV-Vis吸收光谱仪和光化学反应器,研究了菁染料和份菁染料溶液的光降解动力学,认为染料在乙腈溶液中的光褪色反应服从假一级或零级动力学,利用GC/MS光谱仪检测了染料的光降解产物,与相应的份菁染料相比,携带正电荷的菁染料具有相对较好的光稳定性,研究结果表明,菁染料光降解反应的中间体可能是染料的半氧化态Dye^ ,并利用纳秒级闪光光解技术研究了Dye^ 的瞬态吸收光谱。  相似文献   

16.
A novel method for attaching fluorescein (via its epoxy derivative) to water‐soluble chitosan, and the temperature/pH‐sensitive qualities of fluorescence were investigated. 3‐Epoxypropoxy fluorescein (EPF) was firstly synthesized by the reaction between fluorescein and epichlorohydrin, and then water‐soluble chitosan bearing fluorescein (CS‐EPF) was prepared via ring‐opening reaction with EPF. They were characterized by the methods of 1H NMR, MS, IR, UV–Vis, and luminescence spectra, respectively. The chemiluminescent and photophysical behaviors of EPF and CS‐EPF were studied in detail. The results showed that the fluorescent chitosan could still provide temperature and pH sensitivities similar to that of fluo‐ rescein, achieving better long‐term stability and fast equilibrium response. CS‐EPF had an excellent linear response between relative fluorescence intensity and temperature in the range of 0–60°C and two linear relationships between relative fluorescence intensity and pH in 0.0–4.14 and 8.15–13.20, respectively. This investigation may provide a convenient way to prepare low‐cost and multifunctional macromolecule biomaterial to probe pH and temperature in biological systems. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3960–3966, 2007  相似文献   

17.
A novel functional polysiloxane (PSBP) bearing benzophenone derivatives as UV absorbing side groups was synthesized by hydrosilylation of polyhydromethylsiloxane (PHMS) with 2‐hydroxy‐4‐(β‐hydroxy‐γ‐allyloxy)propyloxy benzophenone (HHAPB). The chemical structure, film morphology, and the softening fabric property of the synthesized polysiloxane were characterized and investigated by spectrum analysis, atomic force microscope (AFM), and Kawabata evaluation system. The experiment results indicated that PSBP was not only an excellent polymeric UV‐absorber, which showed intensive ultraviolet absorptions respectively, at wavelengths of 243.2, 288.2, and 325.4 nm, but could exhibit a nonhomogeneous, some rough structure film on silicon wafer substrate. In addition, the functional side group, benzophenone derivative as well as its mass ratio to PSBP has an influence on the performance of the synthesized polysiloxane. As the mass ratio decreased from 31.48 to 12.87%, the molar extinction coefficients εmaxmax = 288.2 nm) of the PSBP fluids lowered from 3.4564 × 105 to 1.5763 × 105, but while the softening fabric properties of PSBP on cotton fabrics increased. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 680–687, 2007  相似文献   

18.
UV absorbers for treating cotton textiles with the aim of increased protection against harmful effects of UV component of solar radiation have been prepared by reactions of five different aminophenylsulfobenzotriazoles with the condensation product of 4‐aminophenyl‐sulfatoethylsulfone and cyanuric chloride. The UV absorbers with two different reactive groups (monochlorotriazine and aromatic vinylsulfone), capable of formation of covalent bonds with hydroxyl groups of cellulose, were applied to one cellophane foil and two cotton fabrics of different porosities. This treatment increased the ultraviolet protection factor from a value of UPF = 3 to UPF = 100 and above. For attaining a high UPF value, the cotton material should exhibit low porosity. The UV absorbers with 2‐hydroxyphenyl group are stable in light and do not fluoresce on the fabric on contrary to derivatives without 2‐hydroxyphenyl group or with 2‐methoxyphenyl group. The high photostability of absorbers is explained by the possibility to disperse the absorbed energy of UV radiation in the form of harmless energy such as IR radiation (heat) through the reversible hydrogen bond between phenolic hydroxyl group and triazine cycle. The UV filters block the effect of optical brightening agents on cotton by quenching the fluorescence. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

19.
Montmorillonite (MMT) was modified with carboxymethylcellulose (CMC). The X‐ray diffraction (XRD) and FTIR analyses showed that the CMC chains had intercalated into the MMT sheets, and the strong chemical interaction between the ether bonds from CMC and Si? O bonds from MMT was the driving force for intercalation. Polyacrylate (PAA)/modified MMT superabsorbent nanocomposites were fabricated by effectively dispersing the modified MMT in acrylic acid solution and polymerizing the acid. The superabsorbent composites were characterized by XRD, TEM, and FTIR. The influence of modified MMT, weight ratio of CMC to MMT, and modified MMT content in the nanocomposites on the water absorbency was investigated. Results showed that the introduction of pure MMT could decrease the water absorbency of the gel, but adding modified MMT could not only effectively increase the water absorbency of the gel, but also improve its water retention ability. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

20.
A study of the interaction of commercial black ink with a UV‐curable polyurethane acrylate (PUA) is presented. Diffusivity and solubility in PUA cured using different UV dosages, and subjected to different post‐UV curing conditions, were studied, as was the swelling produced by such sorption. Experiments were also conducted using water, to serve as a benchmark and compare with the effect of ink. The percentage ink absorption was found to decrease with higher degree of cure. In addition, through desorption measurements, ink induced swelling of PUA processed under different conditions was determined. The degree of swelling per unit solvent uptake was observed to increase with the degree of cure. PUA was determined to be more prone to moisture rather than solvent uptake. However, the coefficient of moisture expansion (CME) was found to be ~ 35% lower than the coefficient of ink expansion (CIE) for a fully cured PUA. © 2006 Wiley Periodicals, Inc. JAppl PolymSci 103: 1985–1991, 2007  相似文献   

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