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1.
The reactions of chloromethylated divinylbenzene crosslinked polystyrene (CMPS) with polyethylenepolyamines (PEPA), polyethyleneimines (PEI), 2-methyl-2-oxazoline (MeOZO), and the hydrolysis of CMPS–MeOZO reaction products were carried out. The abilities of these products for removing a nonionic surfactant, polyethylene glycol mono-p-nonylphenyl ether (NP, n=10), solutes in water were investigated. Removal rates of NP by and the amounts of NP removed by CMPS–PEPA, –PEI, –MeOZO, and hydrolyzate of CMPS–MeOZO were compared. The adaptability of removal behavior of the products to the Freundlich's adsorption isotherm and the amounts of NP removed by unit masses of the products were investigated. The products also removed an anionic surfactant, sodium dodecylbenzene sulfonate (DBS), solutes in water. The mechanisms for removing NP and DBS were discussed.  相似文献   

2.
A study was made of the removal of viable bacterial cells from sterilized physiological saline (saline) by insoluble polymer beads. The polymers (CMPS–PEI300 and CMPS–PEI600) were prepared by reactions of chloromethylated, divinylbenzene crosslinked polystyrene (CMPS) beads with polyethyleneimines (PEI) (MW = about 300 and 600). The bacterial strain cells used were Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Pseudomonas aeruginosa (P. aeruginosa). Decrease coefficients (D, which corresponds to adsorption rate constant) for the viable cell numbers of E. coli by CPMS–PEI300 and CMPS–PEI600 were 28 and 120 (mL/gh) in saline, respectively. These D's were less than those (72 and 270 mL/gh) in sterilized, distilled, and deionized water (sterilized water). The D's for S. aureus and P. aeruginosa by CMPS–PEI600 were 46 and 76 (mL/g h), respectively. The D for E. coli by CMPS–PEI600 was compared with R (removal coefficient) for that by pyridinium type polymers. Bactericidal activity of PEI600 was examined on E. coli and P. aeruginosa in saline. Also, that of poly(ethylene glycol) 600 was done on E. coli in saline.  相似文献   

3.
Three polystyrene (PS)–polyoxyethylene (POE) block copolymers were synthesized: S-114 and S-123 as copolymers of POE–PS–POE type, and S-61-10 as that of type. Although the copolymers themselves did not remove nonionic surfactant, polyethylene glycol mono-p-nonylphenyl ether (NP, n = 10), in water, the copolymers, which were supported on activated alumina, removed the surfactant. The removal rates of NP by the copolymers supported on the alumina were compared. The effect of initial concentration of NP and the effect of the amount of supported copolymer on the amount of NP removed were studied. The Freuindlich adsorption isotherm was observed between the residual concentration of NP and the amount of NP removed. In the three copolymers supported on the alumina, the amount of removal per unit mass was the greatest for the S-61-10.  相似文献   

4.
For some binary systems, an extended Flory–Huggins equation is applicable to both vaporliquid equilibria (VLE) and liquid–liquid equilibria (LLE) using the same adjustable parameters. New LLE and VLE data are reported for polystyrene (PS) (MW = 100,000)/cyclohexane and for poly(ethylene glycol) (PEG) (MW = 8,000)/water. Experimental results for the PS/cyclohexane system agree well with the semiempirical model, whereas those for PEG/water do not, probably because, for PEG/water, the temperature range of the VLE data is about 55°C lower than that of the LLE data. Excellent fits were obtained for our previously published experimental results for PS/cyclohexane (upper critical solution temperature, UCST), PS/ethyl acetate (lower critical solution temperature, LCST), PS/tert-butyl acetate and PS/methyl acetate (both UCST and LCST), and PEG/water (closed-loop). The semiempirical model also fits well with new data obtained for the polymer blend PS/poly(vinyl methyl ether). © 1993 John Wiley & Sons, Inc.  相似文献   

5.
研究了非离子及阴离子型表面活性剂(聚乙二醇、聚氧乙烯月桂醚和十二烷基苯磺酸钠)对铝酸钠溶液晶种分解制备一水软铝石的影响. 结果表明,十二烷基苯磺酸钠抑制溶液分解及晶体附聚,导致产物粒度细化;聚乙二醇可强化溶液分解,并促进晶体附聚;PEG1000添加量为1 g/L时获得最高分解率(32.39%),较空白提高8.37%;PEG1000添加量为5 g/L时附聚效果最好,产物的中位粒径为23.86 mm,较空白提高4.5%. XRD和热重分析结果表明,添加剂未改变产物晶型,产物均为一水软铝石和三水铝石.  相似文献   

6.
Insoluble polymers adsorbing bacterial cells were prepared by reactions of chloromethylated, divinylbenzene crosslinked polystyrene (CMPS) beads with poly(ethylene glycol) 600 (PEG600), PEG monolaurate (PEGLE), polyethylenimines (PEIs, MW = ca. 300. 600. and 1200, referred to as PEI300, PEI600, and PEI1200, respectively), as well as ethylenediamine (ED) and tetraethylenepentamine (TEP) as polyethylenepolyamines. CMPS-ED and CMPS-TEP were further quaternized with 1-iodooctane (IO) and 1-iodododecane (IDD), respectively. These polymers were brought into contact with Escherichia coli by stirring in sterilized, distilled, and deionized water. Although CMPS-PEG and CMPS-PEGLE did not adsorb the cells, they caused a decrease in the number of viable cells. The decrease seemed to result from the bactericidal action of substances leached from the polymers. CMPS-PEI300, CMPS-PEI600, and CMPS-PEI1200, CMPS-ED-IO, and CMPS-TEP-IDD caused a decrease in the viable cell number by adsorption of the cells to their surfaces. It was observed with a scanning electron microscope that the cells were present on the surfaces of CMPS-PEI600 beads. The decrease coefficient for decrease in viable cell number of E. coli caused by the polymer increased with nitrogen content of the polymer. The adhesion of the cells to CMPS-PEI300, CMPS-PEI600, and CMPS-PEI1200, CMPS-ED-IO, and CMPS-TEP-IDD was due mainly to electrostatic interaction between them.  相似文献   

7.
Poly(1,4-butanediol succinate) copolymers were prepared by melt polycondensation of succinic acid and 1,4-butanediol with 10–50mol% (in feed) of poly(ethylene glycol) (PEG), where molecular weight (MW) of PEG is 200–2000. The reduced specific viscosity of the copolymers increased with incorporation of the PEG component, but a higher PEG content in the copolymers reduced it. The temperature of melting (Tm) and crystallinity decreased with increasing PEG content. Tm depression of the copolymers followed approximately Flory’s equation, suggesting that these are random type copolymers. Tensile strength and elongation decreased with increasing MW and content of PEG. The weight loss of copolymer films in a buffer solution with or without lipase at 37°C, as well as water absorption, increased with increasing PEG content, implying that higher water absorption contributes to hydrolytic degradation of the films. However, the weight loss of copolymers with PEG of lower MW increased greatly in spite of lower water absorption, demonstrating that hydrolytic degradation is influenced by the concentration of degradable ester linkages between succinic acid and PEG segments rather than water absorption. © of SCI.  相似文献   

8.
以苯酚、甲醛、二乙烯三胺为原料制备曼尼希胺(Man - A1),然后以聚乙二醇与液体环氧树脂的反应物(P)为改性剂对Man - A1进行改性,再用苯基缩水甘油醚封端,制得具有自乳性的改性曼尼希胺(Man - A2),最后采用相反转法制得了非离子型水性环氧固化剂.讨论了聚乙二醇相对分子质量、聚乙二醇与环氧树脂物质的量之比以及端羟基环氧聚合物P的含量对乳液的稳定性和粒径的影响.结果表明:以聚乙二醇4 000为原料制备端羟基环氧聚合物P,当聚乙二醇4 000与环氧树脂物质的量之比为3:4,P的添加量为20%时,所得的水性环氧固化剂体系的稳定性最佳,在3 000 r/min的离心机中20 min不分层,平均粒径最小,为0.43 μm,固含量约为50%,胺值为160 mgKOH/g.室温固化后,涂膜硬度4H,耐冲击性50 cm,柔韧性1mm,附着力0~1级,适用期5~6h,耐水性优异.  相似文献   

9.
A series of porous thermoreversible hydrogels were prepared from N‐isopropylacrylamide (90 mol %) and poly(ethylene glycol) methylether acrylate (10 mol %), which was derived from poly(ethylene glycol) monomethylether, N,N′‐methylenebisacrylamide, and porosigen, or poly (ethylene glycol) (PEG) with different molecular weights (MWs). The influence of pore volume in the gel on the physical properties, swelling kinetics, and solute permeation from these porous gels was investigated. The results show that the surface areas, pore volumes, and equilibrium swelling ratios for the porous gels increased with increasing MW of PEG, but the shear moduli and effective crosslinking densities decreased with increasing MW of PEG. The results from the dynamic swelling kinetics show that the transport mechanism was non‐Fickian. The diffusion coefficients of water penetrating into the gels increased with increasing pore volume of the gels. In addition, we also studied solute permeation through the porous gel controlled by temperature. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5490–5499, 2006  相似文献   

10.
Inverse creep     
The copolymerization of epoxy-terminated poly(ethylene glycol methyl ether) (CH3PEG–epoxide) with lactones such as ?-caprolactone (CL) was carried out to prepare the PEG graft poly(ester ether). The methanol-insoluble part of the reaction product was considered to be the graft copolymer. The graft copolymer was prepared using potassium tert-butoxide or sodium methoxide as a catalyst. The apparent number-average molecular weight (M?n) of the graft copolymers increased with an increase in CL concentration and a decrease in the dielectric constant of the solvents. ß-Propiolactone (PL) and δ-valerolactone (VL) were also copolymerized with CH3PEG–epoxide as well as was CL. The apparent composition of the graft copolymers (lactone units/CH3PEG) was greater than the feed ratio of the two monomers in all cases. On the other hand, the composition of copolymers prepared with the copolymerization of low molecular weight epoxides such as phenyl glycidyl ether with VL was almost consistent with the feed ratio of the two monomers. © 1994 John Wiley & Sons, Inc.  相似文献   

11.
Turnip roots, which are readily available in Mexico, are a good source of peroxidase, and because of their kinetic and biochemical properties have a high potential as an economic alternative to horseradish peroxidase (HRP). The efficiency of using turnip peroxidase (TP) to remove several different phenolic compounds as water‐insoluble polymers from synthetic wastewater was investigated. The phenol derivatives studied included phenol, 2‐chlorophenol, 3‐chlorophenol, o‐cresol, m‐cresol, 2,4‐dichlorophenol and bisphenol‐A. The effect of pH, substrate concentration, amount of enzyme activity, reaction time and added polyethylene glycol (PEG) was investigated in order to optimize reaction conditions. A removal efficiency ≥85% was achieved for 0.5 mmol dm?3 phenol derivatives at pH values between 4 and 8, after a contact time of 3 h at 25 °C with 1.28 U dm?3 of TP and 0.8 mmol dm?3 H2O2. Addition of PEG (100–200 mg dm?3) significantly reduced the reaction time required (to 10 min) to obtain >95% removal efficiency and up to 230% increase in remaining TP activity. A relatively low enzyme activity (0.228 U dm?3) was required to remove >95% of three phenolic solutions in the presence of 100–200 mg dm?3 PEG. TP showed efficient and fast removal of aromatic compounds from synthetic wastewaters in the presence of hydrogen peroxide and PEG. These results demonstrate that TP has good potential for the treatment of phenolic‐contaminated solutions. © 2002 Society of Chemical Industry  相似文献   

12.
Lingling Ge 《Polymer》2007,48(9):2681-2691
The microstructure of Triton X-100 (TX-100)/poly (ethylene glycol) (PEG) complex has been investigated by fluorescence resonance energy transfer (FRET), dynamic light scatter (DLS), freeze-fractured transmission electron microscopy (FF-TEM) and 1H NMR technology. The nonionic surfactant TX-100 and pyrene are employed as energy donor and acceptor respectively, and the average distance between them is calculated quantitatively in the systems of TX-100/PEG with different molecular weights (MW). The results of FRET study indicate that the presence of PEG leads to the separation of donor and acceptor in TX-100 micelle, suggesting that PEG chains insert into TX-100 micelles making the microstructure of PEG-bound TX-100 aggregates looser than that of free micelles, which is independent of the MW of PEG. However, FF-TEM, DLS and 1H NMR studies show that the morphology of TX-100/PEG complex depends on the MW of the polymer: PEG with shorter chain (MW < 2000 Da) insert into and wrap around TX-100 micelles and form sphere-like complex, while that with longer chain (MW > 2000 Da) would interact with numbers of TX-100 micelles and form coral-shaped clusters. In addition, the effects of temperature and alcohol on the microstructure of TX-100/PEG complex are studied.  相似文献   

13.
Surfactant/cosurfactant association and emulsion stability   总被引:6,自引:0,他引:6  
The stability of emulsions with an anionic surfactant combined with dodecanol and ethylene glycol dodecyl ether, respectively, was studied. The stability of the emulsion with the nonionic compound as cosurfactant was superior. The results are discussed, with the phase diagrams of water and the cosurfactant as a basis. The phase diagram of the nonionic compound shows a lamellar liquid crystal of superior stability against high water contents.  相似文献   

14.
以1,4-二氯甲氧基丁烷为氯甲基化试剂,通用级聚苯乙烯(PS)为原料,制备了氯甲基化聚苯乙烯(CMPS);将CMPS与聚乙二醇(PEG)6000采用碱催化法制备了PS接枝PEG6000聚合物(PEG6000-g-PS)。对CMPS,PEG6000-g-PS进行傅里叶变换红外光谱分析、X射线光电子能谱分析,对PS,PEG,PEG6000-g-PS进行差示扫描量热法分析、热重分析。结果表明:成功制备了PEG6000-g-PS,且接枝率为12.3%;PEG6000-g-PS的熔融温度为63.03℃,相变焓为15.313 J/g,起始分解温度为314℃,热稳定性良好。  相似文献   

15.
Microemulsion systems with the nonionic surfactant p-tert-octylphenoxy polyethoxyethanol (OP9.5EO), the anionic surfactant dioctyl sulfosuccinate sodium salt (DOSS) and the narrow range nonionic surfactant alkyl polyethylene glycol ether (C10EO5) were used as solvent systems in the catalytic hydrogenation of dimethyl itaconate (DMI) catalysed by the water soluble catalyst complex Rh-TPPTS in order to achieve product isolation and catalyst recycling. The DOSS systems, which are more sensitive to the substrate and catalyst addition allowed for the hydrogenation to proceed with an initial hydrogenation rate about three times higher than with the nonionic surfactants, when the surfactant concentration was 15 wt%. Systems with 3 wt% surfactant were used in order to accomplish catalyst recycling. With a biphasic DOSS mixture a turnover number (TON) of 1,200 mol of DMI hydrogenated per mol of catalyst (Rh) was obtained in 3 consecutive runs. A three-phase system for the OP9.5EO mixture allowed the catalyst to be recycled 3 times and a TON of 1,500 in 4 runs was obtained. A TON of 800 in 2 runs was obtained using a three-phase C10EO5 mixture.  相似文献   

16.
以乙二醇单乙醚和乙酸为主要原料,以四水硫酸铈为催化剂,环己烷为带水剂,合成了乙二醇单乙醚乙酸酯。采用IR、1HNMR等对其结构进行了确证,考察了乙二醇单乙醚和乙酸的摩尔比、催化剂种类和用量、带水剂用量、反应温度、反应时间等因素对反应的影响,得到了适宜的反应条件为:以0.2 mol乙二醇单乙醚为基准,n(乙酸)∶n(乙二醇单乙醚)=1.5∶1,m(四水硫酸铈)∶m(乙二醇单乙醚)=0.05∶1,环己烷9 mL,反应温度130℃,反应时间2.5 h。在该条件下,乙二醇单乙醚乙酸酯收率达97%以上。  相似文献   

17.
In moisture wicking fabrics, fibers with hydrophilic surfaces that are also non‐water soluble are desirable. In poly(lactic acid), PLA, fibers it is expected that the addition of poly(ethylene glycol), PEG, will monotonically increase their wicking rates. In this paper, phase separation was used to create biocompatible, biodegradable, hydrophilic yet non‐water soluble fibers by electrospinning PLA with PEG and PLA‐b‐PEG copolymers. By tuning the thermoelectric parameters of the apparatus, and the chemical properties of the dopes, the amount of PEG in the fibers was improved over prior work; concentration increased by 60% (by weight, wt %) to 16 wt % in the PLA fiber. Instead of the expected increasing wicking rates with PEG concentration, there is a peak at 12 wt %; at greater concentrations, wicking decreases due to PEG crystallization within the PLA (verified via DSC). At 12 wt % PEG from copolymers, the nanofabric's wettability increases to 1300% its original weight. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41030.  相似文献   

18.
Polydimethylsiloxane polyurethane (PDMS‐PU), which was synthesized from PDMS as the soft segment, was blended into a variety of ester‐ or ether‐based soft‐segment waterborne polyurethanes with different concentrations to investigate the crystallization, thermal, and physical properties of the membrane formations. According to X‐ray analysis, the ether‐based PUs, synthesized from soft segments of poly(propylene glycol) (PPG1000) or poly(ethylene glycol) (PEG2000), were found to have maximum crystallinity at a 5% blending ratio of PDMS‐PU, but the ester‐based PU, synthesized from soft segments of polycaprolactone (PCL1250), had decreased crystallinity at a 5% blending ratio. Differential scanning calorimetric analysis revealed that the Tg,s values of PUs were highest when the blending ratio of PDMS‐PU was 5%–10%, except for PU from PCL1250. Moreover, ether‐based PUs showed maximum Tm,h values, but the Tm,h of the ester‐based PU was greatly reduced when PU with PCL1250 was blended with PDMS‐PU. In addition, the PU from PEG2000 had the highest melting entropy. Mechanical property analysis showed that the stress of ether‐based PUs would be increased when PUs were blended with a small amount of PDMS‐PU and that the stress of PU from poly(tetramethylene glycol) (PTMG1000) increased to its greatest value (20–30 MPa). On the other hand, the ester‐based PU, from PCL1250 blended with PDMS‐PU, would have reduced stress. On the whole, the stress and strain of PU from PEG1000 had excellent balance. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 210–221, 2006  相似文献   

19.
非离子型水分散性聚氨酯的制备及性能研究   总被引:5,自引:0,他引:5  
主要讨论了以聚乙二醇为亲水单体,聚醚多元醇N220为多元醇制备非离子水性聚氨酯乳液。讨论了亲水单体的用量,NCO与OH比例对聚氨酯乳液及干膜性能的影响。并比较了阴离子型,阳离子型和非离子型聚氨酯乳液的性能。  相似文献   

20.
Summary Complexation of porcine pepsin (or pepsin A) (EC.3.4.23.1) with poly(ethylene glycol) (PEG) in an aqueous solution was studied as a function of pH and PEG concentration. The addition of PEG increased the reduced viscosity of the enzyme solution at pH 3 but not at pH 4.5. An increase in pH was observed by mixing both PEG and enzyme solutions which were previously adjusted to pH 3. Under conditions of pH 2.5–3 and 50°C, PEG contributed to an increase in the hydrolyzing activity of pepsin towardN-acetyl-l-phenylalanyl-3,5-diiodo-l-tyrosine. These results indicate that pepsin forms a water-soluble complex with PEG mainly through hydrogen bonds between the carboxyl groups in the enzyme and the ether groups in PEG.  相似文献   

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