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1.
With the increasing emphasis on the environment and the need to find environmentally friendly solvent systems, ionic liquids
(IL)s have been emerging as promising green solvents to replace conventional solvents in recent years. They possess unique
properties such as nonvolatility, low toxicity, ease of handling, nonflammability and high ionic coductivity; thus they have
received much attention as green media for various chemistry processes. This report provides an extensive overview of use
of ILs in polymers chemistry and technology. 相似文献
2.
新型绿色溶剂--室温离子液体 总被引:5,自引:0,他引:5
室温离子液体是一种具有特殊性质的液体,具有较低的熔点、良好的导电性和可以忽略的蒸气压等优点,已被应用到诸多领域。作为一种高效绿色溶剂,室温离子液体在化学分离、催化、电化学等方面发挥着重要的作用。对离子液体的种类、性质、制备方法及其在绿色化学中的应用进行了介绍。 相似文献
3.
4.
Ionic liquids (IL)s have been recognized as ‘green’ alternatives to the organic solvents in a range of synthesis, catalysis and electrochemistry due to their unique chemical and physical properties. In this investigation, a series of organosoluble, thermally stable and optically active hydroxyl-containing poly(amide–imide)s (PAI)s were prepared via polycondensation reaction of an aromatic diamine, 3,5-diamino-N-(4-hydroxyphenyl)benzamide (4), and different chiral amino acid-based diacids (3a–3e) in the presence of molten tetrabutylammonium bromide as a molten IL and triphenyl phosphite under classical heating method. This process is safe and green since toxic and volatile organic solvents such as N-methylpyrrolidone (NMP) and N,N′-dimethylacetamide (DMAc) were eliminated. The resulting new polymers were obtained in good yields with inherent viscosities ranging between 0.23 and 0.54 dL g?1 and were characterized by Fourier transform infrared spectroscopy, specific rotation, powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis, elemental analysis, and in some cases by 1H-NMR techniques. The FE-SEM micrographs and XRD showed that the synthesized PAIs were nanostructured and amorphous polymers. The effect of ultrasonic irradiation on the size of polymer particles was also investigated and the results showed that the size of polymer nanoparticles after ultrasonication became smaller than the size of them, before ultrasonic radiation. All of the polymers were readily soluble in many organic solvents such as N,N′-dimethyl sulfoxide, DMAc and NMP. 相似文献
5.
María Teresa García Ignacio Gracia Gema Duque Antonio de Lucas Juan Francisco Rodríguez 《Waste management (New York, N.Y.)》2009,29(6):1814-1818
Dissolution with suitable solvents is one of the cheapest and more efficient processes for polystyrene waste management. In this work the solubility of polystyrene foams in several solvents benzene, toluene, xylene, tetrahydrofuran, chloroform, 1,3-butanediol, 2-butanol, linalool, geraniol, d-limonene, p-cymene, terpinene, phellandrene, terpineol, menthol, eucalyptol, cinnamaldheyde, nitrobenzene, N,N-dimethylformamide and water has been determined.Experimental results have shown that to develop a “green process” the constituents of essential oils, d-limonene, p-cymene, terpinene, phellandrene, are the most appropriate solvents. The action of these solvent does not produce any degradation of polymer chains. The solubility of the polymer in the mentioned solvents at different temperatures has been investigated. The solvent can be easily recycled by distillation. 相似文献
6.
7.
A short and green method for the preparation of optically active aromatic polyamides (PAs) using tetrabutylammonium bromide
(TBAB) as a molten ionic liquid is reported. Polycondensation reactions of amino acid containing diacid (2S)-5-(4-methyl-2-phthalimidylpentanoylamino)isophthalic
acid with various commercially available diisocyanates in molten TBAB as a green medium or in N-methylpyrrolidone as common organic solvent with or without dibutyltin dilaurate as a catalyst under microwave irradiation
were carried out. Various PAs were obtained with high yields and moderate inherent viscosities in the rang of 0.30–0.57 dL/g.
The obtained polymers were characterized by FT-IR, specific rotation measurements, and representative of them by 1H NMR and elemental analysis techniques. Thermal properties of PAs were evaluated by thermogravimetric analysis and the results
showed that the 10% weight loss temperature in a nitrogen atmosphere for four representative samples were more than 258 °C,
which indicates that the resulting PAs have good thermal stability as well as excellent solubility. 相似文献
8.
Miwa Setoyama Takeshi Kato Kazuya Yamamoto Jun-ichi Kadokawa 《Journal of Polymers and the Environment》2013,21(3):795-801
This paper reports the preparation of chitin/cellulose films compatibilized with polymeric ionic liquids. In-situ (co)polymerization of polymerizable ionic liquids, 1-(3-methacryloyloxypropyl)-3-vinylimidazolium bromide (1) and 1-methyl-3-vinylbenzylimidazolium chloride (3), was carried out in the presence of a radical initiator, AIBN, in the chitin/cellulose solution with ionic liquid solvents (1-butyl-3-methylimidazolium acetate and chloride, BMIMOAc and BMIMCl, respectively), followed by the appropriate procedure to give the desired films. The presence of the polymeric ionic liquid in the film was confirmed by the IR measurement. The powder X-ray diffraction analysis suggested that crystalline structures of the polysaccharides were largely disrupted in the film, as same as that of a chitin/cellulose film prepared by the AMIMOAc/BMIMCl system. These results were different from the XRD result of a chitin/cellulose film prepared by the 1-allyl-3-methylimidazolium bromide/BMIMCl system reported in our previous study, in which some crystalline structures were still remained in the film. Furthermore, the mechanical properties of the present films were evaluated by tensile testing, which were affected by the molar ratios of the polymeric ionic liquids to the polysaccharides and the compositional ratios of the two units 1 and 3. 相似文献
9.
Shadpour Mallakpour Farhang Tirgir Mohammad R. Sabzalian 《Journal of Polymers and the Environment》2010,18(4):685-695
Ionic liquids (ILs) have been accepted as ‘green’ alternatives to the organic solvents in a range of synthesis, catalysis
and electrochemistry, because of their distinctive chemical and physical properties. In this investigation, N,N′-(pyromellitoyl)-bis-l-tyrosine dimethyl ester as a chiral bioactive diphenolic monomer was prepared in three steps. The polycondensation of this
monomer with various aromatic and aliphatic diisocyanates such as 4,4′-methylene-bis-(4-phenylisocyanate) (6a), toluylene-2,4-diisocyanate (6b), isophorone diisocyanate (6c) and hexamethylene diisocyanate (6d) were carried out in the presence of tetrabutylammonium bromide as a molten IL under microwave irradiation conditions and
was compared with polymerization in traditional solvent like N-methyl-2-pyrrolidone. The results show that IL efficiently absorbs microwave energy, thus leading to a very high heating
rate. Thus IL method is safe and green since toxic and volatile organic solvents were eliminated. All of the novel poly(urethane-imides)
(PUIs) showed good solubility in various organic solvents. The obtained new polymers were characterized with FT-IR, 1H-NMR, elemental and thermogravimetric analysis techniques. Thermogravimetric analysis (TGA) of two representative PUIs demonstrated
that they are rather thermally stable. In vitro toxicity studies showed that the synthetic materials are biologically active
and they are nontoxic to microbial growth then could be classified as bioactive and biodegradable compounds. 相似文献
10.
Lu Li Bing Yuan Shi-Wei Liu Shi-Tao Yu Cong-Xia Xie Fu-Sheng Liu Li-Juan Shan 《Journal of Polymers and the Environment》2012,20(2):388-394
Chitosan oligomers because of its water solubility has some special physiological functions, such as binding lipid, affecting the mitogenic response, restraining the growth of tumors, and was widely used in cosmetics and health. H2O2/Gly (Glycine) series ionic liquids system, a new solvable-catalytic system, was an efficient clean process for preparation of chitosan oligomers. The effects of the anions of Gly series ionic liquids on the solubility and degradation for chitosan were investigated, and the results showed that [Gly]Cl aqueous solution was of good solubility and assistant degradation for chitosan. In additional, the mechanism for oxidative degradation of chitosan in ionic liquids (ILs) was studied. The effect on the property of chitosan oligomers catalyzed by H2O2, in two different kinds of solvents (HAc and [Gly]Cl) were compared. It was found that the performance of moisture absorption and retention of chitosan oligomers using ionic liquid aqueous solution as solvent was better than that using HAc aqueous solution as solvent, and even superior to that of hyaluronic acid. Furthermore, [Gly]Cl could be easily separated from the product and reused with only slight loss. It could provide an efficient and environmental friendly method for the preparation of chitosan oligomers in H2O2/ILs system. 相似文献
11.
Yusuke Asakuma Yusuke Yamamura Kyuya Nakagawa Kouji Maeda Keisuke Fukui 《Journal of Polymers and the Environment》2011,19(1):209-216
The depolymerization reaction of polyethylene terephthalate (PET) was analyzed on the basis of both experimental data and
numerical data obtained from quantum chemistry calculations. Various alcohols were used as solvents in the search for the
reaction mechanism. The activation energy obtained from the optimized structures of the ground state and the transitional
state was compared with our experimental data. Based on these comparisons, it was found that the formation of rings from alkoxyl
groups and carbonyl carbon atoms at the transitional state is highly important when the ester bonds of PET are broken. Moreover,
the most appropriate alcohol was suggested for the depolymerization reaction. 相似文献
12.
Natural cellulosic fibers are one of the smartest materials for use as reinforcement in polymers possessing a number of applications. Keeping in mind the immense advantages of the natural fibers, in present work synthesis of natural cellulosic fibers reinforced polymer composites through compression molding technique have been reported. Scanning Electron microscopy (SEM), Thermo gravimetric/Differential thermal/Derivative Thermogravimetry (TGA/DTA/DTG), absorption in different solvents, moisture absorbance, water uptake and chemical resistance measurements were used as characterization techniques for evaluating the different behaviour of cellulosic natural fibers reinforced polymer composites. Effect of fiber loading on mechanical properties like tensile strength, flexural strength, compressive strength and wear resistances has also been determined. Reinforcing of the polymer matrix with natural fibers was done in the form of short fiber. Present work indicates that green composites can be successfully fabricated with useful mechanical properties. These composites may be used in secondary structural applications in automotive, housing etc. 相似文献
13.
Kenneth M. Doll Erin L. Walter Rex E. Murray Hong-Sik Hwang 《Journal of Polymers and the Environment》2018,26(9):3670-3676
Organogels are used in a variety of high value applications including the removal of toxic solvents from aqueous environments and the time-controlled release of compounds. One of the most promising gelators is a polyvinyl polymer containing medium chain length carboxylic acids. The existing production of this product requires synthesis of vinyl esters containing medium length carboxylic chains. This starting material must be made from an expensive and low yielding transvinylation reaction, which leaves production of useful vinyl esters and, as a result, the organogels themselves, outside the realm of practical chemistry. We have developed a new, more practical production process and used it to directly synthesize a new polymer. This new process utilizes commercially available polyvinyl acetate and accomplishes the transformation with simple hydrolysis and anhydride addition steps. The new polymers form organogels with chloroform, acetone or toluene with swell ratios up to 30. They also show time-controlled release of crystal violet over a 100 h span. This new production process opens the possibility of producing organogels utilizing agricultural resources. 相似文献
14.
Sustainable Bio-Composites from Renewable Resources: Opportunities and Challenges in the Green Materials World 总被引:28,自引:0,他引:28
Sustainability, industrial ecology, eco-efficiency, and green chemistry are guiding the development of the next generation of materials, products, and processes. Biodegradable plastics and bio-based polymer products based on annually renewable agricultural and biomass feedstock can form the basis for a portfolio of sustainable, eco-efficient products that can compete and capture markets currently dominated by products based exclusively on petroleum feedstock. Natural/Biofiber composites (Bio-Composites) are emerging as a viable alternative to glass fiber reinforced composites especially in automotive and building product applications. The combination of biofibers such as kenaf, hemp, flax, jute, henequen, pineapple leaf fiber, and sisal with polymer matrices from both nonrenewable and renewable resources to produce composite materials that are competitive with synthetic composites requires special attention, i.e., biofiber–matrix interface and novel processing. Natural fiber–reinforced polypropylene composites have attained commercial attraction in automotive industries. Natural fiber—polypropylene or natural fiber—polyester composites are not sufficiently eco-friendly because of the petroleum-based source and the nonbiodegradable nature of the polymer matrix. Using natural fibers with polymers based on renewable resources will allow many environmental issues to be solved. By embedding biofibers with renewable resource–based biopolymers such as cellulosic plastics; polylactides; starch plastics; polyhydroxyalkanoates (bacterial polyesters); and soy-based plastics, the so-called green bio-composites are continuously being developed. 相似文献
15.
Environmental contamination with ionic chromium has been identified as a problem at numerous Superfund and RCRA Corrective Action sites. In many cases, contamination of groundwater to levels above existing standards or criteria may be a potential problem both for direct consumption of groundwater and for transport of mobile forms of chromium to areas such as basements where it can becontacted. In the environment, chromium occurs in two forms: trivalent and hexavalent. The trivalent form is generally immobile and nontoxic; hexavalent chromium is generally mobile and toxic. This article first presents the extent of the chromium problem, reviews the environmental chemistry literature on chromium, and reviews existing treatment technology for chromium immobilization in the nontoxic trivalent state. Finally, we present a case study where immobilization of chromium occurred through natural processes allowing a modified no-action scenario for site remediation. 相似文献
16.
Maria Teresa García Gema Duque Ignacio Gracia Antonio de Lucas Juan F. Rodríguez 《Journal of Material Cycles and Waste Management》2009,11(1):2-5
The amount of extruded polystyrene (XPS) waste has increased in recent years due to the increase of its use in the thermal
insulation of buildings, transport vehicles, and refrigerators, among others. Dissolution with suitable solvents to achieve
a volume reduction of more than 100 times without degradation of polymer chains is one of the cheapest and most efficient
methods of recycling XPS. Several environmentally friendly solvents have been tested as dissolution agents for XPS volume
reduction; the action of these solvents does not produce any degradation of polymer chains. The solubility of the polymer
in such solvents at different temperatures was investigated. The solvent can be easily recycled by distillation, obtaining
a high-quality recycled polymer.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献
17.
Richard A. Brown James G. Mueller Alan G. Seech James K. Henderson John T. Wilson 《补救:环境净化治理成本、技术与工艺杂志》2009,20(1):9-20
While biologically mediated reductive dechlorination continues to be a significant focus of chlorinated solvent remediation, there has been an increased interest in abiotic reductive processes for the remediation of chlorinated solvents. In situ chemical reduction (ISCR) uses zero‐valent iron (ZVI)–based technologies, such as nanoscale iron and bimetallic ZVI, as well as naturally occurring reduced minerals incorporating dual‐valent iron (DVI), such as magnetite, green rust, and iron sulfides that are capable of dechlorinating solvents. A more recent area of development in ISCR has been in combining biological and abiotic processes. There are several ways in which biological and abiotic processes can be combined. First, the interaction between the two may be “causative.” For example, the Air Force Center for Engineering and the Environment's biogeochemical reductive dechlorination (BiRD) technology combines a mulch barrier with hematite and gypsum to create an iron‐sulfide‐based reducing zone. Biodegradation under sulfate‐reducing conditions produces sulfide that combines with the hematite to form iron sulfides. As such, the BiRD technology is “causative”; the biological processes create reducing minerals. The biological generation of other reducing minerals such as magnetite, siderite, and green rust is feasible and is, with magnetite, observed in nature at some petroleum sites. A second type of interaction between abiotic and biotic processes is “synergistic.” For example, biological processes can enhance the activity of reduced metals/minerals. This is the basis of the EHC® ISCR technologies, which combine ZVI with a (slowly) degradable carbon substrate. This combination rapidly creates buffered, strongly reducing conditions, which result in more complete solvent degradation (i.e., direct mineralization). The extent and level of reducing activity commonly observed are much greater when both the carbon substrate and the ZVI are present. When the carbon substrate is expended, the reducing activity due to ZVI alone is much less. The understanding of biogeochemical processes and their impact on abiotic processes is still developing. As that understanding develops, new and improved methods will be created to enhance volatile organic compound destruction. © 2009 Wiley Periodicals, Inc. 相似文献
18.
Rui Galhano dos Santos Noemi F. Acero Sandro Matos Ricardo Carvalho Mário Vale Ana C. Marques João C. Bordado Maria M. Mateus 《Journal of Polymers and the Environment》2018,26(1):91-100
The use of petroleum-derived products should be avoided regarding the principles of green and sustainable chemistry. The work reported herein, is aimed at the liquefaction of pine shavings for the production of an environmentally-friendly polyol suitable to be used in the formulations of sprayable polyurethane foams. The biopolyols were obtained in high yield and were used to replace those derived from fossil sources, to produce more “greener” polyurethane foams and therefore, less dependent on petroleum sources, since the polyol component was substituted by products resulting from biomass liquefaction. The partial and fully exchange of the polyols was accomplished, and the results compared with a reference foam. The foams were afterward, chemical, physical, morphological, and mechanically characterized. The complete replacement of polyether polyol and polyol polyester has presented some similar characteristics as that used as a reference, validating that the path chosen for the development of more sustainable materials is on the right track for the contribution to a cleaner world. 相似文献
19.
Aglaia Theofanoudi Christina Diakaki Eleftheria Katsivela 《Water, Air, & Soil Pollution: Focus》2009,9(1-2):79-88
The paper summarizes the results of a study concerning the operation of industrial plants and their effects to the environment. It also addresses, shortly, the consequences to the quality of human life and proposes potential measures that may contribute to the reduction of the negative environmental impacts. The relatively small organized Industrial Area of Alexandroupolis (Greece) is examined as a case study. In particular, the activities of its major industrial facilities are presented and their emissions to the environment are examined. In addition, the socio-economic aspects of the operation of the Industrial Area are studied. The results of the study showed that the operation of the Industrial Area has specific negative effects in the natural environment of the region and in the quality of life of the residents. Methodological and legislative tools, such as control systems for the environmental pollution, the green chemistry, and the environmental management systems, may be employed to assist the prevention and confrontation of environmental problems. 相似文献
20.
Lobna Daoud Houda Hmani Manel Ben Ali Mouna Jlidi Mamdouh Ben Ali 《Journal of Polymers and the Environment》2018,26(1):23-32
Over a hundred of halophilic/halotolerant microorganisms were screened for alkaline protease production. The bacterium showing the highest enzyme production was characterized and identified as Bacillus halodurans US193 on the basis of 16S rRNA gene analysis. It was alkalophilic, thermophilic and halotolerant since it grew optimally at pH 9.7 and 50?°C with tolerance of up to 125 g NaCl l?1. The alkaline protease was purified 4.9 times with about 40186.1 U/mg as specific activity. It exhibited optimal activity at pH 10, 70?°C and 0.25 M NaCl with perfect stability at wide ranges of pH (6–12), temperatures (30–60?°C) and NaCl concentrations (0–2 M). The serine alkaline protease maintained high stability in the presence of Cu2+, Mg2+, Ba2+ and Ca2+ ions, various organic solvents [50% (v/v)] and ionic and non ionic detergent additives. In addition, it was more compatible with various commercialized detergents than other reported detergent proteases, and was very efficient in blood stain removal. These findings let B. halodurans US193 alkaline protease be an ideal candidate for many industrial processes at harsh conditions, especially as a bio-additive in detergent industry. 相似文献