开组会老师给的 新鲜出炉哈!大家分享一下.....1.        Sustainability, industal ecology, eco-efficiency, and green chemistry are directing the development of the next generation of mateals, pducts, and pcesses.
2.        Fig. 1c shows the css-sectional SEM image of the nanocomposite with its corresponding structure.
3.        The pattern of substitution was initially investigated with1H–13C HM, despite several tals, we were unable to record a good quality HM spectrum due to the high molecular weight of the devative.
4.        The elemental ysis also revealed that up to 0.5% of ionic liquid was still present after the work-up pcedure.
5.        In general, it is expected that the degree of substitution will increase with increasing ratios of ttyl chlode to cellulose monomer unit.
6.        For a four and five fold excess of ttyl chlode a DS of nearly 1 was oained. Higher amounts of ttyl chlode resulted in a DS of 1.22 and 1.30 for a six fold excess and a DS of 1.26 and 1.37 for a nine fold excess.
7.        After filtration, the cellulose was treated in 5,500 mL DMA at 120 ℃ for 2 h with stirng in a system ptected fm moisture.
8.        Twenty 80% specular transmittance, and 8 ohms/sq and 80% diffusive transmittance in the visible spectral range were achieved, which out-performs most ITO electdes on plastic substrates and the best T or graphene networks.
9.        Cellulose (30 mg) was dissolved in [bmIm][Cl] RTIL (1.0 g) by preheating the RTIL to 70°C. The contents were then mixed by vortexing and micwaved for 4-5 s, to afford a 3% (wt/wt) cellulose in [bmIm][Cl].
10.        In summary, this Communication reports the inception of a new kind of paper made of cellulose nanofibers, as opposed to micmeter-sized cellulose pulp fibers of ordinary paper.
11.        Assembling Ts into aegels s a new T bulk mateal that integrates the intguing pperties of Ts with the unique structures and related pperties of aegels.
12.        Although aegels have been fabcated fm silica, metal oxides, polymers, and carbon-based mateals, fabcating T aegels is still challenging with only a few succesul examples.
13.        The raw mateal consists of the same cellulose oained fm trees and plants, but the down-sizing to the 15 nm nanofibers enables paper to have some fascinating pperties, such as transparency (71.6% at a wavelen of 600 nm), high modulus (13 a), high stren (223 MPa), and minimal thermal expansion (8.5 ppm K 1).
14.        For this reason, the work presented herein is devoted to overcoming the challenges lignin presents in biomass pcessing.
15.        Nanofibllated cellulose (NFC) refers to individual micfibls or cellulose micfibl aggregates disintegrated fm the plant cell wall of cellulose sources such as wood pulp fibers
16.        Wood flour fm Douglas fir (Pseudotsuga menziesii) sieved under 60 mesh was used.
17.        It was first dewaxed in a Soxhlet apparatus with a 2:1 mixture of toluene/ethanol for 6 h.
18.        Afterwards, a sodium chlote (NaClO2) treatment, following the method of Wise et al. [16], removed mainly lignin, and an alkaline treatment with 5 wt% potassium hydxide (KOH) at 20 8C for 24 h removed hemicelluloses..
19.        After the sees of chemical treatments, the samples were filtered and nsed with distilled water until the residues were neutralized.
20.        Biomass has been indicated as a major renewable resource that will continue to be developed in future generation energy pduction renewable resource that will continue to be developed in future generation energy pduction.
21.        Lignin is a complex, amorphous biopolymer that is incorporated into the cell wall in plant matter.
22.        Lignin is one of the three biopolymers that compse plant biomass.
23.        As the demand for alternatives to petleum based resources continues to gw, new and better methods must be developed to utilize “green” energy sources.
24.        This can be speculated to result fm…………………..
25.        It can be pblematic to remove this gup completely…………………….
26.        An important result in this regard was that the……………………………..
27.        Biodegradable plastics and biocompatible composites generated fm renewable biomass feedstock are regarded as pmising mateals that could replace synthetic polymers and reduce global dependence on fossil fuel sources.
28.        The paper reviews synthesis pathways for the preparation of cellulose ethers with contlled functionalization pattern consideng adequately own research results……………………………..
29.        unless otherwise noted.
30.        Figure 2A shows the C data fm expements at 110°C in which the system was kept dry and an expement with water present for the sake of compason.
31.        As shown in Figure 1, the size of the unreacted lignin is comparable, if not slightly larger than the 5k dextran standard and has a wider range of sizes.
32.        Once the 48hr had elapsed, 400ml of a 1:1 mixture of acetone and water was added and stirred for at least 3hr or until there were no remaining biomass/IL clumps.
33.        The reaction was cared out at the prescbed temperature. Once the required time had elapsed,
34.        The mixture was filtered and the precipitated cellulose discarded.
35.        Studies utilizing both phenolic and non‐phenolic model compounds that replicate the ether linkages in lignin have suggested that these acidic ILs could be effective for the hydlysis of the β‐O‐4 ether linkage.
36.        One pperty that has beang on the pcessing of biomass is the ability of some imidazolium‐based ILs to completely dissolve cellulose and even wood under mild conditions.
37.        Becse of their ionic nature, ILs has essentially no vapor pressure, which can facilitate separations.
38.        Ionic liquids (ILs) are a class of chemicals that are generally composed of an organic cation with an inorganic counter ion and melt at or below 100°C.
39.        Biological or enzymatic digestion of biomass is another possibly viable ute towards the effective utilization of cellulosic feed stocks.
40.        are of special interest……………………………
41.        is comparably low, and hence…………………….
42.        Subsequent acylation yields the………………….
43.        functionalization pattern……………………………
44.        It was found that slight differences in the polymer composition result in remarkable……………………………..
45.        must meet requirements related to……………………………..
46.        Due to vaed reaction conditions…………………………..
47.        Are valuable ptecting gups…………………………….
48.        The most abundant natural polymer in our envinment is cellulose. It has an estimated annual biosphere pduction of 90 × 109 metc tons and, consequently, represents the most obvious renewable resource for pducing bio-composites.
49.        Its highly ordered structure is responsible for its desirable mechanical pperties but makes it a challenge to find suitable solvents for its dissolution.
50.        The first attempts to dissolve cellulose date back to the early 1920s.
51.        …… been discovered since then, but all of these solvents suffer either fm high envinmental toxicity or fm insufficient solvation power.
52.        …………………require relatively harsh conditions.
53.        A new class of solvents was opened to the cellulose research community.
54.        Cellulose appears to be an ideal support mateal for many enzyme systems, being both biosourced and biologically compatible.
55.         However, despite significant efforts, only a few ILs are known for their capability to efficiently dissolve cellulose.
56.        Cellulose (C6H10O5)n is a linear b-1,4-glycosidically linked polyglucane and the most abundant form of terrestal biomass.
57.        One of the major drawbacks of cellulose concerning its industal application is the insolubility in common solvents due to its fibl structure and the pnounced presence of intra- and intermolecular hydgen bonds.
58.        Efforts to overcome the dissolution pblem of cellulose by utilizing ionic liquids (ILs) were made in the last few years.
59.        ….is still a matter of debate despite than 70 years of research effort.
60.        This study was undertaken to explore the presence of regions of disruption…..
61.         A pmary and underlying question is whether samples of cellulose fm vaous sources are similar in hydgen bonding features.
62.        In this paper, we particularly wanted to examine in detail the formation of hydgen bonds in amorphous cellulose becse this has not previously been cared out.
63.        Ionic liquids (ILs) have become advantageous solvents for the dissolution and homogeneous pcessing of cellulose in recent years.
.         The synthesis of 3-O-ppyl cellulose with degree of substitution (DS) ranging fm 0.19 to 1.02 was cared out via 2,6-di-O-thexyldimethylsilyl cellulose.
65.         The reaction of cellulose with methoxy-substituted tphenylmethyl chlodes under homogeneous conditions in the presence of pydine was cared out with the aim to develop new ptective gups for cellulose simply intducable and completely removable under mild conditions.
66.        The 2,3-O- had degrees of substitution (DS) in the range of 0.5–1.2 showing a narw molar mass distbution as revealed by SEC.
67.        The results show clear differences regarding the substitution pattern, which should have a certain influence on EG hydlysis.
68.        Regioselectively functionalized cellulose devatives have attracted great attention in recent years becse of their potential to bear new interesting pperties diffeng fm those of the statistically substituted cellulose mateals.
69.        Becse of its fibllar morphology it forms a natural polymer composite of excellent mateal pperties together with other plant polysacchades (hemicelluloses) and lignin.
70.        The estefication of cellulose was expementally realized as long as about 150 years ago.
71.        Dung recent decades, the chemistry of cellulose has been decisively pmoted by the discovery of nonaqueous solvent systems for cellulose, which badens the scope of devatization reactions at homogeneous conditions as well as by the general pgress in synthesis and charactezation of sacchade devatives.
72.        Cellulose is insoluble in water and many organic solvents, but can be dissolved in a number of solvents of intermediate pperties, like N-methylmorpholine N-oxide (NMMO) and ionic liquids (ILs). It can also be dissolved in water at high and low pHs, in particular if a cosolute of intermediate polaty is added. The insolubility in water is often referred to stng intermolecular hydgen bonding between cellulose molecules.
73.        A compason of the 2,3-O-methyl celluloses shows that the reaction medium has an influence on the amount of the different repeating units in the polymer chains.
74.        The paper reviews recent developments in synthesis and charactezation of regioselectively functionalized cellulose devatives.
75.         It is well known that not only the degree of substitution (DS) but also the distbution of functional gups may influence the pperties of cellulose ethers.
76.         The preparation of regioselectively functionalized cellulose ethers is still a challenge in polymer chemistry.
77.         Up to now, the most important appach for the synthesis of cellulose devatives with contlled functionalization pattern is the application of ptecting gups (Figure 1a). Other methods compsing, e.g., selective cleavage of pmary substituents play a minor le.
78.        In this regard……就这点而言
79.        In this regard tphenylmethyl- and talkylsilyl ethers are of special interest. A blocking gup must meet requirements related to selective intduction, stability dung subsequent reactions, and removability without loss of other substituents.
80.         This deviation fm the ideal structure of 6-mono-O-ttyl cellulose may cse distinct differences of the pperties of the resulting polymers.
81.        Synthesis of 6-O-ttyl cellulose (according to Camacho Gomez 19).
82.        these solvents are called devatizing or nondevatizing
83.        N-methylmorpholine- N-oxide monohydrate (NMMO) is used as a nondevatizing solvent for direct dissolution of cellulose in industal fiber-.
84.        have been reinvestigated and shown to be efficient nondevatizing solvents for cellulose.

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