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qiuqiu3铁虫 (初入文坛)
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[交流]
PEO基固态电解质高温电池想法
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各位同学们好，本人最近在研究PEO基固态电解质，想把PMDA（1,2,4,5 苯四竣酸酐）作为填料和PEO一起用乙腈溶解共混制膜。 想达到的目地是PMDA（热稳定性好）作为骨架负载PEO（导离子性能好）以实现150温度下运行的固态电池，这样的话制备还简单（其它高温电池要用电纺做骨架+PEO）。 不知道我的想法是否可行，同学们有什么建议请指出。 |
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celan
专家顾问 (知名作家)
从事NMR和有机化合物结构鉴定
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小木虫: 金币+0.5, 给个红包，谢谢回帖
小木虫: 金币+0.5, 给个红包，谢谢回帖
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https://www.chem.fsu.edu/chemlab ... _end_group_anal.pdf Determining Number of Moles To determine the number of moles of polymer the analysis method must respond equally to each molecule without regard to its chain length. As the structures given above show, the monomer molecules on the ends of the chain must in some way be different from the chain itself. For a linear polymer (i.e., one in which there are no bonds, called crosslinks, between the chains) every molecule has two end groups, which may be identical, as in PEG, or different, as in Dacron. (For polymers such as PVC and polystyrene the identities of R and R’ depend on the choice of reagent used to initiate the polymerization reaction.) Thus, if the end groups can be analyzed, the number of polymer molecules may be calculated using simple stoichiometric relationships. This method for determining Mn is called end group analysis. Figure 2. Reaction of PMDA with PEG to produce ester Some Specifics The ends of PEG are alcohol groups, which may be analyzed by a reaction known as esterification. In an esterification the -OH reacts with an organic acid, or, more commonly, with a more reactive derivative of the acid. In this experiment the anhydride of 1,2,4,5 benzenetetracarboxylic acid, known commonly as pyromellitic dianhydride, or PMDA for short, will be used. The reaction with PEG is shown in Fig. 2. The reaction must be conducted in a nonaqueous solvent, and, because of its low volatility and desirable solvating properties, N,N-dimethyl formamide, DMF, is a good choice. A catalyst is also required, and in many esterification procedures pyridine, a rather foul-smelling organic base, is used. However, for the reaction of alcohols with PMDA it has been found that imidazole, IMDA, a very soluble solid with no odor, has at least equal catalyzing power. The formulas of DMF and IMDA are shown below. The analysis involves an indirect titration procedure. An excess of PMDA is mixed with the weighed PEG sample, and the catalyst is added. After the reaction is complete (at least one-half hour reaction time), water is added to convert the unreacted anhydride groups to the acid form, and the acid is titrated with standard NaOH. The equations in Fig. 3 show that each ester linkage to a PEG end group replaces one of the four |
22楼2025-06-26 10:02:37
2楼2025-06-19 16:34:49
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qiuqiu3(金币+1): 谢谢参与
qiuqiu3(金币+1): 谢谢参与
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4楼2025-06-19 17:04:30
9楼2025-06-20 08:11:19
