共查询到19条相似文献,搜索用时 62 毫秒
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以桐油酸(ESA)和聚乙二醇(PEG)为原料,合成了一种新型的两亲性聚合物聚乙二醇-桐油酸酯(PEG-ESA)。通过红外光谱、质谱和核磁共振光谱法对产物进行表征。利用表面张力法和荧光探针法探究聚合物溶液相关性质,测定不同条件下两亲性聚合物胶束的zeta(ζ)电位和粒径。实验结果表明:利用表面张力法测得PEG-ESA临界胶束浓度(CMC)为1.1×10-5g/L;芘可以增溶于聚合物胶束中;在一定条件下聚合物的胶束可以稳定存在且粒径可达纳米级,为其用于药物缓释提供实验依据。 相似文献
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以1,2-二硬脂酸甘油酯为原料,与三氯氧磷及乙醇胺反应合成1,2-二硬脂酰甘油磷酰乙醇胺(DSPE);再以聚乙二醇2000 (PEG2000)为原料,通过磺酰化、叠氮化反应合成叠氮基聚乙二醇2000(N_3-PEG2000); DSPE与N_3-PEG2000在N,N-羰基二咪唑(CDI)作用下生成叠氮基聚乙二醇2000-1,2-二硬脂酰甘油磷酰乙醇胺(N_3-PEG2000-DSPE);最后通过催化氢化制备氨基聚乙二醇2000-1,2-二硬脂酰甘油磷酰乙醇胺(NH_2-PEG2000-DSPE),其结构经过IR、MS及~1H NMR等确证。 相似文献
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以单甲氧基聚乙二醇(mPEG)和Fmoc-Lys(Boc)-OH(1)为主要原料,经过羧基苄酯化、侧链Boc脱除、ε-氨基丁二酸酐修饰得到功能化的赖氨酸化合物N-α-芴甲氧羰基-N-ε-(γ-氧代丁酸)-L-赖氨酸苄酯(4);1和4分别与mPEG在偶联剂D IC/HOB t的作用下联接,最终分别实现了赖氨酸主链和侧链的mPEG定点修饰,合成了新型的N-α-芴甲氧羰基-N-ε-(γ-氧代丁酸聚乙二醇酯)-L-赖氨酸苄酯(5,总收率52.6%)和N-ε-叔丁氧羰基-N-α-芴甲氧羰基-L-赖氨酸聚乙二醇酯(6,收率93.7%),其结构经1H NMR,IR和MS表征。 相似文献
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马来酸二丁酯的杂多酸催化合成及动力学研究 总被引:8,自引:0,他引:8
考察了无机酸(如硫酸、盐酸)和新型杂多酸(如磷钨酸、硅钨酸)为催化剂,催化合成马来酸二丁酯的反应。结果表明,对于两类催化剂,其酯收率相当;确定了杂多酸催化合成马来酸二丁酯的反应级数为二级;PW12和SiW12杂多酸催化剂的表观活化能分别为60.4和57.0kJ/mol。 相似文献
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一种合成端羧基聚乙二醇单甲醚的新方法 总被引:1,自引:0,他引:1
以聚乙二醇单甲醚和丙烯腈为原料,在水相中合成了一端为羧基的聚乙二醇单甲醚,其结构经1H NMR和IR确证。讨论了反应时间、反应温度、溶剂和惰性气氛对反应的影响。 相似文献
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本文报道了聚苯乙烯固载聚乙二醇三相催化剂在卡宾的生成、酯化、假性紫罗兰酮、二茂铁、芳氧乙酸、对硝基茴香醇的合成和C、N-烃基化等反应中的应用,并对其催化机理进行了探讨. 相似文献
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N-羟基丁二酰亚胺的合成 总被引:1,自引:0,他引:1
N 羟基丁二酰亚胺是一种重要的有机中间体 ,可用于多肽合成中的外消旋抑制剂[1 ] 和一些抗菌素的合成 ,也可用于制备活性酯[1~ 3] 。近年来在生物活性分子的合成[4] 及乙烯型聚合物的分子量控制[5]上也获得了广泛的应用。N 羟基丁二酰亚胺的合成早已有报道[6] ,但收率较低。Hoppe Seyler′s[7] 以水和二氧六环作为丁二酸酐与羟胺反应的混合溶剂 ,加热环合脱水 ,然后用乙酸乙酯反复提取 ,虽可得到75 %收率 ,但产物中往往混有 5 %~ 1 0 %的丁二酸难以除去 ,若要获得商品级产物 ,后处理过程复杂 ,且要损失 1 5 %~ 2 0 %的产物[8] 。Cherut… 相似文献
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Bhajendra N. Barman Donald H. ChampionStephen L. Sjoberg 《Journal of chromatography. A》2009,1216(40):6816-6823
Quantitative determination of polyethylene glycol (PEG) impurities in two monofunctional polyglycol types, PEG methyl ether (M-PEG) and PEG vinyl ether (V-PEG), has been carried out by reversed-phase liquid chromatography with evaporative light scattering detection (ELSD). In addition to optimizing the resolution between PEG and monofunctional PEG peaks, the major focus has been to determine the molecular weights of PEG impurities in M-PEG and V-PEG of diverse molecular weights. The latter is achieved by examining liquid chromatography–mass spectrometry (LC–MS) mass spectra of both monofunctional PEG and PEG in several cases, and matching peak retention times with those of available PEG standards for all M-PEG and V-PEG sample types. This information is helpful in selecting the appropriate PEG standard to determine PEG content in each sample type. ELSD response factors for various PEG standards have also been compared. It has been found that PEG standards with molecular weights from 1000 Da to 8000 Da show responses that are within 10% of each other. However, a low molecular weight PEG such as PEG 400, provides approximately 30% less response compared to its higher molecular weight counterparts. 相似文献
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X. Han Y. H. Hu Z. K. Lin S. F. Li F. Q. Zhao Z. R. Liu J. H. Yi L. Y. Zhang X. N. Ren 《Journal of Thermal Analysis and Calorimetry》2008,93(3):927-932
Effects of fullerenes including FS, EFS and pure C60 on thermal behaviors of polyethylene glycol (PEG) have been studied by employing thermogravimetry-differential thermogravimetry
(TG-DTG), differential scanning calorimeter (DSC) and off-line furnace-type pyrolysis-gas chromatography/mass spectrometry
(Py-GC/MS). The products were collected by Cambridge filter pad which was widely used in analyzing the combustion products
of cigarette. The results showed that the addition of fullerenes obviously restrained the thermal decomposition of PEG. The
initial decomposition temperatures (IDT) and maximum decomposition peak temperatures (MDT) were evidently postponed by the
addition of fullerenes. Pyrolysis products with one or two hydroxyl end groups obviously increased with the addition of 10%
C60. The reasons of the changes were discussed from the aspects of reaction mechanisms. 相似文献
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Synthesis and characterization of a nano‐hydroxyapatite/chitosan/polyethylene glycol nanocomposite for bone tissue engineering 下载免费PDF全文
Mohammad Shakir Reshma Jolly Mohd Shoeb Khan Noor‐e Iram Tarun Kumar Sharma Saud Ibrahim Al‐Resayes 《先进技术聚合物》2015,26(1):41-48
A novel nanocomposite involving nano‐hydroxyapatite/chitosan/polyethylene glycol (n‐HAP/CS/PEG) has been successfully synthesized via co‐precipitation approach at room temperature. The purpose to synthesize such nanocomposite is to search for an ideal analogue which may mimick the composition of natural bone for bone tissue engineering with respect to suitable biocompatibility, cytotoxicity and mechanical properties. The FTIR spectra of n‐HAP/CS and n‐HAP/CS/PEG scaffolds indicated significant intermolecular interaction between the various components of both the nanocomposites. The results of XRD, TEM and TGA/DTA suggested that the crystallinity and thermal stability of the n‐HAP/CS/PEG scaffold have decreased and increased respectively, relative to n‐HAP/CS scaffold. The comparison of SEM images of both the scaffolds indicated that the incorporation of PEG influenced the surface morphology while a better in‐vitro bioactivity has been observed in n‐HAP/CS/PEG than in n‐HAP/CS based on SBF study, referring a greater possibility for making direct bond to living bone if implanted. Furthermore, MTT assay revealed superior non‐toxic nature of n‐HAP/CS/PEG to murine fibroblast L929 cells as compared to n‐HAP/CS. The comparative swelling studies of n‐HAP/CS/PEG and n‐HAP/CS scaffolds revealed a better swelling rate for n‐HAP/CS/PEG. Also n‐HAP/CS/PEG showed higher mechanical strength relative to n‐HAP/CS supportive of bone tissue ingrowths. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献