邻苯二亚胺纤维素的合成及性质

邻苯二亚胺纤维素的合成及性质叶君熊犍梁文芷（华南理工大学轻化工研究所广州５１０６４１）关键词邻苯二亚胺纤维素荧光合成中图分类号Ｏ６３６．１１，ＴＱ３５２．９纤维素化学反应是纤维素化学改性和功能材料合成的基础。以往纤维素化学反应的研究工作大多集中于其分...     

pH值对邻苯二亚胺纤维素的制备及荧光性能的影响

制备了席夫碱（Ｓｃｈｉｆｆ’ｓ ｂａｓｅ）邻苯二亚胺纤维素（ＰＤＩＭＣ），考查ｐＨ值对制备反应和产物荧光性能的影响。结果表明：氧化度为１００％的二醛纤维素在ｐＨ＝７￣１３、室温下、反应３０ｈ生成的邻苯二亚胺纤维素，具有强较的荧光性能，熔点４１０ｋ，分解温度为５７８Ｋ；ＰＤＩＭＣ水溶液在ＰＨ＝７．６，浓度为７．６×１０＾－４ｇ／ｍＬ，２０℃时，Ｅｘ＝４７０ｎｍ，Ｅｍ＝５５５ｎｍ处荧光最强。     

4-(2,6-二甲基苯氧基)邻苯二腈的合成与物理光学研究

合成出一种具有荧光性质的小分子有机分子,用1HNMR,IR和元素分析进行了表征.研究了该有机分子的荧光性质,在浓度为1×10-3mol/L时,激发波长为340nm,发射波长是459nm;浓度对发射光谱的峰位和强度有影响.     

邻苯二甲醛-β-巯基乙醇组合试剂可视化荧光检测多巴胺

研究发现,在碱性条件下,邻苯二甲醛和β-巯基乙醇组合试剂可与多巴胺发生化学反应生成异吲哚类化合物。当用340 nm光激发时产生462 nm的荧光,且荧光强度与多巴胺含量呈良好的线性关系,从而建立了一种可视化荧光检测多巴胺的新方法。在pH 9.8的H3BO3-NaOH缓冲条件下,检测的线性范围为5.2×10-8~1.7×10-5mol/L,相关系数为0.9993,检出限(3σ)为4.1×10-8mol/L。对7.0×10-6mol/L的多巴胺进行11次平行测定,其相对标准偏差为1.4%。方法用于盐酸多巴胺注射液含量的分析,平均加标回收率为97.7%。以波长为365 nm紫外灯激发多巴胺样品,可实现多巴胺可视化半定量检测。     

4-氨基邻苯二甲酰亚胺衍生物作为荧光探针的应用

介绍了近年来4-氨基邻苯二甲酰亚胺(AP)类荧光探针在主-客体化学、金属离子测定、溶剂化动力学及各种有序分子聚集体(如胶束、反胶束)性质研究方面的进展。     

取代邻苯二腈的合成

在室温条件下合成了一系列芳氧基邻苯二腈化合物,应用无素分析、1HNMR、IR确定了它们的结构,讨论了不同取代基对反应的影响.结果表明,酚的芳环上有推电子基时反应容易进行;酚的芳环上有拉电子基时反应慢或不反应.     

基于邻苯二甲醛-NH_3-Na_2SO_3反应的固相荧光分析方法测定水样中的氨氮

基于邻苯二甲醛(OPA)-NH3-Na2SO3体系的荧光反应,以滤纸为固相载体,建立了检测水样中氨氮的固相荧光分析新方法。对滤纸的浸泡时间、反应液的p H值、反应时间等实验参数进行了优化,优化结果为:滤纸的最佳浸泡时间为4 h以上;反应液的适宜p H值为11.5~13.0;反应平衡时间为165 min。在优化实验条件下,方法的线性范围为2.00~12.0μmol/L;检出限为0.746μmol/L;泉水和河水的基底加标回收率为89.6%~101.6%。采用该法成功测定了14个河水水样,与靛酚蓝分光光度法测定结果比较,无显著差异。     

N─苯基邻苯二甲酰亚胺和N─对甲苯基邻苯二甲酰亚胺的晶体和分子结构

报道一种新类型的有机电子晶体Ｎ－苯基邻苯二甲酰亚胺（１）（Ｃ＿（１４）Ｈ＿９ＮＯ＿２）和Ｎ－对甲苯基邻苯二甲酰亚胺（２）（Ｃ＿（１５）Ｈ＿（１１）ＮＯ＿２）的晶体和分子结构，（１）属正交晶系，空间群为Ｐｃａｂ，ａ＝７．６４９（４），ｂ＝１１．６５９（２），ｃ＝２３．７３９（３）Ａ，Ｖ＝２１１７．０Ａ￣３，Ｚ＝８，Ｄ＿ｃ＝１．４０１ｇ／ｃｍ￣３，Ｍ＿ｒ＝２２３．２３，μ＝０．８８５ｃｍ￣（－１），最终偏离因子Ｒ＝０．０５３，Ｒ＿ω＝０．０４８；（２）属正交晶系，空间群为Ｐｎａ２＿１，ａ＝７．６２４（２），ｂ＝１１．２３７（１），ｃ＝１３．８５６（２）Ａ，Ｖ＝１１８７．０　Ａ３，Ｚ＝４，Ｄ＿ｃ＝１．３２８ｇ／ｃｍ￣３，Ｍｒ＝２３７．２６，μ＝２．７６４ｃｍ－１，最终偏离因子Ｒ＝０．０３６，Ｒ＿ω＝０．０３２。晶体结构测定结果表明，邻苯二甲酰亚胺的内酰亚胺碳、氮、氧原子与其苯并环共平面。化合物（２）中的甲基碳原子与取代基苯环共平面，苯并酰亚胺平面与取代苯环平面间的夹角分别为５８．４°（化合物１）和５６．２°（化合物２）。     

N─苯基邻苯二甲酰亚胺和N─对甲苯基邻苯二甲酰亚胺的晶体和分子结构

报道一种新类型的有机电子晶体Ｎ－苯基邻苯二甲酰亚胺（１）（Ｃ＿（１４）Ｈ＿９ＮＯ＿２）和Ｎ－对甲苯基邻苯二甲酰亚胺（２）（Ｃ＿（１５）Ｈ＿（１１）ＮＯ＿２）的晶体和分子结构，（１）属正交晶系，空间群为Ｐｃａｂ，ａ＝７．６４９（４），ｂ＝１１．６５９（２），ｃ＝２３．７３９（３）Ａ，Ｖ＝２１１７．０Ａ￣３，Ｚ＝８，Ｄ＿ｃ＝１．４０１ｇ／ｃｍ￣３，Ｍ＿ｒ＝２２３．２３，μ＝０．８８５ｃｍ￣（－１），最终偏离因子Ｒ＝０．０５３，Ｒ＿ω＝０．０４８；（２）属正交晶系，空间群为Ｐｎａ２＿１，ａ＝７．６２４（２），ｂ＝１１．２３７（１），ｃ＝１３．８５６（２）Ａ，Ｖ＝１１８７．０　Ａ３，Ｚ＝４，Ｄ＿ｃ＝１．３２８ｇ／ｃｍ￣３，Ｍｒ＝２３７．２６，μ＝２．７６４ｃｍ－１，最终偏离因子Ｒ＝０．０３６，Ｒ＿ω＝０．０３２。晶体结构测定结果表明，邻苯二甲酰亚胺的内酰亚胺碳、氮、氧原子与其苯并环共平面。化合物（２）中的甲基碳原子与取代基苯环共平面，苯并酰亚胺平面与取代苯环平面间的夹角分别为５８．４°（化合物１）和５６．２°（化合物２）。     

壳聚糖在稀溶液中的聚集行为

壳聚糖在稀溶液中的聚集行为;荧光探针;荧光偏振;聚集行为     

CMC系列高分子表面活性剂的胶束形态

高分子表面活性剂分子量高 ,分子中兼具亲水和疏水链段 ,在选择性溶剂水中同小分子表面活性剂一样 ,可形成疏水链段为核心、亲水链段为外壳的胶束结构 ,但高分子量又使其表现出许多不同于低分子表面活性剂的形态特征 ,如胶束的多种形态、尺寸分布多分散性等等 ,而这些形态特征对高分子表面活性剂的界面活性、增粘、乳化等性能有决定性的影响．结构规整的嵌段或接枝共聚物在选择性溶剂中的分子聚集形态已有研究 ［１,２］,亲水亲油性的高分子表面活性剂在水溶液中由于结构复杂、水溶液中氢键作用及静电作用力等因素造成的困难 ,因而研究较少…     

Dissolution of Cellulose in Aqueous NaOH Solutions

Dissolution of a number of cellulose samples in aqueous NaOH was investigated with respect to the influence of molecular weight, crystalline form and the degree of crystallinity of the source samples. A procedure for dissolving microcrystalline cellulose was developed and optimized, and then applied to other cellulose samples of different crystalline forms, crystallinity indices and molecular weights. The optimum conditions involved swelling cellulose in 8–9 wt % NaOH and then freezing it into a solid mass by holding it at –20°C. This was followed by thawing the frozen mass at room temperature and diluting with water to 5% NaOH. All samples prepared from microcrystalline cellulose were completely dissolved in the NaOH solution by this procedure. All regenerated celluloses having either cellulose II or an amorphous structure prepared from linter cellulose and kraft pulps were also essentially dissolved in the aqueous NaOH by this process. The original linter cellulose, its mercerized form and cellulose III samples prepared from it had limited solubility values of only 26–37%, when the same procedure was applied. The differences in the solubility of the celluloses investigated have been interpreted in terms of the degrees to which some long-range orders present in solid cellulose samples have been disrupted in the course of pre- treatments.     

Novel Fibers Prepared from Cellulose in NaOH/Urea Aqueous Solution

Summary: Novel regenerated cellulose fibers have been successfully spun from the cellulose dope in NaOH/urea aqueous solution, which could rapidly dissolve cellulose. The fibers possess circular cross‐sections as well as relatively high molecular weight, and a crystallinity index with cellulose II family crystal structure, leading to good mechanical properties. This technology is simple, cheap, and environmentally friendly, promising to substitute for viscose rayon production having hazardous byproducts.

SEM micrograph of the cross‐section of the novel cellulose fibers generated here.     

Homogenous Carboxymethylation of Cellulose in the New Alkaline Solvent LiOH/Urea Aqueous Solution

In this work, the carboxymethylation of cellulose in a new alkaline cellulose solvent, LiOH/urea aqueous solution, was investigated. Carboxymethyl cellulose (CMC) samples were characterized with FT-IR, NMR, HPLC, and viscosity measurements. Water-soluble CMC with DS = 0.36∼0.65 was prepared, from both Avicel cellulose and cotton linters in the LiOH/urea system. The total DS of CMC could be controlled by varying the molar ratio of reagents and the reaction temperature. The results from structure analysis by HPLC after complete depolymerization showed that the mole fractions of the different carboxymethylated repeating units as well as those of unmodified glucose follow a simple statistic pattern. A distribution of the carboxymethyl groups of the AGU was determined to be in the order O-6 > O-2 > O-3 position at the level.     

水溶液中金属增强荧光的研究进展

本文综述了水溶液中金属增强荧光的研究进展,重点阐明如何通过控制荧光物质与金属纳米粒子表面的距离,实现水溶液中的金属增强荧光。荧光物质与金属纳米粒子表面的距离主要通过有机分子和无机分子Si O2层控制,只有当距离合适才能达到最大的金属增强荧光。金属增强荧光提高了荧光检测的灵敏度,扩大了荧光技术的应用范围,已广泛应用到DNA、蛋白质检测、生物标记、生物成像和免疫分析中。     

用荧光方法研究端基为芘的聚苯乙烯在溶液中的聚集行为

利用原子转移自由基聚合（ATRP） 方法合成了窄分布的端基含有芘或萘的聚 苯乙烯（Py-PS和Na-PS）。研究了Py-PS在四氢呋喃（THF）溶液中的荧光发射光谱 随加水量的变化。结果表明,加水初期随着加水量的增加,对应于芘的单体荧光发 射峰强度（I_M）增加,当水加到一定量时,观察到由芘形成的激基缔合物（ excimer）的荧光光谱峰,其强度（I_E）随加水量的增加而进一步增强,而I_M下 降,直至体系产生宏观的相分离,此时I_M和I_E均不变。对这一结果从分子水平上 进行了讨论,并通过I_E/I_M与I_1/I_3随加水量的变化得到了不同浓度下Py-PS在 THF中聚集的临界加水量。另外,我们也用非辐射能量转移（NRET）的方法研究了 Py-PS混合溶液的聚集。这些结果对于进一步研究含聚苯乙烯链段的嵌段共聚物在 溶液中的聚集有重要意义。     

Metal‐Enhanced Fluorescence of CdTe Nanocrystals in Aqueous Solution

Metal‐enhanced fluorescence of semiconductor nanocrystals (NCs) is investigated. There is very little attention paid to the metal‐enhanced fluorescence in aqueous solution, which has great potential applications in bioscience. In this work, we directly observe metal‐enhanced fluorescence of CdTe NC solution by simply mixing CdTe NCs and Au nanoparticles, both of which are negatively charged. In order to study this kind of photoluminescence enhancement in aqueous solutions, we propose a calibration method, which takes into account the light attenuation in solutions. After consideration of the light weakening in transmission, the maximal PL enhancement is about 3 times as large as the ones without Au NPs. Some factors related to the enhanced magnitude of fluorescence, for instance, the concentration and the molar feed ratio of CdTe NCs and Au NPs, are studied in detail. Furthermore, the decreased lifetimes of CdTe NCs induced by Au NPs are also obtained, which are in accord with the enhancement of the photoluminescence.