烷基酚聚氧乙烯醚非离子表面活性剂的电子电离质谱分析法的研究

烷基酚聚氧乙烯醚为同系物之混合物,且难以分离。现采用其混合物直接进样法,研究了该化合物的电子电离质谐(EI/MS)。适当地控制进样温度,可获得反映其结构特征的EI/MS数据,以确定分子结构中烷基链的大小及其分子量的分布范围,即聚氧乙烯醚的缩合度。     

全氟辛烷磺酸与载脂蛋白AⅠ非共价键复合物的质谱分析实验探究

本文采用电喷雾质谱(ESI-MS)方法,分析研究了载脂蛋白AⅠ(Apo AⅠ)、全氟辛烷磺酸(PFOS)与Apo AⅠ结合的最佳实验条件和仪器参数。探讨了电喷雾离子源温度和碎裂电压对Apo AⅠ蛋白质多电荷质谱峰信号的影响,以及在最佳仪器条件下(电喷雾离子源温度为200℃,碎裂电压为175 V),获得了PFOS-Apo AⅠ形成的蛋白质复合物质谱谱图。在该条件下,Apo AⅠ最多能与PFOS形成化学计量比为1:4的蛋白质复合物。     

支链化脂肪醇聚氧乙烯醚的结构和性能研究

采用气相色谱／质谱（GC／MS）联用技术分析了Basf,Shell等公司商品化的支链化脂肪醇聚氧乙烯醚的碳链分布、结构和支链组成；考察了不同碳链、支链和EO分布的脂肪醇聚氧乙烯醚的物化性质，如泡沫、润湿力等，并研究了其和阴离子复配时的一些性能，如去污力、泡沫和润湿力等指标。结果表明，支链程度高的产品如XP、XL等系列产品的润湿能力明显高出其他支链化程度低的产品。但支链化程度和产品的一些性能如去污能力和泡沫等并没有规律性的关系，而是碳链分布、EO分布和支链等多因素的综合影响。     

二维色谱测定石脑油中微量含氧化合物

文章采用二维气相色谱测定石脑油及乙烯裂解装置原料中微量含氧化物的含量。二维中心切割(heart-cutting)技术样品中的氧化物组份在非极性柱上预分离后,被切割到极性柱上继续分离,氢火焰离子化检测器检测含氧化合物含量。该方法操作简单,分析时间在20 min以内,重复测定结果的相对标准偏差小于1.8%,方法准确可靠。     

烷基酚聚氧乙烯醚亲水链长度对水煤浆性能的影响

以烷基酚聚氧乙烯醚(APEO)为水煤浆添加剂,在不添加稳定剂的情况下,采用粘度分析法研究了APEO亲水链长度对5种不同煤所制得水煤浆的分散降粘作用的影响. 结果表明,当APEO的亲水亲油平衡值为18.5±0.4,即APEO的聚氧乙烯加成数(EO数)为60~100时,所得水煤浆浆体的表观粘度出现最低值,再增加或降低EO数,成浆性能下降. 不同APEO对应的最佳EO数不同,烷基链较短的对应较短的亲水链,烷基链较长的对应较长的亲水链. 烷基碳原子数为7, 9, 12, 14, 16, 18时,对应的最佳EO数分别为60, 60, 70, 80, 90和100.     

中心切割气相色谱法测定液化石油气中甲缩醛等9种含氧化合物

采用微板流路控制Deans Switch中心切割技术、双火焰离子化检测器的双柱气相色谱系统,建立了测定液化石油气中甲缩醛等多种含氧化合物的方法。在优化的色谱条件下,将适量试样直接注入气相色谱仪中,通过阀的两次切换,将强极性的含氧化合物组分从非极性柱导入到极性柱,使得甲缩醛、二甲醚、甲基叔丁基醚、丙酮、甲醇、乙醇、丙醛和丁醛共9种含氧化合物与液化石油气中烃类组分完全分离。结果显示,甲缩醛等9种含氧化合物在0.01%(v/v)~5.0%(v/v)范围内呈现良好的线性,相关系数均大于0.99,样品重复测定5次,相对标准偏差小于3%,加标回收率在92.11%~104.40%之间,含氧化合物检出限可达0.0003%(v/v)~0.0021%(v/v)。     

高效液相色谱-质谱法测定车用清洗剂中烷基酚聚氧乙烯醚

建立了一种用于检测车用清洗剂中烷基酚聚氧乙烯醚的高效液相色谱-质谱法。流动相采用5 mmol/L乙酸铵和甲醇混合溶液,采用梯度淋洗模式,色谱柱柱温为40℃,流速为0.3 mL/min,进样量为10μL,质谱检测器为电喷雾离子源(ESI),采用选择离子(SIM)正模式。该法所建立的辛基酚聚氧乙烯醚(OPEO)和壬基酚聚氧乙烯醚(NPEO)的线性范围分别为1.0~50.0和0.5~50.0 mg/L,线性系数r均大于0.999,辛基酚聚氧乙烯醚和壬基酚聚氧乙烯醚的方法检出限分别为1.0和0.5 mg/kg,精密度分别为1.5%和2.8%(n=8),加标回收率分别为80.0%~98.3%和88.5%~100.2%。该方法操作简单、准确、快捷,可用于车用清洗剂中辛基酚聚氧乙烯醚及壬基酚聚氧乙烯醚的定性与定量检测。     

脂肪醇聚氧乙烯醚的HLB值分析方法研究

采用水数法,选择异丙醇/甲苯和1,4-二氧六环/苯两种溶剂体系测定了不同碳链长度和不同EO链长度的脂肪醇聚氧乙烯醚的HLB值。通过多项式方程拟合以及与文献计算值比较,确定1,4-二氧六环/苯是测定脂肪醇聚氧乙烯醚HLB值的比较好的溶剂系统。     

大气压离子源-质谱检测方法及其在环境生态领域的应用

大气压离子源-质谱法能够在大气压环境下直接分析样品,基质复杂的环境样品只需要简单预处理甚至不需要预处理,显著提高了质谱分析的效率,是近年来较为热门的质谱检测方法。本文介绍了大气压电离源的基本原理、结构和技术进展。此外,还对大气压离子源-质谱法在环境生态领域的最新应用进行了介绍。     

质谱分析导向的稳定同位素标记技术进展

介绍了近年来发展的一系列具有代表性的质谱分析导向的低残留稳定同位素标记技术:二甲氧基甲砜基嘧啶衍生化、低残留稳定同位素标记季铵化衍生化、新型胍剂化合物的衍生化等技术与方法。一些在常规电喷雾或基质辅助激光解吸电离条件下无法有效离子化的目标分子,在衍生化后产生新的正电荷中心或成为容易被电离物种而被质谱检测,从而提高了这类化合物的质谱学检测灵敏度。该类研究显著优势在于所开发的衍生化试剂本身不是离子型化合物,新产生的电荷中心或易于离子化的基团由衍生化反应引入。过量的衍生化试剂易于除去,不会对随后的质谱分析产生明显干扰。这一系列研究成果在代谢组学、食品安全分析、质谱成像以及单细胞分析等方面具有广泛的应用价值。     

窄分子量分布端羟基环氧乙烷-四氢呋喃共聚醚的合成及表征

用三氟化硼乙醚络合物(BF3.OEt2)为催化剂,乙二醇(EG)为起始剂,甲苯作溶剂,通过阳离子开环聚合制备出了窄分子量分布(w/n<1.3)的端羟基环氧乙烷-四氢呋喃(TEO)共聚醚,探讨了聚合温度、时间、反应介质、加料方式、起始剂及单体配比对分子量及其分布的影响,采用凝胶渗透色谱-多角度激光散射联用仪(SEC-MALLS)对其分子量及分布进行准确的测定,并用IR和1HNMR对共聚醚结构进行了表征。研究表明:有EG存在时,采用一次加料的方式,以甲苯为溶剂,温度为0℃,单体配比为11,∶反应时间为5 h的条件下制得的共聚醚具有分子量分布较窄的特点。     

窄分布脂肪醇聚氧乙烯醚的合成研究

在KOH和窄分布专用均相催化剂作用下,分别合成了2种不同平均EO加合度的AEO。根据合成过程中EO的消耗量计算得到理论平均EO加合度,气相色谱法分析了产品组成分布,对常规及窄分布AEO的EO分布、平均EO加合度对分子量分布的影响等进行了研究。结果表明,窄分布AEO气相色谱图中C_(12)(EO)_7的峰面积很小,基本看不到C_(14)(EO)_7的峰;对于常规及窄分布AEO,AEO2组分中游离脂肪醇质量分数低于AEO_(1.85),EO加合度为1～4组分的总质量分数则高于AEO1.85;窄分布AEO组分中游离脂肪醇和EO加合度大于4组分的质量分数明显低于常规AEO,而EO加合度为1～4组分的质量分数明显高于常规AEO,分子量分布呈泊松分布,表现出明显的窄分布特点。     

Study on anionic polymerization of ethylene oxide initiated by ammonium/triisobutylaluminum

In this paper, ammonium/triisobutylaluminum was used as an initiating system for anionic polymerization of ethylene oxide (EO). When the amount of triisobutylaluminum versus ammonium was in excess, a fast polymerization rate was achieved at room temperature and allowed polyethylene glycol synthesized with a high molecular weight and narrow molecular weight distribution. It was found that triisobutylaluminum may play two roles during the polymerization, one is that it can react with ammonium to form “ate” complex as an efficient initiator for EO polymerization, and the other is that it exerts a significant activating effect on the monomer. The catalytic effect of triisobutylaluminum in EO polymerization was elucidated by using quantum chemical calculations at density functional theory level, involving thermo-chemistry parameters. The studies show that EO homopolymerization cannot be conducted without the aid of catalyst due to the big energy difference of bonding orbitals. The interaction between EO and trialkylaluminum makes the electron cloud distribution and energy gap of EO molecule change, which indicates trialkylaluminum can activate the monomer. In addition, because of the lower enthalpy of formation, the formation of “ate” complex is prior to the interaction of trialkylaluminum and EO.     

Polymerization of ethylene oxide initiated by lithium derivatives via the monomer-activated approach: Application to the direct synthesis of PS-b-PEO and PI-b-PEO diblock copolymers

The anionic polymerization of ethylene oxide (EO) initiated by lithium derivatives is extremely sluggish and only yields very low molar mass EO oligomers because of the low reactivity of lithium alkoxide species. We show here that using the monomer-activated anionic polymerization approach, one can activate the C-O-Li bonds towards EO polymerization at low temperature and in non polar media. Starting from living polystyryllithium and polyisoprenyllithium, addition of triisobutylaluminum (i-Bu₃Al) in excess to lithium species triggers the propagation reaction of EO, allowing the direct synthesis, in a few hours, of poly(styrene-b-ethylene oxide) and poly(isoprene-b-ethylene oxide) diblock copolymers, with a molar mass of the PEO block up to 10 000 g/mol.     

某些聚氧乙烯型非离子表面活性剂EO数的红外光谱测定法

本文观察了烷基酚聚氧乙烯醚及月桂醇聚氧乙烯醚随环氧乙烷基(EO)数目(n)的改变其红外光谱的变化规律,并研究了聚氧乙烯链长的红外光谱测定方法,采用液膜法制样和光密度比值与n值的线性回归法求EO数,此法可快速简便地测得平均乙氧基化程度且结果可靠。     

某些聚氧乙烯型非离子表面活性剂EO数的红外光谱测定法

本文观察了烷基酚聚氧乙烯醚及月桂醇聚氧乙烯醚随环氧乙烯基（ＥＯ）数目（ｎ）的改变其红外光谱的变化规律，并研究了聚氧乙烯链长的红外光谱方法，采用液膜法制样和光密度比值与ｎ值的线性回归法求ＥＯ数，此法可快速简便地测得平均乙氧基化程度且结果可靠。     

Ethylene oxide oligomer distribution in nonionic surfactants via high performance liquid chromatography (HPLC)

A high performance liquid chromatography (HPLC) method using adsorption columns combined with linear gradient elution has been developed for the determination of ethylene oxide (EO) distribution in nonionic surfactants. The quantitative ethoxylate adduct distribution in single-carbon-number and mixed-carbon-number primary alcohol-based samples can be obtained. The HPLC method is also applicable for determining the molar EO distributions in diverse ethylene oxide adduct compounds such as alkylphenol ethoxylates, branched alcohol ethoxylates and secondary alcohol ethoxylates. Nonionic surfactant samples containing adducts up to 25 mol have been successfully separated and the individual adducts quantitated.     

Effect of PEO-PPO-PEO structure on the compressed ethylene-induced reverse micelle formation and water solubilization

Some of the poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) tri-block copolymers aggregate in p-xylene upon addition of ethylene and form reverse micelles at higher temperature at which the reverse micelles cannot be formed without addition of compressed ethylene. An abrupt increase of water solubilization is observed at a certain ethylene pressure. The effects of surfactant structure, such as the ratio of EO (EO weight percent) and the molecular mass, on the copolymer micellization and the solubilization of water in such systems are studied. For the copolymers with the same length of PO block, higher EO ratios facilitate the reverse micelle formation. However, as the EO ratio reaches 70%, it cannot form reverse micelles because the hydrophilicity is too high. For the copolymers with same composition, higher molecular weight is favorable to forming the reverse micelle due to the hydrophilic and folding effects, respectively. The reverse micelle solution can solubilize water with W₀ (molar ratio of water to EO segment) up to 4.1.     

低相对分子质量聚氧化乙烯的聚合研究

用自制氨钙催化剂合成低相对分子质量的聚氧化乙烯(PEO),用主成分分析法分析了环氧乙烷用量、溶剂用量、反应温度和反应时间对产物的相对分子质量的影响,并用红外光谱、DSC对产物进行了表征,确认为聚氧化乙烯均聚物。实验结果表明,环氧乙烷74 g、溶剂2.5 L、反应温度25℃、反应时间7 h时,收率达99.1%,相对分子质量为33.1万。     

Determination of ethylene oxide oligomer distributions in alcohol ethoxylates by HPLC using a rotating disc-flame ionization detector

A high performance liquid chromatographic (HPLC) method has been developed for the quantitative determination of ethylene oxide (EO) oligomer distributions (% wt) in acetylated alcohol ethoxylates, R(OCH₂CH₂)_nOH, from n=0, 1 to n=30 using a rotating disc-flame ionization detector. Both single carbon number and mixed carbon number alcohol-based (NEODOL® ethoxylates) samples have been analyzed by gradient elution with 2 different solvent systems on a Waters μ-Porasil column. With both solvent systems, 95% hexane is the initial solvent but with one system, 100% acetone is the final solvent and with the other, 10% methanol/90% acetone is used. The latter solvent elutes the higher ethoxylates from n=21 to n=30 quantitatively from the μ-Porasil column which the 100% acetone solvent fails to do. The 100% acetone solvent separates n=2 and n=3 from n=0,1 which the methanol-containing solvent does not do. Response factors for n=3 and n=8 have been experimentally determined and the response factors for the other EO units have been calculated from these 2 results. The corrected EO oligomer distributions for both NEODOL® 25-9 and NEODOL® 23-6.5 determined by HPLC are in good agreement with those determined earlier by circular thin layer chromatography (up to n=16 can be determined by this method). The average EO numbers determined by the HPLC method and by a wet chemical (phthalic anhydride) method are in excellent agreement for the above 2 samples and a sample of NEODOL® 23-7.5. The results are discussed in terms of Snyder’s theory for gradient elution in HPLC using the gradient steepness parameter.