Simultaneous determination of NOGE-related and BADGE-related compounds in canned food by ultra-performance liquid chromatography–tandem mass spectrometry

An improved analytical method enabling rapid and accurate determination and identification of bisphenol F diglycidyl ether (novolac glycidyl ether 2-ring), novolac glycidyl ether 3-ring, novolac glycidyl ether 4-ring, novolac glycidyl ether 5-ring, novolac glycidyl ether 6-ring, bisphenol A diglycidyl ether, bisphenol A (2,3-dihydroxypropyl) glycidyl ether, bisphenol A (3-chloro-2-hydroxypropyl) glycidyl ether, bisphenol A bis(3-chloro-2-hydroxypropyl) ether, and bisphenol A (3-chloro-2-hydroxypropyl) (2,3-dihydroxypropyl) ether in canned food and their contact packaging materials has been developed by using, for the first time, ultra-performance liquid chromatography coupled with tandem mass spectrometry. After comparison of electrospray ionization and atmospheric pressure chemical ionization in positive and negative-ion modes, tandem mass spectrometry with positive electrospray ionization was chosen to carry out selective multiple reaction monitoring analysis of novolac glycidyl ethers, bisphenol A diglycidyl ether, and its derivatives. The analysis time is only 5.5 min per run. Limits of detection varied from 0.01 to 0.20 ng g(-1) for the different target compounds on the basis of a signal-to-noise ratio (S/N) = 3; limits of quantitation were from 0.03 to 0.66 ng g(-1). The relative standard deviation for repeatability was <8.01%. Analytical recovery ranged from 87.60 to 108.93%. This method was successfully applied to twenty samples of canned food and their contact packaging materials for determination of migration of NOGE, BADGE, and their derivatives from can coatings into food.     

Microwave‐assisted extraction for the simultaneous determination of Novolac glycidyl ethers,bisphenol A diglycidyl ether,and its derivatives in canned food using HPLC with fluorescence detection

A microwave‐assisted extraction (MAE) protocol and an efficient HPLC analysis method were first developed for the fast extraction and simultaneous determination of bisphenol F diglycidyl ether (Novolac glycidyl ether 2‐Ring), Novolac glycidyl ether 3‐Ring, Novolac glycidyl ether 4‐Ring, Novolac glycidyl ether 5‐Ring, Novolac glycidyl ether 6‐Ring, bisphenol A diglycidyl ether, bisphenol A (2,3‐dihydroxypropyl) glycidyl ether, bisphenol A (3‐chloro‐2‐hydroxypropyl) glycidyl ether, bisphenol A bis(3‐chloro‐2‐hydroxypropyl) ether, bisphenol A (3‐chloro‐2‐hydroxypropyl) (2,3‐dihydroxypropyl) ether in canned fish and meat. After being optimized in terms of solvents, microwave power and irradiation time, MAE was selected to carry out the extraction of ten target compounds. Analytes were purified by poly(styrene‐co‐divinylbenzene) SPE columns and determinated by HPLC‐fluorescence detection. LOD varied from 0.79 to 3.77 ng/g for different target compounds based on S/N=3; LOQ were from 2.75 to 10.92 ng/g; the RSD for repeatability were <8.64%. The analytical recoveries ranged from 70.46 to 103.44%. This proposed method was successfully applied to 16 canned fish and meat, and the results acquired were in good accordance with the studies reported. Compared with the conventional liquid–liquid extraction and ultrasonic extraction, the optimized MAE approach gained the higher extraction efficiency (20–50% improved).     

Hydrosilylation of allyl glycidyl ether with triethoxysilane

Hydrosilylation of allyl glycidyl ether with triethoxysilane in presence of Speier’s catalyst leads to triethoxy(3-glycidoxypropyl)silane and triethoxy(2-glycidoxy-1-methylethyl)silane and is accompanied by isomerization of allyl glycidyl ether and cleavage of the oxirane ring and the ether bond. An effect of admixtures in allyl glycidyl ether on the process is revealed. Some other hydrosilylation catalysts and additives to Speier’s catalyst are studied     

聚(β-氯乙基缩水甘油醚)的合成及其酯化反应动力学

本文合成了β-氯乙基缩水甘油醚及其聚合物。结果表明, AlEt3-0.5H2O体系是β-氯乙基缩水甘油醚的一种有效的聚合引发剂。研究了聚(β-氯乙基缩水甘油醚)的酯化反应动力学, 并通过^1H NMR和IR光谱确立了酯化度的计算关系式。最后, 通过光交联的动力学研究发现, 酯化聚合物中的肉桂酰基含量为85%时, 材料的感光灵敏度最高。     

聚合物冠醚的合成与性能——Ⅶ.梳形聚醚的合成及络合、催化性能

近年来通过非冠醚单体的聚合以合成聚合物冠醚,国内外都有一些新的进展.环氧化合物开环聚合时可得到具有乙撑氧链的聚醚,我们选用含环氧基团的化合物作为聚合单体,同时在环氧基团上又引入另外的乙撑氧链,经过开环聚合得到相应的梳形聚醚的主链和侧链都含有乙撑氧链,具有开链冠醚的结构特点,尚未见报道.     

Cleavage of different ether bonds in butyl glycidyl ether and allyl glycidyl ether by K, K(15-crown-5)2

The kind of substituent in alkyl glycidyl ethers affects the course of their reaction with K⁻, K⁺(15-crown-5)₂. The cyclic oxirane ring is exclusively cleaved in the case of butyl glycidyl ether whereas the presence of the unsaturated allyl group in the glycidyl ether molecule unexpectedly prefers the scission of the linear ether bond. In both the systems organometallic intermediates are formed. They react with crown ether causing its ring opening. Allylpotassium formed from allyl glycidyl ether reacts also with another glycidyl ether molecule; the oxirane ring is opened in this case.     

Synthesis and photopolymerization of 1-propenyl glycidyl ether

The ambifunctional monomer, 1-propenyl glycidyl ether, was prepared from allyl glycidyl ether, by a ruthenium-catalyzed isomerization reaction in high yield. 1-Propenyl glycidyl ether undergoes facile photoinduced cationic polymerization to yield a crosslinked polymer. The structure of this polymer was studied using ¹H- and, ¹³C-NMR spectroscopies and employing well-characterized related polymers as models. The model polymers were prepared by the cationic polymerization of allyl glycidyl ether with BF₃OEt₂ followed by isomerization of the pendant allyl groups by a ruthenium catalyst. Subsequently, the resulting polyether-bearing pendant 1-propenyl ether groups was subjected to a diaryliodonium salt-photoinitiated polymerization. A comparison of the spectra of the polymers indicated the presence of cyclic acetal units in the polymer backbone. © 1994 John Wiley & Sons, Inc.     

Kinetics of the Polymerization of Ethyl Glycidil Ether and Allyl Glycidil Ether with BF3OEt2

The kinetics of the polymerization of ethyl glycidyl ether and allyl glycidyl ether with BF₃OEt₂ as catalyst has been studied. Chain transfer to the monomer has been evidenced. It increased with the monomer concentration and decreased with the increase of the dielectric constant of the solvent used and decreased in the presence of a monomer more basic than glycidyl ethers, for example, 1,3-dioxepane.     

系列单取代烷氧基-2-羟丙基-β-环糊精的合成与表征

以环氧氯丙烷和脂肪醇为原料, 通过相转移催化法合成了乙基、正丙基、正丁基和正戊基缩水甘油醚(1～4), 并利用所合成的缩水甘油醚和β-环糊精为原料, 分别在弱碱水溶液(1.5%)和强碱水溶液(30%)中制备并用硅胶柱分离出单2位取代的乙氧基、丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(1a～4a)和单6位取代的丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(2b～4b), 利用薄层色谱、红外光谱、差热扫描量热分析、质谱和核磁共振等手段对所合成的产品进行了表征.     

Selective cleavage of the linear ether bond in benzyl glycidyl ether and triphenylmethyl glycidyl ether by potassium alkalide as two-electron-transfer reagent

The linear ether bond was exclusively cleaved in benzyl glycidyl ether and triphenylmethyl glycidyl ether under the influence of K⁻, K⁺(15-crown-5)₂ (1), whereas the strongly strained three-membered oxacyclic ring remained undisturbed. Potassium glycidoxide and benzylpotassium were found as the primary reaction products of benzyl glycidyl ether with 1. Subsequently, benzylpotassium reacted with benzyl glycidyl ether giving the next potassium glycidoxide molecule and bibenzyl. Benzyl phenyl ether was used as a model compound to explain the mechanism of bibenzyl formation. The reaction of triphenylmethyl glycidyl ether with 1 resulted in potassium glycidoxide and stable triphenylmethylpotassium. After treating with a quenching agent a new glycidyl ether or glycidyl ester was obtained from potassium glycidoxide. These results were found when the reaction occurred at the excess of glycidyl ether. In another case, i.e. at the excess of 1 further reactions took place with the participation of potassium anions and various new compounds were observed in the reaction mixture after benzylation or methylation. Thus, the method of substrates delivery influences the course of studied processes in a decisive way.     

Fast and solvent-free microwave-assisted synthesis of thermoresponsive oligo(glycidyl ether)s

Low-molecular weight linear poly(glycidyl ether)s are typically synthesized via the “classical,” oxy-anionic ring-opening polymerization (ROP) of glycidyl ether monomers at elevated temperatures. To reduce reaction times, a fast process was developed to synthesize oligo(glycidyl ether)s (OGEs) in bulk at a gram-scale utilizing microwave heating. Well-defined thermoresponsive copolymers comprising glycidyl methyl ether and ethyl glycidyl ether with molecular weights of up to 3 kDa were synthesized via microwave-assisted ROP with reaction times of approximately 10 min. The fast reaction kinetics were attributed to the rapid and uniform heating and high temperatures reached during the reaction. Consequently, no significant microwave-specific acceleration of the oxy-anionic ROP was observed. The temperature-triggered phase transition of the OGEs in aqueous solution revealed cloud point temperatures that are highly dependent on the OGE molecular weight, concentration, and comonomer composition, which extends previously reported data. Furthermore, oligo(glycidyl ether) acrylates (OGEAs) with reactive, functional end groups were directly accessible via in situ quenching of the anionic, microwave-assisted ROP with acrylic acid chloride. The obtained thermoresponsive OGEA macromonomers represent a promising material for the functionalization of surfaces via radical grafting methods to obtain functional, thermoresponsive coatings with potential application in cell culture. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 2496–2504     

Study of chemical processes in the modification of epoxide polymers by aluminum oxide

The processes occurring during the modification of epoxy polymers by various polymorphic aluminum oxide modifications (γ-AlO(OH), γ-Al₂O₃, α-Al₂O₃) with epoxy groups were studied by the methods of IR Fourier spectroscopy, chemical analysis, and differential scanning calorimetry (DSC) by an example of a model compound (phenyl glycidyl ether). Two types of interactions were revealed: a direct chemical reaction of phenyl glycidyl ether with the surface hydroxy groups of alyminum oxide, and phenyl glycidyl ether homopolymerization. By processing by graphical method the data of chemical analysis on the diminishing in amount of epoxy groups in the course of the polycondensation reaction the value of activation energy 106–110 kJ mol⁻¹ of the process of phenyl glycidyl ether interaction with aluminum γ-oxide was determined.     

Synthesis and Polymerization Studies of Cyano Epoxides

Abstract

The polar epoxides β-cyanoethyl glycidyl ether, cyanomethyl glycidyl ether, β-chloro-β-cyanoethyl glycidyl ether, and 3,4-epoxy valeronitrile were prepared, characterized, and their polymerization reactions studied. Novel cyanoethyla-tion of glycidol produced the β-cyanoethyl glycidyl ether in a quantitative yield. Reported is the first practicable synthesis of epicyanohydrin, which failed to polymerize. Homo-, co-, and terpolymerizations of the polar β-epoxy nitriles with various alkylene oxides were achieved by employing a complex catalyst obtained from an aluminum alkyl, acetyl acetone, and water. The polymers produced a series of vulcanizable elastomers which displayed an ex-cellent balance of solvent resistance and low temperature flexibility, as well as good ozone resistance. The presence of a third monomer such as allyl glycidyl ether was required to facilitate rubber vulcanization. However, it was possible to vulcanize homo- and copolymers of β-chloro-βyanoethyl glycidyl ether through the pendant chlorine atom. Catalyst efficiency in all cases was poor due to the complexing of the aluminum catalyst by the nitrile function.     

具有中心功能基的网状聚合物冠醚Ⅱ．具有硫醚侧基的网状聚合物冠醚及其铂配合物的合成

通过β－乙硫乙基环氧丙基醚与一缩二乙二醇双环氧丙基醚开环共聚，合成了网状结构单元中具有硫醚侧基的网状聚合物冠醚，或交联大环聚醚。这类聚合物与铂金属形成的配合物，是烯烃与三乙氧基硅烷硅氢加成反应的高活性催化剂。     

Kinetics of Photocationically Curable Formulations Involving Glycerol Diglycidyl Ether and Phenyl Glycidyl Ether

Kinetic analysis of formulations based on glycerol diglycidyl ether and phenyl glycidyl ether were carried out in the presence of sulfonium salt as initiator at 35 mW cm^?2using photo differential scanning calorimeter and the final conversion was found to increase with an increase in phenyl glycidyl ether content. The effects of formulation monomer ratios at three different temperatures were studied. The variations in the observed kinetic parameters can be related to increase in mobility of reactive species with temperature, distance of counter ion from the propagating cationic center, as well as extent of crosslinking reaction which controlled the course and duration of the reaction. The applicability of autocatalytic kinetic model was also evaluated and the system underwent early gelation and the activation energy decreased with an increase in phenyl glycidyl ether content. Analysis of stable photocured films containing glycerol diglycidyl ether and phenyl glycidyl ether showed better thermal stability than rigid films obtained with glycerol diglycidyl ether.     

Anionic alternating copolymerization of 3,4‐dihydrocoumarin and glycidyl ethers: A new approach to polyester synthesis

Anionic copolymerizations of 3,4‐dihydrocoumarin (DHCM) and a series of glycidyl ethers (n‐butyl glycidyl ether, tert‐butyl glycidyl ether, and allyl glycidyl ether) with 2‐ethyl‐4‐methylimidazole as an initiator proceeded in a 1:1 alternating manner to give the corresponding polyesters, whose structures were confirmed by spectroscopic analyses and reductive scission of the ester bonds in the main chain with lithium aluminum hydride, followed by detailed analyses of the resulting fragments. The polyester obtained by the copolymerization of DHCM and allyl glycidyl ether inherited the allyl groups in the side chain, whose applicability to chemical modifications of the polyester was successfully demonstrated by a platinum‐catalyzed hydrosilylation reaction. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4092–4102, 2008     

毛白杨环氧水解酶的异源表达及其在催化拆分手性环氧化物中的应用

对已公布的全基因组进行检索发现,杨树(Populus tomentosa)至少含有24个预测为可溶性环氧水解酶的基因.从中选取了7个可能的环氧水解酶基因进行克隆,通过扩增得到其中5个毛白杨(Populus tomentosa Carr)环氧水解酶基因.序列分析显示,它们与已克隆的巨大芽胞杆菌环氧水解酶的同源性仅为24%～26%.对该系列基因进行了在E.coli中的异源表达,并将得到的5个环氧水解酶(PTEH1～5)用于缩水甘油苯基醚和对硝基苯乙烯氧化物的酶促水解反应.结果发现,其中3个重组酶具有显著的环氧水解酶活性.进一步研究表明,PTEH1和PTEH2对于缩水甘油苯基醚显示了一定的反常规的(R)-选择性,而PTEH5则优先水解(S)-构型的缩水甘油苯基醚.因此,毛白杨中环氧水解酶表现出多样性.     

阳离子和两性表面活性剂在聚甲基丙烯酸甲酯表面的吸附行为

利用座滴法研究了阳离子表面活性剂十六烷基醚羟丙基季铵盐(C₁₆PC)、十六烷基聚氧乙烯醚羟丙基季铵盐(C₁₆(EO)₃PC)和两性离子表面活性剂十六烷基醚羟丙基羧酸甜菜碱(C₁₆PB)、十六烷基聚氧乙烯醚羟丙基羧酸甜菜碱(C₁₆(EO)₃PB)溶液在聚甲基丙烯酸甲酯(PMMA)表面上的润湿性质, 考察了表面活性剂类型及浓度对接触角的影响趋势. 研究发现: 低浓度条件下表面活性剂分子可能以平躺的方式吸附到固体界面, 且亲水基团靠近固体界面, PMMA表面被轻微疏水化; 在高浓度时则通过Lifshitz-van der Waals 作用吸附, 亲水基团在外, PMMA表面被亲水改性. 聚氧乙烯基团(EO基团)的引入对阳离子表面活性剂的接触角影响不大; 而含有聚氧乙烯基团的两性离子表面活性剂在PMMA界面上以类似半胶束的聚集体吸附, 大幅度降低接触角.     

支链化甜菜碱和阳离子表面活性剂在聚甲基丙烯酸甲酯表面的吸附及其润湿性质

利用座滴法研究了两性离子表面活性剂支链十六烷基(聚氧乙烯)_n醚羟丙基羧酸甜菜碱(n = 0, 3)和阳离子表面活性剂支链十六烷基(聚氧乙烯)_n醚羟丙基季铵盐溶液在聚甲基丙烯酸甲酯(PMMA)表面上的润湿性质,考察了表面活性剂类型、结构及浓度对接触角的影响趋势。研究发现,表面活性剂浓度低于临界胶束浓度(cmc)时,分子通过氢键以平躺的方式吸附到PMMA界面,亲水基团靠近固体界面, PMMA表面被轻微疏水化;表面张力和粘附张力同时降低,导致此阶段接触角随浓度变化不大。浓度高于cmc时,表面活性剂通过疏水作用吸附,亲水基团在外, PMMA表面被明显亲水改性,接触角随浓度升高显著降低。由于具有相同的支链烷基,表面活性剂类型变化和聚氧乙烯基团的引入对接触角影响不大。     

缩水甘油苯基醚-缩水甘油正丁基醚共聚物磺酸钠的合成及表面活性

缩水甘油苯基醚-缩水甘油正丁基醚共聚物磺酸钠的合成及表面活性;缩水甘油苯基醚-缩水甘油正丁基醚共聚物磺酸钠; 合成; 表面性质; 胶束