端环氧基聚苯乙烯低聚的物合成与表征

采用阴离子聚合法,以正丁基锂(n-BuLi)为引发剂、乙二醇二缩水甘油醚(EGDE)为封端剂,在常压惰性气体保护下引发苯乙烯(St)聚合,制得端环氧基聚苯乙烯低聚物(PS-ep)。采用GPCI、R和1H-NMR对PS-ep进行表征,并用盐酸-二氧六环银量法测定端环氧基含量。结果表明:以EGDE为封端剂可以使端环氧基摩尔分数(xep)达到0.80左右;升高封端反应温度和延长封端反应时间有利于提高端环氧基的摩尔分数;EGDE与n-BuLi的摩尔比以4∶1为宜。     

乙二醇二缩水甘油醚的合成及作为阳离子型紫外光固化稀释剂性能研究

以三氟化硼乙醚络合物为催化剂,以氢氧化钠为成环反应的闭环剂,利用乙二醇和环氧氯丙烷为原料合成了乙二醇二缩水甘油醚.研究了催化剂三氟化硼乙醚络合物用量、环氧氯丙烷和乙二醇摩尔比、氢氧化钠和乙二醇摩尔比,以及成环反应温度这些因素对合成反应的影响.结果表明较好的合成反应条件是:三氟化硼乙醚络合物质量分数为0.40%,环氧氯丙烷和乙二醇较佳摩尔比为2.4:1,氢氧化钠和乙二醇较佳摩尔比为2.2:1,较佳的成环反应温度为30℃.同时,把乙二醇二缩水甘油醚作为稀释剂加入到环氧树脂E-51中,利用三芳基锍鎓六氟锑酸盐作为引发剂,制备了阳离子型紫外光固化涂料,其紫外光固化膜的拉伸强度为46.25MPa,杨氏模量为1487.26MPa,断裂伸长率为6.27%.     

一步合成二缩水甘油醚

本文报道了一种合成二缩水甘油醚的简便方法。不同于 Bartok 综述中的常规合成法,本法使用相转移催化剂,避免了常规方法中试剂前处理工作,并且将合成路线简化为一步.此法合成的乙二醇二缩水甘油醚和丁二醇二缩水甘油醚产率分别为33.4%和40.7%。气相色谱和色质联用谱分析粗产物发现相转移催化法合成产物主要是二缩水甘油醚。红外光谱分析也印证了色质联用谱结果。     

GAP黏合剂体系交联网络结构研究

为改善聚叠氮缩水甘油醚(GAP)黏合剂体系的网络结构,分别考察了GAP与二官能度的甲苯二异氰酸酯(TDI)或异佛尔酮二异氰酸酯(IPDI)预聚、缩二脲多异氰酸酯(N-100)与二官能度固化剂的种类和配比对GAP弹性体力学性能、网络结构参数、网络结构完整性以及拉伸断面形貌的影响.结果表明,将GAP与TDI预聚可提高体系交联网络结构的完整性,同时提高弹性体的断裂延伸率和最大拉伸强度.适量加入二官能度异氰酸酯能改善体系的网络结构完整性,由于预聚体中TDI与IPDI结构和反应活性的差别,GAP/TDI/N-100弹性体在N-100与TDI质量比为7∶3时体系网络结构最完整,而GAP/IPDI/N-100弹性体在N-100与IPDI质量比为5∶5时体系网络结构最完整;在相同的N-100含量下GAP/IPDI/N-100体系比GAP/TDI/N-100体系强度高,延伸率略低.随着N-100含量的减少,GAP/TDI/N-100体系最大拉伸强度(δ_m)从0.66 MPa降低到0.32 MPa,断裂延伸率(ε_b)从104.6%提高到506.3%;GAP/IPDI/N-100体系强度在W(N-100)∶W(IPDI)=7∶3时达到最大值0.69 MPa,断裂延伸率从103.2%提高到391.4%.扫描电镜(SEM)结果表明,弹性体的拉伸断面形貌与弹性体的网络结构完整性和力学性能具有良好的对应关系.     

超支化聚缩水甘油醚研究进展

超支化聚缩水甘油醚(HPG)是一种分子内部为醚键,分子周围有大量羟基的超支化聚合物.这些结构特点使超支化聚缩水甘油醚在催化剂载体、生物医药、聚合物电解质等领域具有重要意义.本文介绍了超支化聚缩水甘油醚的合成方法及其功能化的研究进展,并简要分析了其发展前景.     

盐酸阿米替林/海藻酸钠/壳聚糖微球的制备及释放性能

盐酸阿米替林;海藻酸钠;壳聚糖;微球;交联;乙二醇二缩水甘油醚     

活性稀释剂苄基缩水甘油醚丙烯酸酯的合成及性能表征

本文以苄基缩水甘油醚和丙烯酸为原料合成活性稀释剂苄基缩水甘油醚丙烯酸酯(BGEA),研究了反应温度、催化剂和阻聚剂用量对反应的影响.结果表明最佳的反应条件为:反应温度110℃左右,催化剂N,N’-二甲基苄胺质量分数为0.9%,阻聚剂对甲氧基苯酚质量分数为0.2%.后将BGEA作为稀释剂加入到双酚A型环氧丙烯酸树脂中配制成光固化涂料,利用TG、AFM等表征手段对光固化膜的热性能、表面形貌及物理机械性能进行研究.     

水性环氧树脂固化剂的制备及其涂膜性能研究

采用二乙烯三胺(DETA)与聚丙二醇二缩水甘油醚(PPGDGE)反应合成出DETA-PPGDGE-DETA型的多元胺加成物,然后再用一定比例环氧树脂E-20封端加成,制备出了水性环氧树脂固化剂。红外光谱(IR)及飞行时间质谱(TOF-MS)验证了该水性环氧固化剂的结构。考察了不同反应条件对固化剂结构与性能的影响,结果表明,二乙烯三胺/聚丙二醇二缩水甘油醚环氧基物质的量比为10∶1,用沸点稍高的二乙二醇丁醚(DGBE)将体系中残留小分子DETA蒸除干净,环氧树脂E-20封端20%伯胺氢时,固化剂与环氧乳液混合后的涂膜性能最佳。     

罐装饮料中双酚A-二缩水甘油醚与双酚F-二缩水甘油醚及其衍生物的快速检测

建立了固相萃取/超高效液相色谱法测定罐装饮料中9种双酚-二缩水甘油醚,包括双酚A-二缩水甘油醚(BADGE)及其衍生物BADGE·2H2O、BADGE·H2O、BADGE·2HCl、BADGE·HCl、BADGE·H2O·HCl和双酚F-二缩水甘油醚(BFDGE)及其衍生物BFDGE·2H2O、BFDGE·H2O的快速检测方法。采用叔丁基甲醚为提取溶剂,涡旋振荡提取,提取液氮吹至近干后用甲醇-水(2∶3)溶解,采用PLS亲水亲酯柱固相萃取净化。以Shim-pack XR-ODS-Ⅲ为分析柱,乙腈-水为流动相进行梯度洗脱。9种双酚-二缩水甘油醚在0.05~10 mg/L范围内线性关系良好,回收率为83.8%~98.7%,RSD为2.3%~5.6%,方法检出限为20μg/kg。该方法操作简单、灵敏度高,可在10 min内对罐装饮料中9种双酚-二缩水甘油醚进行快速检测。     

含介晶结构单元化合物改性环氧树脂E—51／DDM固化体系的动态力学行为

合成和表征了含有介晶结构单元的单环氧官能团化合物4-(4'-甲基基苯甲酰氧基)苯基缩水甘油醚(MPEP),以一定比例的MPEP加入到环氧树脂E-51/4,4'-二氨基二苯基甲烷(DDM)固化体系,获得了一系列在高分子链上悬挂介晶结构单元的固化网络结构,并对其动态力学行为进行了表征,侧链上介晶结构单元的引入使固化体系的交联密度降低,链段柔顺性增加,表现为与未加MPEP的体系相比,含有介晶结构单元的体系的玻璃化温度和动态模量下降,而且MPEP的加量越大,玻璃化温度和动态模量下降幅度越大.     

HEPT类化合物的QSAR研究

为定量结构／活性相关性研究提取了量子化学参数,拓扑指数Am,分子连接性指数^mxt及疏水性常数,同时应用正交变换和最佳变量子集算法（Leaps-and-Bonds)进行了变量压缩和选择,进而实施了多元回归分析,并由此结果进行了HEPT类化合物（1－[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine derivatives)的结构／活性关系的理论解释,进行了人工神经网络法对于该类化合物的活性预测,其结构明显好于多元回归法。     

Effect of the pH of the medium on the chemical shifts in the PMR spectra and on the distribution of the π-electron density

The dependence of the chemical shifts of the ring protons on the pH of the medium for a number of 4-hydroxyquinoline derivatives was studied by means of PMR spectroscopy. The dipolar and uncharged hydroxy forms exist in equilibrium in aqueous solutions. The effect of intramolecular hydrogen bonding on the character of the dependence of the chemical shift on the pH of the medium in the case of 3-piperidinomethyl-4-hydroxyisoquinoline was investigated. The possibility of the separate protonation of the ring nitrogen and the side-chain nitrogen in 3-piperidinomethyl-4-hydroxyisoquinoline was established. The distribution of the -electron density in 4-hydroxyisoquinoline is in good agreement with its chemical behavior.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1546–1549, November, 1971     

Effect of the pH of the medium on the chemical shifts in the PMR spectra and on the distribution of the π-electron density

The dependence of the chemical shift of the ring protons on the pH of the medium for a number of 3-hydroxyquinoline derivatives was studied by PMR spectroscopy. The regions of ionization of the molecules, which correspond to the ranges of acidic, neutral, and alkaline media, were found. In D₂O, 3-hydroxyquinoline is present only in the uncharged hydroxy form. The presence of intramolecular hydrogen bonding in 4-dimethylaminomethyl-3-hydroxyquinoline has a substantial effect on the character of the dependence of the chemical shift on the pH of the medium; the existence of separate protonation of the nitrogen atoms of the ring and the side chain of 4-dimethylaminomethyl-3-hydroxyquinoline was established. The distribution of the -electron density in the 3-hydroxyquinoline molecule is in good agreement with its chemical behavior during electrophilic substitution.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1540–1545, November, 1971.     

From the Micro- to the Macro-: Managing the Conservation of the Warship,Vasa

Sweden's famous warship, Vasa, sank on her maiden voyage in August 1628, and remained on the bottom of Stockholm harbour for 333 years. Raised in 1961, she became the first large-scale wooden object to be treated with polyethylene glycol (PEG). In the summer of 2000 a number of acidic salt precipitations were noticed on the surface of the ship and on wooden artefacts in the storerooms. An international research project has been established to look into the causes of this problem and suggest possible re-treatments. Meanwhile projects are underway to monitor movements in the ship, to build a better support system, and to replace the thousands of iron bolts holding the structure together, while a sophisticated new climate system has recently been installed in the museum.