polyethylene glycol | 28287-76-5

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: polyethylene glycol
• 英文别名: PEG-4000
• CAS: 28287-76-5
• 化学式: C₂H₅O₂
• 分子量: 61.0605
• InChiKey: QKCFVDWBORTSIN-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -1.4
• 重原子数：
  4
• 可旋转键数：
  1
• 环数：
  0.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  21.2
• 氢给体数：
  1
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  polyethylene glycol 在 氧气 作用下， 24.85 ℃ 、93.33 kPa 条件下， 生成 羟乙醛
  参考文献：
  名称：

  Laboratory and Theoretical Study of the Oxy Radicals in the OH- and Cl-Initiated Oxidation of Ethene

  摘要：

  The products of the OH-initiated oxidation mechanism of ethene have been studied as a function of temperature (between 250 and 325 K) in an environmental chamber, using Fourier transform infrared spectroscopy for end product analysis. The oxidation proceeds via formation of a peroxy radical, HOCH2CH2O2. Reaction of this peroxy radical with NO is exothernic and produces chemically activated HOCH2CH2O radicals, of which about 25% decompose to CH2OH and CH2O on a time scale that is rapid compared to collisions, independent of temperature. The remainder of the HOCH2CH2O radicals are thermalized and undergo competition between decomposition, HOCH2CH2O --> CH2OH + CH2O (6), and reaction with O-2, HOCH2CH2O + O-2 --> HOCH2-CHO + HO2 (7), The rate constant ratio, k(6)/k(7), for the thermalized radicals was found to be (2.0 +/- 0.2) x 10(25) exp[-(4200 +/- 600)/T] molecule cm(-3) over the temperature range 250-325 K. With the assumption of an activation energy of 1-2 kcal mol(-1) for reaction 7, the barrier to decomposition of the HOCH2CH2O radical is found to be 10-11 kcal mol(-1). A study of the Cl-atom-initiated oxidation of ethene was also carried out; the main product observed under conditions relevant to the atmosphere was chloroacetaldehyde, ClCH2CHO. Theoretical studies of the thermal and "prompt" decomposition of the oxy radicals were based on a recent ab initio characterization that highlighted the role of intramolecular H bonding in HOCH2CH2O. Thermal decomposition is described by transition state and the Tree theories. To quantify the prompt decomposition of chemically activated nascent oxy radicals, the energy partitioning in the initially formed radicals was described by separate statistical ensemble theory, and the fraction of activated radicals dissociating before collisional stabilization was obtained by master equation analysis using RRKM theory. The barrier to HOCH2CH2O decomposition is inferred independently as being 10-11 kcal mol(-1), by matching both of the theoretical HOCH2CH2O decomposition rates at 298 K with the experimental results. The data are discussed in terms of the atmospheric fate of ethene.

  DOI：

  10.1021/jp981937d
• 作为产物：
  描述：

  硫二甘醇 生成 polyethylene glycol
  参考文献：
  名称：

  US2023/312457

  摘要：

  公开号：

文献信息

• Noncovalent interaction of polyethylene glycol with copper complex of ethylenediaminetetraacetic acid and its application in constructing inorganic nanomaterials
  作者：Shu Zhen Pan、Le Xin Song、Jie Chen、Fang Yun Du、Jing Yang、Juan Xia

  DOI：10.1039/c1dt11090j

  日期：——

  In this study, we try to answer a fundamental question: what is the consequence of the noncovalent interaction between a polymer and a coordination compound? Here, polyethylene glycol (PEG-4000, PEG-b) and copper complex of ethylenediaminetetraacetic acid (H2CuY) were employed to solve this problem. A novel adduct (CEP) between H2CuY and PEG-b was prepared. Our results indicated several interesting findings. First, the introduction of H2CuY had no effect on the stacking structure of PEG-b but led to a large change in surface structure of the polymer. Second, there was a significant difference (117 K) in the maximum degradation temperature between the PEG and the CEP, suggesting that the noncovalent interaction can drastically improve the thermal stability of the PEG. Third, sintering experiments showed that H2CuY and CEP produced completely different decomposition products. The former formed Cu crystals in nitrogen and CuO in air, but the latter generated Cu and CuCl crystals with good crystallinity, respectively. Finally, three independent measurements: viscosity, conductivity and nuclear magnetic resonance in solution, provided useful information and insights from both sides of the noncovalent interaction. Probable interaction mechanisms and interaction sites were proposed. We consider that the current research could create the foundation for a new understanding of how the noncovalent adduct interaction between a metallic complex and a polymer relates to the change in physical and chemical properties of the adducted components.

  在本研究中，我们试图回答一个基本问题：聚合物与配位化合物之间的非共价相互作用会产生什么结果？为了解决这个问题，我们采用了聚乙二醇（PEG-4000，PEG-b）和乙二胺四乙酸铜络合物（H2CuY）。在 H2CuY 和 PEG-b 之间制备了一种新型加合物（CEP）。我们的研究结果表明了几个有趣的发现。首先，H2CuY 的引入对 PEG-b 的堆叠结构没有影响，但导致聚合物的表面结构发生了很大变化。其次，PEG 和 CEP 的最大降解温度存在显著差异（117 K），这表明非共价作用可大幅提高 PEG 的热稳定性。第三，烧结实验表明，H2CuY 和 CEP 产生了完全不同的分解产物。前者在氮气中形成 Cu 晶体，在空气中形成 CuO，而后者则分别生成结晶度良好的 Cu 和 CuCl 晶体。最后，三种独立的测量方法：溶液中的粘度、电导率和核磁共振，为非共价相互作用的双方提供了有用的信息和见解。我们提出了可能的相互作用机制和相互作用位点。我们认为，目前的研究可以为重新理解金属复合物与聚合物之间的非共价加成相互作用与加成成分的物理和化学特性变化之间的关系奠定基础。
• Kinetics of reactions of methylperoxy and 2-hydroxyethylperoxy radicals produced by the photolysis of iodomethane and 2-iodoethanol
  作者：Michael E. Jenkin、Richard A. Cox

  DOI：10.1021/j100161a049

  日期：1991.4

  The molecular modulation technique coupled with UV absorption spectroscopy has been used to investigate the UV spectra and kinetics of reactions of the methylperoxy radical (CH3O2) and the 2-hydroxyethylperoxy radical (HOCH2CH2O2), generated by the 254-nm photolysis of the organic iodides CH3I and HOCH2CH2I: RI + h-nu(lambda = 254 nm) --> R + I (7) and R + O2 + M --> RO2 + M (8). Measurements of the UV spectra of both RO2 radicals were complicated by the production of additional transient species absorbing strongly at wavelengths above 240 nm. These are believed to be CH3OOI and HOCH2CH2OOI formed as intermediates in the RO2-chaperoned recombination of iodine atoms. Both CH3O2 and HOCH2CH2O2 were found to obey second-order kinetic behavior owing to removal by a series of reactions initiated by the self-reactions: CH3O2 + CH3O2 --> products (9) and HOCH2CH2O2 + HOCH2CH2O2 --> products (10). The parameter k9obs/sigma (where k9obs is the observed second-order rate coefficient) had a value of (1.01 +/- 0.09) x 10(5) cm s-1 at 230 nm, independent of pressure in the range 10.8-760 Torr, at 298 K. Additional measurements made over the temperature range 268-350 K indicated that this parameter displays a weak negative temperature dependence. E/R was found to have a value of -220 +/- 72 K at 760 Torr, and a value of -92 +/- 53 K at 10.8 Torr. The parameter k10obs/sigma had a value of (6.8 +/- 0.4) x 10(5) cm s-1 at 230 nm (p = 760 Torr, T = 298 K). Assuming the photolysis of HOCH2CH2I leads exclusively to the production of HOCH2CH2O2, the following values of sigma(230 nm) and k10obs were concluded: sigma(230nm) = (2.35 +/- 0.25) x 10(-18) cm2 molecule-1 and k10obs = (1.60 +/- 0.17) x 10(-12) cm3 molecule-1 s-1. At lower pressures, HO2 was also generated in the HOCH2CH2I system in significant quantities, enabling investigation of reaction 11 at 10 Torr and 298 K: HOCH2CH2O2 + HO2 --> products (11). A value of k11 = (4.8 +/- 1.5) x 10(-12) cm3 molecule-1 s-1 was concluded from these measurements, based on the above value of sigma(230 nm).