FREE VOLUME DURING CURING REACTION OF THERMOSETTING RESIN STUDIED BY POSITRON ANNIHILATION

正电子湮灭研究热固性树脂固化反应过程中的自由体积

• 批准号: 08651062
• 负责人: SUZUKI Takenori
• 金额: $ 1.41万
• 依托单位: High Energy Accelerator Research Organization
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08651062/
• 关键词: Positron Annihilation; Thermosetting resin; Polymerization; Free Volume; Cyanate; Lifetime; Positronium; Epoxy resin; 重合度; 陽電子の寿命; エポチシ樹脂硬化過程

Positron annihilation lifetime spectroscopy (PALS) has been applied successfully in solid state physics to detect defects and impurities. Recently, PALS has been applied to polymers. Positrons injected into polymers from radioisotopes such as ^<22>Na lose energy through interaction with atoms and molecules. After loosing the energy, positrons with a few hundred eV make the terminal spurs, which consist of ions, electrons and positrons, and then the positrons from hydrogen like atom, positronium (Ps). Ps diffuses in polymers until it is trapped in intermolecular spaces. Ps decays in these spaces and the size can be measured by the long lifetime (tau_3) of ortho-Ps.In this research, polymerization of bisphenol A dicyanate was examined using PALS and the increase in the specific volume was observed with the increase in the degree of polymerization. Also free volumes of several epoxy resins have been studied. The shift of the size of free volumes was observed when a THPM epoxy resin absorbed water.Also, the relaxation of polymer structures was discussed using PALS.After quenching the novolac epoxy resins to liquid nitrogen temperature, the large intermolecular spaces were observed, which would be formed by combining several small spaces due to the stress among polymer chains.

正电子湮灭寿命谱（PALS）已成功地应用于固体物理中检测缺陷和杂质。近年来，PALS已被应用于聚合物。从放射性同位素（如^<22>Na）注入聚合物的正电子通过与原子和分子的相互作用失去能量。几百eV的正电子在失去能量后产生终端杂散，终端杂散由离子、电子和正电子组成，然后是来自类氢原子的正电子——正电子（Ps）。Ps在聚合物中扩散，直到它被困在分子间空间中。Ps在这些空间中衰减，其大小可以通过正交Ps的长寿命（tau_3）来测量。在本研究中，利用PALS对双酚A双氰酸酯的聚合进行了研究，并观察到随着聚合程度的增加，比体积的增加。还研究了几种环氧树脂的自由体积。观察了THPM环氧树脂吸水后自由体积大小的变化。同时，用PALS讨论了聚合物结构的弛豫。将新伏拉克环氧树脂淬火至液氮温度后，由于聚合物链之间的应力作用，多个小空间组合而成的大分子间空间。

项目成果

T.Suzuki et al.: "Radiation effect on polypropylene studied by relaxational behavior at low temperature using positron annihilation" Polymer. 37. 5521-5524 (1996)

T.Suzuki 等人：“利用正电子湮灭通过低温松弛行为研究聚丙烯的辐射效应”聚合物。

T.Suzuki et al.: "Free-volume characteristics and water absorption of novolac epoxy resins investigated by positron annihilation" Polymer. 37. 3025-3030 (1996)

T.Suzuki 等人：“通过正电子湮没研究酚醛环氧树脂的自由体积特性和吸水率”聚合物。

Y.Kobayashi, T.Suzuki et al.: "positronium formation in polypropylene and polyethylene, -effects of gamma-irradiation and Electric field-" Materials Science Forum. 255-257. 67-71 (1997)

Y.Kobayashi、T.Suzuki 等人：“聚丙烯和聚乙烯中的正电子素形成，-伽马辐射和电场的影响-”材料科学论坛。

N.Oshima, T.Suzuki et al.: "Design of a high-efficiency short-pulsed positron beam system" Applied Surface Science. 116. 82-86 (1997)

N.Oshima、T.Suzuki 等人：“高效短脉冲正电子束系统的设计”应用表面科学。

T.Suzuki et al.: "Free volume of cyanate resins studied by positron annihilation" J.Radioana.Nuc.chem. 210. 555-562 (1996)

T.Suzuki 等人：“通过正电子湮灭研究氰酸酯树脂的自由体积”J.Radioana.Nuc.chem。