Fundamental Study on conservation treatment of water-logged wood with CO2

CO2防腐处理浸水木材的基础研究

• 批准号: 13450324
• 负责人: INOMATA Hiroshi
• 金额: $ 1.66万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13450324/
• 关键词: PPO; Supercritical CO2; Polymerization; Two-step process; Phase Separation

Polyphenyleneoxide (PPO) is one of the important engineering plastics showing excellent mechanical, thermal, electrical and chemical properties at higher temperatures. In industry, PPO has been produced by oxidative-coupling reaction in toluene solvent and it has been pointed put that the solvent recovery plays an important role in determining the process feasibility. Additionally the viewpoint of green sustainable chemistry has brought the trend of solvent-free synthesis even for polymer industry.From these backgrounds, the synthesis of poly (phenylene oxide) (PPO) has been carried out in supercritical carbon dioxide (scCO_2) at 40 ℃ and 15 Mpa (one-step polymerization). The maximum yield and the weight-average molecular weight (Mw) of the synthesized PPO were ca. 70 % and 10,000 respectively. Two-step polymerization at 55 ℃, 22 Mpa or 70 ℃, 30 Mpa for 8 h was also tried successively after the synthesis at 40 ℃, 15 Mpa for 20 h, leading to increase the maximum yield and the Mw of the PPO up to ca. 80 % and 20,000 respectively. A small amount of diphenoquinone (DPQ) was produced as a by-product of PPO synthesis and its yield for the two-step polymerization was slightly larger (1.7 %) than that (ca.1.2 %) for one-step polymerization at 40 ℃ and 15 Mpa. The synthesized PPO was found to have similar glass transition temperature (T_g) of 200 ℃ to commercial one. These results indicated that the roles of ScCO_2 in this polymer synthesis were not only reaction solvent but also plasticizer for the polytmer, which allowed for us to progress the polymerization even after polymer-scCO_2 phase separation.

聚苯醚（PPO）是一种重要的工程塑料，在高温下具有优异的机械、热、电和化学性能。在工业上，PPO的生产主要是在甲苯溶剂中通过氧化偶联反应进行的，溶剂的回收是决定工艺可行性的重要因素。在此背景下，本论文以超临界二氧化碳（scCO_2）为反应介质，在40 ℃、15 MPa条件下，采用一步聚合法合成了聚苯醚（PPO）。合成的PPO的最大产率和重均分子量（Mw）约为1000。70%和10,000分别。在40 ℃、15 Mpa下合成20 h后，又尝试了55 ℃、22 Mpa或70 ℃、30 Mpa下两步聚合8 h，使PPO的最大产率和分子量均提高到约100%。80%和20,000分别。在40 ℃、15 MPa条件下，两步聚合的副产物联苯醌（DPQ）的产率（1.7%）略高于一步聚合的产率（约1.2%）。合成的PPO的玻璃化转变温度（Tg）为200 ℃。这些结果表明，ScCO_2在该聚合物合成中的作用不仅是反应溶剂，而且是聚合物的增塑剂，这使得即使在聚合物-scCO_2相分离之后，我们也可以进行聚合。

项目成果

Li, Guangshe, R.L.Smith, Jr., 猪股宏, 新井邦夫: "Synthesis and thermal decomposition of nitrate free boehmite nanocrystals by supercritical hydrothermal conditions"Materials Letters. 53. 175-179 (2002)

Li，Guangshe，R.L.Smith, Jr.，Hiroshi Inomata，Kunio Arai：“超临界水热条件下无硝酸盐的勃姆石纳米晶体的合成和热分解”Materials Letters 53. 175-179 (2002)。

Smith, Jr., R.L., 斉藤千恵, 鈴木幸雄, B.B.Lee, 猪股宏, 新井邦夫: "Temperature dependence of dielectric spectra of carbon dioxide and methanol mixtures at high-pressures"Fluid Phase Equilibria. 194-197. 869-877 (2002)

Smith, Jr., R.L.、Chie Saito、Yukio Suzuki、B.B.Lee、Hiroshi Inomata、Kunio Arai：“高压下二氧化碳和甲醇混合物的介电谱的温度依赖性”流体相平衡 194-197。 (2002)

Li, Guangshe, R.L.Smith, Jr., 猪股宏, 新井邦夫: "Preparation and Magnetization of Hematite Nanocrystals with Amorphous Iron Oxide Layers by Hydrothermal Conditions"Mater. Res. Bull. 37. 949-955 (2002)

Li，Guangshe，R.L.Smith，Jr.，Hiroshi Inomata，Kunio Arai：“通过水热条件制备和磁化具有非晶氧化铁层的赤铁矿纳米晶体”Mater。 37. 949-955 (2002)

L.P.Li., G.S.Li, R.L.Smith, 猪股宏: "Activation of Oxide-ion conduction in KNbO3 by addition of MG2+"Applied Physics Letters. 81. 2899-2901 (2002)

L.P.Li.、G.S.Li、R.L.Smith、Hiroshi Inomata：“通过添加 MG2+ 激活 KNbO3 中的氧化物离子传导”应用物理快报 81. 2899-2901 (2002)

L.P.Li., G.S.Li, R.L.Smith, H.Inomata: "Activation of Oxide-ion conduction in KNbO3 by addition of Mg2+"Applied Physics Letters. 81. 2899-2901 (2002)

L.P.Li.、G.S.Li、R.L.Smith、H.Inomata：“通过添加 Mg2 激活 KNbO3 中的氧化物离子传导”应用物理快报。