Nanotribology of Polysiloxane Ultrathin Films

聚硅氧烷超薄膜的纳米摩擦学

• 批准号: 10650890
• 负责人: TAKAHARA Atsushi
• 金额: $ 2.43万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650890/
• 关键词: Nanotribology; Lateral Force Microscopy; Organosilane Monolayers; Polysiloxane Ultyrathin Film; Thermal Molecular Motion; Infrared Spectroscopy; Phase Transition; Molecular Aggregation State; 摩擦力; 摩擦力顕微鏡; 原子間力顕微鏡; 表面構造; Langmuir法; 表面分子運動; FT

The organosilane monolayers are thermally and mechanically robust due to the presence of strong anchoring functional group at the hydrophilic part. When the alkyltrichlorosilane monolayer is polymerized on the water surface, the resulting polymer is polyalkylsiloxane. This organosilane monolayer can be immobilized onto the silicon wafer substrate by an upward drawing method. In this study, the alkyltrichlorosilane, fluoroalkyltrichlorosilane and their mixed monolayers were prepared by the Langmuir-Blodgett method at an air-water interface. The surface molecular motion of the monolayers were characterized by temperature dependence of IR spectra and lateral force. n-alkyltrichlorosilane (CHィイD23ィエD2(CHィイD22ィエD2)ィイD2n-1ィエD2SiClィイD23ィエD2 n=12 : DDTS, n=16 : HDTS, n=18 : OTS, n=22 ; DOTS, n=30 : TATS), 18-nonadecyltrichlorosilane (NTS, CHィイD22ィエD2=CH(CHィイD22ィエD2)ィイD217ィエD2SiClィイD23ィエD2), [2-(perfluorooctyl)ethyl]trichlorosilane (FOETS, CFィイD23ィエD2(CFィイD22ィエD2)ィイD27ィエD2(CHィイD22ィエD2)SiClィイD23 … More ィエD2) and [γ-(1H,1H,2H,2H-perfluorododecyloxy)propyl]triethoxysilane (FDOPTES, CFィイD23ィエD2(CFィイD22ィエD2)ィイD29ィエD2(CHィイD22ィエD2)ィイD22ィエD2O(CHィイD22ィエD2)ィイD23ィエD2Si(OCィイD22ィエD2HィイD25ィエD2)ィイD23ィエD2) were used to prepare the monolayer. Toluene solutions of organosilane were spread on the pure water surface at a subphase temperature of 293 K. Surface pressure-area (π-A) isotherms were measured with a computer-controlled home made Langmuir-trough. The monolayers were transferred onto the silicon wafer substrate by an upward drawing method, and then chemically immobilized onto the substrate with Si-OH groups. The magnitude of lateral force of alkylsilane monolayer increased with an increase in alkyl chain length. This increase is due to an increase in van der Waals interaction of alkyl chains. The fluoroalkylsilane showed a large friction force compared with that of alkylsilane at the corresponding chain length. A large lateral force of fluoroalkyl silane can be ascribed to the high shear strength of fluoroalkyl silane due to the rigid nature of fluoroalkyl chain and high polarity of CFィイD23ィエD2 end group. The temperature dependence of IR spectra was measured in order to characterize the structural transition of organosilane monolayers. The wavenumber of the peak assigned to the CHィイD22ィエD2 antisymmetric stretching band was apparently shifted from 2915.5 cmィイD1-1ィエD1 to 2917.7 cmィイD1-1ィエD1 at around 240 K and from 2917.7 cmィイD1-1ィエD1 to 2919.2 cm ィイD1-1ィエD1 at around 330 K. This result indicates that the rectangular-hexagonal and hexagonal-amorphous phase transitions of the OTS monolayer occurred at these temperatures. The magnitude of lateral force reflects the state of thermal molecular motion. A decrease in the magnitude of lateral force of the OTS monolayer was observed at around 240 K and 330 K. It seems reasonable to consider that these decreases in the lateral force corresponded to a decrease in the molecular density in the OTS monolayer due to rectangular to hexagonal phase transition at 240 K and a decrease in shear strength by activation of molecular motion due to the hexagonal to amorphous phase transition at 330 K. Less

由于在亲水部分存在强锚定官能团，有机硅烷单层具有热稳定性和机械稳定性。当烷基三氯硅烷单层在水面上聚合时，所得聚合物为聚烷基硅氧烷。该有机硅烷单分子层可以通过向上拉伸方法固定到硅晶片衬底上。本文采用Langmuir-Blodgett方法在空气-水界面上制备了烷基三氯硅烷、氟烷基三氯硅烷及其混合单分子膜。通过红外光谱和侧向力的温度依赖性表征了单分子膜的表面分子运动。正烷基三氯硅烷（CH氨基甲酸酯D23氨基甲酸酯D2（CH氨基甲酸酯D22氨基甲酸酯D2）氨基甲酸酯D2 n-1氨基甲酸酯D2 SiCl氨基甲酸酯D23氨基甲酸酯D2 n=12：DDTS，n=16：HDTS，n=18：OTS，n=22 ; DOTS，n=30：TATS）、18-十九烷基三氯硅烷（NTS，CH CH3D22 CH3D2 =CH（CH CH3D22 CH3D2）CH3D217 CH3D2SiCl CH3D23 CH3D2），[2-（全氟辛基）乙基]三氯硅烷（FOETS，CF氯丁D23三氯D2（CF氯丁D22三氯D2）三氯D27三氯D2（CH氯丁D22三氯D2）SiCl三氯D23 ...更多信息 [γ-（1H，1H，2 H，2 H-全氟十二烷氧基）丙基]三乙氧基硅烷（FDOPTES，CF β D23 β D2（CF β D22 β D2）β D29 β D2（CH β D22 β D2）β D22 β D2 O（CH β D22 β D2）β D23 β D2 Si（OC β D22 β D22 β D2 H β D25 β D2）β D23 β D2）用于制备单分子膜。将有机硅烷的甲苯溶液铺展在纯水表面，亚相温度为293 K。用计算机控制的国产朗缪尔槽测量表面压力-面积（π-A）等温线。通过上引法将单层膜转移到硅片衬底上，然后用Si-OH基团化学固定到衬底上。烷基硅烷单分子膜的侧向力随烷基链长的增加而增大。这种增加是由于烷基链的货车德瓦耳斯相互作用的增加。与相应链长的烷基硅烷相比，氟烷基硅烷表现出较大的摩擦力。氟烷基硅烷的大的侧向力可归因于氟烷基硅烷的高剪切强度，这是由于氟烷基链的刚性性质和CF-12 D23 - 12 D2端基的高极性。测量了有机硅烷单分子膜的红外光谱随温度的变化，以表征有机硅烷单分子膜的结构转变。在240 K附近，CH_（12）D_（22）反对称伸缩带的峰的波数从2915.5 cm ~（12）D_（1-这一结果表明，在此温度下，OTS单分子膜发生了矩形-六方和六方-非晶相变。侧向力的大小反映了热分子的运动状态。在240 K和330 K左右，OTS单层膜的侧向力减小。这似乎是合理的，认为这些减少在横向力对应于在OTS单层中的分子密度的减少，由于在240 K的矩形到六方相的相变和剪切强度的减少，由于在330 K的六方相到非晶相的相变的分子运动的激活。少

项目成果

9.K.Kojio,A.Takahara,K.Omote,T.Kajiyama: "Molecular Aggregation State of n-Octadecyltrichlorosilane Monolayers Prepared by the Langmuir and Chemisorption Methods"Langmuir. Vol.16(印刷中). (2000)

9.K.Kojio、A.Takahara、K.Omote、T.Kajiyama：“通过 Langmuir 和化学吸附方法制备的正十八烷基三氯硅烷单分子层的分子聚集状态”Langmuir 第 16 卷（出版中）。

K.Kojio,S.R.Ge,A.Takahara,T.Kajiyama: "Molecular Aggregation State of n-Octadecyltrichlorosilane Monolayer Prepared at an Air/Water Interface"Langmuir. 14. 971-974 (1998)

K.Kojio，S.R.Ge，A.Takahara，T.Kajiyama：“在空气/水界面制备的正十八烷基三氯硅烷单层的分子聚集状态”Langmuir。

K. Kojio, A, Takahara, T. Kajiyama: "Formation Mechanism of n-Octadecyltrichlorosilane MonolayerPrepared at Air/Water Interface"Colloid & Surf. A. (2000)

K. Kojio, A, Takahara, T. Kajiyama：“在空气/水界面制备的正十八烷基三氯硅烷单分子层的形成机制”胶体

K. Kojio, A. Takahara, T. Kajiyama: "Aggregation Structure and Surface Properties of 18-Nonadecenyltrichlorosilane Monolayer and Multilayer Films Prepared by Langmuir Method"ACS Symp. Ser., Silicones and Silicone-Modified Materials. Chap22. (2000)

K. Kojio、A. Takahara、T. Kajiyama：“朗缪尔法制备的 18-十九烯基三氯硅烷单层和多层薄膜的聚集结构和表面性能”ACS Symp。

A. Takahara, K. Kojio, T. Kajiyama: "Surface Structure and Surface Properties of Organosilane Monolayers"Journal of the Society of Silicon Chemistry, Japan. No.11. 19-22 (1999)

A. Takahara、K. Kojio、T. Kajiyama：“有机硅烷单层的表面结构和表面性质”日本硅化学学会杂志。