【作者】 彭琳；

【导师】 赵高凌；

【作者基本信息】 浙江大学 ， 材料学， 2007， 硕士

【摘要】 液晶显示（LCD）已经逐渐成为显示技术的主流。随着液晶显示技术水准的提高，对其基板玻璃的性能提出了更高的要求。由于制备工艺的复杂性，需要基板玻璃的尺寸稳定性要好，耐腐蚀性好，铝硼硅系玻璃可以满足这些基本条件。另外，铝硼硅玻璃还有着其它极为广泛的应用，可以用于光学组件、绝缘材料，耐热耐化学侵蚀容器，放射性废弃物的隔绝囊，玻璃纤维等等。然而，由于铝硼硅玻璃中SiO₂，B₂O₃和Al₂O₃的共存，网络结构的混合性质仍然不清楚，但这对于控制粘度、网络离子的扩散率，以及其它由熵不对称性影响的性质有着重要作用。因此，研究铝硼硅系玻璃的成分组成对结构的影响是十分必要的，而且国内对此的研究还尚未起步。本文采用了传统的熔融退火方法制备SiO₂-B₂O₃-Al₂O₃-RO（R’O₂）（R：碱土金属氧化物，Zn以及Cd；R’：Ti，Zr）系玻璃。玻璃的成分变动范围如下：SiO₂（65-70.8mol％）；B₂O₃（6.7-13.5mol％）；Al₂O₃（9.5-16.3mol％），∑RO（R’O₂）12mol％（0-2.4％MgO，0-4.8％CaO，0-2.4％SrO，0-2.4％BaO，0-2.4％ZnO，0-2.4％CdO，0-2.4％TiO₂，0-2.4％ZrO₂）。采用红外吸收光谱、NMR等分析手段，研究了玻璃中各类网络形成体、中间体（包括SiO₂，B₂O₃以及Al₂O₃，TiO₂和ZrO₂）和网络修饰体（包括碱土族金属氧化物MgO，CaO，SrO，BaO和过渡族金属ZnO，CdO）对铝硼硅玻璃的结构的影响。结果表明该系统玻璃中，硼的结构主要以三角体[BO₃]和四面体[BO₄]两种形态存在，其中[BO₄]的量相对较多；铝的结构主要以四面体[AlO₄]存在，含有少量的[AlO₅]、[AlO₆]结构。随着n（SiO₂）／n（B₂O₃）增大，[BO₃]的量减少；随着n（Al₂O₃）／n（B₂O₃）的增大，[BO₃]的量在比例为2.2时出现最大值。少量的过渡族中间体（IVB族）的加入影响了网络的混合状况。另外，随着加入的修饰体阳离子半径的增加，对网络结构单元的振动的影响变大。此外，本文还研究了玻璃中各组分对玻璃性能的影响。研究表明：随着n（SiO₂）／n（B₂O₃）的增大，热膨胀系数成增加趋势，密度出现极大值；随着n（Al₂O₃）／n（B₂O₃）的增大，热膨胀系数出现极值，密度总体上升，耐水、酸性都先增强后减弱，而耐碱性先减弱后增强，介电常数和损耗都呈现减小趋势；随nRO（CaO，SrO，BaO）／n（MgO）的增大，密度总体增加，耐酸，耐碱性都变好，介电损耗成下降趋势，但这些性能在替换比为1／2时都出现破折点。相对介电常数ε，随CaO／MgO的增加而增加，随SrO（BaO）／MgO的增加而降低。随着过渡族元素（ⅡB族：ZnO，CdO）原子序数的增加，密度减小，耐酸、碱性都变好，介电损耗和介电常数都是增加的；而随着ⅣB族（TiO₂，ZrO₂）原子序数的增加，密度增加，耐酸性变差而耐碱性变好，介电损耗和介电常数都增加。总的来说，本研究系统的玻璃，热膨胀性能总体优异（1.86×10⁶～2.77×10⁶／K），化学稳定性（酸腐蚀失重比最小达到0.08％，碱腐蚀失重量最小达到0.03％，表面积失重比达到0.012g／cm²）、密度（最小达到2.296g／cm³）和介电性质（介电常数最小为30.262，介电损耗最低达到1.43％）都符合平板显示应用的要求。更多还原

【Abstract】 Nowadays, liquid crystal display has been the dominate one in the display technologies. It’s required to improve the properties of substrate glasses as the LCD developing. Due to the complex preparation process, the LCD substrate glass needs a good dimensional stability （thermal stability） and chemical durability, and alumino-borosilicate glass can meet to these basic requirements. In addition, alumino-borosilicate glass has a wide-ranging application, such as optical element, chemical and heat-resistant containers, sequestration of radioactive waste, electrode glasses and fiber glasses etc.. However, the mixing behavior of network is still ambiguity because of the co-existing of SiO₂, B₂O₃ and Al₂O₃ in alumino-borosilicate glass. This has an important role in controlling viscosity, network cation diffusivity and other properties affected by the configurationally entropy. Therefore, it’s important to study the effect of compositions on the structure. In our knowledge, the study of this topic is still at initial step.In this study, SiO₂-B₂O₃-Al₂O₃-RO （R’O₂） （R=Mg, Ca, Sr, Ba, Zn and Cd, R’= Ti, Zr） glasses were made by melt-annealing method. The range of glasses components in molar fraction were as following: SiO₂, 65-70.8%, B₂O₃, 6.7-13.5%, Al₂O₃, 9.5-16.3% , total RO,12%（0-2.4%MgO, 0-4.8%CaO, 0-2.4%SrO, 0-2.4%BaO, 0-2.4%ZnO, 0-2.4%CdO, 0-2.4%TiO₂, 0-2.4%ZrO₂ ）. The changes of glass structure with components （between network former and intermediate former Si, B, Al, and Ti and between modified cation Mg, Ca, Sr, Ba, Zn, Cd and Zr） variety were investigated by using Fourier transform infrared spectra and nuclear magnetic resonance spectroscopy. The results showed that boron existed as [BO3] and [BO4] units, and the fraction of [BO4] unit was the majority in this kind of aluminoborosilicate glass. Aluminum mainly existed as [AlO₄] unit with a small mount of [AlO₅] and [AlO₆] units. When the molar ratio of SiO₂/B₂O₃ increased, the fraction of [BO₃] unit decreased. When the molar ratio of Al₂O₃/B₂O₃ increased, thefraction of [BO₃] unit got maximum value. A few transition metals （ⅣB group） doped influenced the mixing situation of network. Besides, the affection on the networkunit’s vibrations increased as the radius increasing.Furthermore, the effects of compositions on properties have studied. The results areshowed as follows. When the molar ratio of n（SiO₂/B₂O₃） increased, the thermal expansion coefficients （α-values） increased and the densities got a maximum value （at n=7.8）. When the molar ratio of n（Al₂2O₃/B₂O₃） increased, the thermal expansion coefficients （α-values） got a maximum value（at n=1.45）, the densities increased on the whole, water and acid resistance enhanced first and then reduced, base resistance changed in contrast, and dielectric constant ￡ and loss both decreased. When the molar ratio of RO（CaO, SrO, BaO）/ MgO increased, the densities increased, acid and base resistance both enhanced, dielectric loss decreased, but these properties all got their turning point as the molar ratio being 1/2. The dielectric constant ε increased as CaO/MgO increasing and SrO（BaO）/MgO decreasing. When the atomic number of transition metal increased in ⅡB group, densities decreased, acid and base resistance both enhanced, and dielectric constant ε and loss both increased. While in ⅣB group, densities increased, acid resistance reduced and base resistance enhanced, and dielectric constant ε and loss both increased with atomic number increasing. Totally, in the alumino-borosilicate glass studied in this article, the thermal expansion character is excellent （value range: 1.86×10^～2.77×10⁶/K ）, chemical durability（minimum value: 0.08% in acid, and 0.03% 0.012g/cm² in base）, densities （minimum value: 2.296g /cm³）and dielectric property （minimum value: ε=30.262 and tg δ =1.43%）meet the requirement of the application of panel display.更多还原