| 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.
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