In this report, the first observations of the anomalously strong viscosity behavior in the melt quenched (MQ) invert mixed oxy-sulfide Na₄P₂S_7-xO_x, 0 ≤ x ≤ 5, (NaPSO) glass series. We find that these glasses even with 67 mole% modifier, Na₂S, exhibit a calorimetric fragility index, m_cal, as small as 29 compared to typical values of ~ 60 to 80 for alkali silicate glasses with > 50 mole% SiO₂. We find that the calorimetric fragility of these glasses varies systematically with the extent of network forming bridging oxygens (BOs) in the glasses. The m_cal values were converted to kinetic fragility (m_vis) values and used with the measured T_gs to produce viscosity curves for the glasses using the Mauro-Yue-Ellison-Gupta-Allan (MYEGA) model. The viscosity of the glass with a minimum m_cal value of x = 2.5 was then shown to exhibit a viscosity that was as strong as some alkali aluminosilicate glasses.

In this report, the first observations have been made of anomalously strong viscosity behavior and correspondingly strong bulk glass formation and resistance to crystallization in a melt quenched (MQ) prepared series of invert, modifier content greater than the glass former content, mixed oxy-sulfide Na₄P₂S_7-xO_x, 0 ≤ x ≤ 5, (NaPSO) glasses. We find that these glasses even with 67 mole % modifier, Na₂S, and only 33 mole% glass former P₂S_5-xO_x, exhibit a calorimetric fragility index, m_cal, as small as 29 compared to typical values of ~ 60 to 80 for alkali silicate glasses with > 50 mole% SiO₂ and the theoretical minimum m_cal of ~ 15. The m_cal values were converted to kinetic viscosity fragility, m_vis, values and used with the measured glass transition temperatures, T_gs, to produce viscosity curves for the glasses using the Mauro-Yue-Ellison-Gupta-Allan (MYEGA) model. The viscosity of the glass with a minimum m_cal value of x = 2.5 was then shown to exhibit a viscosity that was as strong as, and for some compositions stronger than, the viscosity of alkali aluminosilicate glasses which have three dimensional network structures compared to the one dimensional chain structures observed in these MOS invert glasses. Consistent with these small values of fragility indices and therefore predicted higher viscosity above the glass transition temperature, T_g, in the supercooled liquid regime, these glasses are also particularly resistant to crystallization. For example, the x = 2.5 glass composition exhibits a crystallization temperature, T_C, more than 150K above its T_g. We find that the calorimetric fragility of these glasses varies systematically with the extent of network forming bridging oxygens (BOs) in the glasses. The structural change caused by incrementally replacing sulfur with oxygen has been found to have consistent, large effects on the thermal properties.

在本报告中，首次观察到在熔融淬火（MQ）中混合氧化硫Na ₄ P ₂ S _7-x O _x，0≤x≤5（NaPSO）玻璃系列的异常强粘度行为。我们发现，即使具有67摩尔％的改性剂Na ₂ S，这些玻璃也显示出比色脆性指数m _cal低至29，而SiO ₂ > 50摩尔％的碱金属硅酸盐玻璃的典型值为〜60至80 。我们发现，这些玻璃的量热脆性随玻璃中形成桥接氧（BOs）的网络程度而系统地变化。将m _cal值转换为动力学脆性（m _vis）值并与测得的T _g s一起使用Mauro-Yue-Ellison-Gupta-Allan（MYEGA）模型生成玻璃的粘度曲线。具有最小米玻璃的粘度_CAL然后为x = 2.5的值被示出为表现出的粘度，这是强如一些碱金属铝硅酸盐玻璃。

在此报告中，首次观察到在熔融淬火（MQ）制备的一系列反相玻璃中，异常强的粘度行为和相应的强块状玻璃形成以及抗结晶性，改性剂含量大于玻璃形成剂含量，混合氧硫化物Na ₄ P ₂ S _7-x O _x，0≤x≤5（NaPSO）玻璃。我们发现，即使使用67摩尔％的改性剂Na ₂ S和仅33摩尔％的玻璃形成剂P ₂ S _5-x O _x，这些玻璃也显示出比色度易碎指数m _cal低至29。 SiO> 50摩尔％的碱金属硅酸盐玻璃约为60至80₂和理论最小m _cal约为〜15。将m _cal值转换为动粘度脆性m _vis值，并与测得的玻璃化转变温度T _g s一起使用，以使用Mauro-约翰·埃里森·古普塔·艾伦（MYEGA）模型。玻璃的具有最小粘度米_CAL然后表明x = 2.5的值显示出的粘度与在这些MOS倒置玻璃中观察到的一维链状结构相比具有三维网络结构的碱金属铝硅酸盐玻璃的粘度一样强，并且在某些成分上比碱铝硅酸盐玻璃更强。与这些小数值的脆性指数相一致，并因此在过冷液体状态下预测了高于玻璃化转变温度T _g的更高粘度，这些玻璃还特别耐结晶。例如，x  = 2.5的玻璃成分的结晶温度T _C高于其T _g超过150K。。我们发现，这些玻璃的量热脆性随玻璃中形成桥接氧（BOs）的网络程度而系统地变化。已经发现，通过用氧气逐步替换硫而引起的结构变化对热性能具有一致的，大的影响。