Chemical structure and mechanical properties of soda lime silica glass surfaces treated by thermal poling in inert and reactive ambient gases

This study employed thermal poling at 200°C as a means to modify the surface mechanical properties of soda lime silica (SLS) glass. SLS float glass panels were allowed to react with molecules constituting ambient air (H₂O, O₂, N₂) while sodium ions were depleted from the surface region through diffusion into the bulk under an anodic potential. A sample poled in inert gas (Ar) was used for comparison. Systematic analyses of the chemical composition, thickness, silicate network, trapped molecular species, and hydrous species in the sodium‐depleted layers revealed correlations between subsurface structural changes and mechanical properties such as hardness, elastic modulus, and fracture toughness. A silica‐like structure was created in the inert gas environment through restructuring of Si–O–Si bonds at 200°C in the Na‐depleted zone; this occurred far below T_g. This silica‐like surface also showed enhancement of hardness comparable to that of pure silica glass. The anodic thermal poling condition was found so reactive that O₂ and N₂ species can be incorporated into the glass, which also alters the glass structure and mechanical properties. In the case of the anodic surfaces prepared in a humid environment, the glass showed an improved resistance against crack formation, which implies that abundant hydrous species incorporated during thermal poling could be beneficial to improve the toughness.     

电子玻璃熔窑冷修施工技术

玻璃熔窑钢结构改造施工项目与新建项目在施工过程中有很大的差异,其中旧钢结构的拆除和舍取取决于其锈蚀损坏及矫正的难易程度,此外高空作业、防锈处理都对施工质量有着直接的影响。本人在对我公司这几年施工的玻璃熔窑玻璃熔窑改造施工技术方法进行总结的基础上对电子玻璃熔窑冷修施工技术进行了总结,以期对同类窑炉的冷修有所帮助。     

玻璃的脆性(二)

玻璃的脆性受玻璃成分和结构、玻璃的微观和宏观缺陷、表面环境影响。玻璃原子结构聚合程度的减少和各向异性结构(层、链)的形成,提供了剪切变形,降低了无机玻璃脆性。此外,较高的摩尔体积表示结构较开放,使形变容易,造成较小的脆性。     

Simulations of the surfaces of soda lime aluminoborosilicate glasses exposed to water

Molecular dynamics simulations of 7 compositionally different sodium calcium alumino‐borosilicate glasses showed formation of ⁴B and ⁵Al more consistent with experimental data without compromising the other structural features that match experimental results observed in recent simulations of these glasses. Analysis of the dry surfaces of these glasses show a lack of ⁴B in the top 5‐6 Å of the surface in comparison to the bulk concentration for all glasses and no ⁵Al. Upon exposure to water, the simulations show that the ³B in the top 5‐6 Å of the glasses are preferentially attacked, decreasing the number of B bonds to O originally from the glass, indicating a change in the glass network. Inclusion of all B–O bonds in the top 5‐6 Å (i.e., including O from water) shows a decrease in ³B but an increase in ⁴B that is consistent with NEXAFS analysis, which the simulations show are hydroxylated. There is an increase in the concentration of ³Al in the dry surface in comparison to the bulk, but exposure to water converts almost all of these ³Al to ⁴Al. Hydroxyl concentrations vary from 2.6/nm² to 4.1/nm², with SiOH and BOH dominating these surface hydroxyls. Upon exposure to water, network linkages to B are preferentially ruptured. This, and the preferential loss of the nonbridging oxygen sites attached to Na, provide atomistic evidence of the initial stages of removal of B and Na from glass surfaces exposed to water.     

常用结构测试方法的介绍及其在玻璃中的应用

简要介绍了各种内部结构测试（XRD、IR、NMR）和表面结构测试方法（SEM＋EDS、AFM、XPS）的基本原理和测试内容,并举例介绍了这些测试方法在玻璃本体及镀膜中的实际应用。     

GF表面的多步接枝改性及其对PP/GF复合材料拉伸性能的影响

为提高热塑性树脂聚丙烯(PP)与玻璃纤维(GF)之间的界面相容性和粘结强度,提出了一种对GF三步浸渍的方法,将GF逐步用(3-氨丙基)三乙氧基硅烷(γ–APS),1,6-己二异氰酸酯(HDI)及苄胺或十八胺处理,从而在GF表面接枝上长的分子链。利用接触角测定仪、衰减全反射傅立叶变换红外光谱(ATR–FTIR)仪和X射线光电子能谱(XPS)仪等手段,对改性后的GF表面进行了表征,证明了接枝反应的成功进行。将不同方法改性的GF与PP制备成单向PP/GF复合材料,对其进行了拉伸性能测试。结果表明,随着GF表面接枝的碳链增长,复合材料的拉伸强度逐渐增大。     

以工业水玻璃为原料制备纳米孔SiO2气凝胶块体材料

以工业水玻璃为硅源,采用三甲基氯硅烷[(CH3)3SiCl,TMCS]/正己烷(C6H14)/EtOH溶液对二氧化硅水凝胶进行表面改性处理,使水凝胶的溶剂交换和表面改性在一步同时完成.研究了pH值、改性剂对气凝胶的影响.结果表明,所制备的气凝胶具有典型的气凝胶结构特征,孔洞尺寸、比表面积分别在8～12 nm、600～640 m2/g范围内,颗粒尺寸小于100 nm.     

Ultralow voltage imprinting in GeS2–Ga2S3–AgI glasses for visible to middle-infrared diffraction gratings

A diffractive optical element (DOE) covering visible to middle-infrared regions is imprinted in chalcohalide glass by microthermal poling under ultralow voltages (~125 V). The effect of the poling voltage on the surface profiling, optical diffraction, optical transmittance, and anode-side structural rearrangement is investigated. Deformation of the surface profiling and diffraction order increase with increasing poling voltage, showing a saturation voltage of 125 V and a decrease in the transmittance within 10%. In addition to the normal vertical migration of silver ions, an obvious and unexpected transverse migration of silver ions and mutual structural transformation occur between homopolar bonds Ge–Ge (Ga–Ga) and S–S and the heteropolar bond Ge–S (Ga–S), which are key to forming the surface profiling and subsurface structures. Formation of the DOE mainly depends on the periodic subsurface microstructure rather than surface profiling. Thus, simple and inexpensive processes can fabricate broadband wavelength-based DOEs for military, medical and biological applications.     

Molecular simulations of the structure and thermal transport of high alumina aluminosilicate molten core glass fiber

The atomistic structure and phonon transport in aluminosilicate glasses made via an interfacial mixing model of the Molten Core process were studied using molecular dynamics simulations. In the simulations, silica glass was brought in contact with different size alumina crystals (to afford core glasses with 4, 18, 24, 29, and 41 mole% alumina concentrations), followed by a melt‐quench process to enable mixing of the phases. The atomistic structure of the resulting glasses and radius of gyration calculations of resultant Al‐O‐Al connected clusters were evaluated. Variation in the 1‐dimensional thermal transport in each glass was also determined and showed that increased alumina concentration in the glasses resulted in increased transport of thermal energy. Results of the structural analyses showed a double peak in the Al‐Al pair distribution function, with the short‐distance peak indicative of edge‐sharing Al‐O‐Al‐O bonding and a longer distance peak of Al‐O‐Al bonding that is not indicative of edge‐sharing structures. The ratio of the first Al‐Al peak to the second Al‐Al peak varied inversely with the thermal transport behavior. An increased radius of gyration of Al‐O‐Al connectivity occurred with increasing alumina concentration, providing a mechanism for the increased thermal transport. Nanosegregation was also observed. Interconnectivity between Al ions created isolated Al‐O‐Al bonded clusters at low alumina concentrations with lower thermal transport than the high alumina glasses, whereas the latter showed a percolated network of Al‐O‐Al bonds that increased thermal transport.     

湿法玻璃粉体表面改性的研究

通过分级选取不同粒径的玻璃粉体,研究湿法对玻璃粉体表面改性的最佳条件,通过IR与TG-DSC分析,表明含20%水的乙醇溶液作为分散剂在70℃下进行实验得到的粉体表面改性效果较好,失重转变点出现在303℃(280～500目)与323℃(小于500目),较纯酒精243℃(280～500目)更高,终止点的温度也较高,其有机出峰也更为明显。同时研究表明粉体粒径粗细与表面改性结果成反比,随着粒径变小改性效果也更好,改性后的玻璃粉体在有机物质中分散比未改性玻璃粉体更为均匀,将改性后玻璃粉调配成浆料后的流动性下降,改性后的浆料流动时间均超过10 min。     

环氧树脂复合泡沫材料的制备研究

以缩水甘油酯环氧树脂(EP)、酸酐固化剂和空心玻璃微珠为主要原料,通过添加一定的活性稀释剂,高温固化制备了EP复合泡沫材料。研究了空心玻璃微珠的表面改性对复合泡沫材料性能的影响。结果表明,复合泡沫材料性能与空心玻璃微珠的表面性能密切相关,当EP/固化剂/稀释剂的质量比为100/120/15、KH-560改性的空心玻璃微珠用量为30份时,所制备的复合泡沫材料密度为0.826 g/cm3,压缩强度达115.8 MPa,比强度为140.2。