以硅溶胶为主要成膜物的水性木器透明底漆的研究

研究了硅溶胶凝胶的影响因素,选择匹配的高分子聚合物,对硅溶胶胶粒进行绑缚作用,协助硅溶胶成膜降低其刚性,考察其他助剂的协同作用,发挥出硅溶胶成膜后的特性,配制的水性木器涂料透明底漆具有硬度高、干速快、硬度建立快、初期抗压性好、耐水性优、附着力好、打磨性好等优势.     

透明裂纹釉影响因素的探究

本项目以较好的透明裂纹釉配方为基础,考察其釉料组成、工艺参数和烧成制度等对釉面效果的影响。实验结果证明：较好的组成范围是,钠长石为70-78wt.%,高岭土1-3wt.%,石英12-20wt.%,石灰石6-12wt.%;烧成温度为1290℃,保温30 min,冷却速度20℃/min;釉层厚度为0.8~1.3 mm,球磨时间是20 min。所得样品釉面光滑平整、透明度较好,裂纹也具有较好艺术效果。     

丙烯酸透明粉末涂料在汽车车身罩光方面的应用

分析了丙烯酸粉末涂料用于汽车车身罩光时需要解决的若干问题,如降低固化温度、提高涂层抗冲击性能、提高涂层表面光滑平整度、提高涂层耐候性能、提高与底漆的配套性能等。针对不同问题,给出了相应的解决工艺。     

高强、高透明、紫外屏蔽细菌纤维素复合膜的制备与性能

本研究以细菌纤维素（BC）为主要原料,通过折射率匹配原理制备具有高透明度的聚乙烯醇（PVA）/BC复合膜,并进一步与环氧树脂（EP）复合,减小复合膜表面的粗糙度,从而降低其雾度,制备了高强、高透明且疏水的PVA/BC/EP复合膜。结果表明,PVA/BC/EP复合膜比纯BC膜具有更光滑的表面和更致密的结构,雾度低,光透过率达90%;由于PVA、BC和EP之间存在相互作用,复合膜的拉伸强度高达177.1 MPa,表面疏水性也得到明显提高。引入碳量子点可赋予复合膜良好的紫外光屏蔽性能,为高强度、高透明度及紫外屏蔽多功能膜材料的应用提供了新思路。     

Synthesis and luminescence characterization of Pr3+, Gd3+ co-doped SrF2 transparent ceramics

Pr³⁺, Gd³⁺ co-doped SrF₂ transparent ceramic, as the potential material for visible luminescent applications, was prepared by hot-pressing of precursor nanopowders. The microstructure, phase compositions, and in-line transmittance, as well as the photoluminescence properties were investigated systematically. Highly optical quality Pr,Gd:SrF₂ transparent ceramic with nearly pore-free microstructure was obtained at 800°C for 1.5 hours. The average in-line transmittance of the x at.% Pr, 6 at.% Gd:SrF₂ (x = 0.2, 0.5, 1.0, 2.0) transparent ceramics reached to 87.3 % in the infrared region. The photoluminescence spectra presented intense visible light emissions under the excitation of 444 nm, the main intrinsic emission bands located at 483 and 605 nm, which were attributed to the transitions of Pr³⁺: ³P₀ → ³H₄ and ¹D₂ → ³H₄, respectively. With the co-doping of Gd³⁺ ions, the emission intensity of the Pr:SrF₂ transparent ceramic was greatly enhanced. All the emission bands of x at.% Pr, 6 at.% Gd:SrF₂ transparent ceramics exhibited the highest luminescence intensity with the 1.0 at.% Pr³⁺ doping concentrations, whereas the lifetimes decreased dramatically with the Pr³⁺ doping contents increasing from 0.2 to 2.0 at.% due to its intense concentration quenching effect. The 1 at.% Pr, 6 at.% Gd:SrF₂ transparent ceramic is a promising material for visible luminescent device applications.     

Er3+-doped CaF2 polycrystalline ceramic with perfect transparency for mid-infrared laser

Er³⁺-doped CaF₂ transparent ceramics are promising mid-infrared gain materials because of their utra-low phonon energy as well as excellent physical, chemical, and optical properties. However, existing hot-pressed and hot-formed CaF₂ ceramics are very difficult to be used in practical applications due to residual pores and weak polycrystallization, respectively. Here, we developed the high quality Er³⁺-doped CaF₂ transparent polycrystalline ceramic by single crystal ceramization. The sample exhibits obvious polycrystalline structure, good mechanical properties, perfectly transmittance, and excellent mid-infrared performance, which provides significant and wide-ranging opportunities for advanced mid-infrared gain materials.     

Processing of CaLa2S4 infrared transparent ceramics: A comparative study of HP and FAST/SPS techniques

The densification of CaLa₂S₄ (CLS) powders prepared by combustion method was investigated by the use of Field-Assisted Sintering Technique (FAST) and Hot Pressing (HP). CLS powders were sintered using FAST at 1000°C at different pressures and heating rates and sintered by HP under 120 MPa from 800°C to 1100°C for 6 hours with a heating rate of 10°C/min. Comparison of both techniques was further realized by use of the same conditions of pressure, dwell time, and heating rate. Complementary techniques (XRD, SEM-EDS, density measurements, FTIR spectroscopy) were employed to correlate the sintering processes/parameters to the microstructural/compositional developments and optical transmission of the ceramics. Both sintering techniques produce ceramics with submicrometer grain size and relative density of about 99%. Nevertheless, HP is more suitable to densify CLS ceramics without fragmentation and also reach higher transmission than FAST. Transmission of 40%–45% was measured out of a possible maximum of 69% based on the Fresnel losses in the 8-14 μm window when HP is applied at 1000°C for 6 hours under 120 MPa. In both techniques, ceramics undergo reduction issues that originate from graphitic sintering atmosphere.     

Influence of composition and microstructure on transparency and diffusivity in ion-exchangeable spinel glass-ceramics

Ion-exchangeable, transparent spinel glass-ceramics are presented and discussed here for the first time. To retain transparency with increasing crystallinity, spinel glass-ceramics must have uniform crystallization of small (~9 nm) crystallites, not large spherulitic structures comprised of small crystallites. To obtain such a uniform microstructure, the amount of total nucleating agents (ZrO₂ + TiO₂) in the precursor glass composition must be greater than 5 mol%. With small changes in composition and significant differences in microstructure, the demarcation between transparent and opaque glass-ceramics is distinct as is the decrease in K diffusivity during ion-exchange from the transparent (14.7 microns²/h) to the opaque (11.2 microns²/h) compositions. Understanding how to retain transparency during ceramming and increase diffusivity during chemical strengthening is critical in designing materials for many real-world applications. Ion-exchangeable, transparent spinel glass-ceramics are presented and discussed here for the first time. To retain transparency with increasing crystallinity, spinel glass-ceramics must have uniform crystallization of small (~9 nm) crystallites, not large spherulitic structures comprised of small crystallites. To obtain such a uniform microstructure, the amount of total nucleating agents (ZrO₂ + TiO₂) in the precursor glass composition must be greater than 5 mol%. With small changes in composition and significant differences in microstructure, the demarcation between transparent and opaque glass-ceramics is distinct as is the decrease in K diffusivity during ion-exchange from the transparent (14.7 microns²/h) to the opaque (11.2 microns²/h) compositions. Understanding how to retain transparency during ceramming and increase diffusivity during chemical strengthening is critical in designing materials for many real-world applications.     

Effect of porosity and hexagonality on the infrared transmission of spark plasma sintered ZnS ceramics

Tailoring phase transition and microstructural evolution during sintering is crucial for the fabrication of ZnS ceramics transparent to infrared (IR) radiation. Herein, we have described the phase transition, microstructure, and related IR transmission of spark-plasma-sintered ZnS ceramics in terms of sintering temperature and pressure. The pore characteristics of spark-plasma-sintered ZnS ceramics were evaluated using Mie scattering theory. Changes in hexagonality and residual pore characteristics of the microstructure affected IR transmission of the sintered specimens. High temperature and pressure condition of SPS were found to increase excessive hexagonal phase (>20%), mainly contributing to a transmittance decay in the range 2–4 μm.     

环保型透明双组分改性聚氨酯胶黏剂的研究

报道了一种无溶剂、双组分、透明环氧改性聚氨酯胶黏剂,利用红外光谱法跟踪探讨了合成机理,分析了各基团之间的化学反应及其产物随时间的变化。结果表明:改性后聚氨酯的许多性能得到改进;在最佳原料配比及适宜的实验条件下,产品黏度适中,流动性好,性能稳定,储存期长;在m(合成环氧改性聚氨酯)∶m(固化剂)=5∶3的条件下,室温表干时间约45 min,剪切强度大于19 MPa,产品为韧性,耐溶剂、耐温性优良,固化过程中不起泡,用于粘接及灌封时美观。