塑料发光材料的研究

通过对长余辉蓄能发光粉(以下简称发光粉)的包覆处理,改善了塑料发光材料的发光效果。采用硬脂酸、二甲基硅油、硅烷偶联剂及SiO2溶胶分别包覆发光粉,发现对发光粉进行包覆处理后,塑料材料的发光效果均比未包覆的好;经二甲基硅油包覆发光粉制成的塑料发光材料的相对发光强度最高;以硬脂酸包覆的方法未能如其他包覆方法那样有效地阻断机器加工对发光粉发光性能的削弱。     

有机羧酸改性氮化铝粉体的抗水解性能

采用有机羧酸和PEG作为表面活性剂对工业AlN粉体进行表面改性处理,研究了改性前后AlN粉体的抗水解特性以及表面改性机制。研究结果表明,AlN表面与水分子发生化学反应,导致溶液的pH值迅速提高,表面包覆有机羧酸可有效地改善AlN粉体的抗水解性能;AlN粉体在水中浸泡48h后,氮含量基本保持不变,除了AlN晶相外,没有其他晶相出现,且改性粉体在高剪切应力的水基球磨介质中也保持较强的稳定性。     

长余辉发光海藻纤维的制备及性能研究

将稀土铝酸盐长余辉发光材料充分研磨,用硅烷偶联剂对其进行包覆处理,并测试长余辉发光材料包覆前后在分散液中的分散性能及红外光谱曲线。通过湿法纺丝,制备了偶联剂包覆前与包覆后的发光海藻纤维。在电镜下观察纤维的形态结构,测试纤维的力学性能和发光性能。结果表明:经偶联剂处理后的发光材料具有更好的分散性,且包覆后的发光粉末与海藻酸原液具有更好的相容性,纺丝后形成的发光纤维具有更均匀的外貌结构,其拉伸断裂强力更大,发光强度更强,余辉寿命更长。     

表面涂覆氮化铝粉末的抗水化性

研究了表面涂覆硬脂酸和吐温80对氮化铝粉末抗水化性能的影响。经过表面改性工艺处理的氮化铝粉末在20～60℃具有很好的化学稳定性,溶液pH值在9.88基本保持不变;改性处理的氮化铝粉末在水中长时间浸泡,X射线衍射分析表明其物相为AlN相。通过表面改性工艺在氮化铝粉末表面包裹一层有机化合物,能有效地抑制氮化铝与水的反应,阻碍水分子向氮化铝粉末表面侵蚀,提高氮化铝粉末在潮湿环境的抗水化能力。     

聚丙烯酰胺改性的碱土铝酸盐发光材料的制备与性能研究

在温度为80℃、pH值为1~2的酸性条件下制备出了聚丙烯酰胺改性的SrAl2O4:Eu2+,Dy3+发光材料。采用红外吸收光谱、热失重和荧光光谱等对改性的发光材料进行了表征和性能测试,并通过pH值测定结果和沉降实验对改性的发光材料的耐水性和分散性进行了测定。结果表明,改性后的发光材料中包含了聚丙烯酰胺改性剂,发光强度降低了约2%,但对其发光性能无太大影响,经聚丙烯酰胺改性后,发光材料的耐水性和分散性得到明显地改善。     

长余辉发光材料在涂料中的应用

长余辉发光材料是一类吸收激发光能并贮存起来,光激发停止后再把贮存的能量以光的形式慢慢释放出来,可持续几个甚至十几个小时发光的材料.长余辉材料表面处理后应用到涂料中,可制备出耐久性优异、施工方便的发光涂料.发光涂料最重要的性能是余辉性能,其余辉亮度和隐没时间主要同长余辉发光材料的类型和加量、漆膜厚度、激发光源等因素相关.进一步探讨了发光材料对涂料贮存稳定性和耐久性的影响.     

聚苯乙烯/稀土复合发光材料的制备及其性能研究

采用硅烷偶联剂对稀土发光材料进行表面改性。将苯乙烯、改性后的稀土发光材料和引发剂偶氮二异丁腈加入到聚合反应装置中,进行原位乳液聚合,制备聚苯乙烯(PS)/稀土复合发光材料。红外光谱、热失重和显微镜分析表明,PS已经成功接枝到稀土发光材料表面,并以片状均匀地包覆于稀土发光材料表面。通过测试PS/稀土复合发光材料的表面接触角,发现PS/稀土复合发光材料有着优异的耐水性能。荧光光谱分析表明,乳液聚合过程中PS/稀土复合发光材料没有改变稀土发光材料的基质,PS/稀土复合发光材料的发光中心与稀土发光材料的相同。     

马来酸酐表面包覆SrAl2O4:Eu2+,Dy3+发光粉及其耐水性能

以马来酸酐为原料,采用界面配位化学法制备出表面包覆有马来酸酐的SrAl2O4:Eu2 ,Dy3 发光复合粉体.运用酸度计测量复合粉体在水中的pH值.通过配位多面体生长基元理论确定包覆的关键因素是溶剂、反应温度、溶液pH及反应时间,探讨了这些参数对包覆后发光粉耐水性能的影响.结果表明:优化的包覆条件为:以氯仿为溶剂,反应温度为(35±5)℃,溶液pH=8.5,反应时间为6 h.在此条件下,在SrAl2O4:Eu2 , Dy3 表面易于形成均匀致密连续的马来酸酐膜层,而且,复合粉体的耐水性能最优.     

蓄能发光功能涂料研究及其应用

介绍了蓄能发光涂料中所用发光材料的种类与性能特点，阐述了目前稀土铝酸盐长余辉蓄能发光材料的研究成果及作为涂料添加剂的表面改性处理；列举了蓄能发光涂料在建筑装饰、消防安全等领域的应用，对其存在的问题和发展趋势进行了探讨；同时简述了相关的研究。     

表面活性剂后处理对YAG∶Ce~(3+)荧光粉发光特性的影响

采用固相法制备YAG∶Ce3+黄色荧光粉,以油酸、聚乙二醇、十二烷基磺酸钠和十二烷基硫酸钠等表面活性剂作为后处理剂,考察其种类、浓度和性质等对荧光粉发光性能的影响,进一步对浸泡温度以及浸泡时间等工艺条件进行了对比研究,并通过荧光光谱和扫描电子显微镜等手段对处理前后YAG∶Ce3+荧光粉的发光性能、表面形貌和老化性能等方面进行了表征和分析。结果表明,YAG∶Ce3+荧光粉的最佳后处理工艺条件为:十二烷基硫酸钠较为理想,经2.4%十二烷基硫酸钠处理后,YAG∶Ce3+荧光粉的发光强度约提高8.4%,浸泡温度为50℃,浸泡时间为60 min。     

Preparation and luminescence of SrAl2O4: Eu2+,Dy3+ phosphors coated with maleic anhydride

In this paper, maleic anhydride is directly coated on the surface of SrAl₂O₄: Eu²⁺, Dy³⁺ (SAO‐ED) phosphors by an interfacial coordination chemistry method. Fourier transform infrared spectroscopy (FTIR), X‐ray photoelectron spectra (XPS), X‐ray diffraction (XRD), and scanning electron microscopy (SEM) methods are used to characterize the coating. The experimental result shows that a dense coating layer is consisting of maleic anhydride coordination with metal ions on the surface of the phosphors and the coating process does not destroy the crystal structure of the phosphors. It is also found that the introduction of maleic anhydride does not change the excitation and emission spectra of SAO‐ED phosphors, but decreases the luminous intensity, which is verified by the photoluminescence (PL) measurement. Afterglow delay curves show that the initial brightness of coated SAO‐ED phosphors decreases, but the afterglow decay rate of coated phosphors is slower than that of uncoated phosphors after they both are immersed into water for one month. This indicates that the coating layer protects the phosphors and the crystal structure of coated phosphors in water was not destroyed.     

片状铜粉化学镀锡的工艺研究

采用次磷酸钠作还原剂,在片状铜粉表面化学镀锡,得到片状锡包铜粉。研究了镀液pH、温度、还原剂、稳定剂以及主盐浓度等对锡包铜粉性能的影响规律,研究了锡包铜粉的成分和表面形貌。结果表明:通过控制工艺参数可以获得镀覆质量好,且具有很好导电性和低松装密度的片状锡包铜粉产品。     

A study of the surface and luminescence properties of ZnS : Mn<Superscript>2+</Superscript> nanosized phosphors

The influence of the stabilizer and thermal treatment on the luminescence and surface properties of ZnS: Mn²⁺ nanosized phosphors has been studied. It has been found that ammonium polyacrylate is the optimal stabilizer for the use in the preparation of phosphors with nanoparticles that exhibits the highest brightness without applying thermal treatment. Analysis of the correlation between the luminescence spectral bands and the content of active surface adsorption sites has demonstrated that the model of active sites previously developed for the surface of zinc sulfide phosphors with large particles can also be used for nanosized phosphors.     

不同碳链长度饱和脂肪酸基铝锆偶联剂对夜光粉的表面修饰

为扩展夜光粉的应用领域,以不同碳链长度的饱和脂肪酸(辛酸、月桂酸、硬脂酸)为有机功能配体制备了3种新型铝锆偶联剂(CA),并对夜光粉(SrMgAl4O8:Eu2+、Dy3+)进行了表面修饰,用ATR-FTIR和接触角表征了样品表面性质,用水中pH和电导率的变化测定其耐水性,用TG表征了不同CA、原样及改性样的热失质量行为,并以此首次提出计算不同CA在夜光粉表面包覆量的方法及其结构模型。结果表明:随着CA中饱和脂肪酸碳链长度的增加(由辛酸到硬脂酸),夜光粉表面包覆量由13.41%降为6.53%,月桂酸基铝锆CA改性样具有最佳的耐水性和相容性。     

Nanoscale ZnO and Al-Doped ZnO Coatings on ZnS:Ag Phosphors and their Cathodoluminescent Properties

Blue-emitting ZnS:Ag phosphors were coated with nanoscale zinc oxide (ZnO) and Al-doped ZnO (AZO) and the cathodoluminescence (CL) performance of the coated phosphors was investigated. The nanoscale coating was obtained by controlling the hydrolysis reaction of ZnCl₂ alcoholic solution using diethylamine as a gradual OH⁻ former, and Al doping was performed to increase the electrical conductivity of ZnO. The coatings were composed of either nanosized particles or a continuous nano layer, and the AZO-coated phosphor had a more uniformly covered surface. The coated phosphors exhibited improved aging behavior under CL excitation and the AZO coating was more effective at suppressing the degradation, possibly due to its uniformity and high conductivity.     

铅板无氰仿金镀工艺研究

用扫描电镜和能谱分析方法,研究了铅板上仿金镀层组成颜色及表面形貌,确定了铅板上仿金电镀的工艺流程及最佳工艺参数.结果表明,以光亮镀镍打底,仿金镀的Jκ=1.2 A/dm2;pH=8.5～9.3;θ=20～35℃;t=1～4 min的条件下,能够获得仿金色镀层,且镀层表面平整,结晶细致,无裂痕、孔隙,镀层质量较好.     

Calcium sulphate as pigment for improved functional properties of coated paper

In the last few years, interest and demand of high bright paper have forced paper manufacturers to think new ways to improve brightness and whiteness of coated paper. Pigment coating is widely used to enhance the optical properties such as brightness, whiteness, and gloss of paper and paperboard. These optical properties are the most important for end user and also determine the final cost of coated paper. Calcium sulphate has inherent better optical properties compared to other conventional pigments for example ground calcium carbonate, precipitated calcium carbonate and kaolin clay. The present study was carried out with an aim to synthesize calcium sulphate using waste procured from phosphoric acid industry and to study its impact on the rheology of coating color as well as optical properties of coated paper. Addition of calcium sulphate improved the water retention property of coating color which can be helpful for improving the machine runnability. The results also revealed that calcium sulphate can be used as a pigment to produce coated paper of high brightness and whiteness. The brightness and whiteness of the coated paper were improved 4 and 15 points, respectively by using 50 parts of calcium sulphate as a pigment replacing clay from the coating formulation. The surface strength in terms of IGT pick value of coated sheets was found significantly comparable using calcium sulphate as pigment. The print gloss results were observed analogous with matt grade coated paper.     

ZnO:Al包覆CaSiO3:(Pb,Mn)荧光粉

利用溶液中的共沉淀反应制备了CaSiO3:(Pb,Mn)红色光致荧光粉.以Zn(NO3)2·6H2O和AlCl3·6H2O为原料,借助CO(NH2)2水解反应,用化学均相共沉淀法和热处理工艺在荧光粉表面包覆一层ZnO:Al透明导电薄膜.对包覆前后的样品进行了X射线衍射结构分析、光致荧光分析、透射电镜形貌观察及电阻测量.结果显示:包覆后荧光粉的电导率显著提高,但光致荧光峰的位置和强度无明显变化.综合考虑包覆对荧光粉电阻率和荧光性质的影响,优化包覆条件和热处理条件为:n(Zn)/n(Ca)=10%,n(Al)/n(Zn)=5%,75℃水解1 5 h;包覆后的样品在500℃热处理45 min.     

Enhanced thermal stability of CaAlSiN3:Eu2+ phosphors by superficial carbon modification

To satisfy increasing stringent application requirements for high power wLEDs, we propose a superficial carbon modification method to enhance thermal stability of red-emitting CaAlSiN₃:Eu²⁺ phosphor via carbon coating by mechanical mixing and thermal post-treatment at high temperature under N₂-H₂ atmosphere. The modifications on the crystal surface include (a) elimination of amorphous phase, (b) introduction of carbon and (c) inhibition of the oxidation of Eu²⁺. During the whole processing, the route of carbon and its effects on the crystal structure and luminescence properties are investigated by XPS, TEM, SEM, Raman spectra and TG-DSC analysis. After superficial carbon modification, the thermal quenching characteristic is improved by 5.7%, and the relative brightness decays more slowly during the aging test, which means that the superficial carbon modified samples still maintain good luminescence performance at high temperature and have superior performance for long-term applications. All above indicate that the superficial carbon modification method is a promising application to enhance the thermal stability for analogous Eu²⁺-activated nitride phosphors.     

聚苯胺/聚乙烯醇微乳液导电涂料的研制及其性能的测试

采用氧化聚合方法合成可溶性的聚苯胺/聚乙烯醇(PAn/PVA)复合导电涂料.研究了反应体系中聚苯胺的含量、反应时间、温度及酸浓度对导电涂料电导率的影响,确定了较佳的聚合反应条件,同时对其稳定性、导电性、力学性及其表面结构等进行了测试.结果表明,PAn/PVA导电涂料稳定性好,在空气中放置80h电导率无明显变化,涂料涂层的电导率最高可达4.57s/cm,加入环氧树脂可明显改善涂层的附着力.