钒酸铋颜料

综述了钒酸铋颜料的性能、用途及其制备方法。     

钒酸铋颜料的研制

通过两种合成方法即粉末煅烧法、水溶液沉淀法的具体实验过程来制得钒酸铋颜料，并结合差热分析曲线、X射线衍射图和扫描电镜（SEM）照片来分析研究颜料合成的最佳工艺条件，进行产物的物相鉴别和观察产品的微观形貌及探讨颜料合成的机制。     

巴斯夫钒酸铋颜料涨价

巴斯夫日前宣布，自7月1日起，在全球范围内对公司出产的所有类型钒酸铋颜料附加费调高到9．5美元。这主要是受到了钒铅矿石涨价的影响。巴斯夫钒酸铋颜料主要用于涂料、油墨和塑料领域。     

钒酸铋黄色颜料的合成技术进展

钒酸铋(BiVO4)黄色颜料是一种无毒、品质优良的新型无机颜料,其发展前景非常广阔。传统的合成方法分为固相法和液相法,固相法在改变颜料品质方面受限制较多,而液相法则较少。近几年科研人员开发出的液相法有:液相沉淀法,水热合成法,微波辅助加热法,微乳液法,络合法,包覆法等。文章详细介绍了这些方法的具体过程,可为有关人员作为参考。     

钒酸铋颜料合成和性能的研究

采用液相沉淀法合成了钒酸铋颜料，可作为铬黄、镉黄颜料的换代品。研究了该颜料的光学性能、表面形态和粒度分布。讨论了沉淀反应的温度和pH，以及回流温度对颜料性能的影响。     

耐高温钒酸铋黄色颜料的制备

为了提高钒酸铋(BiVO4)黄色颜料的耐高温性,利用正硅酸乙酯(TEOS)的水解反应,在BiVO4表面形成SiO2膜,使钒酸铋黄色颜料经过1 000℃的高温煅烧,依然颜色鲜艳。通过实验确定了制备耐高温钒酸铋黄色颜料的适宜工艺条件:在室温下,TEOS浓度为0.14 mol/L,反应2 h并陈化约20 h,十二烷基苯磺酸钠(DBS)质量分数为0.4%,包覆2次SiO2。采用红外光谱仪、X射线衍射仪、差热分析仪对产品进行了表征,并得出结论:复合颗粒红外光谱显示,表面存在SiO2标准谱图中的特征吸收峰;X射线衍射证实SiO2以四方晶相包覆于BiVO4表面;差热分析结果表明,包覆的SiO2起到了防止BiVO4烧结的作用。     

均相反应法制备钒酸铋颜料

以Bi(NO3)3?5H2O和NH4VO3为原料,采用均相反应法制备不同形貌的BiVO4粉末,考察了V/Bi摩尔比、pH值、反应温度、均相反应器转速等因素对BiVO4粒度、形貌和色度的影响,对BiVO4产物进行了表征. 结果表明,均相反应有利于制备粒度均匀、形貌均一的BiVO4粉末,在V/Bi=1(摩尔比)、pH=7、反应温度105℃、反应时间6 h、均相反应转速60 r/min的条件下可得到理想的BiVO4颜料产品,添加表面活性剂可获得更多形貌的BiVO4,有利于其应用.     

包核法制备钒酸铋颜料的研究

简述了包核颜料的基本原理，合成了以二氧化硅为内核的包核型钒酸铋颜料，考察了不同浓度的SiO2内核对颜料性能的影响，并用光谱、CIELAB系统、SEM、XRD等手段对其性能进行了表征。结果表明：随SiO2浓度的变化，包核颜料出现了一个性能最佳点；反应液中的SiO2浓度在4．512～24．875mmol／L时，所得产物的分散性及光学性能高于非包核型产物。     

钒酸铋掺杂体系的研究进展

介绍了稀土元素、过渡元素、碳族元素和其它元素的钒酸铋掺杂体系,并对未来的发展方向做出展望。     

Bismuth sodium titanate based lead-free ultrasonic transducer for microelectronics wirebonding applications

Bismuth sodium titanate based lead-free piezoelectric ceramic 0.885(Bi_1/2Na_1/2)TiO₃–0.05(Bi_1/2K_1/2)TiO₃–0.015(Bi_1/2Li_1/2)TiO₃–0.05BaTiO₃ (BNKLBT-1.5) rings (OD = 12.7mm, ID = 5.1 mm and 2.3 mm thick) were fabricated and characterized. Four ceramic rings were sandwiched between front and back metal plates to form a pre-stressed piezoelectric sandwich transducer and used as the driving element of an ultrasonic wirebonding transducer and the performance of the transducer was evaluated. The BNKLBT-1.5 transducer, when fitted with titanium front and back plates, was found to have axial vibration comparable to that of PZT transducer thus showing that BNKLBT-1.5 has the potential to be used in fabricating lead-free ultrasonic wirebonding transducers.     

The temperature dependence of the absorption edge in Bismuth vanadate crystals (BiVO4)

The temperature dependence of the absorption edge in bismuth vanadate single crystal was measured, and it has turned out that the absorption edge shifts towards the longer wave-length side with increasing temperature.     

Protective heat-resistant lead-free enamels for copper

Based on the R₂O - CaO - BaO - B₂O₃ - Al₂O₃ - SiO₂ system, the areas of glass formation are defined and the composition used as a glass matrix for heat-resistant enamels is determined. The effect of Fe₃O₄, Co₂O₃, and MnO₂ additives on adhesion strength and heat stability is investigated. The optimal compositions are identified. The dependence of the structure and phase composition of enamel coatings on the content of the specified additives is established.     

国内外导电胶的发展现状

由于铅对人体及环境有害,使得铅锡焊料的使用受到了限制.目前无铅焊料和导电胶被认为是理想的铅锡焊料替代品.本文介绍国内外无铅连接材料的最新进展,重点论及作为环境友好型的无铅连接材料的导电胶及其组成、应用和最新进展.     

Soft-Chemistry Synthesis and Characterization of Bismuth Oxyfluorides and Ammonium Bismuth Fluorides

Two bismuth oxyfluorides, BiOF and BiO_0.5F₂, have been prepared by soft chemistry. These two compounds are of interest for application as new type of positive electrode active materials in secondary lithium battery. BiOF was obtained directly from the fluorination of Bi₂O₃ by a saturated aqueous solution of NH₄F. BiO_0.5F₂ was obtained by the hydrolysis of β-NH₄BiF₄ at 70°C. The ammonium bismuth fluoride β-NH₄BiF₄, which is a new orthorhombic form of NH₄BiF₄, was obtained by reacting BiF₃ in a saturated aqueous solution of NH₄F. Two other ammonium bismuth fluorides, (NH₄)_0.5BiF_3.5 and NH₄Bi₃F₁₀, were also prepared by annealing β-NH₄BiF₄ at a relatively low temperature under inert atmosphere. The existence of the fluorite (NH₄)_0.5BiF_3.5 is reported for the first time in this paper.     

Polymer nanocomposites for bone tissue substitutes

Following the quest for new composite biomaterials for bone tissue engineering, this work presents the processing of new nanocomposite made of polycaprolactone matrix and wollastonite particles. Wollastonite nanopowder was obtained by thermal treatment of polymethyloxosilane resin mixed with silica and calcium hydroxide. Bioactive character of the ceramic nanopowder was verified in simulated body fluid (SBF). The apatite formation on wollastonite grain surface after immersion in SBF was observed. Basic mechanical properties of the samples containing various amount of ceramic nanoparticles have been examined. It was shown that the presence of small amount of wollastonite nanoparticles (0.5–1.0 wt%) improves significantly the Young's modulus, tensile strength, and work-of-fracture of polymer matrix composite. Increased content of ceramic nanoadditive (>2%) in nanocomposites resulted in degradation of their mechanical characteristics.     

含铅颜料代用品的开发进展

含铅颜料是主要的铅污染源。介绍了国外含铅颜料代用品的开发情况,它们是新型无毒防锈颜料、正确调整的有机颜料、金红石型混相颜料、钒酸铋黄、稀土颜料和安全黄。     

色漆制造及通用色浆

对色漆生产的几种工艺方式作了比较 ,说明通用色浆的经济性、配套性以及在仓贮、调色等方面的突出优点。