UV photo‐stabilization of tetrabutyl titanate for aramid fibers via sol–gel surface modification

Tetrabutyl titanate was used as sol–gel precursor of a nanosized TiO₂ coating to improve the photo‐stability of aramid fibers. The nanosized TiO₂ coating was characterized by XRD and XPS. The influence of the TiO₂ coating on photo‐stability of aramid fibers was investigated by an accelerated photo‐ageing method. The photo‐stability of aramid fiber showed obvious improvement after coating. After 156 h of UV exposure, the coated fibers showed less deterioration in mechanical properties with the retained tensile strength and elongation at break greater than 36 and 50% of the original values, respectively, whereas the uncoated fibers degraded completely and became powdery. SEM analysis showed no significant surface morphological change on the coated fiber after the exposure, while some latitudinal crack fractures appeared on the uncoated aramid fiber. The effect of the nanosized TiO₂ coating was also well demonstrated by examining the difference of distributions of C1s in XPS deconvolution analysis on the surface of uncoated/coated fibers with increasing UV exposure time. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3113–3119, 2007     

Phase evolution and thermophysical properties of high-entropy RE2(Y0.2Yb0.2Nb0.2Ta0.2Ce0.2)2O7 oxides

Pursuing novel thermal barrier–coating materials with lower thermal conductivity and high-temperature stability can simultaneously improve the working efficiency and service temperature of a gas turbine. In this study, a series of high-entropy RE₂(Y_0.2Yb_0.2Nb_0.2Ta_0.2Ce_0.2)₂O₇ (RE = La, Nd, Sm, Gd, Dy, and Er) oxides were prepared though solid-state reaction. Through tuning the rare-earth cations, an order–disorder transition occurs from certain partially ordered weberite structure (C222₁) to disordered defective fluorite structure (Fm$\overline{3}$m). All the high-entropy RE₂(Y_0.2Yb_0.2Nb_0.2Ta_0.2Ce_0.2)₂O₇ oxides possess low thermal conductivity in the range of 0.91–1.34 W m⁻¹ K⁻¹ at room temperature, which can be attributed to increased lattice anharmonicity and disorder, resulting in additional phonon scattering. Herein, we proved that the incorporation of heterovalent cations at B-sites in high-entropy A₂B₂O₇ crystals is an effective strategy to reduce the thermal conductivity without compromising the decrease of oxygen vacancy. Moreover, the high-entropy RE₂(Y_0.2Yb_0.2Nb_0.2Ta_0.2Ce_0.2)₂O₇ oxides show the relatively higher thermal expansion coefficients of 10.3–10.7 × 10⁻⁶°C⁻¹ and excellent phase stability at elevated temperatures.     

1101汽车底盘专用漆的研制

研制了性能优异的汽车底盘专用漆,介绍了该漆的生产配方及工艺流程,列举了该漆的性能指标及检测结果,讨论了影响该漆性能、质量的各种因素.     

水性涂料漆膜防霉效力测试若干问题的探讨

介绍了防霉剂防霉效力不同的测试方法以及国内外漆膜防霉性能测试的相关标准，提出了水性涂料漆膜防霉效力测试应采用人工环境长霉试验方法，探讨了国内外水性涂料防霉标准及测试方法中有待解决的问题。     

纳米SiO_2表面改性及其在水性涂料中的应用

通过正交实验筛选出最隹分散工艺,将改性后的纳米级多孔SiO2加入到水性苯丙乳液涂料中配制出水性纳米涂料,并对其涂料进行了性能测试。     

Surface properties of fluorinated hybrid coatings

A commercial perfluoropolyether containing alkoxysilane functionalities was employed to prepare organic–inorganic hybrid coatings by using the sol‐gel process in the presence of tetraethoxysilane. Contact angle analysis revealed a strong hydrophobic and oleophobic character of the coatings almost independently from the molecular weight of the starting fluorinated oligomer. Surface tension values were in the range of 14–16 mN/m, suggesting a preferential segregation of fluorinated segments onto the surface of the coating. Atomic force microscopy showed the presence very smooth surfaces permitting to neglect the contribution of the surface roughness to wettability. Friction coefficient values were markedly lower with respect to the value of uncoated glass substrate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1483–1488, 2006     

纳米TiO2抗菌涂料研究进展

介绍了纳米TiO2抗菌涂料的抗菌机理、制备方法和应用现状，并对其研究进行了展望。     

乳液共混法制备水性阻尼涂料

通过乳液共混法将不同Tg的丙烯酸酯乳液进行共混,并加入填料和助剂配制成涂料。动态力学谱结果表明,当乳液按照丙烯酸乳液与苯乙烯-丙烯酸酯乳液比为40∶10共混时,阻尼温域得以拓宽,并达到Tg与室温一致的使用温域。     

现代汽车非金属部件的修补涂装

介绍了汽车塑料件的识别、预处理和修补涂装。     

等离子喷涂羟基磷灰石涂层

羟基磷灰石由于具有优良的生物性能，被广泛应用于生物材料领域，而等离子喷涂制备羟基磷灰石涂层是应用最为广泛的制备方法之一。在综合国内外献的基础上，本从羟基磷灰石的本征性能、喷涂工艺的影响、结合强度和梯度涂层等方面进行综述。