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Using coprecipitation method of assembling of the intercalation, by the design and optimization of reaction conditions, the five kinds of the organic ultraviolet absorber - mefenamic the acid (MFNA), 4,4 '- bis (2 - sulfonate styryl) biphenyl ( CBS-X), 4,4 '- (1,4 - phenylene bismethylene) bis nitrogen alkyl dimethyl benzoic acid (1,4-PMBADA), 4,4' - (1,3 - phenylene bis methylene) bis nitrogen alkyl the Zn2Al-LDHs dibenzoate (1,3-PMBADA) and 4,4 '- Stilbenedicarboxylic acid (SDCA) to their anionic form, embedded into the interlayer XRD, FT-IR, UV-Vis, TG-DTA methods such as organic UV absorber column stays hydrotalcite compound Zn2Al-LDH/MFNA, Zn2Al-LDH / 1,3-PMBADA, Zn2Al-LDH / 1 The ,4-PMBADA, Zn2Al-LDH/SDCA and Zn2Al-LDH/CBS-X the composition, structure and performance of the analytical characterization. The results show that, in total precipitation Intercalation Assembled reaction When selecting materials Zn / Al ratio of 2.0, the control total precipitation acidity about pH 8.6-9.0, the crystallization temperature of 80 ° C and the crystallization time of 24 h to obtain the organic ultraviolet absorber pillared hydrotalcite-high crystallinity, a single crystal phase, clear chemical composition to meet the composition formula of the hydrotalcite-based compound, the layer spacing D003 (nm) of 2.01 (Zn2Al-LDH/MFNA respectively), 1.85 ( Zn2Al-LDH / 1,3-PMBADA), 2.14 (Zn2Al-LDH / 1,4-PMBADA), 2.09 (Zn2Al-LDH/SDCA) and 1.97 (Zn2Al-LDH/CBS-X). Interlayer organic UV absorber (s) remain at their original structure, and interleaved between the layers in the form of a monolayer or bilayer directed orderly arranged, so that the main object and the interaction between the object and the object maximum LDHs more stable. The film via UV-Vis spectra show that the five organic UV absorbers pillared hydrotalcite collaboration capabilities with physical shielding and chemical absorption of ultraviolet light, has good UV shielding performance, and the visible light region transparency. When the organic UV absorber is inserted in the form of their anions LDHs interlayer, their ultraviolet absorption ability can be improved. Prepared five LDHs, Zn2Al-LDH / 1,3-PMBADA, Zn2Al-LDH / 1,4-PMBADA and Zn2Al-LDH/SDCA mainly ultraviolet UV-B band has a strong absorption, corresponding to the maximum absorption The peak wavelength of 305 nm, 306 nm and 298 nm, are less than 20% at the maximum absorption at a wavelength of the transmittance. Zn2Al-LDH/CBS-X the ultraviolet rays of the UV-A band of the strong absorption, corresponding to the maximum absorption peak wavelength of 348 nm, corresponding to the minimum transmittance of 12%. While the UV-A and UV-B band Zn2Al-LDH/MFNA have absorption peaks corresponding to the maximum absorption peak wavelength was 280 nm and 355nm, respectively, corresponding to a transmittance of 17% and 28%, respectively. Air oxidation reaction of castor oil organic UV absorbers pillared hydrotalcite compound almost no oxidation catalytic activity. TG-DTA analysis showed that the organic UV absorbers pillared hydrotalcite compound has a higher thermal stability, the decomposition temperature of the organic anion in the interlayer is reached above 400 ℃. The results show that coprecipitated interpolation layer assembly is the preparation of the organic ultraviolet absorbent pillared hydrotalcite compound simple and effective method, obtained LDHs have a good ultraviolet ray shielding effect, the visible areas of high transparency, low activity of the oxidation catalyst, and good thermal stability. and other characteristics, as a new generation of UV absorbing material, has a broad application prospects in sunscreen cosmetics and polymer materials.
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