| Organic pigments possess the virtue of fresh color, bright hue, abundant varieties, whole chromatogram, excellent dispersion ability and they are widely used in various fields such as printing inks, paints, coatings and plastics. Unfortunately, most organic pigments always suffer poor thermostability and photostability and are therefore limited to use. So it is vital to synthesize pigment with high thermostability and photostability. Layered double hydroxides (LDHs) are a calss of anionic lamellar functional materials. They have been attracted considerable attention due to their unique crustal structure and physical and chemical properties. The kind and amount of the metals constituting the host layers of LDHs and interlayer anions, which can be exchanged out, can be changed in a wide range. LDHs have widespread applications as anion-exchangers, adsorbents, catalysts or catalyst precursors, as optical, electrical and magnetic functional materials, and additives in polymers in the fields of industry, agriculture and so on. In this dissertation, we synthesized a kind of inorganic-organic complex pigments which may by intercalating several dye anions into the interlayer of LDHs in order to improve the thermal stability and light fass of the dye anions. Due to the variety and amount of anions in the interlayer of LDHs can be controled, a series of different colored pigments can be prepared by modulating the kind and amount of the intercalated dye anions. In recent years, a number of layered double hydroxides films have been fabricated through different methods. Therefore colored functional films can be synthesized by intercalating dye anions into the interlayer galleries of films of LDHs. Such films can serve as paints which impart color and also provide protection for the substrate.The details are shown below:1. Several single dye anions intercalated inorganic-organic complex pigments had been synthesized by ion-exchange method or coprecipitation method. Acid mordant yellow 10 and acid green 28 anions intercalated LDHs was prepared by ion-exchange method using ZnAl-NO3-LDHs as a precursor which was prepared with separate nucleation and aging steps method. Thus inorganic-organic complex pigments with yellow and green color were obtained. Acid blue 129 anion intercalated inorganic-organic complex pigments with blue color was synthesized by coprecipitation method. The FT-IR and TG-DTA results show that there are host-guest interactions between the host ZnAl-LDHs layers and the guest dye anions and the temperatures for oxidative thermal decomposition of dye anions are enhanced a lot after intercalated into the interlayer of LDHs. Thermal aging tests indicate that the thermal stability of the inorganic-organic complex pigments are higher than that of the bare dyes. Inorganic-organic complex pigments also possess better light fastness than the corresponding dyes shown by photoaging tests. There2. Acid blue 25 and acid yellow 25 dye anions cointercalated supramolecular pigments was synthesized by coprecipitation method. The characterization results show that acid blue 25 and acid yellow 25 anions were cointercalated into the interlayer of ZnAL-LDHs. As the increasing of the molar ration of acid blue 25 in the reaction stuff, the intercalated amount of acid blue 25 increased, the layered structure of the complex pigments become much better and the color of the complex pigments changed gradually. The FT-IR and TG-DTA results show that there are host-guest interactions between the host ZnAl-LDHs layers and both of the guest dye anions and the oxidative thermal decomposition temperatures of the two dye anions are improved a lot after intercalated into the interlayer of LDHs. Thermal aging tests and photo aging tests indicate that the thermal stability and light fastness of the inorganic-organic complex pigments are higher than those of acid blue 25 and acid yellow 25.3. ZnAl-NO3-LDHs film precursors were fabricated on aluminum sheet and anodic alumina substrates by in-situ growth method. Acid yellow 49 and 25 anions were intercalated into the ZnAl-LDHs/Al film and acid blue 25 anions were intercalated into the ZnAl-LDHs/AlO film by ion-exchange method. Thus colored coating films were fabricated on the substrates. Most of the LDHs plates of the film were grown with their ab face perpendicular to the substrates. The film became thicker than the film precursor due to the expanding of the interlayer space after the intercalation of dyes anions. The oxidative thermal decomposition temperatures of the acid yellow 49, acid yellow 25 and acid blue 25 were boosted by intercalating into the interlayer of LDHs due to the presence of host-guest interactions between the ZnAl-LDHs layers and guest dye anions. Thermal aging tests indicate that the thermal stability of the dye anions intercalated LDHs films are higher than those of the three dyes. The dye anions intercalated LDHs films possess better light fastness than the corresponding three dyes as indicated by photoaging tests.
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