The Study Of Composite Pigments Based On Modified Sepiolite

Organic pigments,which itself have many excellent properties,such as high color fastness,gorgeous colors,and low toxicity,making its have a broader market demands,recently have slowly devoured the market shares of inorganic pigments,which widely used in printing ink,plastic,ceramic,coating.However,organic pigments have some disadvantages like poor dispersion,poor weatherability,poor resistance of acid and alkali,poor flow performance,which severely limit it its application in industry.Therefore,it is of great significance to further modify the organic pigments to improve its performance or to develop a new type of more stable organic pigment.At present,the synthesis of new superior pigment structure is still a very difficult and complicated process,and a simple and effective modification technology to improve the performance of the existing pigment is getting more widely attentions.In this paper,sepiolite is used as an inorganic core,and the inorganic/organic compound pigments with more stable performance are prepared by modifying the azo pigments with different modification methods.Using kernel method,we modified methylene blue azo dyes based on sepiolite as the inorganic,and successfully prepared more stable composite organic pigments.Firstly,sepiolite was modified by organic acid using one step hydrothermal method,and then the CA-Sep modified methylene blue via kernel method,and the inorganic/organic composite organic pigments were prepared successfully.Reactant concentration,temperature and reaction time are the key factors for preparing CA-Sep/MB compound pigments.The stability of CA-Sep/MB composite pigment can be further improved by the quality ratio of methylene blue and sepiolite as well as ball grinding,roasting temperature and pH of solution.Compared with the Sep/MB hybrid organic pigments,the stability of CA-Sep/MB organic pigments against alkali and acid,organic solvent,and thermal stability have obviously improved.The BET,ZETA,FTIR,XRD,SEM and TEM analysis characterizations show that the MB molecules were adsorbed onto the surface,the grooves,or the mouth of channel of sepiolite,and also proved that the structure of sepiolite were rearranged after modified by organic acid structure,enhancing the adsorption performance for organic pigments.Using kernel and cladding methods,we furthe modified methylene blue based on sepiolite and the surface of Nano-SiO2 was constructed and the hydrophobic groups with high surface energy were grafted in the manner of dehydration condensation to form the cladding layer,and successfully prepared Sep/MB@POS composite organic pigments.Contact angles and rolling angles of the prepared superhydrophobic composite pigment are 160° and 4° respectively under different solutions.CTEOS,CHDTMS,reaction temperature and reaction time are the important factors for preparing Sep/MB@POS superhydrophobic composite pigments.Compared with hydrophilic composite pigment,the modified Sep/MB@POS superhydrophobic composite pigments against alkali and acid,organic solvent,and thermal stability have obviously improved.And the TEM,SEM,FTIR,XRD,XPS analysis characterizations prove that the presence of the surface of alkyl bonds(CH2-)on the surface of Sep/MB@POS superhydrophobic composite pigments.