Study On Surface Polumerization Modification Of Layered Double Hydroxides

As a kind of inorganic functional materials,when LDHs are added as functional additives to organic polymers,their compatibility with the polymers has a certain impact on the dispersion of LDHs in polymers.At present,organic compounds such as coupling agents are used to modify the surface,which can’t improve the compatibility well between LDHs and polymers,leading to limited material application.By introducing polymers on the surface of LDHs,the surface tension of LDHs can be effectively reduced,and its dispersion in polymer base materials can be improved.In this work,the "grafting to" method was used.First of all,introducing small molecules with unsaturated double bonds on the surface of LDHs,the styrene in solution self-polymerization and copolymerization with unsaturated double bonds and terminated at the surface of LDHs.As a result,PS@LDHs was produced.The amount of PS grafted on the surface of LDHs gradually increased with the increase of the amount of PVP added.With the increase of AIBN,the amount of PS increased first and then decreased.With the increase of the amount of styrene,the amount of PS increased first and then decreased.The obtained PS@LDHs was added to xylene,and its dispersion stability was significantly improved.In this dissertation,the "grafting from" method was used.Firstly,an amino group and an unsaturated double bond were introduced on the surface of LDHs.The redox reaction between the surface amino group and Ce4+ resulted in the generation of active radical sites,which in turn triggered the polymerization of acrylic monomers.It was terminated by copolymerization with unsaturated double bonds on the LDHs.PAA@LDHs was produced.The amount of PAA grafted on the surface of LDHs decreased with the ratio of the two silane coupling agents changed,and then increased gradually with the increase of the amount of ceric ammonium nitrate,and gradually increased with the increase of the amount of acrylic acid added.The obtained PAA@LDHs was added to 100 parts of PE and PVC in one part,and the dispersion in PE and PVC was significantly improved by fluorescence microscopy.In this paper,the rich hydroxyl groups on the surface of LDHs were used to introduce reactive groups,which led to the surface polymerization reaction.The surface of LDHs was modified by graft polymerization,the compatibility between LDHs and polymers was improved,and the dispersion of LDHs in polymer materials was improved.