In situ synthesis and preparation of TiO/polyimide composite containing phenolphthalein functional group.

In this paper, titanium dioxide (TiO)/phenolphthalein-type polyimide (PPPI) composite was synthesized in situ polymerization, the diamino phenolphthalein type compound and dimethylacetamide as the matrix, and TiO as the filler. The mechanical property and thermal conductivity properties were used to characterize the properties of the obtained composite. A diamine monomer containing more benzene rings of phenolphthalein and an ether bond in its main chain were prepared, synthesized by a nucleophilic substitution reaction and a hydrazine hydrate reduction reaction. Polyimide composite had the same structure as that of a diamine monomer. And it was synthesized by solution imidization and heat imidization. The results showed that TiO improved the dispersibility, alignment and interfacial strength of the TiO/PPPI composite. The mechanical property of polyimide composite was increased with the increasing TiO loading. And a suitable addition of TiO could enhance the mechanical properties of polyimide system. Compared to polyimide resin, the TiO/PPPI composite had a higher thermal conductivity with the increasing of TiO content. All of these changes in properties were closely correlated with the TiO/PPPI composite, which could form an interaction interface structure in the system. [ABSTRACT FROM AUTHOR]