Abstract:

Graphene has many excellent physical and chemical properties， and it is an ideal nanofiller for the preparation of composite materials. However， graphene is easy to agglomerate and difficult to be dispersed， making it difficult to uniformly hybrid with other matrix materials. In order to solve this problem， a new dispersant with high reactivity using 1，5-diaminonaphthalene and 3-glycidylpropoxytrimethoxysilane as raw materials was prepared. When the mass ratio of dispersant to graphene is 1∶1， the maximum mass concentration of graphene in water can reach 15 mg/mL， and it can exist stably at room temperature for more than 6 months. The dispersant molecule contains multi silanol groups， which are highly reactive and can self-cross-link to form uniform graphene coating. The obtained graphene dispersion was further blended with polyvinyl alcohol （PVA） to obtain a PVA-graphene composite film （PVA-GR）. Compared with blank PVA film， its mechanical properties are significantly improved. When the graphene mass fraction is 2%， the elastic modulus of the composite film increases by up to 52.8%. The prepared composite film is expected to be used in the field of high-performance composite materials.

Key words: Graphene, Dispersant, Self-cross-linking, Polyvinyl alcohol, Composites