Fabrication of Functional Polymeric Nanofoams with An Bottom-up Strategy

The introduction of nanovoids to the polymeric material can finely tune the material properties like dielectric constant, refractive index, density, thermal conductivity, leading to many emerging functional materials like anti-reflective coatings, opaque polymers and super thermal insulation materials. Though polymeric foams have been widely used in industry, the preparation of polymeric nanofoam of high porosity presents a great challenge.

We will present a novel bottom-up strategy to construct polymeric nanofoams. Firstly, the non-collapsed hollow polymeric nanoparticles with shell thickness on the order of 10 nm were prepared by the interfacially confined reversible addition fragmentation transfer (RAFT) miniemulsion polymerization. The void fraction and average diameter of the hollow polymeric nanoparticles could be largely tuned up to 0.58 and from 68 nm to 180 nm, respectively. The non-collapsed hollow polymeric nanoparticles were then used to construct polymeric nanofoams, which hold promise in many application fields such as anti-reflection coatings, ultra-thermal insulation materials.