PolyHIPE contains interconnections between pore, caused by the high packing density
and material shrinkage upon curing. These pores can range from the nanometers to
It is possible to form spherical microsphere of polyHIPE by forming a double emulsion (an emulsion of an emulsion) which leaves droplets of polyHIPE within a water phase. At our lab we specialise in photocurable materials and are able to photocure the polyHIPE droplets instantly with UV radiation.
PolyHIPE is a material state rather than a specific material. A polymer high internal phase emulsion is a simple emulsion which contains pores taking up greater than 76% of the materials volume. This separates it from a MIPE (medium internal phase emulsion) which contains porosity below 76%. As the porosity is higher than the normal stacking density of spheres within an object the resulting material contains interconnected pores.
The above images are thinly sectioned particles formed from polyHIPE material. It can be observed that pores are present throughout the material. Interconnected pores are also vi sable although its important to remember that the pores are usually 3D and would contain interconnections around their circumference not just the ones visible in this 2D plane.
Microsphere material & particles