Model PLA - Aluminum Interface

[JackDelasoudas]

Hello,

I want to model PLA and Aluminum interface. My main problem is with the boundary conditions. Do I have to model seperatelly the polymerisation of the PLA and then add it to a data file with Aluminum? How to I secure that it will not cross the boundary and that the density of the final structure is correct? Or do I have to model everything at once? Like create atoms of Al, Pack PLA on top and then somehow equilibrate the system to the correct density. My goal is to measuyre interface mechanical properties

Thank you in advance.