Modelling the post treatment process of model implants prepared by in situ polymerized poly(ε-caprolactone) using a BF3–glycerol catalyst system

The post treatment process of a poly(ε-caprolactone) (PCL) model implant prepared using a boron trifluoride (BF3) catalyst and glycerol initiator by in situ polymerisation process for craniofacial and maxillofacial treatment is modelled using a ‘moving-boundary’ diffusion model. A numerical method was used to solve a system of diffusion equations of the model. The variable diffusion coefficient (D) was correlated with crystallinity (xc) of the polymer which is a function of its molecular weight (Mw) and its degradation rate constant (kd), D=f(xc(Mw,kd)). The post treatment time and the molecular weight retained after post treatment can be obtained using this model. The modelling results show that the process is potentially suitable for manufacturing thin model implants of complex shape.