%0 journal article
%@ 0743-7463
%A Wischke, C., Lendlein, A.

%D 2014
%J Langmuir
%N 10
%P 2820-2827 
%R doi:10.1021/la4025926
%T Method for Preparation, Programming, and Characterization of Miniaturized Particulate Shape-Memory Polymer Matrices
%U https://doi.org/10.1021/la4025926
10 
%X Their capability to change their shape on demand has created significant interest for shape-memory polymers (SMPs) in minimally invasive surgery. To evaluate the miniaturization of SMP matrices for small-sized implants or controlled release systems, a strategy to prepare and evaluate microsized SMP model particles is required. This methodological study reports the emulsion-based preparation of ∼30 μm microparticles (MPs) from a phase-segregated SMP, poly(ε-caprolactone) [PCL] and poly(ω-pentadecalactone) [PPDL], with a particular focus on the effects of process parameters such as polymer solvents or stabilizer type/concentration on formation and size distribution of SMP MPs. Processes for the preparation of SMP MP-loaded water-soluble polymer films with tailored mechanical properties were developed and applied for programming the SMP MP to a temporary ellipsoid shape by film stretching. For the functional evaluation of shape recovery of MPs, a light microscopy-based setup with temperature control is proposed by which the stimuli-induced switching of the microsized SMP matrices could be confirmed. Overall, by applying this methodological strategy to various thermoplastic SMPs, a routine to identify and characterize the microscale functionality of SMPs in miniaturized applications will be broadly accessible.