An Aqueous Photocrosslinkable Chitosan-PVA (Polyvinyl Alcohol) Binder for Tapecasting Alumina Substrates

An aqueous photocrosslinkable binder system for tapecasting ceramic substrates was investigated based on chitosan (CS) and polyvinyl alcohol (PVA) by adding UV photoinitiator 2-hydroxy-1- [4-(hydroxyethoxy)phenyl]-2-methyl-1-propanone (Darocur 2959). Alumina green sheets were prepared by using the binder and exposed to UV irradiation. SEM, FT-IR, XRD and DSC verified that these CS/PVA polymeric films or green sheets obtained using the binder were homogeneous, which indicated that CS was compatible with PVA in the binder, polymeric films and green sheets. Blending CS and PVA may created a semi-interpenetratin structure with good mechanical properties enough for handling and machining, and the process may not have oxygen retarding effect in arcylamide system.