Your goal is honorable - but I'm not sure there is a decent algorythm out there as yet to dice up your model.
I have read many posts .. for example using Dark Physics and building tree's in "chunks" so they can "come apart" later when hit or something....
I think you will need to make diced up versions of your model yourself.
also I think trying to get code to do it for you would not be good in game - and if you can do it - I'd personally make a "utility" program to load the model - dice it into pieces, and save the pieces for loading and using in game.
There are resons for this - and one of them is you don't want your final game loading/creating deleting objects to much cause there is a bug lurking that will bite you during gameplay. Better to hide/exclude then delete - and Vertex manipulation OFTEN means needing to create a mesh from a source object, delete the source object, create a new object from the modified mesh etc... this is not a good thing... nor is tons of creation and deleting of any sort in game.
