R help - May 2013 - Isolate polygons unionSpatialPolygons / single polygon instead of multipart polygon

Hi all, i used the function unionSpatialPolygons to dissolve polygons
according to an ID value. However, the results were not that i was
expecting. It created a SpatialPolygon and it grouped the objects according
to the ID value. i.e. one polygon had about 3 subpolygons with the same
value. How is the best way to create a new  SpatialPolygons with all
subpolygon as polygon and preserve their ID,

I share a screen shot where i selected one object and then i show the other
objects with the same ID value,

Also, i found a forum topic which has a similar issue,

http://r-sig-geo.2731867.n2.nabble.com/unionSpatialPolygons-single-polygon-instead-of-multipart-polygon-tc2765492.html#a2765496

Thanks,

-- 
*Alejandro Coca Castro***** ****
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