Why has Black Teen slang and the Hip Hop culture had such a powerful immersion into mainstream language?

Why has Black Teen slang and the Hip Hop culture had such a powerful immersion into mainstream language?

Paper instructions:
This is to be a college level thesis for graduation in the Communications discipline. It must be a scholarly paper discussing the Communications field & sub-disciplines. I'm interested in an Intrepretive/Qualitative research methodology. Must contain quotes and works from highly acclaimed Communications researchers, ie. Eble, Smitherman