Multi-Entry with 6-month Validity.

Does the "-Multi-Entry with 6-month Validity-" provide 180 days to Mainland China ? - What would be the requirements to get it? Im chilean citizen looking for visit Mainland for Multi-Entry because I would like to visit 2 universities (Jiangsu University & Ningbo University), so if there is any document I need to get at home and bring it back I don't have to request a new one and pay the fee.