is it good grammar to write

work satisfactory
or
satisfactory work

Both are okay but 'satisfactory work' is advised as that is the conventional usage: adjective (describer) followed by the noun (being described).

'Satisfactory work' is fine. That's because 'satisfactory' is an adjective premodifying the noun 'work'.
'Work satisfactory' isn't really acceptable. It depends on whether 'work' is a noun or a verb.
Example: 'The manager thought the account clerk's work satisfactory.' In this case work is a noun so satisfactory is post modifying it.
But:
'He completes his work satisfactory' is not grammatically acceptable since here 'work' is a verb and verbs are modified by adverbs not adjectives so you should use 'satisfactorily'.