While I'm not familiar with AIX, it seems to support rsync, https://www.ibm.com/developerworks/aix/library/au-rsyncfamily/index.html. So no need to re-invent the wheel, use
rsync with the -t option to preserve modified times. See the page https://linux.die.net/man/1/rsync
Note that I would avoid using the
-a archive option as that includes too many attributes that it copies for you. So you might use something like
rsync -rltvx /folder/file /newfolder
If you're thinking of using this as a backup solution, then you will want to consider what you want to happen with files that are deleted on the source side on purpose, vs ones that were deleted by accident. By default
rsync does not delete any files in either source or destination. You can instruct it to delete files in the destination that do not exist in the source, creating a mirror of the source. However if this is your only copy of your data, you won't be protected against accidental deletions. There is also the problem of if a source file becomes corrupt somehow this can mirror to the copy before you realise, and you're in trouble again.
While I've seen (but never used) some posts, such as this, on using rsync to create a system of hard links to make a deduplicated backup repository of multiple 'snapshots' of your data, I personally enjoy the benefits of a more feature rich backup solution such as Borg Backup