Simple B-tree question

Hi there! I have to write a very simple application that will insert batches of about to 50-100,000 records into a single (but much much larger) "master" table. This process will be executed every night until the end of time. The "master" table has only one unique index and I can not drop the index while processing the batches because we are running a 7-day 24-hour operation. This unique key grows as time goes by. The question is: Is there a "best order sequence" for the records in the batches to be inserted? Should I sort them? Should I randomize them? or It does not matter? Regards, Alex Barragan