Would this be possible using a permalocked TID memory space?
No, it cannot. Permalock means that the memory block on the chip is permanently locked and that block of memory cannot be written to or changed. The tag ID (TID) is always permanently locked because this is the serial number that identifies the microchip in the RFID transponder and the manufacturer of the chip (the Electronic Product Code is the serial number that identifies the product the tag is on). Since the TID is always locked, you cannot write the temperature readings from a temperature sensor linked to the RFID transponder in that memory block. You would need to use one of the user memory blocks in the chip.
—Mark Roberti, Founder and Editor, RFID Journal