We have plastic ice cube trays and I've noticed that when I refill them immediately after emptying them (while the tray is still very cold), the cubes that form stick to the plastic and are very hard to remove, cracking and breaking in the process, whereas if I rinse out the tray and let it warm to room temperature, then refill it and freeze it, the resulting cubes come out cleanly and easily.
Anyone know why this is? Is there some kind of bonding effect between water and cold plastic?