You can chain Quick-Play Spell Cards from your hand as long as it is during your turn.
Example #1:
Player A activates "Dark Hole."
Player B chains "Imperial Order."
Player A chains "Mystical Space Typhoon" from his/her hand.
Also, you can chain or play a Quick-Play Spell Card from your hand during any Phase of your turn, even during your Battle Phase.
Activating/chaining/playing Quick-Play Spell Cards from your hand, during your turn, is not limited to Main Phase 1 or 2 and can occur in the Draw, Standby, Battle, and End Phases