Ill start with calculating a few of them, if anyone wants to add to the list go ahead. This isn't a list of what kind of CC's are actually viable in being able to chain so easily, but simply a list of who could keep someone CC'ed for the longest if they aren't interrupted. Please also let me know if the classes i have listed have issues. Not counting disarms due to all classes being able to still do SOME stuff while disarmed. Same with roots. Its normally the healer CC'ed so this is more spellcaster centered.
Rogue - 14 seconds of sap, 4.5 second silence garrote, 6 second Kidney, 8 second blind, 14 seconds sap, 4.5 seconds garrote, 6 second kidney, 4 second gouge - 61 seconds (55 seconds melee replacing garrotes with cheap shots, also could be longer with Combat revealing strike Kidneys, with 12 second disarms)
Balance Druids - 10.5 cyclone, 5 second mighty bash, 2 second pounce (displacer beast for stealth), 10 second silence solar+roots, 10.5 second cyclone - 38 seconds (17.5 seconds melee, though they have roots which could bridge the gap (with an extra 2 seconds), as well as add 14 seconds to the start, so with roots 33.5 seconds)
Other druids 17.5 seconds for all, no solar
Frost Mages - 14 seconds of poly/ring of frost, 5 second deepfreeze, 4 second silence - 23 seconds (19 seconds melee, with frost roots)
Fire mostly the same, but with 3 second combustion stun instead.
Paladins - 8 second repentance, 6 second stun, 6 second blind, 4 second repentence - 24 seconds
Warrior - 4.5 second gag order silence, 3 second charge stun, 4 second shockwave stun, 8 second fear, 3 second gag order silence - 22.5 seconds (15 seconds melee)
WW Monk - 5 second Leg sweep, 3 second FoF stun (2 seconds, but then procs again after for another 1 second in the same cast), 8 second paralyze, 4 second silence - 20 seconds (16 seconds melee) Iffy because FoF leaves small gaps
Other monks the same but remove 3 second FoF stun (brewmaster disorient could add 4 seconds)
BM Hunters - 12 second scatter trap, 3 second silence shot, 3 second intimidation, 4 second trap, 2 second scatter, 1.5 second intimidation, 1.5 second silence - 27 seconds (22.5 seconds melee, with possible 8 second root from disengage) + pet cooldown
Other hunters just remove 3 second intimidation