Tremco Acoustical Sealant - Tremco Commercial Sealants & Waterproofing
There are other acoustical caulks but Tremco is a pretty popular and time tested one. I like to use it for all work with poly and any indoor caulking where there will be no painting or touching. You actually might be able to paint it. Not sure as I never use it for those purposes. I think its intended purpose was to seal corner seams in drywall when there is resilient channel behind the rock so the wall can actually move a little bit.