Trifluoroacetic acid has a pKa of 0.2 and a BP of 72°C. It can be purchased and handled as a neat liquid. (be careful with it though, because it is quite corrosive and has a high vapor pressure--a few drops of neat TFA will burn skin instantaneously, and I imagine a breath of the vapors would not be very pleasant!) Depending on what else is in your reaction mixture, you might be able to rotovap it off and reuse it...

Polyacetyls are not stable if the initiator and capping agent are removed. You can use a different initiator and capping agent but they have to remain in the product.

Notice an object made from polyacatyls is unstable when scratched or subjected to hot water. The molecules when broken somewhere in the middle completely decompose one link at a time until the chain fragments are completely gone. 

Manufacturers like polyacetyls because of low cost, but mostly because they don't have to clean the molds very often. Residues get damaged and just decompose, often removed as vapor.

Maybe you have an excess agent, the excess might be removed carefully without damage to the product. Usually there is no excess because the amount used governs the average molecular weight of the polymer..

Tabet

You may use boron trifluoride dibutyl etherate and rotovap or Amberlite IR-120 cation-exchange resin in its acid form and filter off (heterogenous catalyst).

Good Luck