Canada have never missed the title game since the women's tournament joined the Olympic programme and they kept that streak alive as Poulin made history, breaking the women's all-time scoring record with her 19th and 20th goals at the Games.
The defending champions will look to pick up a sixth gold against a talented young US team in the final on Thursday.
Forward Rahel Enzler put one on the board for the Swiss early in the third period but they could not match Canada’s firepower, as they were outshot 46-8.
Switzerland will play Sweden for the bronze on Thursday.
Canada’s “Captain Clutch” Poulin missed the final two group games with a knee injury but it scarcely looked like it as she plotted her path to the Olympic record after a scoreless first period at Santagiulia arena.
She clinched her 19th career goal at the Games with a nifty slap shot that hopped off the ice and over Swiss Andrea Braendli's pad to open the scoring as she surpassed compatriot Hayley Wickenheiser's previous goal-scoring mark, sending the maple leaf flags fluttering around the stands.
She added another less than seven minutes later, pushing the puck in as she dived forward in a chaotic scene at the crease.
Poulin bodied Swiss forward Laura Zimmermann into the boards four minutes later but avoided a major penalty call that would have derailed her dream evening, spending two minutes in the sin bin for the move.
Switzerland had surprised Nordic titans Finland in the quarter-finals but could not keep up the momentum on Monday, as Enzler's shot off an assist from Alina Muller early in the third period offered nothing more than a fleeting ray of hope.