Sampler automation error

I'm working on a Substance Sampler automation script. It creates one material per texture file in the same folder of the project file, imports one texture per material using the AI-based Image to Material filter, adds some more layers and then proceeds with the next material.

The problem is that it keeps filling up the RAM of my computer, and once it is full, usually after a few dozen of materials, the AI algorithm keeps failing and then it only creates black materials. What can cause this, and how can I avoid it?