This is a chip bag.
Estimated persistence
≈ 80 years
Why it matters
Most chip bags are multilayer composites: different plastics bonded together, often with a thin metal layer. That structure keeps chips fresh, but it also means the bag cannot be recycled like a single-material package. Separating those layers is difficult and rarely done in municipal systems.
The result is predictable. Most chip bags become trash. They can persist for decades, and like other plastics they tend to fragment over time rather than cleanly decompose. The practical problem is not one heroic purchase, but the repeat pattern of buying the same hard-to-recover package over and over.
Details
Mechanism
Chip bags are layered from different plastics and usually a thin metalized barrier. That structure blocks air and moisture well, but it is hard to separate back into recyclable parts.
After disposal
Most chip bags are treated as trash in municipal systems. Over time they persist, tear, and fragment rather than cleanly decomposing.
Better substitutes
The main improvement is to reduce how often you buy the package at all. Treat it as an occasional purchase instead of a background default. Larger formats, bulk options, or a different snack can cut down the number of repeat single-use bags.