# Why is TPEE called Monolithic?

> Source: https://breathablefilm.com/news/knowledge-center/why-is-tpee-called-monolithic-membrane/
> Author: kh_sales02
> Published: 2026-04-28
> Updated: 2026-08-28

## Key takeaways

- "Monolithic" refers to a solid-state structure — TPEE films like AquaVene™ contain absolutely no physical pores, unlike microporous films that rely on billions of microscopic holes.
- A monolithic membrane acts as a total barrier to liquids, viruses, and bacteria while still allowing moisture to pass through a chemical process rather than physical holes.
- TPEE moves moisture via hydrophilic molecular chains that act like a molecular conveyor belt, chemically grabbing water vapor molecules on one side and releasing them on the other.

## Frequently asked questions

### Why is TPEE called Monolithic?

TPEE (AquaVene) is called monolithic because it is a solid-state polymer layer with absolutely no physical pores, unlike microporous films that rely on billions of microscopic holes to pass vapor. Instead, it moves moisture through molecular diffusion: hydrophilic molecular chains act like a conveyor belt, chemically grabbing water vapor molecules on the inside, passing them through the solid polymer, and releasing them outside, which is why a monolithic membrane can be a total barrier to liquids, viruses, and bacteria while still being breathable.

### How can a membrane with no physical pores still be breathable?

A monolithic membrane like TPEE (AquaVene™) uses hydrophilic molecular chains that act like a molecular conveyor belt — chemically grabbing water vapor molecules on the inside, passing them through the solid polymer, and releasing them outside, without ever opening a physical hole for liquid, viruses, or bacteria to cross.