# University of Waterloo makes cellulose paper coating to replace polyethylene in cups

- Published: 2026-11-13 15:05 UTC
- Section: Machines & Making › Materials science
- Tags: cellulose coating, plastic-free paper cup, polyethylene replacement, cellulose nanocrystals, cellulose acetate, microplastics, University of Waterloo, sustainable packaging
- URL: https://realtech.media/news/rt-9ba10b898fc0d879d70c1fc3_university_of_waterloo/

**Waterloo researchers made a cellulose coating for paper that resisted boiling water, oils and solvents in lab tests. It is a research-stage result; food-safety checks are still needed.**

![University of Waterloo makes cellulose paper coating to replace polyethylene in cups](https://realtech.media/media/2026/11/3721546ba2b2771d.webp)
*sciencealert.com*

Researchers at the University of Waterloo in Canada have developed a plant-based coating for paper that could replace polyethylene (PE) linings in beverage cups, according to sciencealert.com. The results were published in the journal ACS Sustainable Chemistry & Engineering. The authors describe this as a research-stage result. [1]

PE linings keep cups dry and sturdy, but they make recycling harder and fragment into microplastics over time. The study's senior author, materials chemist Shirley Tang, said some plastic liners shed particles very easily, especially at drink temperatures approaching 60 °C. [1] Under the same abrasion tests used to look for microplastic shedding, the new coating remained largely intact. [1]

## Cellulose composition and barrier properties

The coating consists of two components. Cellulose acetate forms the bulk of the material, and cellulose nanocrystals (CNC) add strength. [1] Both form hydrogen bonds with the paper itself, so no chemical adhesives are needed. [1]

These bonds create a tight network that fills the pores of the paper and forms a barrier against water, grease and gas. [1] In tensile tests, coated paper reached its best balance of rigidity and flexibility when CNC made up 3 percent of the coating's weight. [1] Compared with uncoated paper, the coating reduced oxygen transmission by more than tenfold. [1]

## Tests and remaining steps

In a five-day immersion test, the coating performed well against several solvents, including dichloromethane, sodium hydroxide and hydrochloric acid. [1] Tang said the coating also withstood boiling water and food oils. [1]

The team developed and tested the coating on thin brown paper towels, which normally absorb water quickly. After coating, they became water-repellent. [1] First author Sayan Ganguly said the coating allowed much thinner paper to be used while keeping the durability needed for beverage containers, which could reduce the amount of material and the cost. [1]

The researchers note that food-safety tests and regulatory evaluations must be completed before this coating, or similar ones, can be approved for commercial use. Tang said the timing of commercialization is uncertain. [1]

## Sources

1. [sciencealert.com](https://www.sciencealert.com/scientists-developed-a-plant-based-alternative-to-the-plastic-inside-your-coffee-cup)
2. [ua.news](https://ua.news/en/dovkolo-svitu/u-kanadi-rozrobili-pokrittia-shcho-mozhe-zaminiti-plastik-u-stakanchikakh-sciencealert)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-9ba10b898fc0d879d70c1fc3_university_of_waterloo/