Thin ceramic coatings for plastic containers to block moisture and oxygen

Overview

This technology applies very thin, well-adhered ceramic coatings to PET plastic bottles to dramatically reduce moisture and oxygen penetration. The approach adapts proven barrier coating methods originally developed for PET-based flexible electronics to rigid plastic packaging, addressing one of the packaging industry's most persistent challenges: extending shelf life and product integrity without adding bulky or hard-to-recycle material layers.

The coatings are produced through low-temperature, solution-based processing, which keeps manufacturing costs low and compatible with standard plastic container production lines. By offering both standalone ceramic films and ceramic-organic bilayer or multilayer structures, the technology can be tailored to specific packaging requirements while still supporting end-of-life recycling of the PET substrate.

Technical specifications

Coating approach:

• Organosilicon polymers such as poly(dimethylsiloxane) (PDMS) or poly(2-bromoethylsilsesquioxane) (PBESQ) are deposited onto PET via spin coating or dip coating
• UV/Ozone exposure converts the polymer layer into a SiO2 ceramic film
• Film thickness can be precisely controlled during deposition

Coating architectures:

• Standalone thin SiO2 layer for simple barrier applications
• Ceramic-organic bilayer that can be repeated to build multilayer structures for enhanced barrier performance
• Organic interlayers can act as sacrificial layers to enable clean removal of SiO2 prior to PET recycling
• SiO2 can be selectively dissolved in HF acid while PET remains intact, supporting material recovery

Validation methods used in prior development:

• Water vapor transmission rate measurements using the MOCON test
• Structural and chemical characterization via SEM, XRD, and FTIR
• Adhesion testing through tape-peeling, bending, and fragmentation tests

Technology readiness level

The underlying coating chemistry and processing routes have been demonstrated on PET substrates in prior work for flexible electronics applications, where moisture barrier performance and coating adhesion were verified through MOCON testing and multiple characterization techniques. The current proposal extends this validated platform to plastic container geometries, with planned deposition via spin coating or dip coating and SiO2 conversion through UV/Ozone exposure. The work remains at an applied research stage, with next steps focused on demonstrating barrier performance on bottle surfaces and validating multilayer architectures for packaging-relevant conditions.