Bio-based capillary foam technology for sustainable solid foam manufacturing

Overview

This technology leverages capillary foams, a class of ultra-stable, moldable foams formed by frothing particle suspensions containing a small percentage of water-immiscible oil. By selecting biodegradable particles and curable bio-derived oils, the resulting solid foam offers a cost-effective, environmentally friendly alternative to conventional foam materials. The approach enables manufacturers to produce foams with tailored mechanical strength, water resistance, and oil resistance, suitable for applications in packaging, insulation, and other industrial uses where sustainability and performance are priorities.

Technical specifications

Key features:

• Particle and oil selection: Compostable polymer particles combined with curable bio-oils form the basis of the foam structure
• Ultra-stable bubble formation: Particle-and-oil-covered bubbles are interconnected by a particle network held together by capillary forces from the immiscible oil
• Moldability and shaping: Curable oils allow the foam to be shaped into solid forms through extrusion or injection molding, with steam providing bubble formation
• Demonstrated versatility: Stable foam formation has been shown with particles including ethylcellulose, hypromellose, and protein, and oils including vegetable oils and acrylics
• Additive compatibility: Oil-soluble colorants and other additives can be incorporated into the foam
• Weight-bearing capability: Lab-scale molding has demonstrated shape retention and structural load capacity

Technology readiness level

The capillary foam concept has been validated across multiple particle-oil systems, with published and unpublished work demonstrating stable foam formation, shape retention in lab molding, weight-bearing capability, and additive incorporation. Future work will focus on identifying particle and oil combinations that deliver target properties including degradability, stiffness, strength, and liquid resistance, using a modeling approach to guide component selection. Optimization of foaming, curing, and drying processes will ensure compatibility with existing manufacturing infrastructure such as extrusion and molding systems. The technology is at an early-to-mid stage of development, ready for collaborative research to advance component optimization and process scale-up.