Eco-Friendly, Sustainable, Lightweight, Porous Cellulose Sponge for Crop Growth

This technology uses ‘cellulose sponges’ that can be used to grow pick-and-eat crops without soil. The inventors have tested diverse cellulose derivatives and have determined the best performers. Hydroxyethyl methylcellulose was shown in testing to have a higher water-retention property, higher durability, low density and malleability, and equal performance when compared to current rockwool systems. The crosslinked nature of the technology overcomes the common drawback of current sponges’ material releasing lots of dust and loose fiber that can be dangerous to humans in closed environments. The technology does not threaten respiratory systems while maintaining lower density and high water-retention properties. The other challenge is needed soil to grow crops with the sponges. To overcome this challenge and simplify the cellulose-based plant growth system, the technology controlled the component-structure-property-processing of cellulose materials for plant growth without soil. Furthermore, by testing diverse cellulose derivatives, the inventors identified the best performers to grow pick-and-eat crops, such as lettuce.

Background:
Cellulose is the most abundant natural biopolymer with a global reserve of up to 75 billion tons from a variety of sustainable sources such as wood, plants, and algae. Due to the good safety profile of these biopolymers to humans and the environment, cellulose and its derivatives are widely used as a binder, thickener, emulsifier, and dispersing agent in various applications such as food, cosmetic and personal care, pharmaceutics, construction, and agriculture. Food-grade cellulose derivatives were crosslinked with food-grade citric acid to construct hydrogels with high water-retention properties. This cellulose hydrogel was buried under the soil and successfully grew a plant with the benefit of providing water and nutrients longer than just soil itself. Although direct plant growth on cellulose materials without soil would be more convenient, the small pores in the cellulose hydrogel prevent the roots from penetrating through and thus, a plant supporting system, such as soil, is required. 

Applications: 

• Hydroponics
• Grow crops in various environments

Advantages: 

• Can grow crops without soil
• Eco-friendly
• Lower density
• High water-retention properties
• Sustainable
• Food safe
• High porosity
• Durable
• High malleability