Environmentally Friendly Latex Substitute for Weather Balloons
The required material must
1) be nontoxic, environmentally friendly, wildlife safe, and dissolve or quickly degrade to harmless components within hours or days of being introduced into the environment (e.g., when exposed to moisture);
2) have mechanical properties (very low weight, moderate tensile strength, non-stickiness, relative impermeability to gases, moderate resistance to puncture or tearing, sealability) compatible with the production of single-use lighter-than-air gas-filled balloons ranging in diameter from 0.5 meter to 2 meters or more, latex-like elasticity is preferred but not mandatory ;
3) be opaque or colorizable for visibility;
4) be available or easily producible at low cost (< $1 per sq. ft.).