Balloons (the physical object) in designs?

Hi guys,

I'm really new to using SolidWorks, having just made the migration across from another software package, so I'm very sorry if I posted this in the wrong section or if it's a stupid question.

Anyway, many of our designs involve the use of one or more large weather balloons with differing thickness, diameter, and filled with different gases. Is there any way to model this into my design (in 2d and/or 3d), and if so, how? If not, does anyone know of anything that would let me do this?

Thanks a lot.

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