Dynamic inflatable structures may complement rigid structures in their long-term mission or permanent life in space. Multifunctional inflatable structures may serve as replaceable co-journeyers, temporal extensions, flexible arms and “sense organs” of rigid structures. Mass-energy effective and sensitive phase transitions are particularly feasible as a physical base for many functions of ultra-light inflatable structures. In this course, the article suggests a dual conceptual patent review: for space inflatable structures and for functionally employed phase transitions patented in the field of space technology or potentially applicable for it. On a quality level, smart inflatable structures with intrinsic phase-transitional properties are considered as well. The method of durable protection extending the life and functions of inflatable structures is also reviewed.