The Material Origin of the Slow Rebounding Sponge

Slow rebound, also known as memory foam, is a kind of polyurethane polymer with open-cell structure. This material has special viscoelastic properties, reflecting soft material characteristics, and has strong impact energy absorption capacity.The molecules of this material are sensitive to temperature, so it is also called temperature sensitive memory foam.

The birth of memory foam can be traced back to a study by NASA in 1962: the design of life-saving system for Apollo command module. This material was developed and used on the seats of spacecraft to absorb the huge impact on astronauts during rocket (spacecraft) take-off, spacecraft's return to the atmosphere, some accidents (such as falling), and improve seat protection and comfort for astronauts. Because memory foam was originally born in NASA, it is often called space memory foam, which means technology originated from the U.S. space agency. This technology was first mentioned in NASA's report "Human Survival in Aircraft Emergencies," written by Charles Yost, the inventor of memory foam, an engineer at NASA at the time. In the 2005 NASA Spinoff document "NASA Spinoff 2005", the origin of memory foam and the development and application of this technology in the following decades are described in detail.

The open-cell molecules of this material will "flow" when pressed by external force and shift to fit the contour of the contact surface of the presser, so that the pressure will be evenly distributed to the whole contact surface, and when the pressure is eliminated, it will slowly return to its original shape. Therefore, this material was originally called "Slow Spring Back Foam". NASA's Ames Research Center fully applies this material to its new aircraft seat design, like memory foam seat pillow, which cannot only provide good impact protection for passengers in case of accidents, but also improve the comfort experience of passengers during long-term flight.

Although this kind of material has exciting characteristics, its production process and technology is very difficult.As a result, the material failed to achieve industrial production for more than a decade. But the technology was developed by Dynamic Systems Inc. (founded in 1969 by Charles Yost, the memory foam inventor, to develop and market memory foam technology and products). With the continuous efforts of the company, SunMate and Pudgee have been widely used in civil field, such as medical treatment, medicine, arrow target, helmet inner cushion, racing car seat cushion and functional insole. Dynamic System is undoubtedly the most authoritative company in the development of memory foam technology. Because of its invention (the inventor of memory foam is the founder of the company), it has won the most authoritative honor of "Govemor's Cup" at that time.

In the early 1980s, NASA released this material technology to industry, encouraging powerful companies to develop the technology to further benefit mankind, a company called Fagerdala World Foam which is a Swedish company focusing on functional foam realized the great potential of this new foam material with unique pressure decomposition characteristics, and seized this opportunity to actively participate in the development and improvement of memory foam technology.

In the development of memory foam technology, many companies and even qualified individuals carry out research and practice on this technology in different directions, fields and degrees. It is only because of various reasons that it is not widely known to the public, but their contribution to the improvement and development of memory foam technology cannot be ignored.