I am a PhD student in materials engineering. What is D3O? It is not a chemical, but rather a "polyurethane energy-absorbing material" (from Wikipedia). I would wish to know and study the chemical composition of this impact shock absorbing materials.


3 Answers 3


The inventor, Richard M. Palmer, has filed at number of patents on "energy absorbing materials", one of which is US patent (7,381,460).

On the other hand, there does not seem to be any peer-reviewed publication by Mr Palmer.

There's always the option to ask the manufacturer D30 for further information and/or material samples.

The possible downside of such a cooperation is that you might not be allowed to report on the progress of your experimental work on conferences or in publications due to an NDA previously signed!

  • $\begingroup$ The patent says the dilatant material they use is made by Dow Corning. They refer specifically to "Dow Coming under catalogue no. 3179". 3179 Datasheet. The datasheet says primary it is for toys, presumably like Silly Putty, which according to the Silly Putty Wiki, is also a silicone-based polymer. $\endgroup$
    – DanG
    Dec 29, 2023 at 19:35
  • $\begingroup$ The patent also has a specific example of the chemistry (see Example 1 therein). Note that the patent recently expired. $\endgroup$
    – DanG
    Dec 29, 2023 at 20:18

D3O is basically polyurethane with polyborodimethylsiloxane, or at least that is what the patent what's you to believe.

Polyborodimethylsiloxane is an expensive chemical and the thickness of the D3O back protector and limb products is on average the same with the thickness of their competitors using "normal" polyurethane.


Regarding "Polyborodimethylsiloxane is an expensive chemical and the thickness of the D3O back protector and limb products is on average the same with the thickness of their competitors using "normal" polyurethane."

Please note that: 1. PBDMS is much different from 'normal' foams such as PU, PS, TPU, EVA, etc. 2. PBDMS is a viscoelastic liquid or non-Newtonian fluid having high Deborah numbers 3. There are covalent bonds within the polymer, but hydrogen bonds between the molecules. It provides ‘Grab-release’ mechanism with dynamic, reversible network(Si-O-B)

  1. PBDMS is an interfacial nano-adhesive, hydrogen-bonded, self-healing, hydrophobic, super stretchy or flubber-esque, etc. Again, it forms dynamic, reversible network.

In conclusion, PBDMS is a spider silklike siloxane. The emulsified gels or suspensions with nanoparticles(ex. carbon nanotube, graphene, cellulose nanofibrils, nanoclay, etc.) may find many potential applications. Its features are:

① spider silk-like, ② energy absorbing ③ self-healing ④ can be stretched several times its length before it breaks ⑤ stronger than carbon steel ⑥ tougher than carbon fiber and Kevlar ⑦ antimicrobial, fragrant ⑧ waterproofing, nonflammable


  1. https://pubs.acs.org/cen/whatstuff/stuff/7848scit3.html
  2. https://www.facebook.com/Aussie-Aerogels-552921575091430/?ref=bookmarks
  3. https://omnexus.specialchem.com/tech-library/article/2018-wmf-startup-challenge-innovative-ideas (#4, K-armourgel and Spider Silk Sand by Korea Aerogels)
  • 1
    $\begingroup$ If you are associated with the company, that is no problem. But you should disclose it (informally, like a line saying "Note I am working for Company Abc"). A nice answer! $\endgroup$ Aug 22, 2018 at 11:47

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