HS-PS2-6: Molecular Level Structure of Designed Materials

HS-PS2-6:  Communicate scientific and technical information about why the molecular-level structure is important in the functioning of designed materials.

 PS2-6 Evidence Statements

I introduced this topic to students by showing them a short video about gecko adhesive (synthetic setae).  Geckos feet are super-sticky due to numerous Van der Waals forces that form between the tiny endings of hairs that are found under their feet and whatever surface they are climbing on.  After the video we discussed the importance of molecular level interactions for the designed materials shown in the video.  Video options include the Weird Connections Episode "How Sticky is Your Gecko?", the segment about gecko adhesive from Nova's "Making Stuff Smarter" or "Bio-Inspiration:Nature as Muse" from KQED-Quest.


By Bjørn Christian Tørrissen - Own work by uploader, http://bjornfree.com/galleries.html, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=6874833

Brainstorm list of materials students could research to meet this standard.

  1. Polylactic acid (PLA)
  2. Beta blockers
  3. Graphene
  4. Polyethylene terephthalate PET)
  5. Proton pump inhibitors (PPI's)
  6. Angiotensin cutting enzyme (ACE) inhibitors
  7. Ranitidine - Zantac
  8. Nylon
  9. Polytetrafluoroethylene (teflon)
  10. Polyvinyl chloride (PVC)
  11. Polypropylene (PP)
  12. Low-density polyethylene (LDPE)
  13. High-density polyethylene (HDPE)
  14. Vantablack




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