Add 4D Properties from Pre-Shrinking to Create New Products
4D materials (designed to change form when activated by an external trigger) have been around for a long time. Example: Garment shrink proofing. In this case, a material is mechanically compacted the amount it is expected to shrink during a wash/dry cycle. When washed the pre-shrinkage is released, resulting in a garment that is temporally too big. After being tumble dried, the material shrinks back to its desired shape.
Now it is possible to give the property of pre-shrinking to nonwovens and composites as well, creating a whole new range of new products.
If the amount of compaction is increased — the material will grow when activated.
- A bandage that grows when wet to put more pressure on the wound.
- Packaging that signals when moisture has been present.
- A sheet that grows when heated as the softening point of the thermoplastic fiber is exceeded.
For more background on this development see our blog post.