Page 63 - Plastics News January 2023

TECHNOLOGY

Changing Shapes At The Push Of A Button

accident or old age. Because those adjustments can be made: the base
affected often cannot move or turn material – thermoplastic polymers in
over by themselves, they often end the case of mattresses and metallic
up with very painful bedsores. In the alloys for other applications, includ-
future, it should be possible to avoid ing shape memory alloys – and, more
bedsores with the help of materials specifically, the microstructure,” ex-
that can be programmed to entirely plains Dr. Heiko Andrä, spokesper-
adapt their form and mechanical son on the topic at the Fraunhofer
properties. For example, the body Institute for Industrial Mathematics
rogrammable materials are true support of mattresses made from ITWM, one of the Fraunhofer CPM
Pshapeshifters. They can change programmable materials can be ad- core institutes. “The microstructure
their characteristics in a controlled justed in any given area at the push of these metamaterials is made up
and reversible way with the push of a button. Furthermore, the sup- of unit cells that consist of structural
of a button, independently adapting port layer is formed in such a way elements such as small beams and
to fit new conditions. They can be that strong pressure on one point thin shells.” While the size of each
used, for example, to make comfy can be distributed across a wider unit cell and its structural elements
chairs or mattresses that prevent area. Areas of the bed where pres- in conventional cellular materials,
bedsores. To produce these, the sup- sure is placed are automatically made like foams, vary randomly, the cells
port is formed in such a way that the softer and more elastic. Caregivers in the programmable materials are
contact surface is large which, as a can also adjust the ergonomic ly- also variable – but can be precisely
result, lowers the pressure on parts ing position to best fit their patient. defined, i.e., programmed. This pro-
of the body. This type of program- gramming can be made, for example,
mable material is being developed Materials and Microstructuring in such a way that pressure on a par-
by researchers at the Fraunhofer Materials for applications requiring ticular position will result in specific
Cluster of Excellence Programmable specific changes to stiffness or shape changes at other regions of the mat-
Materials CPM, who plan to bring it are being developed by research- tress, i.e., increase the size of the
to the market with the help of in- ers from Fraunhofer CPM, which contact surface and provide optimal
dustry partners. One of their goals is formed of six core institutes with support to certain areas of the body.
is to reduce the use of resources. the aim of designing and producing
programmable materials. So, how
Many people across the world are can we program materials? “Essen-
bedridden – be it due to illness, an tially, there are two key areas where

January 2023 PLASTICS NEWS 63