University of Malta

Auxetic Medical
UOM Main Page
  * Contact
  * About
  * Academic Staff
  * Support Staff
  * Students
  * Industry
  * Entrepreneurs
  * Investors
  * Events
  * Standard Forms
  * Learn about IP
  * Our Technology
    * Synchronization for HS Video
    * UWB Antenna
    * Brain Controlled Selection
    * Brushless Motor
    * Multi Material Micro Injection Moulding
    * Kaptan
    * Runtime Verification
    * Reconstituted Stone
    * Insulating Block
    * Offshore Wind Energy
    * RibBridge
    * Surgical Suction Device
    * Breast Cancer Detection
    * Co-Crystal Drugs
    * Molecular Probe
    * Medical English Book
    * Cardio Thoracic
    * Auxetics General
    * Auxetic Medical
    * Speech and Language Assessment Tool
  * Funding
  * KTO Staff Resources

Auxetic Materials and Conversion process
Project Number: KD04JNG, KD01JNG and KD02RGC 
The Invention 

Auxetics are materials and systems which exhibit the very unusual properties of becoming wider when stretched and narrower when squashed, that is, they have Negative Poisson's Ratio.

A team of University researchers have extensive expertise on materials possessing auxetic properties and how they can be used to develop and manufacture new or improved commercial structures and products. They have also developed a novel way of converting conventional foam to auxetic foam through the use of solvent instead of heat.

The Novelty

Apart from possessing a Negative Poisson's Ratio, auxetic materials display additional unique qualities such as increased shear stiffness, an increased plane strain fracture toughness and an increased indentation resistance. When an object hits an auxetic material and compresses it in one direction, the material contracts laterally. That is, material flows into the location of impact creating a denser material which is less resistant to impact. auxetichitupdated
 015-applic-doming-helmetsAuxetic materials are also known to have better shock and vibration absorption properties. They also have a natural tendency to form dome-shaped double-curved surfaces, unlike conventional materials which tend to form saddle-shaped surfaces. Such materials are particularly desirable in applications that require highly curved hard surfaces, such as certain contours along the human body.

Applications or Industries

Auxetic materials, structures and foams can also be used to replace conventional components in various products used in specialised applications to produce higher quality products.

  • Hierarchical kink-less stents
  • Skin grafting
  • A bandage made from an auxetic microstructure impregnated with a healing drug.
  • Implants and dressings to adapt to body contours
  • Novel mattresses which reduce the incidence of bed sores


Development Status

Auxetic foam has been prototyped. 


Intellectual Property Status 

A patent application number GB1107220.4 was submitted by the University of Malta in the United Kingdom in May 2011. This was granted under number GB2480905 B in July 2013.  Patent application number MT4236 submitted in Malta was also granted to the University of Malta.

Back to the top


Project number: KD01RGX and KD02JNG 

The Invention

Cardiovascular disease is one of the leading causes of death in the Western world. An increasingly common form of treatment for this disease involves implanting a stent into an artery where a blockage is present. Each year, this type of treatment helps in saving the lives of many people who would otherwise suffer from heart attacks that result from blockages in blood vessels.


Stents used at present are sometimes inflexible and may not behave in the same way that a blood vessel inside the body would. This can result in stresses within the walls of the blood vessels, to which the body may react negatively. Additionally, when the stents are deployed, they tend to get shorter which may cause some difficulties in the correct placement of the stent within the vessel. 
Our team of researchers have designed heart stents using auxetic materials, making them less likely to collapse due to the material’s ability to expand the artery as the flow of blood increases. This capability keeps the artery open and reduces the occurrence of thrombosis, which is when the blood vessel becomes completely blocked leading to heart attacks.

The Novelty

Auxetic heart stents have an advantage over conventional stents by being able to widen the artery without shrinking in length hence risking becoming misplaced. Dislodging of heart stents is a major cause of their failure. Auxetic heart stents may overcome many dangers of conventional stents such as sliding out of place or damaging the artery. Stent insertion is, therefore, made easier for the doctor, giving a better result to the patient. Such interventions would be more efficient, reducing operating times and costs while sparing the patients from undue stress.

The stent was created for implantation into an artery.  However, by altering the size of the stent, one could envision the use of such a device for other scenarios (such as oesophageal cancer).
Development Status
The technology is in the initial design stage.
Intellectual Property Status
Intellectual Property protection measures are in progress.

 Back to the top

Commercial Interest

The team have extensive know how in the field of auxetics and how it can be applied to the development and manufacture new or improved commercial structures and products. We are interested in collaborating to design smart materials around their technologies.

Lead Originators and Relevant Publications


K Boba K., Bianchi M., McCombe G., Gatt R., Griffin AC., Richardson RM., Scarpa F., Hamerton I., Grima JN. (2016). 'Blocked shape memory effect in negative Poisson’s ratio polymer metamaterials.' ACS Applied Materials & Interfaces 8 (31), 20319-20328, 

Attard D., Degabriele EP., Grima JN. (2016). 'Nano networks exhibiting negative linear compressibility.' Physica Status Solidi (b) Vol 253, Issue 7 (1419-1427)

Attard D., Caruana-Gauci R., Gatt R., Grima JN. (2016). 'Negative linear compressibility from rotating rigid units.' Physica Status Solidi (b) Vol. 253, Issue 7 (1410 - 1418)

Evans E.E., Grima JN.(2006) 'Auxetic behavior from rotating triangles'. Journal of Materials Science 41; 3193–3196

Grima JN., Mizzi L., Poźniak AA., Wojciechowski KW. (2016). 'Planar auxeticity from elliptic inclusions.' Elsevier: Composites Part B- Engineering. 

Dudek KK., Attard D., Caruana-Gauci R., Grima JN,. Wojciechowski KW. (2016) 'Unimode metamaterials exhibiting negative linear compressibility and negative thermal expansion.' IOP Publishing: Smart Materials and Structures Vol 25, Issue 2 (0205009)

Azzopardi KM., Gatt R., Grima JN, Mizzi L.(2016). 'Auxetic perforated mechanical metamaterials with randomly oriented cuts.' Advanced Materials Vol 28, Issue 2 (385-389)

Attard D., Gatt R., Grima JN., Mizzi L, Pozniak AA., Wojciechowski KW (2015). 'Influence of translational disorder on the mechanical properties of hexachiral honeycomb systems.' Elsevier: Composites Part B: Engineering Vol 80 (84-91)

Agius TP., Attard L., Azzopardi KM., Casha A., Chockalingam N., Formosa C., Gatt A., Gatt R., Grima JN., Schembri-Wismayer P., Vella Wood M, Zarb F. (2015). 'Negative Poisson’s ratios in tendons: an unexpected mechanical response.' Elsevier: Acta biomaterialia Vol 24 (201-208)

Caruana-Gauci R., Dudek KK., Dudek MR., Grima JN., Wojciechowski KW. (2015) 'Colossal magnetocaloric effect in magneto-auxetic systems'.  IOP Publishing: Smart Materials and Structures Vol 24, Issue 8 (085027)

Attard D., Bajada M., Dudek KK., Gatt R., Grima JN., Scerri S. (2015). 'Maximizing negative thermal expansion via rigid unit modes: a geometry-based approach'. The Royal Society: Proc. R. Soc. A Vol 471 Issue 2179 (20150188).

Alderson A., Grima JN., Scarpa F., Wojciechowski KW. (2015). 'Auxetics and other systems of “negative” characteristics'. Physica Status Solidi (b) Vol 252, Issue 7 (1421-1425)

Gatt R., Grima JN., Mizzi L. (2015). 'Non‐porous grooved single‐material auxetics'. Physica Status Solidi (b) Volume 252, Issue 7 (1559-1564)

Cauchi R., Formosa JP., Grima JN. (2015). 'Carbon allotropes exhibiting negative linear compressibility'. Physica Status Solidi (b) Vol 252 Issue 7 (1656-1663) 

Attard D., Azzopardi KM, Gatt R., Grima JN., Mizzi L. (2015). 'Auxetic metamaterials exhibiting giant negative Poisson's ratios'. Physica Status Solidi (RRL)-Rapid Research Letters Vol 9 Issue 7 (425-430) 

Attard D., Azzopardi JI., Azzopardi KM., Briffa J., Casha A., Gatt R., Mizzi L., Grima JN. (2015). 'Hierarchical Auxetic Mechanical Metamaterials'. Nature Publishing Group: Scientific reports Vol 5 (8395)

Attard D., Cauchi R., Grech MC., Gatt R., Grima JN., Mizzi L., Rybicki J., Winczewski SN., Wojciechowski KW. (2015). 'Tailoring graphene to achieve negative poisson's ratio properties'. Advanced Materials Vol 27 Issue 8 (1455-1459)

Azzopardi KM., Brincat JP., Gatt R., Grima JN., Mizzi L. (2015). 'On the Effect of the Mode of Connection between the Node and the Ligaments in Anti‐Tetrachiral Systems'. Advanced Engineering Materials Vol 17 Issue 2 (189-198)

Gatt R., Grima R., Mizzi L., Trapani L. (2015). 'Mechanical Properties of 2D Flexyne and Reflexyne Polyphenylacetylene Networks: A Comparative Computer Studies with Various Force-Fields'. TASK Quarterly: scientific bulletin of Academic Computer Centre in Gdansk Vol 19 Issue 3 (237-296) 

Azzopardi KM., Brincat JP., Gatt R., Grima JN. (2015). 'Anomalous elastic properties in stishovite'. RSC Advances Vol 5 Issue 12 (8974-8980)

THINK Magazine 'Let The Blood Flow


Download summary - Auxetic Materials in healthcare [PDF]

Download summary - Stents [PDF


Industry Placements
Check out
Student with a Business Plan?

‘ERASMUS FOR YOUNG ENTREPRENEURS’ is the programme for you!

Last Updated: 11 July 2017

Log In back to UoM Homepage