5 Types of Flexible Composites Transforming Your Healthcare

Simply put, a composite is a material made from two or more materials that have different properties. When combined together, the chemical and physical properties of the different materials work together to form a unique material or composite. Combining materials is nothing new. The Egyptians were doing it millenniums ago, combining mud and straw to make buildings, boats, and pottery. The 20th century saw great leaps in composites, largely spurred on by the second world war. In recent decades, however, composite materials have aided the production of a new gold standard in healthcare.  

Leaps in Wound Care

Composites can take advantage of the most attractive characteristics of materials, combining them in a way to meet the desired specifications. Wound care is one key area that reaps the rewards of this process. Usually comprised of three or more layers, composite wound dressings have the advantage of addressing multiple needs in one single dressing. The bottom layer is usually a semi- or non-adherent material, preventing the dressing from sticking to the wound while allowing moisture to get through to the next layer. The middle layer is an absorptive material, pulling moisture away to prevent bacterial growth and promote healing. The function of the outer layer is to protect the wound from infection and allow air to circulate. Consider some components of composite bandages and how they contribute to healing.

• Foam dressings made of hydrophilic polyurethane can absorb up to 15 times its weight in fluids, making it a perfect middle layer for wounds with a lot of exudate. 
• Films are made of thin sheets of polyurethane coated with an adhesive, forming a very thin "second skin." They are ideal for wounds with little or no exudate, especially those in awkward locations, such as the elbow or knee.  
• Hydrocolloids are often part of the middle layer in a dressing. They contain gel-forming substances, such as sodium carboxymethyl cellulose and gelatin, and excel at maintaining moisture balance. 
• Hydrogels are made of gels that can absorb and retain large amounts of liquid, maintaining the right amount of moisture to promote healing. They are soft, flexible, and provide a cooling sensation that often brings pain relief to the wearer. 
• Electrospun nanofibers is an emerging technique that yields continuous fibers with diameters down to the nanometer scale. Researchers call this process the "next-generation polymer composites."  One example is the use of silver's antibacterial properties in wound care dressings. Silver has long been known to be effective in preventing infection. However,  it also inhibits healing when applied directly to wounds. The use of polymeric nanofilms containing silver nanofibers is changing the way the silver is applied. Specifically, it releases silver at a rate 100 times lower than conventional dressings over a 10-day period. The composite dressing also contains a dissolvable microfilm that also helps to prevent the negative effects on wound healing from the silver. 

Composites of the Future

E-skin devices are the subject of much chatter in the medical and technology arenas. Skin-like composites have long been used for attaching medical devices, such as IVs, catheters, and heart monitors. Soft silicone elastomers, such as polydimethylsiloxane and silicone rubbers are stretchable and function fairly seamlessly against the skin. Scientists are working on ways to combine technology into these composites for wearables and devices of the future. Electronic sensors with sensing capabilities that detect approaching objects, measure temperature and applied pressure already exist. Imagine wearable technology integrated into a comfortable composite skin that could detect harmful movements when you are playing your favorite sport, sending an alert before an injury occurs. 

Composites are not just providing a means to hold the technology, however. Advanced Science News explains, "One way of achieving this aim in polymer composites is through the introduction of electrically conductive carbon nanostructures into a non-conductive polymer. Upon inclusion of enough carbon nanostructures, the polymer composite becomes electrically conductive—a phenomenon known as electrical percolation. Upon percolation, changes in strain, humidity, temperature, and other external excitations yield changes in the electrical conductivity of the nanocomposite, and their correlation can be used to develop self-sensing smart materials." 

Conclusion

Composites are revolutionizing healthcare, from simple wound care to intricate burn healing to innovative sensing technology.