# Smart Textiles: A Review and Bibliometric Mapping
## 3 Results and Discussion
### Clusters of KW as indicators of research areas  
**Cluster 1** (Red) was formed around the keyword **SMART****TEXTLES** (occurrence 1021), with 294 links and a total link strength of 842, which is the highest among all the authors' keywords. Overall, this leading term is closely linked to core terms in four other clusters. The red cluster is rather general and thematically covers smart textile materials, technologies, applications, and properties. Examples of keywords with high occurrence (>10) in this cluster are textiles, carbon nanotubes (CNTs), MXenes, strain sensors, supercapacitors, conductive textiles, conductive polymers, polyaniline (PANI), polypyrroles, reduced graphene oxides, graphene fibres, nanocomposites, nanoparticles, nanomaterials, nanotechnologies, energy storage, Joule heating, silver nanowires, silver nanoparticles, EMI shielding, shape memory, stretchable electronics, accelerometers, microcapsules, liquid-crystals, hydrogels, sol-gel, flexibility, flexible devices, and washable. The content analysis shows that among the materials, those that ensure the conductivity of the textiles through the use of nano-sized particles or through the use of nanotechnologies predominate. The applications are very broad and range from sensors (heart rate, pH, gas, monitoring human movements) to energy storage devices, EMI shielding, and flexible displays. The properties depend on the type of smart textiles and their capability; flexibility and washability are often emphasised. Some properties in this cluster are related to functional textiles rather than smart textiles, such as flame retardant, UV protection, self-cleaning, antibacterial, and antimicrobial. The reason may be historical, due to confusing terminology and incomplete standards for defining basic terms, namely smart  
Figure 11: Network of authors’ keywords in the field of smart textiles. and functional textiles, in the early stages of research and development of new materials and technologies in this field. **Cluster 2** (Green) is focussed on the keyword E-TEXTILES (occurrence 665), with 237 links and a total link strength of 573. The cluster presents smart electronic textiles, their constitutive parts, such as sensors and conductive yarns, their design, and their placement in computer networks for specific applications. Examples of specific keywords with high occurrence (>10) in this cluster include wearable electronics, textile electronics, wearable computers, sensors, wearable sensors, wearable computing, ubiquitous computing, physical computing, internet of things (IoT), body area network, body sensor networks, machine learning, artificial intelligence, deep learning, conductive yarns, conductive threads, textile transmission lines, wireless power transfer, textronics, health-care, telemedicine, e-health, activity recognition, capacitive sensing, radio frequency identification (RFID), prototyping, fashion, technology acceptance, washability, durability, and sustainability. This cluster is more structurally distinct and narrow. Keyword analysis identifies materials for the production of e-textiles, such as conductive fibres, conductive yarns, conductive threads, conductive materials, and CNT fibres. They are applied in textile body sensors, wearable sensors, sensor networks, wireless sensor networks, thermistors, and RFID. During the operation of an e-textile, data are collected from sensors that monitor various body parameters and transmitted to body area networks and the IoT using microprocessors, physical computing interactive systems, displays, and other user interfaces. Large amounts of data are processed using machine learning, deep learning, and other artificial intelligence methods. The emergence of e-textiles in the market is already impacting Industry 4.0, as well as e-health and telemedicine, by solving complex medical challenges and improving healthcare.