GOVAERT Filip Centexbel - Belgian Textile Research Centre

Carbon Nanotubes Based Textile Coatings Filled with Aluminium Flakes for High Reflectivity Heating and Lighting Applications

Co-authors VANNESTE Myriam

Textile coatings based on polyacrylates and polyurethanes filled with carbon nanotubes (CNT) for electrical conductivity were functionalised with aluminium flakes for higher light and heat reflectivity. Electrical conductive textile coatings are presented with up to 15 wt % of CNT, based on the solid weight of the binder. Coating formulations with variable CNT concentrations were applied on polyester and cotton woven and knitted fabrics by different textile coating techniques: direct coating, transfer coating and screen printing. The coatings showed increasing electrical conductivity with increasing CNT concentration. The coatings can be regarded to be electrical conductive (sheet resistivity <103Ohm/sq) starting at 3 wt% CNT. The degree of dispersion of the carbon nanotubes particles inside the coating was visualized by scanning electron microscopy. The CNT particles form honeycomb structured networks in the coatings, proving a high degree of dispersion. This honeycomb structure of CNT particles is forming a conductive network in the coating leading to low resistivity values. Additionally these CNT based coatings were functionalised with aluminium flakes for higher light and heat reflectivity. The compatibility of aluminium flakes in the binder material was investigated. Formulations with 1 wt% aluminium up to 15 wt% aluminium were prepared and applied. Reflectivity measurements prove the increasing light reflectivity with increasing aluminium content. Applications for this coating technology can be found in resistive heating textiles and base electrodes for flexible OLED lighting applications.