A built-in sensor with carbon nanotubes coated by Ag clusters for deformation monitoring of glass fibre/epoxy composites

A multiwalled carbon nanotube network embedded in a polyurethane membrane was integrated into a glass fibre reinforced epoxy composite by means of vacuum infusion to become a part of the composite and has been serving for a strain self-sensing functionality. Besides the pristine nanotubes also nanotubes with Ag nanoparticles attached to their surfaces were used to increase strain sensing. Moreover, the design of the carbon nanotube/polyurethane sensor allowed formation of network micro-sized cracks which increased its reversible electrical resistance resulted in an enhancement of strain sensing. The resistance sensitivity, quantified by a gauge factor, increased more than hundredfold in case of a pre-strained sensor with Ag decorated nanotubes in comparison with the sensor with pristine nanotubes. © Published under licence by IOP Publishing Ltd.AV0Z20600510; LO1504, NPU, Northwestern Polytechnical University; STINT, Swedish Foundation for International Cooperation in Research and Higher Education; IGA/CPS/2017/002, FEDER, European Regional Development Fund; CZ.1.05/2.1.00/19.0409, FEDER, European Regional Development Fund; BelSU, Belgorod National Research University; -7AMB16AT033, MEYS, Ministry of Education, Youth and Science; Research and Development; FEDER, European Regional Development FundMinistry of Education, Youth and Sports of the Czech Republic, under the project Czech-Austrian mobility (program KONTAKT II) [7AMB16AT033]; OeAD; Austrian Agency for International Mobility and Cooperation in Education Research; Thomas Bata University in Zlin; Ministry of Education, Youth and Sports of the Czech Republic - Program NPU I [LO1504]; Operational Program Research and Development for Innovations - European Regional Development Fund (ERDF); Czech Republic [CZ.1.05/2.1.00/19.0409]; TBU in Zlin from the resources of the Specific University Research [IGA/CPS/2017/002]; Institute of Hydrodynamics [AV0Z20600510