News from Nanotechjapan


Drastic Improvement in Adhesion Property of Polytetrafluoroethylene (PTFE) via Heat-Assisted Plasma Treatment Using a Heater

 Osaka University announced on 25 August 2017 that researchers from the university and  Hyogo Prefectural Institute of Technology have drastically improved adhesion property of PTFE via heat-assisted plasma treatment using a halogen heater. The results were published online in Scientific Reports*.

 Although PTFE has excellent property for extended applications, for instance, coating of cooking pans to avoid oil stains, adhesion to a foreign substance has been very difficult. Surface treatment of PTFE by high power plasma (for example, High-P: 21.7 W/cm2) has been a possible way to overcome the difficulty, however, energy cost and limitation of adhesive area were still challenging. 

 In this study, researchers -treated a PTFE sheet by plasma at atmospheric pressure while heating surface upto 260℃ by a halogen heater. Plasma power was 8.3 W/cm2 (Low-P), and the surface temperature was 95℃ in case of no heating. Surface temperature under High-P plasma was raised to 260℃. Adhesion strength with isobutylene-isoprene rubber (IIR) was measured via the T-peel test. The adhesion strengths of Low-P without heating was 0.17 N/mm, Low-P with the heater was 2.2 N/mm and High-P without heater was 2.3 N/mm. Surface analysis results of the PTFE samples showed that heating during the plasma treatment promotes the etching of the weak boundary layer (WBL) of PTFE, resulting in a sharp increase in the adhesion properties of PTFE.  

*Yuji Ohkubo, Kento Ishihara, Masafumi Shibahara, Asahiro Nagatani, Koji Honda, Katsuyoshi Endo & Kazuya Yamamura, "Drastic Improvement in adhesion property of polytetrafluoroethylene (PTFE) via heat-assisted plasma treatment using a heater", Scientific Reports. Vol.7, Article number: 9476 (2017), doi: 10.1038/s41598-017-09901-y; Published online: 25 August 2017