Abstract
A series of photoluminescent nanocomposite polyurethane adhesives were elaborated from a chemoenzymatic prepared diol of caprolactone (PCL-diol) and ethylene glycol with an excess of two different isocyanates: i) hexamethylene (HDI) and (ii) isophorone (IPDI)) diisocyanates. Adhesive formulations were filled with functionalized poly(amido-amine) (PAMAM) carbon nanotubes (f-MWNTs) and carbon quantum dots (CQDTs). Dry swine gut was used as substrate and mechanical tests were performed to explore the performance of the adhesives. The obtained materials were characterized by infrared spectroscopy (FT-IR), energy surface by contact angle, differential scanning calorimetry (DSC), hydrolytic degradation, and mechanical testing under tension, lap shear, T-peel, wound closure, and burst pressure. Among the main results were the formation of covalent bonds between the substrate and the adhesive, and the fact that the mechanical strength of the nanocomposite adhesives was superior to that of the unfilled adhesives. Compatibility of nanocomposites with the substrate was achieved by increasing wettability by the incorporation of both nanofillers. Also, adhesives filled with only CQDTs and with MWNTs-CDQTs combined showed photoluminescence activity under ultraviolet light.
Acknowledgments
The authors wish to thank C.J. Zepeda-Coronel and M.A.S. Romero-Pérez, students at Centro Universitario de Tonalá of the University of Guadalajara, for their fruitful assistance to carry out experimentation and measurements.
Data availability statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.