Natural rubber–based composites filled with bioglasses from a CaO‐SiO 2 ‐P 2 O 5 ‐Ag 2 O system. Effect of Ag 2 O concentration in the filler on composite properties

• Published in: Polymers for advanced technologies 2020-03, Vol.31 (3), p.574-588
• Main Authors: Al‐Sehemi, Abdullah G., Al‐Ghamdi, Ahmed A., Dishovsky, Nikolay T., Radev, Lachezar N., Mihailova, Irena K., Malinova, Petrunka A., Atanasov, Nikolay T., Atanasova, Gabriela L.
• Format: Article
• Language: English
• ISSN: 1042-7147; 1099-1581
• DOI: 10.1002/pat.4798

Bioactive glass was first synthesized by L. Hench in 1971. There are many studies on the properties of several metals and metal ions dopants used in the SiO 2 ‐CaO‐P 2 O 5 system of bioglasses, such as Ag, Cu, Zn, and Fe. A number of authors have carried out research related to the influence of silver oxide on the properties of bioglasses . However, publications on the properties of elastomer‐based composites containing bioactive glasses are relatively scarce. We have not found in the literature studies discussing how silver oxide concentration in bioglasses of the CaO‐SiO 2 ‐P 2 O 5 ‐Ag 2 O system affects the significant properties of a natural rubber biocomposite. In this regard, the purpose of the present work is to investigate the aforementioned influence on the properties of this type of composites, namely, vulcanization, physicomechanical, thermal, dynamic, dielectric, electric, and thermoconductive characteristics. We have established those parameters of the composites to be impacted considerably by both degree of filling with bioglass and the silver oxide content in the latter. The improvement in the composites thermostability and some of their physicomechanical performance is the most significant. The volume resistance decreases, and the thermal conductivity coefficients increase. Results from scanning electron microscopy and energy‐dispersive X‐ray (EDX) analyses have confirmed the influence of silver oxide initially on the phase composition of the bioglass, hence on the properties of the biocomposites through changes in the bioglass used as filler. The dielectric characteristics of some of the biocomposites suggest that they can be used as substrates and insulating layers in flexible antennas for short‐range wireless communications.