The Influence of Halloysite Nanotube Addition on Some Properties of Room Temperature Vulcanized Maxillofacial Silicone before and after Simulated Aging Al-Obaidi Khalid A.1,*, Ali Mohammed Moudhaffer M1 1Dept. of Prosthodontics, College of Dentistry, University of Baghdad, Baghdad, Iraq *Corresponding Author: Khalid A. Al-Obaidi, Dept. of Prosthodontics, College of Dentistry, University of Baghdad, Baghdad, Iraq, Email: abdalbasit@codental.uobaghda.edu.iq
Online published on 23 December, 2019. Abstract Although silicone is the most commonly used material in face and neck prostheses, but there are some drawbacks concerning its mechanical performance and durability. Therefore, this study was carried out to investigate the impact of halloysite nanotube (HNTs) on selected properties of VST-50F silicone before and after simulated weathering. A pilot study was conducted to determine the most suitable weight percentage of HNTs to be incorporated into VST-50F silicone. Accordingly, 1% and 1.5% weight percentage were chosen to be the experimental groups and compared with control. The main study involved the preparation of 240 samples divided equally into two groups;group 1 (before weathering) and group 2 (after weathering). Group 2 samples were subjected to simulated aging for 200 hour. After that, all sample wre subjected to five mechanical tests, namely tear strength, tensile strength, elongation percentage, surface roughness and hardness. The research readings were collected and statistically analyzed using ANOVA, post-hoc and paired t-test tests. Additional tests were also performed including Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) that test revealed a well dispersion fashion of HNTs within VST-50F silicone, while FTIR didn't exhibit any chemical reaction between the silicone and HNTs. However, mechanical tests results before aging showed significant rise in all tests readings except for roughness, where the change was non-significant. Meanwhile, the study results after weathering revealed a significant decline in tear strength, tensile strength and elongation percentages, yet roughness didn't change significantly, but hardness increased remarkably. Reinforcing VST-50F with HNTs improved some of its mechanical properties but didn't protect it from aging consequences. Top Keywords Maxillofacial silicone, halloysite nanotube, fillers, simulated weathering. Top |