Preparation And Properties Of Intrinsic Self-Healing Natural Rubber

• المؤلف الرئيسي: Thajudin, Nuur Laila Najwa
• التنسيق: أطروحة
• اللغة: الإنجليزية
• منشور في: 2021
• الموضوعات: T Technology; TA401-492 Materials of engineering and construction. Mechanics of materials
• الوصول للمادة أونلاين: http://eprints.usm.my/56239/

Self-healing rubber is a new group of smart material which has the ability to restore the damages without manual intervention. The work carried out in this thesis explored the potential of intrinsic self-healing natural rubber based on reversible metal thiolate ionic networks, thermo-reversible Zn2+ salt bonding and thermo-reversible disulphide exchange. The metal thiolate was added in natural rubber (NR) compound through peroxide vulcanization system at different zinc thiolate content (0, 10, 20, 30, 40 phr). Evidence for reversible metal thiolate ionic networks was obtained through Fourier-transform infrared spectroscopy (FTIR) and swelling density analysis. The tensile properties and tear strength recovered at 90 %, and 132.6 %, respectively when the broken sample was brought into contact for 10 minutes at room temperature. The fatigue lifespan of the materials increased by 60 % compared with the non-self-healing sample. Thermo-reversible salt bonding approach is based on the ionic interactions between Zn2+ ions from zinc thiolate crosslinker and carboxyl groups which were introduced by grafting different content of methacrylic acid (MAA) (0.5, 0.7, 1.0, 1.5, 2.0 phr) onto NR chains. Evidence for Zn2+ salt bonding was obtained from FTIR analysis. The results revealed that the materials able to recover up to 76 % under tensile mode and 100 % under tear mode and fatigue test. For self-healing approach through thermo-reversible disulphide exchange, the NR chain was rafted with different Bisphenol A (BIS A) content (0, 2, 5, 7 phr). Evidence for disulphide networks was obtained from FTIR analysis. The results revealed that the materials able to recover up at 150 0C.