Self-Healing Polymer Composites for Structural Application

Self-healing materials are the next-generation materials for high-performance structures. To reduce the fatigue and subsequent probability of failure along with extended service life of polymer and polymer composites, the self-healing concept has great potential. Today, polymeric composites are structural matrix and prone to failure against cyclic mechanical and thermal loading. Significant degradation of polymeric structures at surficial sites can be measured by barely visible impact damage (BVID), but internal micro-cracks are not easily detectable. Various damage modes make major damage sites in composites and further lead to catastrophic failure of the structure. On-site repairing of microscopic or macroscopic damages in polymer composites is a value-added function that is offered by self-healing techniques. Different extrinsic methods including encapsulation, hollow fiber embedment, and vascular methods are preferred, and some intrinsic, dynamic bonding is created by reversible covalent networks and supramolecular interaction based on H-bonding, metal-ligand, and ionomers. This chapter is preferred on the new trends and challenges regarding the structural health monitoring of polymeric composites against external mechanical and environmental impacts and extended service life and performance by utilizing self-healing strategies

Bioinspired approaches for toughening of fibre reinforced polymer composites

In Nature, there are a large range of tough, strong, lightweight and multifunctional structures that can be an inspiration to better performingmaterials. Thiswork presents a review of structures found in Nature, frombiological ceramics and ceramics composites, biological polymers and polymers composites, biological cellular materials, biological elastomers to functional biological materials, and their main tougheningmechanisms, envisaging potential mimicking approaches that can be applied in advanced continuous fibre reinforced polymer (FRP) composite structures. For this, themost common engineering compositemanufacturing processes and current composite damage mitigation approaches are analysed. This aims at establishing the constraints of biomimetic approaches development as these bioinspired structures are to be manufactured by composite technologies. Combining both Nature approaches and engineering composites developments is a route for the design and manufacturing of high mechanical performance and multifunctional composite structures, therefore new bioinspired solutions are proposed.This research was funded by the project “IAMAT—Introduction of advanced materials technologies into new product development for the mobility industries”, with reference MITP-TB/PFM/0005/2013, under the MIT-Portugal program and in the scope of projects with references UIDB/05256/2020 and UIDP/05256/2020, exclusively financed by FCT - Fundação para a Ciência e Tecnologia