Damage healing in fiber reinforced thermoset polymer composites has been generally divided into intrinsic healing by the polymer itself and extrinsic healing by incorporation of external healing agent. In this study, we propose to use a hybrid extrinsic-intrinsic self-healing strategy to heal delamination in laminated composite induced by low velocity impact. Especially, we propose to use an intrinsic self-healing thermoset vitrimer as an external healing agent, to heal delamination in laminated thermoset polymer composites. To this purpose, we designed and synthesized a new vitrimer, machined it into powders, and strategically sprayed a layer of vitrimer powders at the interface between the laminas during manufacturing. Also, a thermoset shape memory polymer with fire-proof property was used as the matrix. As a result, incorporation of about 3% by volume of vitrimer powders made the laminate exhibit multifunctionalities such as repeated delamination healing, excellent shape memory effect, improved toughness and impact tolerance, and decent fire-proof properties. In particular, the novel vitrimer powder imparted the laminate with first cycle and second cycle delamination healing efficiencies of 98.06% and 85.93%, respectively. The laminate also exhibited high recovery stress of 65.6 MPa. This multifunctional composite laminate has a great potential in various engineering applications, for example, actuators, robotics, deployable structures, and smart fire-proof structures.
Laminated multifunctional composites are highly desired in modern lightweight engineering structures. The purpose of this study is to develop a composite laminate with impact tolerance, delamination healing, strain sensing, Joule heating, deicing, and room temperature shape restoration functionalities. In this study, a novel self-healable and recyclable shape memory vitrimer was used as the matrix, unidirectional glass fabric was used as reinforcement, and tension programmed shape memory alloy (SMA) wires were used as z-pins. To provide multifunctionality, the programmed SMA wires were further twisted and formed into sinusoidal shape. Copper wire strands were hooked to the sinusoidal SMA z-pins to make them a closed circuit. Low velocity impact, compression after impact, damage self-healing, deicing, and room temperature shape restoration tests were conducted. The tests result show that the desired multifunctionality of the laminated composite was achieved. The hybrid laminate provides a promising design for lightweight load-carrying engineering structures.
more » « less- Award ID(s):
- 1946231
- NSF-PAR ID:
- 10367585
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Journal of Composite Materials
- Volume:
- 56
- Issue:
- 14
- ISSN:
- 0021-9983
- Page Range / eLocation ID:
- p. 2267-2278
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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