Self-sealing of mechanical damage in a fully cured structural composite

• Published in: Composites science and technology Vol. 79; pp. 15 - 20
• Main Authors: Moll, Jericho L., Jin, Henghua, Mangun, Chris L., White, Scott R., Sottos, Nancy R.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 18-04-2013; Elsevier
• Subjects: Applied sciences; Autonomic; Crosslinking; Damage; Exact sciences and technology; Fiber reinforced plastics; Forms of application and semi-finished materials; Healing; Laminates; Mechanical properties; Microcapsules; Microcrack; Polymer industry, paints, wood; Pressure cells; Self-healing; Solvents; Technology of polymers; Transition temperature; Woven composite; Microcapsules; Self-healing; Microcrack; Woven composite; Autonomic; Laminate; Fiber reinforced material; Epoxy resin; Mineral fiber; Composite material; Size effect; Crosslinked polymer; Glass fiber fabric; Cicatrization; Damaging; Dimethylsiloxane polymer; Microcapsule; Mechanical properties; Shear strength; Crosslinking; Experimental study; Glass transition temperature; Aminoplast; Thermal properties; Woven material
• ISSN: 0266-3538; 1879-1050
• DOI: 10.1016/j.compscitech.2013.02.006

A two part healing chemistry, stable to 150°C, is incorporated in a woven glass/epoxy fiber-reinforced composite with a glass transition temperature (Tg) of 127°C. The healing system is comprised of one type of microcapsules containing silanol end-functionalized polydimethylsiloxane, and a crosslinking agent, polydiethoxysilane, and a second type containing dibutyltin dilaurate catalyst in the solvent hexylacetate. The effects of microcapsule size and concentration on self-healing and mechanical properties including short beam strength, storage modulus and Tg were investigated. Self-healing of mechanical damage is assessed through the use of a pressure cell apparatus to detect nitrogen flow through a damaged composite. Complete self-healing was achieved when 42μm diameter microcapsules at a loading of 9 vol.% or 25μm microcapsules at a loading of 11 vol.% were added to the matrix.