Ethanol‐induced crack healing in poly(methyl methacrylate)

Abstract

The crack healing induced by ethanol in poly(methyl methacrylate) (PMMA) has been studied at temperatures of 40–60°C. Crack healing occurs because the effective glass transition temperature of PMMA is reduced to below the test temperature by ethanol plasticization. It is found that crack closure rate is constant at a given temperature. The fracture strength of healed PMMA is lower than that of the original samples. By comparing the fracture stress with the morphology of the crack edge on the PMMA surface, we found that a high degree of swelling is responsible for the incomplete recovery of mechanical strength. The fractography of the completely healed sample shows a very different fracture morphology from that of virgin PMMA. The transport of ethanol in PMMA also is studied. At lower temperatures, transport is described by ideal Case II behavior. As the temperature increases, the kinetics shift from ideal Case II to anomalous behavior. The first stage of crack healing is controlled by Case I transport. © 1994 John Wiley & Sons, Inc.

RETRACTED: Controlled Light Cross-Linking Technique to Prepare Healable Materials

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Safe and cost-effective rapid-prototyping of multilayer PMMA microfluidic devices

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Solvent-Promoted Self-Healing Epoxy Materials

“…Solvents such as ethanol and methanol were used to seal the cracks of thermoplastic polymers (i.e., poly(methyl methacrylate)) when the polymer was heated. [9][10][11][12][13][14] This healing mechanism involves wetting of the polymer surface and swelling of the bulk polymer material, which leads to reptation and interlocking of the chains across the crack plane to recover virgin mechanical properties and heal a crack. More recent research has explored the effects of tetrahydrofuran (THF) in epoxy-amine polymerizations.…”