Preparation of self-healing additives for concrete via miniemulsion polymerization

formulation and production challenges

Shima Taheri*, Simon Clark

*Corresponding author for this work

Research output: Contribution to journalArticle

Abstract

Concrete structures undergo internal damage; this usually starts at the atomic level with defects that then grow and form cracks, which can propagate through the material. Here, a method of preparation of poly(methyl methacrylate) (PMMA) nanocapsules adhesive system via miniemulsion polymerization technique is reported, where MMA + DMA (resin + accelerator) and BPO (hardener) components are separately encapsulated by PMMA shells. The crack-healing potential of these nanocapsules was then investigated by embedding them into the mortar matrix. The prepared PMMA core–shell self-healing nanostructures survived the mixing and hardening processes, and the hardened mortar alkaline environment. The stress fields associated with propagating cracks (load‐induced cracking) broke the brittle/weak inert shell of these core–shell structures, resulted in releasing the healing agents to bridge the nascent and early-stage fractures (< 10 µm) in a short time. Long-term healing was achieved through the formation of polymorph calcite crystals in the presence of moisture and CO2, which improved the durability of mortar by filling the gaps. Formulation design (addition of chemical admixtures) and process parameters (blade design and mixing speed) were found to directly impact the uniform distribution of nanocapsules, the survival rate of nanocapsules, and the overall strength of the hardened concrete. The stepwise approach to formulate and fabricate a novel high-strength self-healing concrete system unlocks unique opportunities to design nanomaterials that safeguard the integrity of concrete structures.
Original languageEnglish
Article number8
Pages (from-to)1-15
Number of pages15
JournalInternational Journal of Concrete Structures and Materials
Volume15
Issue number8
DOIs
Publication statusPublished - 25 Jan 2021

Bibliographical note

Copyright the Author(s) 2021. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.

Keywords

  • self-healing concrete
  • miniemulsion polymerization
  • PMMA nanocapsules
  • concrete crack
  • crack healing

Fingerprint Dive into the research topics of 'Preparation of self-healing additives for concrete via miniemulsion polymerization: formulation and production challenges'. Together they form a unique fingerprint.

Cite this