Mendeley TY _ JOUR ID - 1403092548875 TI - A review on the self-healing polyurethanes based on dynamic physical and chemical bonds JO - Iran Polymer Technology, Research and Development JA - ES LA - fa SN - 2538-3345 AU - Heydari Mahmoud AD - دانشگاه جامع امام حسین ع Y1 - 2025 PY - 2025 VL - 3 IS - SP - 59 EP - 72 KW - Polyurethane KW - self-healing KW - dynamic covalent bonding KW - shape memory KW - soft and hard phase DO - N2 -

Self-healing mechanisms in polyurethanes, including the use of dynamic covalent bonds such as disulfide, imine, boroxine, alkoxyamine bonds, etc., and dynamic non-covalent bonds such as single and multiple hydrogen bonds, metal coordination,  etc., were investigated and reviewed. The conditions for healing and the external driving factors required to initiate self-healing of these mechanisms were investigated. The results showed that in many mechanisms such as the use of dynamic boroxine or imine bonds, the use of an external driving factor such as surface condensation with ethanol solution or the application of high temperatures is necessary and unavoidable. A review of scientific literature showed that the use of polyols with switching capabilities in the soft phase will benefit from the shape memory capability and further facilitate self-healing, and will eliminate the need for external force and pressure to contact and bring cracked surfaces closer. The results showed that the combination of dynamic covalent and dynamic non-covalent mechanisms is a key to achieving desirable mechanical properties and facilitated self-healing conditions. The principles governing the selection of each of the soft and hard segments to maximize self-healing properties under ambient conditions were reviewed. The results showed that hard phases with minimal interaction from curing agents or asymmetric chain extenders such as isophorone diisocyanate or isophorone diamine will facilitate self-healing. The use of polyols such as polytetramethylene ether glycol containing oxygen atoms will contribute to the soft phase in self-healing by the hydrogen bonding mechanism.

UR - rimag.ir/en/Article/48875 L1 - rimag.ir/en/Article/Download/48875 ER -