Extrinsic healing

Key words self-healing, intrinsic healing, extrinsic healing, functionality,... 

The concept of self-healing was first clearly proven using extrinsic healing approaches to restore structural integrity (White et al, 2001) and thus it is in... 

In the simplest case of extrinsic semiconductors, the temperature and all chemical processes modifying the abundance and nature of the defect states will modify the zero of the binding-energy scale and so cause shifts that are solely due to cahbration and not at all to local electronic structure modification (e.g. most oxidation states in an oxide are not affected if a fraction of the extrinsic defects are created or healed by diffusion of oxygen species, yet shifts up to 2eV can result from this process). 

Fig. 11.13 Coagulation flow chart Blood coagulation events are divided into initiation, extrinsic and intrinsic path activation, and the common path to fibrin. Controls are fibrinolysis as healing begins and inhibition of clotting factors in a healthy (uninjured) blood vessel. Diseases are excessive bleeding (hemophilia) and excessive clotting (Original figure)...

Self-healing or restoration of lost functionalities without external help is a dream come true with self-healing polymers (Ai ssa et a/., 2012). Healing mechanisms can be extrinsic (the healing compound is isolated from the polymer matrix in capsules, fibers or nanocarriers) or intrinsic (the polymer chains temporarily increase mobility and flow to the damaged area) (Billiet et al, 2013) and are responsible for restoration of properties such as structural integrity (White et fll, 2001), surface aesthetics (Yao et a/., 2011), electrical conductivity (Tee et fl/., 2012), hydrophobicity and hydrophilicity (Ionov and Synytska, 2012), mechanical properties (Jones et al, 2013), etc. 

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