Abstract
Polymers used in structural applications often suffer from microcracks that
propagate and lead to unexpected failures. Inspired by the ability of
biological systems to autonomously repair themselves, self-healing
polymers are being developed with the aim to decrease costly, time
consuming maintenance and increase the durability and reliability. The
overall objective is the development of an autonomous self-healing polymer
that uses a vascular network to carry the healing agents to the damaged
site. In my master thesis the focus was on the selection of a two-part amine-epoxy
healing chemistry. The vascular system is prepared by embedding
electrospun sacrificial submicron fibres into an epoxy matrix. After curing
the fibres are dissolved leaving a network of submicron channels behind in
which the healing agenst are infused by capillary forces.
Low viscosity amines and epoxies have been selected and combined into
amine/epoxy healing systems with glass transition temperatures at full cure
below, around and above room temperature to determine the influence of
the glass transition temperature on the healing efficiency. From the curing
kinetics and the interdiffusion it was seen that the studied systems were
sufficiently slow at room temperature to allow for interdiffusion of amine
and epoxy over up to 1 mm before the diffusion is blocked by the formed
network. Swelling tests revealed that most of the selected healing agents
diffuse into the polymer and swell it. This might be beneficial for crack
closure and improved adhesion between the healing system and the epoxy
matrix.
Epoxy samples healed by manually applying the healing system with the
highest glass transition temperature have shown healing efficiencies larger
than 90% after curing 7 days at room temperature. The three point bending
tests have demonstrated that the higher the glass transition temperature of
the healing system is, the higher the healing efficiency is.
propagate and lead to unexpected failures. Inspired by the ability of
biological systems to autonomously repair themselves, self-healing
polymers are being developed with the aim to decrease costly, time
consuming maintenance and increase the durability and reliability. The
overall objective is the development of an autonomous self-healing polymer
that uses a vascular network to carry the healing agents to the damaged
site. In my master thesis the focus was on the selection of a two-part amine-epoxy
healing chemistry. The vascular system is prepared by embedding
electrospun sacrificial submicron fibres into an epoxy matrix. After curing
the fibres are dissolved leaving a network of submicron channels behind in
which the healing agenst are infused by capillary forces.
Low viscosity amines and epoxies have been selected and combined into
amine/epoxy healing systems with glass transition temperatures at full cure
below, around and above room temperature to determine the influence of
the glass transition temperature on the healing efficiency. From the curing
kinetics and the interdiffusion it was seen that the studied systems were
sufficiently slow at room temperature to allow for interdiffusion of amine
and epoxy over up to 1 mm before the diffusion is blocked by the formed
network. Swelling tests revealed that most of the selected healing agents
diffuse into the polymer and swell it. This might be beneficial for crack
closure and improved adhesion between the healing system and the epoxy
matrix.
Epoxy samples healed by manually applying the healing system with the
highest glass transition temperature have shown healing efficiencies larger
than 90% after curing 7 days at room temperature. The three point bending
tests have demonstrated that the higher the glass transition temperature of
the healing system is, the higher the healing efficiency is.
| Original language | English |
|---|---|
| Publication status | Published - 17 Mar 2016 |
| Event | 13th Chemistry Conference for Young Sientists, Chemcys 2016 - Blankenberge, Belgium Duration: 16 Mar 2016 → 18 Mar 2016 |
Conference
| Conference | 13th Chemistry Conference for Young Sientists, Chemcys 2016 |
|---|---|
| Country/Territory | Belgium |
| City | Blankenberge |
| Period | 16/03/16 → 18/03/16 |