TREATMENT OF REINFORCEMENTS

Presented by Sumi M Nair

COMPOSITE

A composite material can be defined as a combination of two or more materials that results in better properties than those of the individual components used alone.

REINFORCEMENT• Discontinues phase in a

composite• Strong and stiff

Physical Treatments• Plasma treatment• It is a surface modification

technique.• Improve the compatibility

between a reinforcement and matrix.

• Create a variety of desirable surface functionalities.

Chemical treatment of Reinforcements

• Chemical treatment utilizes the chemical agents to modify the reinforcements

• Improve adhesion between reinforcement and matrix

• Improves reinforcement strength• Improves moisture resistance and mechanical

properties of composites

Alkali treatment(Mercerization)• Increases surface roughness • Increases mechanical interlocking • Removes surface impurities • Decreases crystallinitySilane treatment• Improves interfacial strength• Increase thermal stablity• Increase tensile strenth.Acetylation• Reduce hygroscopic nature• Improve dimensional stability• Improves adhesion• Improves thermal stability

.

Benzoylation• Reduces hydrophilic nature of reinforcement• Improves adhesion• Improves thermal stabilityAcrylation and Acrylonitrile grafting• Decreases water absorption• Increases tensile strength and young's

modulusMaleated coupling agents• Widely used to strengthen composite• Used in Poly propylene matrix• Better wettability• Improves flexural strength and hardness• Reduced water absorption

Reaction mechanism if silane treatment

Reaction mechanism of maleated coupling agent

Permanganate treatment• Highly reactive Mn3+ions are

is responsible for initiating graft polymerization.

• Improved fiber/matrix interaction and compatibility

• Improved mechanical properties

Peroxide treatment• Free radicals react with surface

groups of the matrix.• Increase in surface roughness• created good interlocking.