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Compact structureSurface energy* < 41 dynes/cmContact angle ≈ 70 oC Very less functional groups which can
interact with dyesSmooth fibre surfaceLeads to Less hydrophilicity High dyeing difficulty*Surface energy is defined as the interaction between the forces of cohesion and the forces of adhesion which determines whether or not wetting occurs on spreading a liquid over a surface.
Surface activation
Surface etching
Functional group generation
Surface polymerization
AirOxygenNitrogenPeroxideSteam, etc.Combination of gases
In situ polymerizationPost polymerization
Polymerization done usingAcrylic acidAcrylamideAcrylonitrileMethyl methacrylate, etc.
WettabilityX-ray Photoelectron SpectroscopyAtomic Force MicroscopyScanning electron microscopyDyeability (K/S value)
Exposure time (s)
Surface energy
increased to about
73 dynes/cm
1 5
20
80
Pressure (kPa)0.5 9
20
80
Gas flow rate
Dyeability behavior is claimed to be as same as wettabilityIntroduction of COOH functional groupGraft polymerization of monomers like acrylic acidCationic dyeableSurface etching enhances the shade depth
Exposure time
