Frictional Property of Textile Fiber

When the textile materials are processed, then friction is developed between the fibers. The properties which are shown by a textile material during friction is known as frictional property. This properties are shown during processing. Too high friction and too low friction is not good for yarn. Therefore it is an important property when yarn manufacturing and processing.

Frictional properties depend on-

1. Composition of the material

2. State of the surface of the material

3. Pressure between the surfaces

4. Temperature

5. Relative humidity %

Co-efficient of friction:  

Frictional force is proportional to the normal or perpendicular of a material due to its own weight.That is, F ∞ N Or, F = μ N Or, μ = F/NWhere, F = Frictional force, N = Normal / perpendicular forceHere, μ is the proportional constant known as “co-efficient of friction”.So, co-efficient of friction can be defined as the ratio of frictional force and perpendicular force.

Methods of measuring co-efficient of friction:  

Capstan method is most commonly used to measure co-efficient of fraction. Capstan method can be classified into two classes-

1. Static capstan method

2. Dynamic capstan method

Other methods- 

1. Buckle & Pollitt’s method

2. Abboh & Grasberg method

3. Gutheric & Olivers method

Influences of friction on textile material:

Friction holds the fibers in a sliver and hence the sliver does not break due to its’ own weight. Friction helps in drafting and drawing.· Uniform tension can be maintained during winding & warping because of friction.· Friction helps to make yarn by twisting during spinning.· Friction increases lusture and smoothness of the yarn and the fabric.· Friction makes more clean material. 

Demerits of friction on textile material:· 

Friction causes nap formation.· High static friction causes high breakage of yarn during weaving.· If the frictional force is high, the handle properties of fabric will be low.· Friction generates temperature and therefore static electricity is developed which attracts dust, dirt etc. and the materials become dirty.· Sometimes due to over friction materials may be elongated.· Friction increases yarn hairiness.· Friction worn out parts of machine.

Minimization of friction intensity:  

1. Sizing is done in warp yarn before weaving to reduce frictional intensity. As a result, yarn damage will be reduced.

2. Emulsion, oil, lubricants etc. are specially applied on jute fiber to reduce friction.

3. Chemical treatment is done on wool fiber to reduce scale sharpness and thus reduce friction during processing.

4. By calendaring frictional intensity of cloth is reduced.

5. Sometimes resin finish is applied on fabric to reduce friction.