Jute Fibre

 

Define Bast Fibres
Bast fibres are plant fibres collected from the phloem (inner bark) or skin of the plant stem. These fibres provide structural support to the plant and are extracted through processes such as retting. Examples include jute, flax, hemp, and kenaf.

Classify Jute Fibre Based on Growing Area in Bangladesh
Jute fibre in Bangladesh is classified based on the growing regions:

• Jat Area Jute: Grown in the northern and eastern parts, especially in Mymensingh and Jamalpur. Known for high-quality fibres.

• District Area Jute: Cultivated in regions like Faridpur, Kushtia, Jessore. Good quality with moderate fineness.

• Bhawal Area Jute: Found in areas like Tangail and Gazipur. Generally coarser and lower grade compared to Jat jute.

Explain the Morphological Diagram of Jute Fibre
The morphological structure of jute fibre includes:

• Cuticle: Waxy outer layer

• Primary Wall: Composed of hemicellulose and pectin

• Secondary Wall: Rich in cellulose and lignin, providing strength

• Lumen: Central hollow canal
  (Diagram should show a cross-section and longitudinal view of jute fibre with labeled parts.)

Explain the Chemical Structure and Chemical Composition of Jute Fibre
Jute fibre primarily consists of:

• Cellulose: 60–65%

• Hemicellulose: 20–25%

• Lignin: 10–12%

• Pectin, waxes, and proteins: ~3–5%
  The structure comprises long chains of β-D-glucose units forming cellulose microfibrils embedded in a matrix of hemicellulose and lignin.

Describe the Retting Process of Jute Fibre
Retting is the process of rotting the jute stalks to separate the fibres. Common retting methods include:

• Water Retting: Bundles are submerged in stagnant or slow-moving water.

• Ribbon Retting: Only the bark is retted after being stripped from stalks.

• Chemical Retting: Uses mild chemicals to speed up fibre separation.

• Enzyme Retting: Environmentally friendly method using microbial enzymes.

Discuss the Grading of Jute Fibre
Jute is graded based on:

• Fineness

• Strength

• Color/lustre

• Length

• Root content
  Grades include: Top, Middle, B, C, and X grades.

Explain the Effect of Lignin in Jute Fibre
Lignin provides rigidity and stiffness to the fibre but reduces flexibility. High lignin content can make processing and dyeing more difficult, affecting softness and spinnability.

Mention the Defects and Causes of Jute Fibre

• Over-retting: Weak fibres due to prolonged retting

• Under-retting: Hard, coarse fibres due to insufficient retting

• Rooty Fibre: Presence of lower portion of stalk with low-quality fibre

• Entangled Fibre: Poor extraction or handling

• Dark or Discolored Fibre: Caused by poor retting water or fungal attack

Describe the Physical & Chemical Properties of Jute Fibre

• Physical Properties:

  • Coarse and rough texture

  • Golden shine (in high-quality jute)

  • High tensile strength

  • Low elongation

  • Biodegradable and breathable

• Chemical Properties:

  • Reacts with strong alkalis and acids

  • Can be dyed with direct, vat, and reactive dyes

  • Absorbs moisture easily

  • Degrades under UV exposure over time

Mention the End Uses of Jute Fibre

• Sacks and bags

• Carpets and rugs

• Ropes and twines

• Geotextiles

• Home decorators (mats, curtains, wall hangings)

• Eco-friendly packaging

• Composite materials and automotive interiors