Basic Viva for Textile Engineers (Fibre related)

1.         What is Fiber?
          Ans: Fiber, which is either spun (or twisted) into yarn or else directly compressed into fabric.

2.         Define ‘Natural fibers’?
          Ans: Natural fibers that occur in nature can be classified as vegetable, animal,  and mineral.

3.         Define ‘Man made fibers’?
          Ans: The natural material of cellulose has been taken from cotton linters and wood pulp,             processed chemically, and changed in form and several other characteristics into fibers of various lengths.

4.         Define mineral fibers?
          Ans: Glass fibers are produced by combining silica sand, limestone, and certain other minerals.

5.         Define metallic fibers?
          Ans: Produced by mining and refining fibers such metals as aluminum, silver, and gold.

6.         Define rubber fibers?
          Ans: Made from the sap tapped from the rubber tree.

7.         Name animal fibers.
          Ans: Wool, Silk, mohair.

8.         Name re-generated cellulosic fibers.
          Ans: Rayon, Acetate, Triacetate, viscose.

9.         Name of some vegetable fibers.
          Ans: Cotton, linen, jute, hemp.

10.      Name of some mineral fibers.
          Ans: Glass, ceramic, carbon

11.      What is cotton fiber?
          Ans: The cotton fiber grows in the seedpod, or boll or the cotton plant. Cotton fibre is a                polymer of cellulose.

12.      What is linen fiber?
          Ans: Linen fiber is obtained from the stoke of the flax plant linen yarn can be very strong and lustrous and in used for apparel, have furnishings and upholstery.

13.      What is silk fiber?
          Ans: Is a fine continuous strand unwound from the cocoon of a moth caterpillar known as the silkworm. Silk is composed of protein. Lustrous, smooth, lightweight, strong, and elastic. Used for apparel home furnishings, and upholstery.

14.      What is nylon?
          Ans: Nylon is thermoplastic, resilient, elastic and very strong. It is used for a wide variety of apparel, have furnishings and industrials products.

15.      What is polyester?
          Ans: Polyester fibers are thermoplastic, they have good strength and are hydrophobic, do not absorb water well. Used for a wide variety of apparel, home furnishings, and industrial fabrics.

16.      Define spandex?
          Ans: Spandex fibers are extremely elastic. They are used for such purpose as foundation             garments, hosiery, swimwear and sportswear.



17.      What is the standard of cotton yarn count?
          Ans: The standard for the yarn count in cotton is I pound of fiber drawn out to make 840              yards of yarn. The resultant thickness or size is known as count number 1 or Ne1.

18.      What is ply yarns?
          Ans: Two or more strands or yarns are twisted together; they are designed as ply yarns.

19.      What is ASTM?
          Ans: American Society for Testing and Materials.

20.      What is ISO?
          Ans: International Organization for Standardization.

21.      What is ANSI?
          Ans: American National Standards Institute.

22.      What is the meaning of AFIS?
          Ans. Advanced fiber information system.

23.      What is ICS?
          Ans: Integrated Composite Spinning 84

24.      What do you mean by WIRA?

Ans. Wool International Research Association.

25.      How many fibers can you yield from each cotton seed?
          Ans: Each cottonseed may produce as many as 20,000 fibers on its surface, and a single ball         will contain around 150,000 fibers.

26.      Name some species of cotton
o    Ans: Gossypium harbaceum
o    Gossypium hirsutum
o    Gossypium peruvianum
o    Gossypium barbedense

27.      What is the Monomer of cotton
          Ans: cotton is made of cellulose and its monomer is glucose.

28.      Write down the moisture regain of cotton fibre?
          Ans. 8.5%

29.      The formula of cellulose.
Ans: C6H10O5

30.      The formula of glucose.
          Ans: C6H12O6

31.      What is viscose?
          Ans: Viscose is regenerated cellulose

32.      Natural fibres are hydrophilic in nature? (Yes/No)
          Ans. Yes.

33.      Manmade fiber are hydrophobic in nature(yes/no)?
          Ans. Yes.

34.      What are the long staple fiber?
          Ans. Jute, wool, flax, hemp.

35.      What is MR% of jute?
          Ans. 13.75

36.      What is MR% of viscose and silk?
          Ans. 11.0

37.      What is MC % of cotton?
          Ans. 7.834

38.      What is MR% of wool?
          Ans. 16.0

39.      What is MR% of nylon?
          Ans. 4.0

40.      What is MR% of polyester?
          Ans. 0.4

41.      Cotton is dissolved into 70% H2SO4(yes/no)?
          Ans. Yes

42.      Viscose is dissolved into 35% H2SO4(yes/no)?
          Ans. Yes

43.      Nylon is dissolved into 20% HCL/phenol(yes/no)?
          Ans. Yes

44.      Polyester is dissolved into 100% nitro benzene at 100℃ (yes/no)?
          Ans. Yes.

45.      Burning smell of cotton is like as burning paper(yes/no)?
          Ans. Yes.

46.      How polyester fibre form?
          Ans: To form polyester, dimethyl terephthalate is first reacted with ethylene glycol in the presence of a catalyst at a temperature of 302-410°F (150-210°C). The resulting chemical, a monomer (single, non-repeating molecule) alcohol, is combined with acid and raised to a temperature of 472°F (280°C). Newly-formed polyester, which is clear and molten, is extruded through a slot to form long ribbons.