What are properties and Uses if Nylon 6? What do you mean by Saponnification number?
Uses of nylon 6 | Properties of nylon 6 | Saponification numbers:
Properties of nylon 6
1. The structure of nylons are linear that permits side‐by‐side alignment.
2. Due to hydrogen bonds they have high crystallinity which imparts :
(a) High strength (b) High melting point
(c) Elasticity (d) Toughness
(e) Abrasion resistance and retention of good mechanical properties up to 125 0 C.
3. They are also sterilizable.
4. They have good hydrocarbon resistance.
5. They have good moisture resistance.
Uses of Nylon 6:
1. It is primarily used for fibres which find use in making socks, carpets etc.
2. It is also used in mechanical engineering for well‐known applications like gears, bearing, bushes, cams etc.
3. It is also used for jacketing electrical ware to provide a tough, abrasion resistant outer cover to protect the primary electrical insulation.
Saponification value or number :
Saponification value or number of an oil is the number of milligram of potassium hydroxide required to saponify 1 gm of oil. (Saponification is the hydrolysis of an ester with KOH to give alcohol and sodium or potassium salt of the acid.)
Saponification number is determined by refluxing a known quantity of oil with a known excess of potassium hydroxide solution and titrating the unused alkali against an acid..
significance of Saponification numbers:
(i) As the saponification number is inversely proportional to molecular weight, hence average molecular weight of oil or fat can be found. The smaller the saponification value, the higher the molecular weight.
(ii) It also indicates the average length of the carbon chains of the fatty acid components.
(iii) Saponification number also gives an estimate of non‐fatty impurities present in oil or fat. Thus, we can find the extent of adulteration in an oil or fat.
(iv) As soap is formed in the product so saponification number also gives the actual amount of alkali required by triglyceride for its conversion to soap.
(v) Mineral oils do not undergo saponification but animal and vegetables oils undergo saponification. Hence, this gives an indication of the amount of animal and vegetables oils added to mineral oils to improve oiliness. This test also helps us to ascertain whether the oil under study is animal or vegetable or mineral or compounded oil.