Natural rubber, Chemistry

Assignment Help:

Natural rubber: Natural rubber is obtained by making small incisions on the bark of certain types of trees, like "Have a brasiliensis" and "Ganynle". White milky liquid substance (rubber latex) from the rubber tree by tapping is obtained. Latex is sieved to remove impurities then coagulated using coagulants like acetic acid or formic acid. Coagulated mass convert into coagulum. Coagulum is washed, dried and treated as follows:

1. Copper rubber: It is prepared by adding, little amount of sodium bisulphite, a retarder prevents, the discoloration and softening of rubber. Coagulum is allowed to drain for about two hours and after that it is passed through a creeping machine to form sheets of rubber of about 1 mm.

2. Smoked sheet: For preparing smoked sheets coagulation is carried out in long tanks. Sides of the tank have vertical grooves fitted with metal plates. First, dilute latex is added into the tanks and before that plates are removed. Coagulating agent, formic acid or acetic acid is then added and mixture is thoroughly stirred then plates are fitted and allowed to dry slabs are formed.

 

 


Related Discussions:- Natural rubber

Crystal field splitting in tetrahedral field, Q. Crystal Field Splitting in...

Q. Crystal Field Splitting in Tetrahedral Field? A tetrahedron can be viewed as a part of cube where the metal ion occupies the centre of the cube and the four ligands are plac

Electrochemical thermodynamics, ELECTROCHEMICAL  THERMODYNAMICS Nota...

ELECTROCHEMICAL  THERMODYNAMICS Notation: To avoid repetitive drawing of complicated cells diagram, a common notation has been adopted for cells. All electrical contacts

What is the electrometallurgy, Q. What is the Electrometallurgy? The ab...

Q. What is the Electrometallurgy? The above two metallurgical processes, namely pyrometallurgy and hydrometallurgy can be used in the extraction of a fairly large number of met

Which statement is not correc, Which statement is not correct for n=5, m=3:...

Which statement is not correct for n=5, m=3: (1) l=4                    (2) l=0, 1.3, s =+1/2            (3) l= 3                  (4) All are correct Ans:l=4

Describe, describe the reaction and constitution of glucose.

describe the reaction and constitution of glucose.

S block elements.., lithium and beryllium markedly differ from other member...

lithium and beryllium markedly differ from other members of their respective groups.

Formaldehyde, Ask question formaldehyde reacts with NH3 #Minimum 100 words ...

Ask question formaldehyde reacts with NH3 #Minimum 100 words accepted#

Acidity, Why alcoholic acidity of maids is expressed as H2SO4?

Why alcoholic acidity of maids is expressed as H2SO4?

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd