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

Advantages of biliquid propellants over solid propellants, Advantages of Bi...

Advantages of Biliquid Propellants over Solid Propellants 1. The biliquid propellants generate higher thrust as compared to solid propellants. 2. The thrust produced by liqu

Wave length selectors, give exsample on how undesired wavelengths are block...

give exsample on how undesired wavelengths are blocked and desired one is trans mitted

What are acceptance tests?, What are Acceptance Tests? Acceptance test...

What are Acceptance Tests? Acceptance tests are used to evaluate product acceptability or liking or to determine which of a series of products is the most acceptable or the mo

Which quantum number will determine the shape the subshell, Which quantum n...

Which quantum number will determine the shape of the subshell: (1) Principal quantum number (2) Azimuthal quantum number (3) Magnetic quantum number (4)Spin quantum nu

Why alkylamines are stronger bases than arylamines, (a) Assign a reason for...

(a) Assign a reason for each of the following statements: (i) Alkylamines are stronger bases than arylamines. (ii) Acetonitrile Is preferred as solvent for carrying out sever

Borosilicate glass, Borosilicate glass: in this boric anhydride is used in...

Borosilicate glass: in this boric anhydride is used in place of lime. This glass generally contains 75-81% silica, 10-13.5% B 2 O 3 , 4.5-6% Na 2 O and 2-5% Al 2 O 3 . Sometimes Z

What are properties of ideal electrical insulating material, What are prope...

What are properties of an ideal electrical insulating material? The following are properties of an ideal (electrical) insulating material: (i)  Low  dielectric  court(high  die

Calculate the mole fraction of nh3, What will happen if you mix nitrogen an...

What will happen if you mix nitrogen and hydrogen gas at room temperature? Explain your reasoning. Calculate the mole fraction of NH 3 that would form theoretically at 298.15

Merits of atomic fluorescence spectrometry, Merits of Atomic fluorescence s...

Merits of Atomic fluorescence spectrometry: Merits of the technique involve extremely low detection limits for favourable elements and the possibility of handling solid, liqui

Reactivity, y LAH is strong reducing agent than NaBh4?

y LAH is strong reducing agent than NaBh4?

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