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

Classification of polymers - on the basis of structure, Classification of p...

Classification of polymers - On the basis of structure On the basis of structure of polymers these can be classified as (i) Linear polymers      (ii) Branched chain polym

Normality, I don''t understand the concept of normality and gram equivalent...

I don''t understand the concept of normality and gram equivalent

Find relation between solute standard state and henry''s law, Find Relation...

Find Relation between Solute Standard State and Henry's Law? For a solution process in which species B is transferred from a gas phase to a liquid solution, find the relation b

Explain ethanolysis, Explain Ethanolysis Ethanolysis of the acetal link...

Explain Ethanolysis Ethanolysis of the acetal linkage occurs in ethanol just as hydrolysis occurs in water.  An ethyl pyranoside is also produced from the glucose residue at th

Precipitation titrations - types of titrations, Precipitation titrations - ...

Precipitation titrations - Types of titrations The titrations that are based upon the formation of insoluble precipitates, while the solvent of two reacting solution are brough

Redox reaction, the set of numerical coefficients in the equation K2CrO4+HC...

the set of numerical coefficients in the equation K2CrO4+HCl=K2Cr2O7+KCl is

Mining of petroleum and petroleum refining, Mining of petroleum and Petrole...

Mining of petroleum and Petroleum refining (1) Mining of petroleum: Petroleum deposits takes place at varying depth at different places ranging from 500 to 15000 feet. This is

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