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

Find the value of limiting molar conductivity, (a) Describe how you would c...

(a) Describe how you would carry out a series of experiments to determine the molar conductivities (Λ m ) of an electrolyte at various concentrations, starting with the measurement

Goc, homolytic fission

homolytic fission

Find the ph value, 50ml of 0.1M NH 4 OH ,25ml NH 4 Cl weere used to make a ...

50ml of 0.1M NH 4 OH ,25ml NH 4 Cl weere used to make a buffer . what is the PH is if Pk b is 4.8? Solution) The given buffer is a base buffer [NH4OH] =[(50*0.1)/75] [NH4Cl] =[(

Light waves, uses of light waves in chemical areas

uses of light waves in chemical areas

#title. PROPERTIES, what is chemical properties of p block elements

what is chemical properties of p block elements

Addition catalysed by base - aldehydes and ketones, Addition catalysed by b...

Addition catalysed by base - Aldehydes and Ketones In the existence of a base one equivalent of an alcohol reacts along with only one equivalent of the carbonyl compound. The p

Unsaturated dicarboxylic acids, Unsaturated dicarboxylic acids The mole...

Unsaturated dicarboxylic acids The molecular formula of the simplest unsaturated dicarboxylic acid is HOOC.CH=CH.COOH This formula, however represents two chemical compounds, m

Radioactive decay, Q. in radioactive decay, a nucleus emits an alpha partic...

Q. in radioactive decay, a nucleus emits an alpha particle and two beta particle successively. show that the final nucleus is an isotope of original nucleus. Ans: Let the mass and

The p-block elements, what are the chemical reactionsof the p-block element...

what are the chemical reactionsof the p-block elements

Gas stoichiometry, dry air near sea level has the following composition by ...

dry air near sea level has the following composition by volume N2=78.08 percent,O2=20.94 percent. Calculate the partial pressure of each gas if atmospheric pressure is 1.00 atm

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