Styrene Butadiene Rubber

26-Dec-13 1Made By Salem EL Feky & Kareem Tharaa

Introduction:

• Styrene-butadiene or styrene-butadiene

rubber (SBR) describe families of synthetic

rubbers derived from styrene and

butadiene.

• These materials have good abrasion

resistance and good aging stability when

protected by additives.

• About 50% of car tires are made from

various types of SBR

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Types of SBR:SBR is derived from two monomers, styrene and butadiene. The mixture of these two monomers are polymerized by two basically different processes: from solution (S-SBR) or as an emulsion (E-SBR).

1. Emulsion polymerization:E-SBR produced by emulsion polymerization is initiated

by free radicals.

2. Solution polymerizationSolution-SBR is produced by an anionic polymerization

process.

Buna S:The material was initially marketed with the brand name Buna S. Its

name derives Bu for butadiene and Na for sodium (natrium in several languages including Latin, German and Dutch), and S for styrene.

Made By Salem EL Feky & Kareem Tharaa26-Dec-13

Applications:1. The elastomer is used widely in pneumatic tires, shoe heels and soles, gaskets and even chewing gum. 2. It is a commodity material which competes with natural rubber. 3. Latex (emulsion) SBR is extensively used in coated papers, being one of the most cost-effective resins to bind pigmented coatings. 4. It is also used in building applications, as a sealing and binding agent behind renders as an alternative to PVA, but is more expensive.

Made By Salem EL Feky & Kareem Tharaa 426-Dec-13

Structure of Styrene-Butadiene:

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Molecular Formula:

C12 H14 Given That: C=12g/mol , H=1g/mol

The Molecular Weight=

(12*12)+(1*14)

=158g/mol

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Chemical Reaction:

Conditions:

• The ratio of butadiene to styrene is mostly

76.5% to 23.5% by weight.

• Temperature is normally about 50O

C or

even higher.

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Calculations:

n: Number Of Polymers Let n=100 Then 100*158= 15800 g/molTo Produce 100 Ton/Day

C4H6 + C8H8 C12H14

288 104 15800X Y 100*106

X= [(100*106 )*288]/15800 = 1.8*106 g/dayY= [(100*106 )*104]/104= 658.2*103 g/day

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Flow Sheet:

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