# GATE (TF) Textile 2022 Question Paper Solution | GATE/2022/TF/16

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###### Question 16 (Textile Technology & Fibre Science)

Molecular weight (g/mol) of polypropylene with a degree of polymerisation of 1000 (rounded off to nearest integer) is _.

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As we know,

Molecular formula of polypropylene=(C3H6)n

Molecular formula of repeat unit of polypropylene=C3H6

Molecular weight of repeat unit of polypropylene=3*12+6*1
=42
So, Molecular weight of repeat unit of polypropylene=42.0 g/mol

Molecular weight of polypropylene=Molecular weight of repeat unit of polypropylene x Degree of polymerisation
Molecular weight of polypropylene=42.0 x 1000

Molecular weight of polypropylene=42000 g/mol (Answer)

### What is degree of polymerisation ?

Degree of polymerization (DP) is a term used in polymer chemistry to describe the number of repeating units in a polymer chain. It is defined as the average number of monomer units that make up a single polymer chain.

The DP of a polymer is an important factor that affects its physical and chemical properties. In general, polymers with a high DP are more rigid, have a higher melting point, and are more resistant to chemical degradation than those with a low DP.
The DP of a polymer can be determined by various methods, including gel permeation chromatography, size exclusion chromatography, and end group analysis. The specific method used depends on the type of polymer being analyzed and the desired level of accuracy.

In the polymer industry, controlling the DP is important for producing high-quality polymer products with specific physical and chemical properties. For example, in the production of synthetic fibers, the DP of the polymer is carefully controlled to produce fibers with the desired tensile strength, elongation, and other physical properties.