Numerical methods & Viscoelastic models of Elastomers — Summer 2023

What do you mean by Elasticity?

State the Hook’s law with suitable example.

Discuss the Bulk modulus and Young modulus in detail.

Derive the equation for the entropy generated force in polymer chain.

Define the term Viscosity & Write it’s Nomenclature.

List out the different viscometers and explain any one in detail.

Explain the “Theory of Viscosity”.

State the Newton’s law of viscosity with its derivation.

Give the comparison of Time dependent & Time independent non Newtonian fluid.

Write a short note on “Viscoelastic fluids.”

What is the difference between Thixotropic and Rheopectic fluid?

List out the classification of fluids and explain any one in brief.

Explain the Pseudoplastic, Dilatant and Bingham plastic fluids in detail.

Give the disadvantages of Maxwell model.

Derive the stress relaxation experiment equation for Maxwell Model.

Discuss the Four parameter model in detail.

Derive the creep experiment equation for Voight model.

Explain a brief note on Deborah number.

Apolystyrene sample of 0.02/m2 cross-sectional area is subjected to a creep load of 105 N. The load is removed after 30 s. Assuming that the Maxwell element accurately describes the behavior of polystyrene and that viscosity is 5×1010 P, while Young’s modulus is 5× 105 psi, calculates: (i) The compliance (ii) The deformation recovered on the removal of the dead load (iii) The permanent

What is the Tg of polystyrene of Mn = 3000? Where K= 2x105.

List out the factors affecting Glass transition temperature.

How chain flexibility and Plasticizer and pendent group affect the glass transition temperature? Explain in detail.

Why polyethylene have (-120°C Tg) glass transition temperature?

Toluene behaves as a plasticizer for polystyrene. Estimate Tg of a polystyrene sample containing 20 vol% toluene.

Describe the transitions and associated properties with respect to glass transition temperature.