Physico-Mechanical Characterization

Recommended Prerequisites

Not applicable.

Teaching Methods

The so called “theoretical” classes, besides providing opportunities for explaining and discussing concepts, have a component of real experimentation. This is based on the analysis and discussion of mechanical behaviours observed in materials in common use. In this way, through quick, simple, interactive experiments performed by the students in a traditional classroom, it is possible to illustrate and complement the concepts being analysed

Laboratory sessions are also planned, where several items of equipment will be used, specifically a differential scanning calorimeter, a dynamic mechanical analyser, a universal testing machine and an impact tester.

Learning Outcomes

The aim is that, on completion of the module, students will be able to:

- Describe the phenomenological nature of the crystalline and amorphous states in solid polymers, of glass transition and of melting.

- Interpret the influence of intrinsic and extrinsic factors on thermal transitions in polymer materials.

- Describe experimental methods for measuring thermal transitions and crystallinity content, and interpret their results.

- Describe the main types of mechanical test for solid polymers and interpret their results, relating them with the materials’ molecular structure.

- Interpret the influence of intrinsic and extrinsic factors on the mechanical behaviour of polymer materials.

- Describe how the performance of a polymer material can be changed through additivation, filling and blending.

- Identify physical and mechanical tests used in industry for the evaluation of relevant properties for specific applications.

Work Placement(s)

No

Syllabus

1. Physical properties of polymers in solid state Amorphous state properties, glass transition and secondary transitions. Properties of crystalline state, morphology of crystalline domains, melting temperature, factors that affect crystallinity content. Methods for experimental evaluation of thermal transitions and crystallinity

2. Transient mechanical tests Creep and relaxation tests. Models based on mechanical analogues. Boltzmann’s superposition principle. Regions of viscoelastic behaviour. Time-temperature equivalence

3. Dynamic mechanical tests Principles and forms of implementation.

4. Intrinsic and extrinsic factors that influence mechanical behaviour Crystallinity, cross-linking, strain rate, plasticizers, fillers, etc

5. Quasi-static tests Measurable properties in stress-strain tests. Yield and necking. Pre-fracture behaviours. Fragile and ductile fracture.

6.Other mechanical tests used in industry

Assessment Methods

Assessment
Data research on commercial equipment and methodologies for evaluation of certain physical and -mechanical properties: 40.0%
Testing and modelling of the viscoelastic behaviour of a polymer material: 60.0%

Bibliography

• Fried, Joel R.; Polymer Science & Technology, 3rd ed., Prentice-Hall, 2014.

• L. H. Sperling; Introduction to Physical Polymer Science, 4th ed., Wiley, 2006.

• Ward, I.M., Sweeney, J., An Introduction to the Mechanical Properties of Solid Polymers, 2nd ed., John Wiley & Sons, 2004.