MATL07027 2019 Polymer Processing

Demonstrate a basic knowledge and understanding of the principles of Rheology.

Demonstrate knowledge, understanding, and practical experience of the extrusion process including compounding, sheet production, and profile production.

Demonstrate knowledge, understanding, and practical experience of the injection moulding process.

Demonstrate a thorough knowledge of the effect that material properties have on melt processing conditions.

Communicate effectively in written form.

This module will be assesed by way of assignments, practical assessment and a final examination.

Rheology

Overview of the principle of flow and viscosity by evaluating the effects of structure property relations under conditions of temperature and pressure.

Mixing and Compounding

Introduction to basic principles of mixing; choice and comparison of mixing and compounding systems for specific materials and applications

Extrusion

Basic screw types for single screw extruders, vented extruders. Overview of the main extrusion processes: tube, wire coating, sheet and film. Design of mixing heads for single screw extrusion. Coextrusion process. Comparison with twin screw extrusion. Introduction to screw and die characteristics. Fault diagnosis of common processing problems. Basic screw and die design considerations.

Injection Moulding

Construction of machines and types available: hydraulic, electric and hybrid systems. Multi-shot systems and micro machines. Types of mould locking systems and tie bar less machines. Screw designs. Moulding cycle. Overview of injection moulding non-standard materials such as elastomers and thermosets. The effects of moulding conditions and process variables on products e.g. shrinkage and orientation. Systematic approach to correction of moulding faults. The economics of injection moulding: The moulding cycle and the derivation of typical costings for moulded components. Heating and cooling requirements. Machine safety: requirements and types of safety mechanisms.

Blow Moulding

Principles of injection and extrusion blow moulding. Parison formation. Blowing systems. The effect of material properties on the product, also the effect of processing on the product.

Characterisation Techniques

Case studies on industry problems and how they were solved using thermal, mechanical and spectroscopy techniques.

Practical Content

Determination of the optimum moulding area diagram for a range of engineering materials.

Compounding polymer/nano clays composites with and without binding agents .

Effect of extrusion variables on the dimensions of an extruded profile.

Blending and injection moulding rubber/polymer compounds to enhance material properties.