Which of the following processing methods would you use for compounding a polymer with colorants and stabilizers a) injection moulding b) thermoforming c) single-screw extrusion d) twin-screw extrusion e) transfer moulding.

a. Discuss the relative importance. Is it very important, somewhat important or not important? b. How does the viscosity of a polymer affect the printability and the print quality? c. What is a typical range of viscosity for successful 3-D printing?

3. Sketch and compare Edge and screw dislocations and give main the differences between them.

how does the flash drum sizing affect the performance of the product

The pattern or decoration becomes part of the plastics article as it is fused by heat and pressure of the plastics material during ______ decorating.

Explain what composite materials are and what characteristics they must have.

What is meant by loading in adsorption?

3. Describe what happens to the grain structure, strength, and ductility of brass when it is cold worked. What is the expected yield strength of brass after 30% cold working?

7 -------------centrifuge is the most suitable for separation of non-friable crystals. Tubular bowl Disc-bowl Perforated horizontal basket continuous Suspended batch basket

17.5. Identify the following polymer processing techniques as either: (i) Continuous (able to operate for very long periods of time as long as enough polymer is supplied), (ii) Batch or semi-continuous (able to make one material at a time, or possibly operate in a cyclic or fashion for a long time with small breaks between processing) THERMAL EXTRUSION CASTING TO FORM A THERMOSET POLYMER BLOW MOLDING MELT SPINNING OF FIBERS THERMOFORMING - INJECTION MOLDING - BLOW EXTRUSION - CALENDERING - COMPOUNDING - ROTATIONAL MOLDING 17.6. You work at a plant that makes poly(ethylene terephthalate), PET, bottles using blow molding, but the production line is having a problem with lots of rejected bottles, which must be ground up and recycled. The rejected bottles sometimes have holes in the threaded part at the top of the bottle (where the screw-cap goes), or this part is often too thin and not rigid enough for the screw cap to fit snugly. A. Give a likely explanation of what is causing the…