Processing Polymers Quiz

The function of the ejection system is to a. move the polymer melt into the mold cavity. b. open the mold halves after the cavity after cavity is filled. c. remove the molded parts from the runner system after molding d. separate the part from the cavity after molding e. none of the above

d. separate the part from the cavity after molding

The shear viscosity of a polymer melt is affected by which of the following a. Degree of polymerization b. polymer type c. rate of flow d. temperature e. All of preceding

All of the preceding

In rotational molding the centrifugal force is used to force the polymer melt against the surfaces of the mold cavity. True or False

False (its gravity, not centrifugal force)

Which of the three polymer types does not involve crosslinking? a. thermoplastics b. thermosets c. elastomers

Thermoplastics

Use of a parison is associated with which of the following plastic shaping processes. a. bi injection molding b. blow molding c. compression molding

blow molding

Which of the following processes are generally limited to thermoplastic polymers: (a) blow molding (b) compression molding (c) reaction injection molding

blow molding

Of the three polymers types, which is the most important commercially? a. thermoplastics b. thermosets c. elastomers

thermoplastics

Which of the following is not a section of a conventional extruder barrel for a thermoplastics a. compression b. die c. heating

die and heating

2. Which of the three polymer types is not considered to be a plastic?

elastomers

Which properties do plastic parts compare favorably with metals (a) impact resistance (b) resistance to ultraviolet radiation (d) strength

impact resistance

A thermoforming molding mold with convex form is called which of the following a. die b. female mold c. negative mold d. postive mold

positive mold

Spinning in the production of synthetic fibers refers to which of the following: a. extrusion of the plastic melt through small die openings. b. drawing the strands to elongate and thin them. c. both of the above d. none of the above

both of the above