Practice Exam Questions And Correct

Ohio Plastics Processing Technician Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2025|2026 Q&A | Instant Download Pdf

• Which process involves heating plastic until it becomes pliable and

then forcing it through a shaped die?

• Injection molding
• Blow molding
• Extrusion
• Rotational molding

Rationale: Extrusion involves heating plastic to a molten state and

forcing it through a die to create continuous shapes.

• What is the main purpose of a mold release agent?
• To improve plastic strength
• To prevent plastic from sticking to the mold 1 / 4

• To add color to plastic
• To reduce shrinkage

Rationale: Mold release agents create a barrier between the plastic

and mold, making demolding easier.

• Which thermoplastic is commonly used for food containers due to its

chemical resistance?

A. PVC

• Polystyrene
• Polypropylene (PP)
• Nylon

Rationale: Polypropylene is widely used in food packaging because it

resists many chemicals and has a high melting point.

• What does the term “thermoset” mean?
• Can be melted and reshaped multiple times
• Cures into a permanent shape that cannot be remelted
• Is biodegradable
• Has a low melting point

Rationale: Thermosets undergo a chemical reaction that

permanently hardens them, so they cannot be remelted.

• Which plastic processing method is best suited for hollow products

like bottles?

• Extrusion
• Blow molding 2 / 4

• Injection molding
• Compression molding

Rationale: Blow molding is used to create hollow parts by inflating a

heated plastic parison inside a mold.

• What is the main function of a hopper in an injection molding

machine?

• To heat the plastic
• To compress the mold
• To feed plastic pellets into the machine
• To eject finished parts

Rationale: The hopper stores and feeds raw plastic pellets into the

machine for melting and molding.

• Which defect occurs when air is trapped inside the molded part?
• Sink marks
• Warpage
• Voids
• Flash

Rationale: Voids are internal cavities caused by trapped air or gas

during molding.

• What property is measured by a material’s melt flow index (MFI)?
• Hardness
• Flowability of molten plastic
• Impact resistance 3 / 4

• Tensile strength

Rationale: MFI measures how easily a plastic flows when melted,

important for processing selection.

• What is the main advantage of using computer-controlled injection

molding machines?

• Reduced material cost
• Improved precision and repeatability
• Higher molding temperature
• Faster cooling

Rationale: CNC-controlled machines provide precise control over

parameters, producing consistent parts.

• Which additive is used to make plastics more flexible?
• Stabilizer
• Plasticizer
• Filler
• Lubricant

Rationale: Plasticizers soften plastics, increasing flexibility and

reducing brittleness.

• Which polymer is known for its excellent impact resistance and

is often used for automotive parts?

A. PVC

• Polystyrene
• ABS (Acrylonitrile Butadiene Styrene)
• / 4