Plastic systems MCQs With Answer

Plastic systems MCQs With Answer provide B. Pharm students a focused review of polymers used in pharmaceutical formulations, packaging, and medical devices. This introduction covers polymer classification, mechanical and barrier properties, additives (plasticizers, stabilizers), analytical methods (DSC, TGA, FTIR, GPC), sterilization effects, leachables/extractables, and regulatory considerations. Understanding polymer behavior—glass transition, crystallinity, permeability, and processing methods like extrusion, injection and blow molding—is essential for drug stability, compatibility, and safe packaging selection. These MCQs emphasize real-world applications in drug delivery, aseptic packaging and material selection for parenterals to build practical exam readiness. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. What does the glass transition temperature (Tg) of a polymer represent?

• The temperature at which polymer decomposes
• The temperature at which crystalline regions melt
• The temperature where amorphous regions transition from glassy to rubbery
• The temperature where polymer becomes electrically conductive

Correct Answer: The temperature where amorphous regions transition from glassy to rubbery

Q2. What is the primary role of plasticizers in pharmaceutical plastics?

• Increase crystallinity
• Lower glass transition temperature and increase flexibility
• Act as disinfectants
• Serve as UV stabilizers

Correct Answer: Lower glass transition temperature and increase flexibility

Q3. Which polymer is most commonly used for traditional blister pack thermoforming?

• Polyvinyl chloride (PVC)
• Polyethylene terephthalate (PET)
• Polypropylene (PP)
• Polytetrafluoroethylene (PTFE)

Correct Answer: Polyvinyl chloride (PVC)

Q4. Which analytical technique is most used to determine Tg and melting transitions of polymers?

• Thermogravimetric analysis (TGA)
• Differential scanning calorimetry (DSC)
• Fourier-transform infrared spectroscopy (FTIR)
• Gel permeation chromatography (GPC)

Correct Answer: Differential scanning calorimetry (DSC)

Q5. Which processing condition typically increases polymer crystallinity?

• Rapid quenching from the melt
• Annealing or slow cooling
• Exposure to gamma radiation
• Adding plasticizer

Correct Answer: Annealing or slow cooling

Q6. Which material provides the best oxygen barrier when used as a thin layer in multilayer films?

• Low-density polyethylene (LDPE)
• Polyvinylidene chloride (PVDC)
• Ethylene vinyl alcohol (EVOH)
• Polystyrene (PS)

Correct Answer: Ethylene vinyl alcohol (EVOH)

Q7. Melt flow index (MFI) of a thermoplastic is a measure of:

• Glass transition temperature
• Molecular weight distribution directly
• Flowability of the polymer melt under standardized conditions
• Degree of crystallinity

Correct Answer: Flowability of the polymer melt under standardized conditions

Q8. Which sterilization method is most likely to cause polymer chain scission and embrittlement?

• Autoclaving at 121°C
• Ethylene oxide (EO) sterilization
• Gamma irradiation
• Dry heat sterilization

Correct Answer: Gamma irradiation

Q9. In pharmaceutical packaging, what are “leachables”?

• Compounds intentionally added as APIs
• Compounds that migrate into the drug product during shelf life
• Volatile solvents used in manufacturing
• Microbial contaminants from packaging

Correct Answer: Compounds that migrate into the drug product during shelf life

Q10. Which biodegradable polymer is widely used for resorbable implants and controlled drug delivery?

• Polyethylene (PE)
• Poly(lactic-co-glycolic acid) (PLGA)
• Polyvinyl chloride (PVC)
• Polystyrene (PS)

Correct Answer: Poly(lactic-co-glycolic acid) (PLGA)

Q11. Which additive class is specifically used to protect plastics from UV-induced degradation?

• Plasticizers
• UV stabilizers or HALS (hindered amine light stabilizers)
• Flame retardants
• Antimicrobials

Correct Answer: UV stabilizers or HALS (hindered amine light stabilizers)

Q12. Which term best describes a polymer’s resistance to flow under applied stress?

• Crystallinity
• Tg
• Viscosity
• Permeability

Correct Answer: Viscosity

Q13. Which technique is most appropriate to identify functional groups and chemical bonds in a polymer?

• Gel permeation chromatography (GPC)
• Fourier-transform infrared spectroscopy (FTIR)
• Melt flow index (MFI)
• Universal testing machine

Correct Answer: Fourier-transform infrared spectroscopy (FTIR)

Q14. Why is residual monomer testing important for pharmaceutical plastics?

• Residual monomer improves mechanical strength
• Residual monomer can affect drug stability and pose toxicity
• Residual monomer increases barrier properties
• Residual monomer acts as a plasticizer

Correct Answer: Residual monomer can affect drug stability and pose toxicity

Q15. Which polymer is commonly used for disposable syringes due to chemical resistance and heat tolerance?

• Polypropylene (PP)
• Polystyrene (PS)
• Polyvinyl chloride (PVC)
• Polytetrafluoroethylene (PTFE)

Correct Answer: Polypropylene (PP)

Q16. Which material has been traditionally used for IV infusion bags but is facing replacement due to leachable concerns?

• Polyethylene terephthalate (PET)
• Polyvinyl chloride (PVC)
• Polylactic acid (PLA)
• Polypropylene (PP)

Correct Answer: Polyvinyl chloride (PVC)

Q17. Oxygen transmission rate (OTR) testing primarily evaluates a material’s:

• Mechanical strength
• Barrier property to oxygen permeation
• Surface wettability
• Thermal decomposition

Correct Answer: Barrier property to oxygen permeation

Q18. Which of the following is a commonly used pharmaceutical-grade plasticizer?

• Di(2-ethylhexyl) phthalate (DEHP)
• Triethyl citrate
• Butylated hydroxytoluene (BHT)
• Polytetrafluoroethylene (PTFE)

Correct Answer: Triethyl citrate

Q19. Which polymer is amorphous, highly transparent and commonly used for clear pharmaceutical packaging?

• High-density polyethylene (HDPE)
• Polyethylene terephthalate (PET)
• Polypropylene (PP)
• Polyvinylidene fluoride (PVDF)

Correct Answer: Polyethylene terephthalate (PET)

Q20. Glass transition temperature (Tg) primarily affects which property of a polymer at room or body temperature?

• Electrical conductivity
• Mechanical flexibility and toughness
• Color stability
• Flavor masking

Correct Answer: Mechanical flexibility and toughness

Q21. Why is ethylene oxide (EO) sterilization preferred for many heat-sensitive plastic medical devices?

• It uses high-temperature steam
• It is a low-temperature gaseous method compatible with many plastics
• It causes minimal microbial killing
• It always leaves no residues

Correct Answer: It is a low-temperature gaseous method compatible with many plastics

Q22. Which joining method is commonly used for high-speed assembly of blister and pouch packaging?

• Soldering
• Ultrasonic welding
• Riveting
• Solvent welding in open air

Correct Answer: Ultrasonic welding

Q23. Tensile strength of a polymer is most directly measured using:

• Universal testing machine (tensile tester)
• Differential scanning calorimetry (DSC)
• Thermogravimetric analysis (TGA)
• Fourier-transform infrared spectroscopy (FTIR)

Correct Answer: Universal testing machine (tensile tester)

Q24. Which antioxidant is widely used to protect plastics from thermal oxidation?

• Butylated hydroxytoluene (BHT)
• Triethyl citrate
• Polyethylene glycol (PEG)
• Ethylene oxide

Correct Answer: Butylated hydroxytoluene (BHT)

Q25. Which hydrophilic polymer is commonly used as a binder and film former in oral formulations?

• Polyvinylpyrrolidone (PVP)
• Polylactic acid (PLA)
• Polypropylene (PP)
• Polytetrafluoroethylene (PTFE)

Correct Answer: Polyvinylpyrrolidone (PVP)

Q26. Which of these is a thermoset polymer used in rigid, heat-resistant components?

• Polyethylene (PE)
• Polypropylene (PP)
• Epoxy resin
• Polyethylene terephthalate (PET)

Correct Answer: Epoxy resin

Q27. Which polymer shows exceptional chemical resistance and is used for linings and seals?

• Polyethylene (PE)
• Polyvinyl chloride (PVC)
• Polytetrafluoroethylene (PTFE)
• Polyethylene terephthalate (PET)

Correct Answer: Polytetrafluoroethylene (PTFE)

Q28. Which factor most increases the migration rate of additives from plastic into a drug product?

• Lower temperature
• Reduced surface area
• Higher temperature
• Increased crystallinity

Correct Answer: Higher temperature

Q29. Which analytical method measures polymer mass loss as a function of temperature to assess thermal stability?

• Differential scanning calorimetry (DSC)
• Thermogravimetric analysis (TGA)
• Fourier-transform infrared spectroscopy (FTIR)
• Gel permeation chromatography (GPC)

Correct Answer: Thermogravimetric analysis (TGA)

Q30. Loss of plasticizer from a polymer typically results in:

• Increased flexibility
• Embrittlement and loss of flexibility
• Improved barrier properties
• Lower glass transition temperature

Correct Answer: Embrittlement and loss of flexibility

Q31. Which polymer family contains ester linkages in its backbone?

• Polyethylene (PE)
• Polyesters such as PET or PLA
• Polypropylene (PP)
• Polytetrafluoroethylene (PTFE)

Correct Answer: Polyesters such as PET or PLA

Q32. Which regulatory body commonly provides guidance on materials in contact with pharmaceuticals in the United States?

• World Health Organization (WHO)
• Food and Drug Administration (FDA)
• European Medicines Agency (EMA)
• Japanese Pharmacopeia only

Correct Answer: Food and Drug Administration (FDA)

Q33. In thermoforming blister manufacture, which property of the polymer sheet is most critical to achieving accurate part geometry?

• Thermoformability and melt viscosity at forming temperature
• Electrical conductivity
• Optical birefringence
• Magnetic susceptibility

Correct Answer: Thermoformability and melt viscosity at forming temperature

Q34. Which polymer class (brand) is increasingly used for high-performance parenteral containers due to low extractables and good clarity?

• Polyvinyl chloride (PVC)
• Cyclic olefin copolymer (COC/COP)
• Low-density polyethylene (LDPE)
• Polystyrene (PS)

Correct Answer: Cyclic olefin copolymer (COC/COP)

Q35. Extractables studies for pharmaceutical plastics are typically performed using which approach?

• Mechanical testing only
• Solvent extraction followed by analytical characterization
• Visual inspection
• Tensile testing

Correct Answer: Solvent extraction followed by analytical characterization

Q36. Increasing the average molecular weight of a polymer generally leads to:

• Lower tensile strength
• Higher tensile strength and toughness
• Higher volatility
• Lower melt viscosity

Correct Answer: Higher tensile strength and toughness

Q37. Which technique is used to measure molecular weight distribution of synthetic polymers?

• Size-exclusion chromatography / Gel permeation chromatography (GPC)
• Thermogravimetric analysis (TGA)
• Ultrasonic welding
• Oxygen transmission rate (OTR)

Correct Answer: Size-exclusion chromatography / Gel permeation chromatography (GPC)

Q38. Which polymer is widely used for high-density, chemically resistant pharmaceutical containers like jerrycans?

• Low-density polyethylene (LDPE)
• High-density polyethylene (HDPE)
• Polystyrene (PS)
• Polyethylene terephthalate (PET)

Correct Answer: High-density polyethylene (HDPE)

Q39. For sterile barrier systems, which property of the package seal is most critical?

• Color matching
• Seal strength and integrity
• Electrical resistivity
• Magnetic permeability

Correct Answer: Seal strength and integrity

Q40. Which additive class is specifically formulated to improve polymer heat stability during processing?

• Heat stabilizers
• Plasticizers
• Fillers for opacity
• Colorants

Correct Answer: Heat stabilizers

Q41. Which analytical technique is most appropriate for identifying volatile organic extractables from a plastic into a solvent?

• Liquid chromatography with UV detection (HPLC-UV)
• Gas chromatography–mass spectrometry (GC-MS)
• Universal testing machine
• Thermogravimetric analysis (TGA)

Correct Answer: Gas chromatography–mass spectrometry (GC-MS)

Q42. How does decreasing polymer crystallinity typically affect gas permeability?

• Decrease permeability
• No effect on permeability
• Increase permeability
• Eliminate permeability

Correct Answer: Increase permeability

Q43. Which biodegradable polymer is commonly used for absorbable surgical sutures?

• Poly(glycolic acid) (PGA)
• Polyethylene (PE)
• Polyvinyl chloride (PVC)
• Polystyrene (PS)

Correct Answer: Poly(glycolic acid) (PGA)

Q44. Contact angle measurements on a polymer surface primarily assess which characteristic?

• Thermal stability
• Surface wettability and energy
• Molecular weight
• Glass transition temperature

Correct Answer: Surface wettability and energy

Q45. Which processing method is used to manufacture hollow plastic bottles and containers?

• Injection molding
• Blow molding
• Compression molding
• Extrusion without molding

Correct Answer: Blow molding

Q46. A decrease in measured Tg of a polymer formulation most often indicates:

• Crosslinking has increased
• Plasticization or addition of a low Tg component
• Increased crystallinity
• Thermal degradation only

Correct Answer: Plasticization or addition of a low Tg component

Q47. What is a major health concern associated with some phthalate plasticizers historically used in medical plastics?

• Acute bacterial infection
• Potential endocrine disruption and reproductive toxicity
• Improved barrier to oxygen
• Enhanced mechanical strength

Correct Answer: Potential endocrine disruption and reproductive toxicity

Q48. The oxygen barrier performance of EVOH layers in packaging diminishes significantly with:

• Decreasing temperature
• Increasing humidity due to water uptake
• Exposure to vacuum
• Thin reduced layer thickness only

Correct Answer: Increasing humidity due to water uptake

Q49. Which polymer is commonly used as a film former for oral thin films and has mucoadhesive properties?

• Hydroxypropyl methylcellulose (HPMC)
• Polytetrafluoroethylene (PTFE)
• Polyethylene terephthalate (PET)
• Polystyrene (PS)

Correct Answer: Hydroxypropyl methylcellulose (HPMC)

Q50. To improve oxygen barrier of a multilayer pharmaceutical film without greatly increasing thickness, formulators commonly:

• Add more plasticizer to the outer layer
• Include an EVOH or high-barrier polymer layer
• Reduce the number of layers
• Switch to polystyrene as the core

Correct Answer: Include an EVOH or high-barrier polymer layer

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com