Why Isn't Cling Wrap as Good as It Used to Be?

The video discusses the history and changes in cling wrap, focusing on Saran Wrap. Originally made from PVDC, a highly effective polymer, it was changed to polyethylene due to environmental concerns. This change reduced its effectiveness in trapping odors and preserving freshness. Despite the decline in performance, the switch was made to reduce toxic pollutants.

What was the main reason SC Johnson changed the formula of Saran Wrap in the early 2000s?

• To improve its stickiness

• To reduce production costs

• To address environmental concerns

• To enhance its odor-trapping ability

What is the primary chemical compound that made the original Saran Wrap effective?

• Polyvinylidene chloride (PVDC)

• Polystyrene

• Polyethylene

• Polypropylene

Why was PVDC particularly useful for food preservation?

• It was biodegradable

• It had a high permeability to gases

• It formed a strong barrier to odors

• It was cheap to produce

What was a significant drawback of the new polyethylene formula compared to PVDC?

• It was harder to manufacture

• It was less effective at trapping odors

• It was more expensive

• It was more toxic

How did the oxygen transmission rate change when switching from PVDC to polyethylene?

• It increased significantly

• It remained the same

• It became negligible

• It decreased significantly