Which type of cups keep hot water hottest polystyrene plastic glass?

While polystyrene (Styrofoam) cups are often used for hot drinks, they are not the best choice for keeping water hot. Here's why:

* Poor Insulation: Styrofoam's insulating properties are decent but not exceptional. While it will slow down heat loss, it's not the most effective material for keeping water hot for extended periods.

* Heat Transfer: Styrofoam is a relatively poor conductor of heat, meaning it will transfer heat from the hot water to the surrounding air more quickly than some other materials.

* Limited Durability: Styrofoam cups are fragile and prone to cracking or breaking, especially when exposed to hot liquids.

Better Options for Keeping Water Hot:

* Double-walled Stainless Steel Tumblers: These tumblers are highly insulated, often with a vacuum between the walls, which minimizes heat transfer and keeps beverages hot for hours.

* Travel Mugs with Insulation: These mugs often use a combination of materials, such as stainless steel and foam, to create a highly effective thermal barrier.

* Ceramic Mugs: While not as insulated as stainless steel or travel mugs, ceramic mugs retain heat better than polystyrene.

In short, while polystyrene cups are acceptable for short-term hot beverage use, they are not the best choice for keeping water hot for extended periods. Double-walled stainless steel tumblers and travel mugs offer superior insulation and durability.