Vacuum bottle or plastic stopper?
The stopper is good because the stopper is inflated not only after being immersed in water, but also to achieve better sealing effect. It also has a loose texture and good heat insulation (the voids reduce the heat radiation, convection and conduction). Plastic plug if the inside is empty, the inside of the air convection heat easily; if the interior is not empty, it is easy to conduction heat dissipation, and plastic smell. A short period of time does not usually affect your health, because plastic used in food or cutlery is processed.
If the quality of the bottle is qualified, the water poured out will not be poisonous. Because that kind of plastics should be tested before they are put into use. Not all plastics are poisonous, even under high temperature conditions.
Cork is better, because the cork after water immersion can expand, better sealing effect, plastic if not food grade, the best can not be used for a long time, the body has certain side effects. And it smells a little plastic.
