the inner wall of the paper cup is coated, and consumers are worried about hidden dangers.
Disposable paper cups are very familiar to everyone. They are small in size and easy to carry. They can be used by one person and thrown away after use, which is especially convenient. However, a recently reprinted Weibo on the Internet said that the inner wall of the disposable paper cup is coated with a layer of wax. We also know that the wax will melt when it meets high temperature. Does that mean that the disposable paper cup can’t hold hot water? Will drinking the hot water contained in the disposable paper cup affect people’s health? Let’s take a look at the investigation by the reporter of CCTV finance and economics first time.
A recent online microblog said that the inner wall of a disposable paper cup is coated with a layer of wax. When the water is more than 40 degrees Celsius, the wax on the inner wall of the cup will melt into the water and be eaten into the body. Immediately, “whether the disposable paper cup can hold hot water” caused heated discussion. The reporter walked into several department stores as a consumer. The salesperson’s answers to the question of whether the paper cups sold in the stores can hold hot water are very consistent: where can we use hot water if we can’t. As for the online saying that there is a layer of wax on the inner wall of the paper cup that “melts when it is hot”, the salesperson gave a negative answer.
Subsequently, the reporter bought four kinds of paper cups with different prices and sizes at random from these stores and took them to the Chemistry Laboratory of Hefei University of technology. Bei Lei, a graduate student in the Department of chemical technology of Hefei University of technology, said that the first experiment he would do was to see if the paper cups purchased by the reporter had the “waxed inner wall” described on the Internet. The experimental results show that it is rare to use wax as the inner wall coating of disposable paper cups sold in the market. But then he did a second experiment, adding hot water of 100 degrees Celsius to four cups of different materials to observe whether the cups were soft. After five minutes, the shape of these cups changed. This indicates that the material of the inner wall of the cup may have undergone a chemical reaction.
the coating will soften in case of heat. It is better not to hold hot water in disposable paper cups.
From the experimental results, we can also see that the material of the inner wall of the cup may react chemically when it contacts hot water. What is the material? As for the inner wall material of these disposable paper cups used in the experiment, professionals said that this is the common “polyethylene” in our life. Even if the coating of paper cups is not the wax transmitted online, such paper cups are not suitable for holding hot water. Liu Kun, a doctor from the school of chemical engineering of Hefei University of technology, said that the melting point of polyethylene materials is about 110 degrees to 120 degrees, which means that when we use water with high temperature, it may lead to the oxidation of polyethylene plastics. Therefore, if you use a paper cup with a polyethylene inner wall to drink hot water, there will be certain safety hazards. However, on the outer package of the paper cups purchased by the reporter, most of them said that they could withstand high temperatures of more than 100 degrees, and some even said that they could microwave 130 degrees. In this regard, Liu Kun, a doctor from the school of chemical engineering of Hefei University of technology, said that because the temperature rises, when it approaches the melting point of polyethylene or polypropylene, these materials will soften. After softening, they may enter the human body through drinks. Of course, this is a small amount. Only if they are drunk for a long time, can they cause safety hazards and hidden dangers to the human body.
Professionals remind that compared with paper cups with polyethylene inner walls, paper cups made of “polypropylene” materials are safer. When consumers buy paper cups, they should not only pay attention to the materials selected, but also see whether there are detailed manufacturer, shelf life and inspection marks on the outer package. It is better not to use paper cups to hold hot water.
Leave a Reply