The invention history and evolution of plastic bags

A photographer's darkroom experiments led to the creation of the original plastic. Alexander Parks had many hobbies, photography being one of them. In the 19th century, people were not able to buy ready-made photographic film and chemicals like they are today, and had to often make what they needed themselves. So every photographer must also be a chemist.

One of the materials used in photography is "collodion", which is a solution of "cellulose nitrate", a solution of cellulose nitrate in alcohol and ether. It was used to adhere light-sensitive chemicals to glass to create the equivalent of today's photographic film.

In the 1850s, Parks examined different methods of processing collodion. One day, he tried mixing collodion with camphor. To his surprise, the mixture produced a hard material that was bendable. Parks called the substance "paxine," and it was the earliest plastic.

Parks used "Paxin" to create a variety of items: combs, pens, buttons and jewelry-printed jewelry. However, Parks had little business sense and lost money on his business ventures. Above: In the 20th century, people began to discover new uses for plastics. Almost everything in the home can be made from some form of plastic.

It was left to other inventors to continue to develop and profit from Parks's work. John Wesley Hyatt, a printer from New York, saw the opportunity in 1868, when a company that made billiard balls complained about a shortage of ivory. Hayat improved the manufacturing process and gave "Paxin" a new name - "Celluloid" (fake ivory - translator's annotation). He found a ready market from billiard ball manufacturers and was soon making a variety of products out of plastic.

Early plastics caught fire easily, which limited the scope of products made from it. The first plastic that could successfully withstand high temperatures was "Bakerite" (ie, phenol-coated plastic - translator's annotation). Leo Backlund received the patent in 1909.

In 1909, Baekeland in the United States synthesized phenolic plastic for the first time. In the 1930s, nylon was introduced again. It was said to be "a fiber synthesized from coal, air and water, thinner than spider silk, harder than steel, and better than silk." Their emergence laid the foundation for the invention and production of various plastics thereafter. Due to the development of the petrochemical industry during World War II, petroleum replaced coal as the raw material for plastics, and the plastics manufacturing industry also developed rapidly.

Plastic is a very light substance that can be softened by heating at a very low temperature and can be made into various shapes as desired. Plastic products are brightly colored, light in weight, not afraid of falling, economical and durable. Its advent not only brings a lot of convenience to people's lives, but also greatly promotes the development of industry.

However, the invention of plastics was less than 100 years ago. If people were ecstatic about their birth at that time, now they have to deal with these plastics that have filled our lives and brought great harm to the human living environment. Threatening things and painstakingly.

Plastic is a chemical petroleum product extracted from petroleum or coal. Once produced, it is difficult to degrade naturally. Plastics will not decay and degrade even if they remain underground for 200 years. A large amount of plastic waste buried underground will destroy the permeability of the soil, cause the soil to harden, and affect the growth of plants. If domestic animals accidentally eat plastic mixed into feed or left in the wild, they can also die due to digestive tract obstruction.

At present, China's annual plastic output is 3 million tons, and its consumption is more than 6 million tons. The annual plastic production in the world is 100 million tons. If calculated based on 15% of the annual plastic waste, the world's annual plastic waste is 15 million tons. China's annual plastic waste is more than 1 million tons. The proportion of discarded plastics in the garbage The proportion accounts for 4O%. Such a large amount of waste plastics are buried underground as garbage, which will undoubtedly bring greater pressure to the already scarce arable land.

Plastics not only bring convenience to people’s lives, but also bring troubles to the environment that are difficult to deal with. People call the disaster caused by plastics to the environment "oil pollution".

Currently, many countries adopt methods of incineration (thermal energy regeneration) or reprocessing and manufacturing (product regeneration) to recycle waste plastics and achieve the purpose of saving resources. When waste plastics are burned or reprocessed, they will produce gases that are harmful to the human body and pollute the environment. Therefore, it can be said that the disposal of waste plastics is still a major headache in environmental protection work.