A social news about Professor Zheng Qiang, Secretary of the Party Committee of Taiyuan University of Technology, made headlines among many people (see picture below). Professor Zheng is definitely a clear stream in the Internet celebrity world, and is known for his sharp views, surprising words, and daring to speak out, and is known as a contemporary Chinese university"Zheng Energy".。In the eyes of students, Professor Zheng has no pretensions, is approachable, and real, and students love to call him"Brother Qiang".。Regarding the rights and wrongs of this turmoil, the law will give a fair judgment.
Actually,Professor Zheng Qiang is also a polymer materials expert and chemist, dedicated to the research of polymer rheology and polymer composite materialsHe has won the Wang Baoren Award for Polymer Basic Research of the Chinese Chemical Society, 4 first prizes of provincial and ministerial science and technology awards (ranked first), and 1 second prize of national teaching achievements (ranked first).
In May last year, at the high-end academic forum of "Chemistry Talks" organized by the Chinese Chemical Society, I listened to Professor Zheng Qiang's online report entitled "The Rights and Wrongs of Plastics and "White Pollution"", and through the "four questions" of plastics, he shared his thoughts on hot topics of social concern such as plastic ban and degradable plastics. Professor Zheng's exposition and views are very objective, gentle and down-to-earth, pointing out a certain direction for the virtuous cycle development of China's plastic materials industry. Although it has been a year and a half, his views have always been deeply remembered. In the morning, after seeing the hot news about Professor Zheng mentioned earlier, I listened to the recording of the speech made at that time again, and sorted out the following article for fans, especially Professor Zheng Qiang's fans. The content has been abridged.
Preamble
In recent years, with the continuous increase of national environmental protection work, especially the continuous enhancement of people's awareness of green environmental protection, the discussion on plastic "white pollution" is increasing, and it is still very intense from time to time. It is reported that some places are discussing and preparing to introduce documents or regulations related to single-use plastic products. To be honest, there is such an unprecedented level of attention to one material material that is probably unmatched by any other kind of material. On the one hand, it shows that the popularization of scientific knowledge among the whole people is increasing day by dayOn the other hand, it also shows how significant and far-reaching the impact of plastics is on human beings today!As a polymer scholar and a university professor engaged in plastics professional education, I feel it is necessary to talk about my superficial understanding and opinions.
Q1: Where does plastic come from?
Materials are the ladder of progress in human society
Materials are the main indicator of the degree of human development
Materials are also the material basis for human survival.
Polymer materials are another milestone in the progress of human society. The use of polymers has a long history, and natural polymers such as leather, hemp, silk, lacquer, paper, and gum are widely used directly or processed in nature. The emergence of synthetic polymers marks a new era in the understanding and application of materials after stone tools, ceramics, cement, copper, iron, aluminum, and steel.
Polymer materials continue to come out.
Polymer materials are divided into three categories: plastics, rubber, and fibers, among which plastics have been most widely used because of their lightweight, plastic, corrosion-resistant, insulation, sound insulation, high specific strength and high specific modulus, low cost, etc., and the global volume output of plastics has reached 26% of the total of steel and cement, and the annual growth rate of global plastic consumption has reached 8%.
The chemical synthesis of commonly used plastics is actually "carbon capture" and "carbon sequestration", which is the contribution to the "double carbon" work. Plastics are one of the lowest carbon emitters in the entire industrial materials sector, behind aluminum and paper.
Second question: What is plastic used for?
As of 2015, 8.3 billion tons of plastic were produced, and about 6.3 billion tons (editor's note: 9.2 billion tons as of 2022) became waste. The annual output of plastic products in the world reaches 3800 million tons, of which 2 are waste plastics200 million tons. Single-use plastic products account for 40% and are concentrated in the packaging industry. China's output of plastic products is about 80 million tons per year, of which 60 million tons are waste plastics.
Plastic is everywhere in life, and people in today's society cannot live without plastic, and they can't live without plastic. Without plastic mulch, agriculture cannot be called modern agricultureWithout plastic wrap, the world's food waste would increase by 30%. 
Three questions: what's wrong with plastic?
The main culprit of white pollution lies in plastics" and "banning the use of disposable non-degradable plastic products" is correct and scientific, and there must be a big question mark. The "white pollution" of plastics is related to the "light" and "thin" characteristics of plastics, and it is also related to people's behavioral norms and social morality!It is the improper handling of plastic that causes white pollution, and the light weight and low price of plastic is the original sin that it is not taken seriously when it is processed, so it is easy to be regarded as a disposable product. In contrast, tires are more harmful to human beings because they are not moldable and cannot be used, and there are about 1 billion waste tires in the world every year, but have we ever heard of "black pollution"?The reason is that the tire industry has achieved standardized processing of tires, and tires are heavier and more expensive, so they are more popular with humans. Similarly, the annual production of global construction waste is 3 billion tons, have you ever heard of "gray pollution"?!This is also due to the processing of the specification. 
Objectively speaking, if it is not used as a cheap and high-quality disposable product, especially if it is not discarded at will after use, and can be truly strictly classified**, then the stigma of "white pollution" will not be deducted from the head of disposable plastic products.
Four questions: what is enough for degradation?
"Degradation", in layman's terms, is the process of "reverse polymerization", which is the process of synthesizing polymers and dissociating their structures. In addition to what is commonly referred to as degradation, the chemical cycle is also a controlled degradation.
The vast majority of widely used plastic products do not require degradation, do not need to be degraded, and even require that they cannot be degraded within the service life. The main targets that need to be degraded are "single-use plastic products". From a professional point of view, the statement "prohibiting the use of non-degradable disposable plastic products" is accurate and scientific;It is unprofessional, wrong and needs to be corrected to arbitrarily rephrase it as "prohibiting the use of disposable non-degradable plastic products";Any mention of "banning plastics" is not only inconsistent with the trend of scientific progress in human materials, but also easily misleads the public and has a serious impact on social development and people's lives.
In the face of limited earth resources, based on the concept of environmental green protection and sustainable use of resources, it is necessary to think: except for special purposes and use occasions, any materials and products, including plastics, are "one-time use" scientific?Is it in line with the concept of green and sustainable development?"Multiple use" and "long-term use", should it be more advocated and pursued?
Based on reality, if we want to gradually implement the "ban on the use of non-degradable disposable plastic products", it seems that it is more necessary to vigorously promote the change of plastic use methods, reduce and limit the production and use of "disposable plastic products", and advocate "multiple use" and "long-term use". This initiative will have a linear or even exponential positive correlation effect on the reduction of plastic product discard, which is a scientific concept and strategy for achieving a greener and more environmentally friendly sustainable application of plastics. From the perspective of molecular design to engineering technology in materials science, if plastics can achieve "initiated degradation" and "controlled degradation" after multiple or long-term use, it should become an ideal goal to pursue and achieve.
It should be emphasized that in order to meet people's daily life and special needs, trying to use non-petroleum-based, especially bio-based raw materials for the preparation of degradable (easily degradable) disposable plastic products, is a new field of interest in plastics academia and industry, and has made a positive contribution to seeking to solve the so-called "white pollution". However, any waste items (materials) after use, if they cannot be disposed of in an orderly manner, will become pollution, either "white pollution" or "gray pollution" or "black pollution". Therefore, even degradable plastics, if they do not attach great importance to orderly** and treatment, they still have the possibility of becoming "white pollution". 
Two points in particular:The first is to exaggerate and exaggerate the importance of the degradable plastics (plastic degradation) industry, shift the focus of plastic research and industry to the field of degradable plastics, and blindly follow the trend of the project, which will have an impact on the research and development of high-performance multi-functional plastics in China, especially the research and development of high-end plastic special materials that solve a number of stuck necks, and will mislead the development of China's plastics industrySecond, the purpose of the production and development of non-petroleum-based and bio-based raw materials is limited to the preparation and production of degradable disposable plastic products, which is short-sighted and lacks foresight. The use of non-petroleum-based and bio-based raw materials for the preparation of high-performance non-disposable plastic products is a new field with important scientific value and broad market prospects.
Looking to the future of plastics
Relevant policies should be strictly and orderly handled, using the terms of "multiple use" and "long-term use" to achieve the grand goal of "triggering degradation" and achieving "controllable degradation", and solving the research and development of several high-end plastic special materials that are stuck in the neck.
"Banning plastics" is not advisable"Plastic limit" is necessary"Degradation" is non-mythical,The presentation needs to be clearExecution needs to be coordinated!Editor's note:
Zheng Qiang may be regarded as an Internet celebrity professor, but his heart is hot, let us praise the Internet celebrity principal secretary!