The status and role of plastics in the development of human civilizationThe new field of chemistry research in the 20th century provided new ways and ideas for the development and enrichment of man-made substances. Looking back on the development history of polymer science, it is not difficult to see that there is a new polymer material every 5-10 years, and a new polymer industry is born every 10-20 years, which fully reflects the powerful Vitality and vitality. Polymer materials are undoubtedly a successful example in the development of chemical science and a landmark milestone in the development of material science. The emergence of polymer materials has changed the tradition of human society’s material life for millions of years. It has been based on the tradition of natural gifts, and realized the combination and manufacture of artificial materials with different structures and different properties according to human will and needs; the emergence of polymer materials It changed the material civilization of the 20th century and promoted the progress of human society. Today, polymer materials (synthetic resin, synthetic rubber, synthetic fiber), together with steel, cement, and wood, constitute the four basic materials of modern civilized society, and have become information, energy, industry, agriculture, transportation, and even aerospace and marine development. Materials that are indispensable in all important fields of the national economy penetrate into all aspects of human life. Below we will talk about the status and role of plastics in the development of human civilization and society.
1. Application of plastics in agriculture
China is a developing agricultural country and a country with relatively poor water and land resources. On China’s 9.6 million square kilometers of land, the arable land area is only 10%, which is 1/2 of the world’s per capita arable land area; China is also a water-poor country, and its per capita water resources are only 1/ 1 of the world’s per capita level. 4. It is listed as one of the 13 poorest countries in the world. In the past 30 years, with the great attention and support of the Chinese government, facility agriculture and water-saving irrigation have been on the rise, and water and soil resources have been reasonably protected and utilized, of which plastic has played a vital role. Shed film, mulch film, shading net, insect net, turnover box, tray, nursery equipment, silage film, etc. used in facility agriculture, geomembrane, water pipeline (low pressure, medium pressure water pipeline) used in water saving irrigation Irrigation pipes and drip irrigation pipes are made of polyethylene, polypropylene, polyvinyl chloride, EVA and other materials. The use of agricultural plastics shortens the growth cycle of crops, improves crop yields and land utilization, and saves water and soil resources, and is of particular importance for ensuring food security in China.
Second, the application of plastics in the field of construction
The area of newly-built residential buildings in China's cities and towns was from 92 million square meters in 1980, 170 million square meters in 1990, 549 million square meters in 2000, and 821 million square meters in 2009. In the past 30 years, the growth rate has exceeded 8 times, and the area of newly built houses in China accounts for 50% of the world's total. China's forest area accounts for only 4.6% of the world. The per capita forest area is less than 1/4 of the world average, ranking 134th in the world, but the current excessive logging of wood is still quite serious. In order to alleviate the contradiction of the urgent need of wood, in the large-scale development process of the construction field, the contribution of plastics is indispensable. In doors and windows, due to the use of PVC doors and windows, its air tightness, water tightness, sound insulation, heat insulation, weather resistance, corrosion resistance, stiffness, decoration, use and maintenance are better than ordinary steel and aluminum alloy doors and windows , Energy saving 30% ~ 50%, the current annual market demand for plastic doors and windows in China is 1.5 million tons. Plastic profiles have the advantages of light weight, corrosion resistance, pressure resistance, weather resistance, good water flow, easy processing and installation, and long service life. As China continues to accelerate the pace of modern city construction, it has strengthened the treatment of sewage resources. In the system, building heating, water supply, and gas supply system, the domestic plastic pipe market demand is increasing at a rate of more than 12% per year. In 2010, China's plastic pipe production reached 4.5 million tons. By 2015, it will reach 6 million tons, and my country will become the country with the largest amount of plastic pipes in the world. It can be seen that the weight of plastics in the national economic construction.
Three, the application of plastics in the automotive field
China's automobile industry is an important pillar industry of the national economy. Due to its low consumption and high efficiency in the processing of plastics, plastics can be recycled and reused after use, which has become a process of "reduction, reuse, and recycling" in automobiles. Medium resource-saving and environmentally friendly materials. Automotive plastics cover PP, PVC, ABS, PA, PC, PE, etc. The largest variety of PP is growing at a rate of 2.2% to 2.8% per year. The use of plastics to make automotive parts instead of metal and alloy materials can not only make The car design is more user-friendly and diversified, which improves safety, comfort, and viewing, and is convenient for assembly and maintenance. More importantly, it can reduce the weight of the car, reduce fuel consumption and hydrocarbon emissions. Every time a car loses 125kg of weight, it can run an extra kilometer per liter of fuel. Automobile weight is reduced by 1%, fuel economy can be reduced by 1%, and automobile moving parts are reduced by 1%, fuel economy can be saved by 2%. Internationally, the amount of plastic used for automobiles has become an important indicator of a country’s automobile development level. At present, the amount of plastic used in European high-end cars reaches 150-250 kg/vehicle, although the amount of plastic used for national brand cars only reaches 80-100 kg/vehicle , But it is growing at a very alarming rate. According to the US average fuel economy (CAFE) assessment: for every 10% reduction in vehicle weight, fuel consumption can be reduced by 6% to 8%. Plastic is gradually becoming the best material for automotive lightweight.
Four, the application of plastics in medical and food packaging
In 2009, China's consumption of pharmaceutical and plastic products was 13.5 billion yuan. The specific consumption ratio was 22% of low-density polyethylene, 20% of polyvinyl chloride, 20% of polystyrene, 12% of high-density polyethylene, and 10% of polypropylene. People can use ultra-high molecular weight polyethylene to make artificial hip joints, bone nails, etc.; use PTFE to make artificial hearts, lungs, blood vessels, cardiac membranes, various organs and artificial skin, etc.; use polyethylene, poly Propylene, non-toxic PVC, etc. are used to make syringes, blood transfusion bags, etc.; ABS can be used to make shells for surgical tools and diagnostic instruments.
The amount of plastic used for food packaging accounts for 25% of the total output of plastics. Among them, PET and PEN bottles are mainly used for beverage packaging, and oriented polypropylene films and polyvinylidene chloride films are mainly used for food packaging. There are also polystyrene foam lunch boxes that will be lifted on May 1, 2013.
Speaking of the application of plastic is really beautiful. But as we all know, the use of plastic is a double-edged sword, which can benefit mankind and consume resources. For plastics, currently using petroleum as the main raw material, and also researching and developing production processes using natural gas and coal as raw materials, but from a global perspective, the available development period of oil, natural gas and coal is only 40 years. 60 years and 225 years, therefore, plastics should be used where they are most needed, using their strengths, avoiding weaknesses, making full use of things, and recycling. We advocate a conservation-minded society and let plastic, a great scientific invention, continue to benefit society and future generations.