Biodegradable plastics in my country are mainly used in agriculture, food packaging, degradable foam nets and disposable snack boxes. Agricultural plastic film Agricultural film belongs to the three pillars of agricultural production (chemical fertilizers, pesticides, agricultural film), which was originally controlled by the state and has been in short supply in the market.
In the field of agricultural film, the traditional plastic film is mostly made of PE, which is difficult to degrade under natural conditions and can remain in the soil for 100 to 200 years. The continuous increase in the amount of residual film in the cultivated soil will deteriorate the soil environment and reduce the soil water content. , hardening and decreased fertility. Biodegradable mulch has the same function as ordinary agricultural mulch, but its effect on heat preservation, moisture retention and yield is stronger than ordinary mulch. my country is the world's largest mulching country. The domestic mulching film covers an area of 300 million mu, with a coverage rate of 36%. The annual consumption of agricultural film is about 2.5 million tons.
There are two ways to degrade biodegradable plastic bags, which can be divided into:
(1) Biophysical degradation method: When microorganisms attack and erode polymer materials, the polymer components are hydrolyzed, ionized or protonated due to the growth of biological cells and split into oligomer fragments, and the molecular structure of the polymer remains unchanged. is the biophysical action of the polymer degradation process that occurs.
(2) Biochemical degradation method: Due to the direct action of microorganisms or enzymes, polymers are decomposed or oxidatively degraded into small molecules until they are finally decomposed into carbon dioxide and water. This degradation method belongs to biochemical degradation.
Stone paper is also a natural degradable material, which can be converted into calcium carbonate in a few months under the light, which reduces a lot of pollution compared with non-degradable plastic long-lived land. In agriculture, stone paper can be used to make mulch, pesticide bottles, compost bags, water-retaining materials, etc., to increase green and safe food for agricultural development.
