At present, the total output of plastics in the world has exceeded 100 million tons / year, and the plastics used for packaging account for more than 30% of the whole plastic market. According to statistics, plastic waste accounts for about 30% of the total volume of garbage and 10% of the total weight of garbage. The difficult degradation of plastic waste has become an important aspect of municipal solid waste. Although incineration can recover energy, air pollution caused by improper incineration is worrying.
Environmental problems of disposable plastic packaging materials non recyclable and reusable disposable plastic packaging mainly refers to polystyrene (PS) and other packaging materials, which are a major factor causing environmental pollution. Disposable plastic packaging materials are unsustainable consumer products. The so-called sustainable consumer materials are not only biodegradable, but also save resources and energy, easy to recycle and cheap.
Petroleum is the raw material of plastic products, while petroleum is a non renewable disposable natural resource. If the precious limited petroleum resources are used on disposable packaging products, it is a great waste of resources. The global crude oil will be exhausted in 50 years. Therefore, uncontrolled production and use of disposable packaging plastics will cause global energy problems.
Natural degradable pulp molding
At present, there are two ways to solve the problem of disposable plastic packaging in China, which are paper packaging and degradable plastic packaging. Paper packaging can be divided into pure fiber board and pulp molding packaging materials which meet FDA standards; and degradable plastic packaging can be divided into three basic categories: photodegradation, biodegradation and starch degradation, each of which has its advantages and disadvantages.
Degradable plastic packaging material the degradable problem of plastics is one of the important research topics in many countries. At present, degradable plastics can be divided into two types: completely degradable and partially degradable. Fully biodegradable plastics use bioengineering methods, such as bacterial fermentation, gene recombination, and chemical synthesis, to produce completely biodegradable plastics. For example, PLA, PCL, PHB, bionol, etc.
At present, these products can not enter the commercial market because of the high price. The structure of the degradable plastics can be changed by using the photolysis agent, such as the photo degradable part of the plastic and the degradable part of the plastic. The plastic mixed with starch, in which the starch can be biodegraded under the action of biology or microorganism, so as to make the plastic disintegrate. Although the degradable plastics can achieve the purpose of partial degradation, there are still some problems such as consumption of petroleum resources, immature processing technology and unstable product quality.
Paper packaging paper products come from the grass cellulose of trees, especially the raw materials of pulp molded products are waste paper and annual herbaceous plants. The raw materials are rich and cheap. After the products are used, the wastes are easy to decompose and do not damage the environment. Moreover, the raw material sources are formed by waste recycling, which can not only reduce the consumption of paper resources, but also obtain pulp production on the basis of paper materials In the process, a lot of energy consumption is saved to meet the requirements of resource and environment protection. For plastic products, pulp molded products are comparable in portability, practicality and hygiene. Natural degradable pulp molding