Better Touch Better Business
Contact Sales at XINCHUANG BIO.
Degradable materials refer to a class of materials that can meet the requirements of application during use and storage, and can change chemical structure in a short period of time under certain environmental conditions and lose material use performance. Degradable materials are classified into common degradation materials and biodegradable materials. Biodegradable material refers to a degradation material that can be converted into carbon dioxide and water within 180 days by the action of microorganisms under composting conditions. Not all degradation materials are biodegradable materials.
Such as photo-oxidative degradation plastics, which are not real biodegradable plastics, but this photodegradable material is the first to popularize the concept of degradation, probably in the 1960s and 1970s. Photooxidation plastics, which are ordinary petroleum-based plastics, add some additives that can cause the breakage of petroleum-based plastic molecular chains by the action of sunlight, so they can become plastic fragments under the action of light. This degradation has relatively large defects: the first photodegradation does not really achieve degradation, and the second decomposes into plastic fragments, which have a very serious impact on plants and microorganisms, and also produce microplastics.
This type of destructive biodegradable plastic is a natural appearance of natural substances such as starch, wheat flour, rice flour or bamboo fiber, which is added to conventional plastics to achieve so-called biodegradation. Although natural materials can degrade, the rest of the plastic is still plastic. Therefore, such destructive bioplastics are not completely biodegradable plastics. Some people say that it is partially degraded, but partial degradation is the real harm, because the so-called partial degradation refers to the degradation of natural materials, so that the remaining petroleum-based plastics are destroyed, but the recovery value and use value are lost. It gradually ages in nature and becomes plastic. Its hazard is similar to the photodegradable plastics. It causes traditional petroleum-based plastics to become debris and remains in the soil, causing soil compaction, microbial death, soil erosion and so on. This material has a more terrible place because it looks environmentally friendly and even smells environmentally friendly. For example, some starch-based bioplastics smell even starchy, very comfortable, which makes people mistakenly think that this is really environmentally friendly to use, but it is not.
There is a material that is truly biodegradable, called compostable biodegradable materials. the real biodegradable material must be compostable. Those that are degraded by the sun, the sun, and the rain are not really biodegradable materials. By definition, the real degradable material must be a material that is completely converted to carbon dioxide and water within 180 days by microbial action under composting conditions. This 180 days is artificially prescribed. Why do you have to do it for half a year? Because it needs to be processed together with the kitchen waste. It is difficult to handle three hundred days and five hundred days, so people make this rule. In fact, depending on the thickness of the material, the degradation time of compost will be different. If it is a plastic film, it can be completely degraded in 30 or 50 days. If it is made into a relatively thick injection molding product, it may take 180 days or even not enough.
Compostable biodegradable materials fall into two categories, one being bio-based compostable materials and the other being petroleum-based compostable materials. The bio-based compostable material is further divided into materials directly derived from plants, such as pulp, polylactic acid (PLA), aliphatic polyester (PHA), and blends of natural materials with the above two types of polymers. Petroleum-based compostable materials derived from petroleum, such as polybutylene terephthalate (PBAT), polyethylene glycol (PCL) etc.
Compostable biodegradable materials also have drawbacks because they are dependent on composting facilities. The most suitable conditions are 60℃ (40℃ - 80℃ can be), 90% humidity conditions can be quickly degraded. However, in the natural environment, although it can still be completely degraded, it will take at least several years. The degradation time needs to be longer under conditions of low temperature, drought or microbial inactivity.