- Nov 16, 2017 -
Concept: Biodegradable material refers to the material to add some to promote the degradation of additives, or synthesis of its own degradation of the material, or the use of renewable natural materials made of materials, use and preservation of the period to meet the original application Performance requirements, but after use under specific environmental conditions, so that it can be a short period of time chemical structure changes significantly, which led to some loss of a class of materials.
Category: At present, according to the objective conditions causing degradation or mechanism, degradation materials can be divided into: biodegradable materials, photodegradable materials, oxidative degradation materials. Hydrolysis degradation materials. Environmental degradation materials and destructive biodegradable materials. They can be combined with each other into a better performance degradation materials, such as: light / biodegradable materials.
Photodegradable material Photodegradable material refers to the material under the action of light degradation. Examples of Photodegradable Materials Photodegradable materials can be classified into synthetic degradable materials and additive degradable materials according to the manufacturing method. (1) Synthetic Degradable Material a Photo-degradation of ethylene / carbon monoxide copolymer (E / CO) is characterized by a main chain fracture. The rate and degree of photodegradation of E / CO is related to the amount of ketone groups contained in the chain. The higher the content, the faster the degradation rate and the greater the degree of degradation. Texas scientists have conducted outdoor exposure experiments on E / CO, which eroded in as little as a few days in a sunny June.
b, vinyl / vinyl ketone copolymer (Ecolyte)
Ketones on the side chains of Ecolyte molecules can decompose under natural light. Ecolyte has better photodegradation than E / CO, but at a higher cost. The company is located in:
The disadvantage of these polymers is that once the light begins to degrade, there is almost no induction period, the need to add antioxidants in order to achieve the purpose of regulating the induction period. (2) add type photodegradable material
Addition of photodegradable material is added to the polymer a small amount of photosensitizer, at a low concentration of photo-oxidative degradation catalyst, the reaction of sunlight (ultraviolet light) irradiation, the polyolefin polymer rupture. The company is located in:
In PE, PP and other polymers to add ketones, amines and other photosensitizers can achieve better photodegradability. The company is located in:
The characteristics of this type of polymer: added light-degradable materials, low cost, simple production process, to do a good job of covering the use of plastic film. However, its degradation characteristics of the exposure surface degradation more thoroughly buried in the soil part of the degradation is poor. Degradation of such photodegradation material induction period can be controlled in more than two months. However, the controllability of degradation time is poor. The company is located in:
Oxidative degradation materials: A class of materials that cause degradation by oxidation;
Hydrolytic Degradable Materials: A class of materials that cause degradation by hydrolysis; Environmental degradation materials: A class of materials that are exposed to environmental conditions such as light, heat, water, oxygen, contaminants, microbes, insects, and wind, sand, rain, etc. Mechanical and other joint degradation of materials, degradation of materials is the general term. Destructive biodegradable materials: destructive biodegradable materials currently include starch modified (or filled) polyethylene PE, polypropylene PP, PVC PVC, polystyrene PS and so on. Development: Degradable packaging materials research and use in rapid development, with the energy prices and environmental issues have become increasingly prominent, the world's degradation of alternative materials to traditional petroleum products showed a gradual pace of development, the government is also expected to The introduction of the corresponding preferential policies and laws and regulations to encourage market applications, degradation of materials, large-scale application prospects.