What Does A Degradable Shopping Bag Mean?

What does a degradable shopping bag mean?

  Degradable plastics refer to plastics that add a certain amount of additives (such as starch, modified starch or other celluloses, photosensitizers, biodegradants, etc.) during the production process, and have reduced stability and are more easily degraded in the natural environment.

  Tests have shown that most of the degradable plastics begin to thin, lose weight, and decrease in strength after being exposed to the general environment for 3 months, and gradually crack into pieces. If these fragments are buried in waste or soil, the degradation effect is not obvious.

Degradable shopping bags can be classified into photodegradable plastics, biodegradable plastics, chemically degradable plastics, and composite degradable plastics according to the environmental conditions that cause degradation.

Photodegradation refers to the plastic that decomposes by absorbing sunlight and causing a photochemical reaction. Photodegradable plastic refers to a type of plastic material that degrades and splits when exposed to sunlight or exposed to other strong light sources, thereby losing its mechanical strength and then decomposing. As long as the structure or group that can promote photodegradation is added to the polymer material, it can become a photodegradable plastic. There are two methods for preparing a photodegradable plastic: a copolymerization method and an additive method.

The copolymerization method is a plastic made by introducing appropriate photo-sensitive groups such as carbonyl groups, double-strands, etc. into a comonomer of a macromolecular structure, such as ethylene-carbon monoxide copolymer developed by DuPont company Brubaker et al., and vinyl ketone developed by Gullet, Canada. The base-ethylene polymer controls the photolysis rate of the polymer by adjusting the concentration of carbon monoxide and carbon, which is essentially the copolymerization and modification of ethylene, which requires complicated equipment and more severe technical conditions. It is difficult to implement this process in the short-term in China. .

The additive method adds a photosensitizer, such as benzophenone, to the polymer material, absorbs ultraviolet light in the presence of light and deprives the polymer of hydrogen to generate free hydrogen, which promotes the oxidation of the polymer material to achieve the purpose of degradation.

Photodegradable plastics are formed by introducing weak bonds or chromophores into their polymers or by adding photosensitizers to common plastics. Therefore, photochemical reactions take place under light irradiation, causing plastics to become brittle and break, and then become smaller and smaller. Fragments.

Photosensitizers undergo photochemical reactions in polymers, generating free radicals and achieving controlled photodegradation. The alkyl thiocarbamate type photosensitizers developed by Professor G. Scott of Ston University in the United Kingdom have been industrialized, and stearate and ferrocene derivatives have also been used. At present, there are more domestic research and development.

The disadvantage of photodegradable plastics is the need for light irradiation. When buried in soil or covered by plants, they cannot be degraded or the degradation rate is too slow. Even if the degraded fragments cannot continue to pulverize, the pollution problem cannot be completely solved.

Meco Bags Co., Ltd

Add:No. 8, Jinxing Road (M.), Qianku Town, Cangnan County, Wenzhou City, Zhejiang Province, China