The proposal to ban single-use plastics comes as part of the European Plastics Strategy. On March 27, 2019, the European Parliament voted overwhelmingly to approve the ban, agreeing to ban single-use plastic products on a large scale from 2021 to control plastic waste pollution. On January 19, 2020, the National Development and Reform Commission and the Ministry of Ecology and Environment jointly issued the "Opinions on Further Strengthening the Control of Plastic Pollution". Therefore, people in the industry often call this "Opinion" a new version of the plastic restriction order. The biggest difference between the new version of the plastic restriction order and the previous one is that for the first time, the specific requirements and established goals for prohibiting and restricting plastic products are clearly put forward, and the category of plastic products is officially regarded as the main body of prohibition and restriction. Various plastic products have put forward detailed requirements. From the three levels of different regions, different industries and different varieties, the production, sales and use of plastic products have been delineated in more detail. It is called the "plastic ban". In addition to China, including the European Union, New Zealand, the United States, Africa, etc., have issued a "plastic ban" in light of their own national conditions. This will have a certain impact on the composite flexible packaging industry in the future. Therefore, the promulgation of the "plastic ban" may force the green upgrade in the field of composite flexible packaging. This article attempts to analyze this.
1. Common composite flexible packaging materials and their processes
At present, composite flexible packaging is one of the common packaging forms used in my country's food industry. In supermarkets, most of the dazzling variety of foods are displayed in the form of composite flexible packaging. Flexible packaging has played an extremely important role in all aspects of people's lives. Compared with traditional packaging materials such as ceramics, glass, etc., the lightness of plastic flexible packaging is unmatched by other materials; in terms of performance, composite flexible packaging has specific barrier properties, moisture resistance, and processing formability, which cannot be replaced by other materials. . In the late 1970s, my country introduced composite flexible packaging from Japan. After years of practice and innovation, my country's composite flexible packaging has developed from small to many, from nothing, from single to diversified. Until today, my country has become a big country in composite flexible packaging. .
Based on the different requirements for packaging materials of various types of food or medicines, generally speaking, the requirements for packaging materials of food or medicine packaging are: non-toxic, no peculiar smell, no pollution to the contents, good air tightness, heat sealing resistance, moisture resistance, UV resistance, heat resistance, etc.
Based on the above performance requirements, for composite flexible packaging, the common ones are: paper/plastic composite, plastic/plastic composite, aluminum/plastic composite. The substrate of composite flexible packaging has two layers, three layers, four layers or more. In practical applications, according to the combination of different plastic films, it can be adjusted into a variety of composite flexible packaging structural materials in the form of composites to achieve flexible packaging applications in different market segments. Such as cpp/pe, ny/pe, bopp/pvd/pe and so on. At present, in the above applications, the types of substrates that can be used in composite flexible packaging generally include pe, pp, pet, cpp, bopp, ny, pvdc, etc.
For the application of food, the composite flexible packaging actually belongs to the category of disposable packaging. After the user opens the composite flexible packaging and enjoys the food, the composite flexible packaging is discarded. At present, the domestic plastic ban order has not yet involved composite flexible packaging, but the plastic ban order from abroad has subdivision requirements for most of the plastics involved. Therefore, in the future, the flexible packaging materials produced by Chinese composite flexible packaging enterprises will be When it is circulated internationally by food or drug companies, it is inseparable from the requirements of the international plastic ban. Based on this, when considering the requirements of plastic ban orders, composite flexible packaging materials companies should consider the relevant requirements and impacts of foreign plastic ban orders, and should reserve the degradation technology of composite flexible packaging in advance for emergency.
2. Degradation technology path of composite flexible packaging materials
At present, pe, pp, pet, cpp, bopp, ny, pvdc, etc. are generally involved in composite flexible packaging. The promulgation of the ban on plastics makes the development and innovation of biodegradable plastics a hot spot.
At present, it is difficult for most fully biodegradable plastics to have the barrier properties, air tightness and high temperature processability required for composite flexible packaging.
At present, degradable plastics are mainly divided into three categories: photo-oxidative degradation plastics, biodegradable plastics, and anaerobic microbial degradation technology, which are mainly used in the packaging industry, compostable, and anaerobic digestion environments. Therefore, combined with the actual application, performance requirements, processing environment and storage of composite flexible packaging materials, from the perspective of cost and ease of use, it is recommended that composite flexible packaging enterprises adopt anaerobic microbial degradation technology and integrate with the original composite flexible packaging material technology system of flexible packaging companies. , to embrace biodegradation faster and meet the requirements of the "plastic ban".
The AdmPro® Anaerobic Microbial Degradation Masterbatch of Luoyang Lvzhihui Plastic Degradation Technology Co., Ltd. is an organic additive made from traditional plastic injected with anaerobic organic auxiliaries, which introduce plastics into organisms through chemical activities caused by bacteria In the degradation stage, only natural gas and bioenergy are left in the end. The addition of AdmPro® anaerobic microbial degradable masterbatch enables plastic to biodegrade in landfills through anaerobic digestion, supporting marine degradation.
AdmPro® Anaerobic Microbial Masterbatches introduce plastics into an anaerobic environment for microbial degradation through a series of chemical and biological processes (a process called bioassimilation). Allows microbes to create a biofilm structure to penetrate plastic. The biofilm forms only in the absence of oxygen/anaerobic conditions, i.e. in landfills and deep sea environments; while helping to expand the molecular structure, creating more space for microbes and emitting chemicals on the polymer chain that attract other microbes Signal to eat plastic, increasing the rate of microbial degradation.
Anaerobic microbial degradation in nature happens all the time, because the process is a relatively slow process, so it is not easy to detect, however, solid organic PE (or PP, pet, pvc, etc.) with the addition of AdmPro® anaerobic microbial degradation masterbatch Plastic can greatly speed up the process, it allows PE (or PP, pet, pvc, etc.) plastic to complete the biodegradation process at a higher rate. Let plastic produce only carbon dioxide, biogas (methane) and humus (organic matter), the same biological processes and residues as organic matter. Its degradation realization process includes the following:
Aerobic Phase – During this phase, enzymes and decomposing chemicals act as catalysts for the biofilm covering the PE (or PP, pet, pvc, etc.) plastic. During this time, aerobic microorganisms are gradually formed, and the moisture in the garbage keeps accumulating. Standard PE (or PP, pet, pvc, etc.) plastics have relatively little hygroscopic capacity, but AdmPro® anaerobic microbial degradation masterbatches can cause further swelling that weakens polymer bonds. This creates molecular space for microbial growth, which begins the process of aerobic degradation, during which oxygen is converted to carbon dioxide.
Anaerobic, non-methanation stage – After the oxygen concentration has been sufficiently reduced, the anaerobic process begins. During the initial stage (hydrolysis), microbial colonies engulf the particles and reduce macromolecular polymers to simpler monomers through an enzymatic process. The AdmPro® anaerobic microbial degradation masterbatch results in additional swelling and opening of the PE (or PP, pet, pvc, etc.) polymer chains and increased quorum sensing. This further motivates the microorganisms to increase their colonization and consumption of polymer chains. Over time, acid generation occurs in which simple monomers are converted into fatty acids. During this phase, the production of carbon dioxide occurs rapidly.
Anaerobic, Methanogenic Unsteady - Microbial colonies continue to grow, engulfing PE (or PP, pet, pvc, etc.) polymer chains and creating increasingly larger molecular spaces. At this stage, the production of acetic acid occurs, converting fatty acids into acetic acid, carbon dioxide and hydrogen. As this process continues, the CO2 rate drops and hydrogen production eventually stops.
Anaerobic, steady state stage of methanogenesis – The final stage of decomposition involves methanogenesis. Acetate is converted to methane and carbon dioxide, and hydrogen is consumed, as the microbial colony continues to devour the remaining surface of the PE (or PP, pet, pvc, etc.) polymer. This process continues until the remaining elements are humus. This highly nutrient-rich soil creates and improves the environment for microorganisms and enhances the final stages of decomposition.
In terms of the upgrading of composite flexible packaging degradation technology, AdmPro® anaerobic microbial degradation masterbatch can be added to the raw materials of PE (or PP, pet, pvc, etc.) and other films to achieve microbial degradation without changing the equipment and process of the original plastic products , is a more reliable degradation and upgrading technology in the current green composite flexible packaging.
Figure 1 below takes PE as an example. AdmPro® anaerobic microbial degradation masterbatch is added in the production process of PE film. After testing by the internationally renowned testing agency - Intertek Group, its 45-day biodegradation rate is 7.15%, which does not affect the performance of PE. performance, without changing equipment and processes.
