The theme of this year's World Environment Day is 'Final battle', calling for global attention to one-time plastic pollution. Faced with this global challenge, researchers from various countries are calling for raising awareness of environmental protection among citizens while also trying to use technical means to reduce pollution. Instead of a batch of ''consume a batch'' convert a batch'' of the technical route.
Cellulose replacement
Researchers at Pennsylvania State University have developed a cheap, biodegradable biomaterial that can be used to replace plastic coatings commonly used in packaging.
According to the researchers, the material is derived from cellulose pulp in wood or cotton and chitosan obtained from the exoskeleton of arthropods and crustaceans. These two kinds of biomaterials can be combined in a very firm and durable manner, resulting in coatings The material is both waterproof and oil-resistant and is expected to be used as a substitute for the United States' one million tons of food packaging plastics.
Researchers at the University of Bath in the United Kingdom also focused on cellulose. They used cellulose in waste paper to make pellets less than 0.5 mm in diameter to replace plastic microspheres, which are widely used in detergents and cosmetics, but Difficult to filter and recycle into the ocean, causing pollution.
According to reports, this cellulose-made microbeads are stable in detergents and can be rapidly degraded without polluting the environment.
Eat 'eat' plastic
Plastics have a huge amount of consumption. It is difficult to solve all the problems by replacing alone. Therefore, trying to degrade plastics is also an important research direction for technology.
Japanese scientists have previously discovered a bacterium that can produce enzymes that degrade the main raw material of plastic products, polyethylene terephthalate (PET). On this basis, the U.S. Department of Energy’s National Renewable Energy Laboratory And the team at the University of Portsmouth in the UK discovered another unexpectedly more powerful enzyme that degrades plastics. Researchers hope to use this method to 'digest' more plastic products.
The same idea also inspired researchers at the University of Cambridge in the United Kingdom and their Spanish counterparts. They found that an insect called 'Big Wax' could feed on common polyethylene plastic. Experiments showed that about 100 'big waxes' The larvae were placed in a plastic bag in an ordinary supermarket for 12 hours and the plastic bag was eaten for 92 milligrams.
Researchers plan to use this discovery to find new ways to solve the problem of plastic waste.
Conversion and reuse
The transformation and utilization are another idea to deal with plastic garbage, and related technologies are also continuously advancing.
Researchers from the Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences and the University of California, Irvine, USA, stated that they have made breakthroughs in the degradation of polyethylene waste plastics. The newly developed cross-alkane metathesis catalytic strategy can reduce the reaction temperature of conventional degradation methods, and the degradation products are also It can be used to produce clean diesel. According to a study by the American Chemical Society, researchers used coconut oil and microwaves to recover plastics such as polycarbonate and polyurethane from automobiles for the production of insulating foams, which are stable at high temperatures. Can be used as insulation material in the construction industry.
In the application of plastic degradation technology to commercial practices, two Chinese girls from Canada, Wang Yuwen and Yao Jiayun, have taken a firm step. They have established a technology company focused on plastic recycling in California, USA. The innovative technologies used by the company are available. In 3 hours, the conversion of plastic bags into other plastic products can achieve a transformation rate of 70%. Wang Yuwen said that plastics flow into the sea or landfill is its worst destination. Her dream is to make plastics a brand new jacket. Shirts and running shoes.