#bioplastics

Leaf-inspired design makes bioplastics degradable, stronger

Society has long struggled with petroleum-derived plastic pollution, and awareness of microplastics' detrimental effects on food and water supplies adds further pressure. In response, researchers have been developing biodegradable versions of traditional plastics, or "bioplastics." However, current bioplastics face challenges as well: Current versions are not as strong as petrochemical-based plastics and they only degrade through a high-temperature composting system. Enter researchers at Washington University in St. Louis, who have solved both problems with inspiration from the humble leaf. Long before plastic, humans wrapped their food in leaves, which easily biodegrade due to an underlying structure of cellulose-rich cell walls. WashU's chemical engineers decided to introduce cellulose nanofibers to the design of bioplastics.

Researchers are using bacteria that eat food scraps to create a new kind of fully biodegradable plastic that reduces waste and could be less expensive to manufacture than current plastics are. The team from the University of Waterloo says this new method produces plastics that are soft and flexible, leading to many potential applications such as food wrap, drug delivery and in the repair of damaged tissues and organs. The study, "Production and Characterization of Biopolymer from Food Waste Using Pseudomonas putida," was recently published in ACS ES&T Engineering.

Most recently (like, today) corn starch/glycerine/vinegar bioplastics (+yellow onion skin dye for the orange, not yet set fully) Should be good to take out of the plates in like 8 or so days

WIP drying pumpkin out to hopefully make a patterned container, found a pumpkin someone had thrown on the sode of the road and carved a design into it/emptied it out

i'm *hoping* packing it with salt will let it drain of enough water like the last pumpkin i made this way. I think i might not have thinned the walls enough and it'll take a while to dry before i can test this guess

Spun yarn (raw wool washed using saponins extracted from lambsquarters/goosefoot seed coatings)

SPIDER SILK plus beginnings of a very tiny weaving attempt again with them; i think it's too tiny for the warp though

A small sampling of plant pigments (usually anthocyanins) i've tried working with recently (mostly mixed with water, some egg tempura experimenting as well)

Hoping that posting this will kickstart my brain to post more about these specific things with even more detailed observations soon

From the article; Enormous islands of it float in our oceans and microscopic particles of it are in our bodies. The durability, malleability and low cost of plastics has made them ubiquitous, from packaging to clothing to aircraft parts. But plastics have a downside. Plastics contaminate nature, are tough to recycle and their production emits more CO2 than all air traffic combined.

Now, researchers at the University of Copenhagen’s Department of Plant and Environmental Sciences have invented a new material made from modified starch that can completely decompose in nature – and do so within only two months. The material is made using natural plant material from crops and could be used for food packaging, among many other things.

"We have an enormous problem with our plastic waste that recycling seems incapable of solving. Therefore, we’ve developed a new type of bioplastic that is stronger and can better withstand water than current bioplastics. At the same time, our material is one hundred percent biodegradable and can be converted into compost by microorganisms if it ends up somewhere other than a bin," says Professor Andreas Blennow of the Department of Plant and Environmental Sciences.

Only about nine percent of plastic is recycled globally, with the rest being either incinerated or winding up in nature or dumped into enormous plastic landfills.

Bioplastics already exist, but the name is misleading says Professor Blennow. While today’s bioplastics are made of bio-derived materials, only a limited part of them is actually degradable, and only under special conditions in industrial composting plants.

"I don't find the name suitable because the most common types of bioplastics don't break down that easily if tossed into nature. The process can take many years and some of it continues to pollute as microplastic. Specialized facilities are needed to break down bioplastics. And even then, a very limited part of them can be recycled, with the rest ending up as waste," says the researcher.

Starch from barley and sugar industry waste

The new material is a so-called biocomposite and composed of several different substances that decompose naturally. Its main ingredients, amylose and cellulose, are common across the plant kingdom. Amylose is extracted from many crops including corn, potatoes, wheat and barley.

Together with researchers from Aarhus University, the research team founded a spinoff company in which they developed a barley variety that produces pure amylose in its kernels. This new variety is important because pure amylose is far less likely to turn into a paste when it interacts with water compared to regular starch. Cellulose is a carbohydrate found in all plants and we know it from cotton and linen fibers, as well as from wood and paper products. The cellulose used by the researchers is a so-called nanocellulose made from local sugar industry waste. And these nanocellulose fibers, which are one thousand times smaller than the fibers of linen and cotton, are what contribute to the material’s mechanical strength.

"Amylose and cellulose form long, strong molecular chains. Combining them has allowed us to create a durable, flexible material that has the potential to be used for shopping bags and the packaging of goods that we now wrap in plastic," says Andreas Blennow.

The new biomaterial is produced by either dissolving the raw materials in water and mixing them together or by heating them under pressure. By doing so, small 'pellets' or chips are created that can then be processed and compressed into a desired form.

Thus far, the researchers have only produced prototypes in the laboratory. But according to Professor Blennow, getting production started in Denmark and many other places in the world would be relatively easy.

"The entire production chain of amylose-rich starch already exists. Indeed, millions of tons of pure potato and corn starch are produced every year and used by the food industry and elsewhere. Therefore, easy access to the majority of our ingredients is guaranteed for the large-scale production of this material," he says.

Could reduce plastic problem

Andreas Blennow and his fellow researchers are now processing a patent application that, once it has been approved, could pave the way for production of the new biocomposite material. Because, despite the huge sums of money being devoted to sorting and recycling our plastic, the researcher does not believe that it will really be a success. Doing so should be seen as a transitional technology until we bid fossil-based plastics a final farewell.

"Recycling plastic efficiently is anything but straightforward. Different things in plastics must be separated from each other and there are major differences between plastic types, meaning that the process must be done in a safe way so that no contaminants end up in the recycled plastic. At the same time, countries and consumers must sort their plastic. This is a massive task that I don’t see us succeeding at. Instead, we should rethink things in terms of utilizing new materials that perform like plastic, but don’t pollute the planet," says Blennow.

The researcher is already collaborating with two Danish packaging companies to develop prototypes for food packaging, among other things. He envisions many other uses for the material as well, such as for the interior trims of cars by the automotive industry. Though it is difficult to say when this biofriendly barley-based plastic will reach the shelves, the researcher predicts that the new material may become a reality in the foreseeable future.

Biodegradable Plastic made from Tequila Agave Waste

Tequila is one of Mexico’s most iconic and successful exports. According to the Tequila Regulatory Council, for each liter of tequila produced, twelve liters of organic waste is discarded.

Ana Laborde, a businesswoman from Mexico, discovered the wasteful practices behind tequila production – she thought that producing bioplastic bags could be a successful and sustainable business opportunity.

Ana began researching biodegradable alternatives to the ubiquitous plastic bag. However, she grew concerned that many of the common sources of bioplastics, such as corn and potatoes, might better be used as food. Mentioning this to her cousin, who worked in the tequila industry, Ana learned about the vast amounts of unused agave leaves – approximately 400,000 tons each year – created during the liquor’s production. If plant fibers could be easily extracted from agave leaves, she reasoned, this unwanted by-product might be an untapped source of bioplastic.

Her objective was to develop a process to extract cellulose, the molecule that gives plants their structural integrity, from agave leaves. The extracted cellulose could then be used to make biodegradable plastic bags, containers and cleaning supplies. With technical assistance from Mexico’s Center for the Investigation of Applied Chemistry, the team successfully developed this process.

Ana persevered, and in the years since BioSolutions has established strong links with plastic injection molding companies and manufacturers of homeware and promotional materials. BioSolutions’ flexibility has allowed it to expand its product line and customers over time. In 2019, it announced a collaboration with the Jose Cuervo tequila brand to for bars, restaurants and events across Mexico and the United States. BioSolutions is also producing bioplastic beer glasses for concert arenas and stadiums using waste from beer production, an opportunity which required Ana’s team to alter the manufacturing process.