can artificial placental sac material can be used as bag instead of plastic bag
Biodegradable plastic bags are made exactly the same way as conventional plastic bags. The difference is the resin. You have to use biodegradable resin as the raw material.
The biodegradable resin contains an additive like starch. When you put organic matter inside, the bacteria eat up the starch and the plastic disintegrates.
The biodegradable resin granules are used to produce bags on a blown film extruder line. Here the granules melt and come out as as a bubble of thin film (white bubble in the pic below) which is air cooled. The circular bubble then collapses as it passes through nip rollers (top most point) and the collapsed film is wound on a roller( extreme left of the diagram). Please remember that when a circular bubble gets collapsed, you get two layers of film. In the image below, you will see the blown film extrusion process. The steel hoppers are the one from which the resin granules are fed.The roller on which the film is wound is then taken to the finishing department for printing, cutting and making bags by sealing one end of the required size.
The main raw material for the manufacturer of corn starch biocompostables are made from corn starch. The starch can be converted into a polymer, the main ingredient in materials which have a plastic-like feel.
The main ingredient for biodegradable plastic bags is PLA-polylactic acid. It is produced by fermenting crops like maize, cassava, potato, sugarcane etc. For maize starch biodegradable plastic bags, maize starch is converted into polymers which are then bound together to make the bags. They have a similar look and feel like that of a plastic bag, however they can be clear or opaque, and soft or hard.
Discarded plastic bags float all over the place and create litter and blockages that need manual labor to clear. That on top of the non-renewable resources needed to make them. The bag industry was so bent on blocking the ban that they did not present biodegradable bags - the "fighting mind" as we call it in martial arts. They lost, so now they are banned.
As answered before, most “biodegradable” plastic bags are made our of PLA. However, in almost all applications, they are a very bad idea.
Since you don’t want the bag to biodegrade when you are using it, the biodegradability threshold have to be set fairly high (you can formulate PLA so it biodegrades only in certain conditions). This result is a bag that may degrade slowly in large chunk of PLA in “normal” conditions but this doesn’t solve the main problems of regular plastic bags. These bags will only fully degrade in an accelerated composting process (high temperature, controlled amount of aeration and the right balance of nitrate and carbon). The main problem is, almost all plants who perform accelerated composting will refuse them because, even in accelerated composting, they will take much longer than natural materials to degrade, slowing down the entire process.
You could, of course, formulate the PLA to degrade as fast as, say, cotton, except it will then start degrading significantly and loose its mechanical resistance before it reaches the end user.
And last, but not least, almost no one recycle PLA because it is degrading at the molecular level.
Because the word “biodegradable” sells, people are still making and selling them although they are the worst type of bags: Not really biodegradable in fact, not recyclable, and less reusable than regular plastic bag. When you need biodegradable bags (for example for compostable materials), paper bags are a much better solution and they can be made very resistance. For any other use, regular plastic bags or reusable bags are a much better solution.
I just hope you will not start manufacturing more of these.
organic/animal or human membrane artificially made???
