Plastic is promoted as recyclable, as a way to save the world from rising temperatures caused by carbon dioxide. Plastic recycling fails. There are still newspapers promoting plastic by publishing articles that are just advertisements for expensive brands.
Plastic fibres replace cotton. Traditional cotton growing requires masses of water and fertiliser. Australia is a dry continent, mostly desert, and developed cotton growing techniques using far less water. If you want to compare the environmental impact of cotton to plastic, you have to differentiate between traditional cotton growing and modern efficient farming.
Cotton captures carbon from the atmosphere then returns the carbon to the atmosphere when the cotton is dumped or burned. Plastic is made from exogenous carbon, carbon mined from the earth as coal, oil, and unnatural gas. When plastic is dumped and burned, the carbon pollutes our atmosphere.
Recycling plastic sounds good. You can also recycle cotton. Old cotton clothes are cut up as cleaning rags, something you cannot do with plastic clothes.
Recycling is too expensive
Most plastic is dumped because it is too expensive to sort and separate. You cannot mix plastics in recycling. Plastic clothes are too difficult to recycle. Recycling is really only for plastic bottles. Most plastic recycling produces a lower grade plastic that cannot be recycled again. Australia exported the plastic rubbish to China and now China has banned the import of the plastic trash. Australia and most Western countries are back to dump or burn.
Burning plastic can generate electricity but it is still CO2 pollution. Burning cotton generates electricity and recycles the carbon captured by the cotton plant, making cotton the better choice.
Plastic in a dump will produce carbon dioxide for up to a hundred years. The plastic you buy today will continue to pollute the lives of your children, grand children, and great grand children.
Hemp is an alternative to plastic and cotton. You can grow hemp as a food source. Hemp seed is a good source of Omega-3 and protein. Hemp cloth is rough compared to cotton and works better as outer clothing than anything in contact with your skin. Heavy processing can render hemp to a similar softness as cotton. Regular processing makes hemp more like cheap linen.
Linen was the major cloth a few hundred years ago. Linen is produced from flax. Flax is difficult to grow and process, compared to cotton and hemp. Linen is not a food source, another reason to use hemp.
Ramie is a fibre produced in a similar way to linen but using a plant growing in Asia. Ramie is a natural alternative for areas too warm to produce linen, areas where hemp may be the better crop.
Bamboo is now processed into fine cloth and paper. The processing is not yet evaluated for sustainability with most of the online "information" pages produced people who make money from bamboo. The bamboo, or any other plant material, has the cellulose extracted and converted into viscose. A more efficient and less wasteful source of cellulose is the wheat stalks left over from harvesting wheat. Viscose should be produced from the plant waste left over from food production.
Bamboo makes sense only in a few places where bamboo grows as a weed or as a source of building materials. The offcuts from building materials can then be processed to viscose.
Rayon is a brand name of viscose. Viscose can be produced from any plant material with an easy to process cellulose content. Most viscose processing uses a polluting process. The cellulose is converted into a plastic then extruded into fibre, the same as any other plastic. The pollution is the worst part of the process.
There are alternative cellulose processing methods including the one used for lyocell, sold under the brand name Tencel. The lyocell production uses a narrow range of hardwoods and some chemicals that are recycled. Lyocell has almost no pollution. The source wood can be from sustainable tree farms. The source wood can be chipped from the offcuts left over from timber milling.
Instead of burning the wood offcuts to produce steam to run the timber mill, you use solar panels to power the machines and process the offcuts into lyocell. you would have to check the individual suppliers to see how well they stick to the ideal.
Polyester is a popular plastic in clothing. Polyester is a typical plastic, horrible against your skin. A small percentage is added to some cotton clothing without spoiling the feel of cotton. Cheap "cotton/polyester" blends are mostly polyester with only a token amount of cotton added to let the brand misrepresent the product. Polyester does have the advantage of blocking the sun better than other fibres and is the main component of swimwear with a high sun protection factor.
Polyester can be recycled. There are people recycling PET bottles as polyester cloth. There are some clothing manufacturers offering to take back old polyester clothes for recycling. There are no local recyclers. Australia would be a good place to recycle swimwear, board shorts, and SPF factor shirts because so many Australians swim and work outdoors.
Without an active clothing recycling program, polyester is a bad choice.
PET is polyester for bottles. PET cannot be recycled to new bottles because PET absorbs chemicals. In the rare cases where you see PET drink bottles made from "recycled" material, they are made from offcuts from regular bottle production, not from recycled material.
PET from clear plastic bottles can be recycled as polyester fibre and as plastic board for various uses. The results cannot be easily recycled again, giving PET just two uses. PET bottles can also be reused as drink bottles and for some other uses, giving PET bottles a change to have more than two lives.
PET recycling requires massive subsidies to work in western countries. India has the highest rate of PET recycling, 90%, due to cheap labour. Some European countries reach 50%. In Australia, PET recycling is subsidised by a 10 cent deposit scheme and still has only a low recycling rate.
Nylon has many uses and most of them include additives that make recycling of nylon impossible. When nylon is recycled, it is from a well known pure source. An Italian carpet fibre manufacturer recycles only pure nylon carpets made from their fibre and the result is far more expensive than fresh nylon, to the point where only a few expensive fashion brands can afford the nylon.
PET to polyester is currently more economical and better for clothing. Recycling nylon and similar plastics tend to produce coarse bulk plastics for fillers. In Australia, back when we manufactured cars, the car manufacturers bragged about recycling plastic from cars. They actually recycled only offcuts and some dashboards from almost new cars. The plastic was recycled only as rubbish bins because it was useless for anything else.
Steel and glass are easy to recycle. We have local steel and glass recycling. Choosing real steel components, instead of plastic, means products like cars and dishwashers, will last twice as long then be 99% recycled.
As an example, our dishwasher is a cr*p brand already installed when we purchased our home. The plastic parts fell apart after only two years of very light use. Our previous dishwasher, a good brand, lasted more than twenty years because a few interior components were stainless steel instead of plastic.
When you recycle something like a dishwasher, the device is separated into major components. The copper is separated form the iron/steel. Both are melted in furnaces where the plastic is burnt off. 100% of the copper and steel then go into new products.
The plastic components in your dishwasher might be marked for recycling but there is no way to recycle them. In India, where labour is really cheap, the dishwasher might be stripped down to smaller pieces with some plastic recycled. Everywhere else, it is burnt.
Choose natural materials. Choose glass, steel. If you must use plastic, buy reusable items. Outside of India, the PET to polyester recycling is the only real success.