Yes, hemp is often mixed with other materials to improve it. Hemp is a very rough fabric that needs cotton to make it more wearable. A fabric can indeed be made stretchy by mixing it with polyester. There is also a way of weaving yarn into a fabric that can make it stretch but I don't see that very often.
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Amazing
Very informative. I didn't realize the truth of bamboo fabric production
Question: is it true that a garment can't be fully sustainable for its practicality? For example: they need to mix hemp with polyester for a stretch?
Yes, hemp is often mixed with other materials to improve it. Hemp is a very rough fabric that needs cotton to make it more wearable.
A fabric can indeed be made stretchy by mixing it with polyester. There is also a way of weaving yarn into a fabric that can make it stretch but I don't see that very often.