Polylactide (PLA) fiber/Yarn has good characters below:

• can be used for knitting and non-woven fabric and degradable. 
• made by natural corn starch or plant fiber through fermentation and polymerization. It is 100% biodegradation material as well as recyclable polyester made from renewable feedstock. Lactic acid as the raw material is produced by fermentation of glucose or sucrose and is refined to a high purity.
• safety and health fibre and environment friendly, it is the best substitute for traditional wood and plastic products.
• do good to human; lactic acid one component in human body, without allergenicity/sensitisation to people
• good ability to absorb & release sweat than polyester
• fire-retardant naturally, and with very low smoke when burning