Seaweed Fiber Fabricated with Agar Alkali-Free Extracted from Gracilaria lemaneiformis

The sulfate groups in agar structure played a good role in the formation of fiber. However, commercially available agar is usually extracted from red algae by alkali treatment to decrease the content of sulfate group for the purpose of high gel strength. In this paper, an alkali-free method of agar extraction from Gracilaria lemaneiformis was proposed for the wet-spinning purpose. This method is environmentally friendly, reduces the extraction steps, saves energy, and reduces the production cost of agar fiber. The improved agar preparation process not only has higher agar yield, but also has higher molecular weight and sulfate group content, which is beneficial to the preparation and forming of fiber and makes the fiber have higher mechanical strength and elongation. Therefore, this extraction technology has broad application prospect in the textile field.