Skin-core structure poly(3-hydroxybutyrate-co-3-hydroxyvalerate)fiber, nonwoven material and preparation methods of skin-core structure poly(3-hydroxybutyrate-co-3-hydroxyvalerate)fibers and nonwoven material

The invention discloses a skin-core structure poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) fiber, a nonwoven material and preparation methods of the skin-core structure poly(3-hydroxybutyrate-co-3-hydroxyvalerate)fiber and the nonwoven material, wherein the core layer of the fiber is PHBV having a 3-hydroxyvalerate (HV) content of 0-20 mol%, the skin layer is PHBV having a HV content of 20-100 mol%, and the melting point of the skin layer is lower than the melting point of the core layer. The skin-core structure PHBV fiber preparation method comprises: drying raw materials, respectively adding to the corresponding material hoppers of a compound spinning machine, carrying out melt transporting, spinning, cooling through cold air blowing, carrying out winding feeding, carrying out oil bath stretching, carrying out steam bath stretching, carrying out tension heat shaping, oiling, carrying out silk stacking, coiling, loosening, and cutting to prepare the skin-core structure PHBV short fiber. The corresponding nonwoven material preparation method comprises: (1) carrying out combing net forming by using the skin-core structure PHBV short fiber as a raw material to prepare a skin-core structure PHBV fiber net; and (2) carrying out thermal adhesion on the skin-core structure PHBV fiber net to obtain the PHBV nonwoven material, wherein the thermal adhesion temperature is between the melting points of the skin layer and the core layer, and the obtained PHBV nonwoven material is mainly used for medical health, and other fields.