Abstract: This method for producing a fiber-reinforced composite material includes: a fiber dispersion process of providing a fiber-dispersed resin by kneading a resin 10a with fibers 10b to disperse the fibers 10b in the resin 10a; and a molecular weight reduction process in which, while transporting the fiber-dispersed resin along an outer peripheral surface of a screw body 37 provided with a passage 88 inside, the fiber-dispersed resin passes from an inlet 91 of the passage 88 to an outlet 92 of the passage 88 and a shear force is applied to the fiber-dispersed resin by restricting the transport of the fiber-dispersed resin with a barrier unit 82 disposed between the inlet 91 and the outlet 92 of the passage 88 on the outer peripheral surface.

Abstract: A production device for melt-blown non-woven fabric, with which a high molecular weight polymer can be reduced in molecular weight by applying a shear force to the high molecular weight polymer without adding an additive such as a peroxide that promotes thermal decomposition reaction, and a low molecular weight polymer can be efficiently produced. The low molecular weight polymer and the melt-blown non-woven fabric are produced using a continuous high shearing device that applies a shear force to the high molecular weight polymer serving as a raw material by rotation of a screw body 37 to reduce the molecular weight of the high molecular weight polymer so as to obtain a low molecular weight polymer, and cools the low molecular weight polymer by passing the low molecular weight polymer through a passage 88 arranged in the axial direction inside the screw body 37.

Abstract: A production method for a low molecular weight polymer suitable for a melt-blown non-woven fabric and a production device for melt-blown non-woven fabric, with which a high molecular weight polymer can be reduced in molecular weight by applying a shear force to the high molecular weight polymer without adding an additive. The low molecular weight polymer and the melt-blown non-woven fabric are produced using a continuous high shearing device that applies a shear force to the high molecular weight polymer serving as a raw material by rotation of a screw body to reduce the molecular weight of the high molecular weight polymer so as to obtain a low molecular weight polymer, and cools the low molecular weight polymer by passing the low molecular weight polymer through a passage arranged in the axial direction inside the screw body.

Abstract: A production method for a low molecular weight polymer suitable for a melt-blown non-woven fabric and a production device for melt-blown non-woven fabric, with which a high molecular weight polymer can be reduced in molecular weight by applying a shear force to the high molecular weight polymer without adding an additive. The low molecular weight polymer and the melt-blown non-woven fabric are produced using a continuous high shearing device that applies a shear force to the high molecular weight polymer serving as a raw material by rotation of a screw body to reduce the molecular weight of the high molecular weight polymer so as to obtain a low molecular weight polymer, and cools the low molecular weight polymer by passing the low molecular weight polymer through a passage arranged in the axial direction inside the screw body.