摘要:
A method for producing polypropylene-based resin expanded beads includes dispersion, blowing agent impregnation, and foaming steps. Beads used in the dispersion step include a core layer having a polypropylene-based resin as a base material resin, and a fusion-bonding layer covering core layer; the beads fusion-bonding layer includes carbon black and a NOR-type hindered amine; a carbon black blending ratio is adjusted to 0.5 wt % or more and 5 wt % or less; and an amine blending ratio of the beads is adjusted to 0.03 wt % or more and 0.5 wt % or less; the polypropylene-based resin expanded beads have a surface on which a fusion-bonding layer is located; the fusion-bonding layer includes the carbon black and hindered amine; a carbon black blending ratio is 0.5 wt % or more and 5 wt % or less; and a blending ratio of the hindered amine is 0.03 wt % or more and 0.5 wt % or less.
摘要:
A polypropylene-based resin expanded beads configured to include an NOR type hindered amine and has a surface on which a thermoplastic polymer layer is located, in which a blending ratio of the amine in the expanded beads is 0.03 wt % or more and 0.5 wt % or less, and a blending ratio of the amine in the thermoplastic polymer layer is less than the blending ratio of the amine in the expanded beads. Further, the method for producing the expanded beads includes a covering and foaming step, in which in the resin beads to be obtained in the covering step, a blending ratio of the amine in the resin beads is adjusted to be 0.03 wt % or more and 0.5 wt % or less, and a blending ratio of the amine in a thermoplastic polymer layer is adjusted to be lower than the blending ratio of the amine in the resin beads.
摘要:
A method for producing cross-linked polyethylene resin expanded beads, including dispersing polyethylene resin particles containing a halogen-containing flame retardant in a dispersing medium in an autoclave, impregnating the dispersed resin particles with an organic peroxide and cross-linking the polyethylene resin therewith at a specific temperature range determined by the melting point of the polyethylene resin and by melting point or glass transition temperature of the flame retardant, impregnating the dispersed resin particles with a blowing agent, and then foaming and expanding the resulting cross-linked polyethylene-based resin particles.