Foamable chlorinated vinyl chloride-based resin particles, foamed particles thereof, chlorinated vinyl chloride-based resin foam molded article, and method for producing foamable chlorinated vinyl chloride resin particles
Expandable chlorinated vinyl chloride-based resin particles from which a chlorinated vinyl chloride-based resin foamed molded product achieving both high expansion ratio and excellent surface appearance are provided. The expandable chlorinated vinyl chloride-based resin particles have a porosity of not more than 5.5 (ml/100 g).
1 . Expandable chlorinated vinyl chloride-based resin particles having a porosity of not more than 5.5 ml/100 g.
2 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , wherein a maximum expansion ratio times/volatile component content % by weight at expansion is not less than 2.2.
3 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , comprising a chlorinated vinyl chloride-based resin having a chlorine content of not less than 60% by weight and not more than 75% by weight.
4 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , comprising a physical blowing agent.
5 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , comprising at least one saturated hydrocarbon having 4 to 6 carbon atoms.
6 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , comprising ketone.
7 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , comprising a chlorinated vinyl chloride-based resin having an average polymerization degree of not less than 300 and not more than 3000.
8 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , comprising at least one saturated hydrocarbon having 4 to 6 carbon atoms, wherein the at least one saturated hydrocarbon having 4 to 6 carbon atoms is pentane.
9 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , comprising a blowing agent in an amount of 1% by weight to 40% by weight, with respect to 100% by weight of the expandable chlorinated vinyl chloride-based resin particles.
10 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , comprising a copolymer having an aromatic vinyl monomer and an unsaturated nitrile as structural units and/or an acrylic-based resin.
11 . The expandable chlorinated vinyl chloride-based resin particles according to claim 1 , comprising chlorinated polyethylene.
12 . A method for producing expandable chlorinated vinyl chloride-based resin particles, the method comprising the step of:
extruding a blowing agent-containing chlorinated vinyl chloride-based resin melt, which has been obtained by melting and kneading with an extruder, through a die having a plurality of holes into pressurized water,
immediately after the extruding, cutting the extruded blowing agent-containing chlorinated vinyl chloride-based resin melt into particles with a rotary cutter while cooling the extruded blowing agent-containing chlorinated vinyl chloride-based resin melt to solidify, wherein a resin temperature of the blowing agent-containing chlorinated vinyl chloride-based resin melt at a tip of the extruder is 130° C. to 250° C.
13 . A method for producing expandable chlorinated vinyl chloride-based resin particles, the method comprising the step of:
extruding a blowing agent-containing chlorinated vinyl chloride-based resin melt, which has been obtained by melting and kneading with an extruder, through a die having a plurality of holes into pressurized water,
immediately after the extruding, cutting the extruded blowing agent-containing chlorinated vinyl chloride-based resin melt into particles with a rotary cutter while cooling the extruded blowing agent-containing chlorinated vinyl chloride-based resin melt to solidify, wherein a pressure at a tip of the extruder is 4 MPa to 20 MPa.
14 . Expandable chlorinated vinyl chloride-based resin particles obtained by the method for producing the expandable chlorinated vinyl chloride-based resin particles according to claim 12 .
15 . Expandable chlorinated vinyl chloride-based resin particles obtained by the method for producing the expandable chlorinated vinyl chloride-based resin particles according to claim 13 .