摘要:
A multi-layer expansion-molded article of a polypropylene resin, which is obtained by molding a multi-layer parison comprising a foamed resin layer and a resin layer provided on the outer side of the foamed resin layer in a mold in such manner that at least part of the opposed inner surfaces of foamed resin layer in the parison are fusion-bonded to each other, and has a polypropylene resin layer on the surface of a foamed polypropylene resin layer, wherein a melt tension, MTfr (gf) and a melt flow rate, MFRfr (g/10 min) obtained by measurement to a polypropylene resin forming the foamed resin layer in the expansion-molded article satisfy the relationship [log MTfr>−0.74 log MFRfr+0.66], and a melt tension, MTur (gf) and a melt flow rate, MFRur (g/10 min) obtained by measurement to a polypropylene resin forming the resin layer on the surface of the foamed resin layer satisfy the relationship [log MTur>−1.02 log MFRur+0.47].
摘要:
In the present invention, for the production of a blow-molded foam, there is used a base resin which is mainly composed of a polypropylene resin and has, at 230° C., a melt tension (MT) of 10 gf or over and a melt flow rate (MFR) of 0.5 g/10 minutes or over. A foaming agent is added to the base resin, followed by melt kneading by means of an extruder under high temperature and high pressure conditions to provide a foamable melt. This melt is subjected to extrusion from a circular die 5 and expanded to form a cylindrical foamed parison 4. Thereafter, molds 6, 6 are clamped, and the parison 4 in a softened condition is placed in the molds 6, 6, and a pressurized gas is blown into the parison 4 from a gas blowing port 7 for blow molding in the form of a hollow shape conforming to the mold profile to produce a blow-molded foam.
摘要:
Prevention of damage of wooden construction materials of a building by termites by laying one or more panels each having a polycarbonate resin foam layer on the ground on which the building is constructed or by arranging such panels on surfaces of continuous footing of the building or of vertical concrete walls of the building. The concrete wall may be formed using modular concrete form structure units each having a pair of opposing side panels, with each side panel having a polycarbonate foam layer.
摘要:
A polycarbonate resin-containing composition is extruded through a die together with a blowing agent to produce a foamed body. The composition has a storage modulus G'.sub.A dyn/cm.sup.2 at a temperature of 250.degree. C. and an angular frequency of 0.1 rad/sec and a storage modulus G'.sub.B dyn/cm.sup.2 at a temperature of 250.degree. C. and an angular frequency of 10 rad/sec, wherein the storage modulus G'.sub.A and storage modulus G'.sub.B satisfy the following conditions: 0.ltoreq..alpha..ltoreq.2.0 2.20.ltoreq..beta..ltoreq.5.70 where .alpha. represents (logG'.sub.B -logG'.sub.A)/2 and .beta. represents (logG'.sub.B+logG'.sub.A)/2.
摘要:
Description is made of an open cell polystyrene resin foam having a content of organic volatile matters of less than 100 ppm. The open cell foam is suitable as a core material for a sound insulating material or a vacuum heat insulating material.The open cell foam can be produced by melt-kneading a polystyrene resin having a content of organic volatile matters of 100 ppm or higher together with water in an extruder, sucking out the organic volatile matters as an azeotrope with water through a vent, injecting a blowing agent and kneading the injected mixture, and extruding the mixture into a lower pressure area to cause the resin to foam.