Abstract: Expandable polystyrenic resin particles having superior resistance to cracking of a molded foam product, having superior retention of blowing agent and maintaining expandability over a long period of time, a production process thereof, and a molded foam product are provided.

Abstract: A pre-expanded beads of olefin-modified polystyrene-based resin comprising a pie-expanded beads of a polystyrene-based resin modified with a polyolefin-based resin, wherein a styrene-based monomer forming a polystyrene-based resin in the beads is used in the range of 100 to 1,000 parts by weight relative to 100 parts by weight of a polyolefin-based resin, a bulk density of each bead is 0.012 to 0.20 g/cm3, and an absorbance ratio at 698 cm?1 and 2850 cm?1 (D698/D2850) obtained from an infrared absorption spectrum of each bead surface measured by ATR method infrared spectroscopy is in the range of 0.1 to 2.5.

Abstract: Expandable polystyrenic resin particles having superior resistance to cracking of a molded foam product, having superior retention of blowing agent and maintaining expandability over a long period of time, a production process thereof, and a molded foam product are provided.

Abstract: A pre-expanded beads of olefin-modified polystyrene-based resin comprising a pie-expanded beads of a polystyrene-based resin modified with a polyolefin-based resin, wherein a styrene-based monomer forming a polystyrene-based resin in the beads is used in the range of 100 to 1,000 parts by weight relative to 100 parts by weight of a polyolefin-based resin, a bulk density of each bead is 0.012 to 0.20 g/cm3, and an absorbance ratio at 698 cm?1 and 2850 cm?1 (D698/D2850) obtained from an infrared absorption spectrum of each bead surface measured by ATR method infrared spectroscopy is in the range of 0.1 to 2.5.

Abstract: The present invention provides a process for producing a molded foam article of a crystalline aromatic polyester resin. The process is characterized by heating the surface temperature of a mold for cavity-molding to the temperature within a range of from (td+35) to (Tg+57)°C. (Tg is a glass transition temperature of the crystalline aromatic polyester resin prepuffs), thereby to mold prepuffs, and cooling the surface of the mold to a temperature not lowered than Tg for at least 20 seconds.

Abstract: A foamed styrene resin material has a density .rho. of 0.02 to 0.008 and a melt tension of the styrene resin of 5 to 40 gf. The relation between an average cell diameter d (.mu.m) and the density .rho. is given by the expression: ##EQU1## and a relation between a thermal conductivity .lambda. (kcal/m.multidot.h.multidot..degree. C.) and the density .rho. given by the expression: ##EQU2## Accordingly, the foamed styrene resin material has a low thermal conductivity and excellent insulating property in spite of a low density (high expansion ratio foam) thereof.

Abstract: A foamed article of styrene type resin, in which base resin particles are styrene type resin particles obtainable by a graft polymerization of a cis-rich polybutadiene with a styrene type monomer, a blowing agent contains n-pentane as its main component and the foamed article shows a density of 0.015-0.040 g/cm.sup.3, an average foam diameter of 60-300 micrometers and a closed cell foam rate of not less than 50%.

Abstract: A foamed article of styrene type resin, in which base resin particles are styrene type resin particles obtainable by a graft polymerization of a cis-rich polybutadiene with a styrene type monomer, a blowing agent contains n-pentane as its main component and the foamed article shows a density of 0.015-0.040 g/cm.sup.3, an average foam diameter of 60-300 micrometers and a closed cell foam rate of not less than 50%.