| 摘要 |
PURPOSE:To obtain the orientation property of extruding direction and improve the mechanical strength in all directions by a method wherein a precursor, obtained by grafting polyolefin resin with organic silane compound, is extruded under a temperature lower than the melting point thereof. CONSTITUTION:A precurser, consisting of a graft copolymer obtained by grafting polyolefin resin with organic silane compound shown by a general formula RR'SiY2 (wherein R is monovalent olefin series unsaturated hydrocarbon group or hydrocarbon oxy group, Y is hydrolyzable organic functional group and R' is organic silane compound shown by R or Y), is extruded in solid under a temperature lower the melting point thereof. Obtained crosslinking polyolefin tubular molded form is provided with a sectional area smaller than the sectional area orthogonal to the extrusion molding direction of a precursor and with the peripheral length of a section longer than the peripheral length of the section of the same direction of the precurser, therefore, crosslinking degree per unit volume of the molded form may be increased and, especially, the mechanical strength of a wall in the direction of the thickness thereof may be increased whereby the cleavage of the wall in the direction of the thickness thereof may be eliminated completely. |
