| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain the subject composition having a high crosslinking rate and productivity, capable of hot-air crosslinking in a hot-air valcanization tank or the like, and useful in the automotive industry by specifying the properties of the hot-air crosslinked rubber sheet obtained therefrom. SOLUTION: This composition crosslinkable by hot air or hot press is such that a crosslinked rubber sheet obtained by molding this composition into a sheet-like form followed by hot-air crosslinking of the sheet-like form has the following properties: the surface cannot be scratched at all when subjected to a pencil hardness test using a pencil with a hardness rank of HB, and furthermore, a crosslinked rubber sheet obtained by molding this composition into a sheet-like form followed by hot-press crosslinking of the sheet-like form has the following properties: (1) compression set after heat-treated at 150 deg.C for 22 h is <=70%, (2) the rate of volume change after immersed in a DOT-3 brake fluid at 150 deg.C for 70 h is -10 to +50%, (3) tensile strength retention and elongation retention are 50-150% and >=50% after heat-deteriorated at 150 deg.C for 70 h, respectively, and (4) tensile strength as a normal-state physical property is 3-25 Mpa.</p> |
