| 摘要 |
PROBLEM TO BE SOLVED: To provide a monomer-cast polyamide elastomer having improved moisture resistance and heat resistance. SOLUTION: This polyamide elastomer molding is obtained by allowing a mixture of (a) 98.5 to 92.5 mol % of cyclic amide and (b) 1.5 to 7.5 mol % of polytetramethylene glycol, polypropylene glycol or their mixture having a number-average molecular weight (Mn) of 1,000-2,000 to react with each other. The molding from the polyamide elastomer prepared has an elastic recovery rate of 80 to 100 %, when the second type dumbbell test specimen according to JIS K6301 is prepared from the polyamide resin and a 10 mm long line is marked on the dumbbell specimen from the center toward both edges and the specimen having the line mark is tested with a tensile tester with one specimen grip distance of 7cm and the other specimen grip is moved to elongate by 20 mm at a speed of 500 mm/min, then immediately the grip is allowed to turn back to the original position. At this time, the distance L (mm) between the marked line is measured in mm and the elastic recovery is calculated according to the formula: [20-(L-20)]20 x 100. COPYRIGHT: (C)2006,JPO&NCIPI |
