| 摘要 |
Molded articles of polymerized lactams are prepared by pumping of a catalyst containing partial lactam melt at a temperature of +/-1 DEG C. of a temperature in the range of 160 DEG C. to 170 DEG C. and a lower temperature activator containing partial lactam melt at a temperature of +/-1 DEG C. of a temperature in the range of 160 DEG C. to 170 DEG C. to which activator addition is delayed relative to catalyst addition, with separate gear pumps to a mixing zone maintained between 170 DEG and 175 DEG C., the pumps connected to the mixing zone by straight feed tubes positioned at an angle of inclination to the horizontal of a maximum of 10 DEG , each feed tube having a volume of at least one-third greater than the pump to which it is connected and form the mixing zone into a mold. At least part of the gases released are returned to the mixing zone by the tube systems and gear pumps. The products formed crumble on being heated to a temperature of approximately 220 DEG C. to 280 DEG C. and are free of bubble formations and shrink holes. Apparatus to carry out the method is also provided.
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