| 摘要 |
<p>In a process for increasing the molecular weight of a polyamide, e.g., nylon-6,6, comprising heating the polyamide in the presence of a catalyst to effect a desired molecular weight change, the improvement which comprises employing, as the catalyst, (A) R1(CH2)nPO3R2?2 and R1(CH¿2)nPO2HR2, where R1 is 2-pyridyl, NHR4 or NR¿2?4 or NH¿2?, n is an integer of from 2 to 5 inclusive, R?2¿, being the same or different, is H or C¿x?H2x+1, R?4¿, being the same or different, is C¿x?H2x+1, and x is an integer of from 1 to 10 inclusive; and (B) R?3X(CH¿2)n'PO3R2?2 and R3X(CH¿2)n'PO2HR2, where X is S or O, n' is an integer of from 2 to 5 inclusive, R3 is H or C¿x?H2x+1, x is an integer of from 0 to 10 inclusive and R?2¿ is defined as in formula (A).</p> |
