摘要 |
<p>An improved process for controlling and reducing the concentration of free carboxyl end groups in condensation polyester melt spun fiber is provided. By selection of a multifunctional compound, it is possible to increase the intrinsic viscosity of the fiber. The process comprises admixing and reacting with molten polyester polymer an effective amount of a lactim compound of formula (I), wherein n is an integer of 2 to 15; m is an integer of 1 to 4; R1 and R2 are independently hydrogen, halogen, nitro, amine, C1-C10 alkyl, C5-C12 cycloalkyl, C7-C9 alkyl aromatic, or C6-C10 aromatic; and R3 is a mono- to tetravalent organic radical selected from the group consisting of C1-C32 alkyl, C5-C14 cycloalkyl, C7-C16 alkyl aromatic, and C6-C14 aromatic. The lactim reacted polymer is then melt spun to form a fiber.</p> |