Process for preparing a high-molecular polyamide, polyester, copolyester, copolyamide or polyester-amide block copolymer

• Main Authors: LOONTJENS, JACOBUS ANTONIUS, PLUM, BARTHOLOMEUS JOHANNES MARGRETHA
• Format: Patent
• Language: Chinese; English
• Published: 16.09.2003
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

The invention relates to a process for preparing a high-molecular polyamide or polyester or copolyester by melt-mixing polyamide or polyester or copolyester having a lower molecular weight with a blocked diisocyanate having the following formula. Wherein R= linear, branched or cyclo aliphatic C2-C20 or aromatic C6-C20 and B1, B2 = Caprolactam, Imidazole, dimethyl-pyrazole, triazole, oxim, malonic acid ester, ethylacetylacetonate, phenol, cresol, aliphatic alcohol, secundary amine, hydroxy benzoic acid methyl ester. With the process according to the invention a permanent increase in the molecular weight of a polyamide is obtained within 2 minutes, whereas this takes at least 10 minutes under comparable conditions using a blocked isocyanate according to the state of the art.