Effect of a tie layer on the delamination toughness of polypropylene and polyamide-66 microlayers

✍ Scribed by T. Ebeling; S. Norek; A. Hasan; A. Hiltner; E. Baer

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 412 KB
• Volume: 71
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19990228)71:9<1461::aid-app11>3.0.co;2-0

✦ Synopsis

The effect of a thin tie layer on the adhesion of polypropylene (PP) and polyamide-66 (PA) was studied by delamination of microlayers. The microlayers consisted of many alternating layers of PP and PA separated by a thin layer of a maleated PP. The peel toughness and delamination failure mode were determined using the T-peel test. Without a tie layer, there was no adhesion between PP and PA. A tie layer with 0.2% MA provided some adhesion; however, delamination occurred by interfacial failure. Increasing the maleic anhydride (MA) content of the tie layer increased the interfacial toughness. With 0.5% MA, the interfacial toughness exceeded the craze condition of PP, and a transition from interfacial delamination to craze delamination occurred. Crazing ahead of the crack tip effectively reduced the stress concentration at the interface and dramatically increased the delamination toughness.