Critical review of the molecular topology of semicrystalline polymers: The origin and assessment of intercrystalline tie molecules and chain entanglements

• Published in: Journal of polymer science. Part B, Polymer physics Vol. 43; no. 14; pp. 1729 - 1748
• Main Author: Seguela, Roland
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15.07.2005; Wiley
• Subjects: Applied sciences; chain entanglements; crystallization; Exact sciences and technology; mechanical properties; Organic polymers; Physicochemistry of polymers; polyethylene (PE); Properties and characterization; semicrystalline polymers; slow crack growth; Structure, morphology and analysis; tie molecules; slow crack growth; State of the art; polyethylene (PE); Semicrystalline polymer; semicrystalline polymers; mechanical properties; Topological structure; chain entanglements; Melt crystallization; tie molecules; crystallization; Molecular entanglement; Formation mechanism
• ISSN: 0887-6266; 1099-0488
• DOI: 10.1002/polb.20414

Intercrystalline molecular connections in semicrystalline polymers have been the subject of numerous discussions and controversies. Nevertheless, there is one point of agreement: such intercrystalline tie molecules have a prime role in the mechanical and use properties of the materials, notably the resistance to slow crack growth. This article is a critical review of the mechanisms of generation of the tie molecules during the stage of crystallization and of the experimental and theoretical assessment of their concentration. Polyethylene and related materials are mainly studied. The contribution of chain entanglements is also discussed in parallel with tie molecules. Particular attention is paid to Huang and Brown's statistical approach, which appears to be the most appropriate one for predictive purposes and has aroused much interest from various authors. Attempts are made to provide solutions to the shortcomings of this model. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1729–1748, 2005