Influence of Cross-Linking Density on the Glass Transition and Structure of Chemically Cross-Linked PVA: A Molecular Dynamics Study

✍ Scribed by Javier Sacristan Bermejo; Carmen Mijangos Ugarte

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 661 KB
• Volume: 18
• Category: Article
• ISSN: 1022-1344
• DOI: 10.1002/mats.200900032

✦ Synopsis

Abstract

Mechanical properties and glass transitions of cross‐linked polymer networks depend strongly on both the network topology and cross‐linking density. A model is developed using a dynamic cross‐linking approach based on a cutoff distance criterion followed by a high‐temperature annealing procedure. The analysis focused on on the influence of cross‐linking degree on chain packing and hydrogen‐bond structure and on the roles played by various energy components in the glass transition process. T~g~ was calculated using two different methods; (i) from the intersection of lines drawn through points in a plot of specific volume versus temperature and (ii) from plots of different molecular energy components as a function of temperature.

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