Effect of isocyanate content on thermal and （异氰酸酯含量对热的影响）.pdfVIP

Polymer 54 (2013) 3079e3085 Contents lists available at SciVerse ScienceDirect Polymer journal homepage: www.elsevi /locate/polymer Effect of isocyanate content on thermal and mechanical properties of polyurea K. Holzworth a, *, Z. Jia a, A.V. Amirkhizi a, J. Qiao b, S. Nemat-Nasser a a Center of Excellence for Advanced Materials, Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA 92093-0416, USA b School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China a r t i c l e i n f o a b s t r a c t Article history: Novel polyureas with soft segments based on a difunctional amine, Versalink P-1000, and hard segments Received 15 January 2013 based on Isonate 143L, which is a mixture of difunctional and trifunctional isocyanates, were synthe- Received in revised form sized. The stoichiometric ratio of Isonate 143L to Versalink P-1000 in the polyurea material system 13 March 2013 was incrementally varied. The properties of the resultant polyurea formulations were characterized Accepted 22 March 2013 using dynamic mechanical analysis (DMA) and modulated differential scanning calorimetry (MDSC). The Available online 12 April 2013 dynamic mechanical properties measured as storage and loss moduli were significantly altered through the variation