File(s) under permanent embargo
Reason: This item is currently closed access.
Sub-surface and bulk creep behaviour of polyurethane/clay nanocomposites
journal contributionposted on 23.06.2015, 13:56 by Jie Jin, Kamal Yusoh, H.X. Zhang, Mo Song
A series of exfoliated and intercalated polyurethane organoclay nanocomposites were prepared by in situ polymerization of polyol/organoclay mixture, chain extender and diisocyanate. The creep behaviour of subsurface and bulk of the polyurethane coatings was investigated by nanoindentation technique and uniaxial conventional creep testing method, respectively. The results showed that the creep resistance of the nanocomposites was significantly improved by incorporation of organoclay. The enhancement of creep resistance was dependent on clay content as well as organoclay structure (exfoliation or intercalation) in the polymer matrix. With 1wt% organoclay, the creep resistance increased by about 50% for the intercalated organoclay and 6% for the exfoliated organoclay systems, respectively, compared to the pristine polyurethane. Viscoelastic model was employed to investigate the effect of organoclay loadings on the creep performance of the polyurethane. Results showed the model was in good agreement with the experimental data. Incorporation of clay leads to an increase in elastic deformation especially in exfoliated polyurethane nanocomposites and induces a higher initial displacement at the early stage of creep.
We thank EPSRC (UK) for providing funding [grant number EP/G042756] for this work.
- Aeronautical, Automotive, Chemical and Materials Engineering