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Abstract
The bio‐based hyperbranched polyurethanes (HBPUs) have generated immense interest as advanced shape memory materials. In the present investigation, HBPUs were synthesized from poly(ε‐caprolactone)diol as a macroglycol, butanediol as a chain extender, monoglyceride of Mesua ferrea L. seed oil as a bio‐based chain extender, triethanolamine as a branch‐generating moiety (at different percentages), and toluene diisocyanate by a prepolymerization technique using A2 + B3 approach. The structure of the synthesized HBPU was characterized by different techniques. Nuclear magnetic resonance (proton) study indicated the formation of highly branched structure with degree of branching 0.9. The increment of thermal stability from 225 to 260°C and melting point from 50 to 53.5°C with the increase of triethanolamine content was observed. Tensile strength 4–8 MPa, elongation at break 614–814%, impact resistance 0.8–0.95 m, and scratch hardness 2–6 kg increased with the increase of multifunctional moiety content from 0 to 5 wt%. The shape recovery ratio increased with the increase of multifunctional moiety content from 0.21 to 0.95. Thus, the studied HBPUs have the potential to be used as advanced thermoresponsive shape memory materials. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
| Authors: | Kalita, Hemjyoti; Karak, Niranjan | |
| Journal: | Polymer Engineering and Science | |
| Year: | 2012 | |
| Pages: | n/a | |
| DOI: | 10.1002/pen.23200 | |
| Publication date: | 12-05-2012 |
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