Search

Intelligent breathable polyurethane (PU) that is easily allowable for vapor transmission at critical temperature would have significant implication for numerous applications; however, fabrication of such materials has proven to be tremendously challenging. Herein, we reported novel breathable polyurethane material covalently modified with carbon nanotubes (CNTs). When an optimal amount of CNTs (0.5 wt%) was added, the resultant PU film presented high waterproofness with hydrostatic pressure up to 10.9 kPa, as well as enhanced mechanical properties with a tensile strength of 22.2 kPa and elongation at break of 990%. This smart PU film has a significant increase in water vapor transmission rate between 18°C (1400 g/(m2·d)) and 38°C (3440 g/(m2·d)). The type of intelligent polyurethane material is a promising candidate for applications in areas such as protective clothing, separator media, and wearable electronics. [ABSTRACT FROM PUBLISHER]

Using hydroxylated carbon nanotubes (CNT-OH) as a crosslinking agent, covalently modified CNT/3,3′-bisazidomethyloxetane-3-azidomethyl-3′-methyloxetane (BAMO-AMMO) thermoset polyurethane elastomers with different CNT-OH content were prepared, and their structure and performance were analyzed. At a CNT-OH mass fraction of 1.0 wt%, the elongation ratio was 380% and the tensile strength was measured to be as high as 10.4 MPa, which is an 82.5% improvement compared to traditional trimethylolethane (TME)/BAMO-AMMO energetic binders. The measured onset decomposition temperature (i.e., the temperature with 5% weight loss) was 236°C, which is 7°C higher than that of corresponding TME/BAMO-AMMO energetic binders. Furthermore, the identified glass transition temperature (Tg) was −34°C. [ABSTRACT FROM PUBLISHER]