BACKGROUND: Much research is currently directed towards recycling post‐consumer poly(ethylene terephthalate) (PET) products for both environmental and economic reasons. Aminolysis of PET wastes using different amines, such as allylamine, morpholine, hydrazine and polyamines, leads to different reaction products as diamides of terephthalic acid, which do not possess any potential for further chemical reactions. In the past, the use of ethanolamine has been investigated for the aminolytic degradation of PET waste in the presence of different simple chemicals such as sodium acetate as catalysts. The product obtained, bis(2‐hydroxyethylene) terephthalamide (BHETA), has potential for further reactions to obtain useful products. Nevertheless, there has been no report on using recycled BHETA from PET to synthesize polyurethanes. RESULTS: In this research the product of aminolysis of PET waste, BHETA, was prepared. Then novel polyurethanes were synthesized based on the BHETA prepared, 1,4‐butanediol, ether‐type polyol and various molar ratios of hexamethylene diisocyanate. To evaluate the effect of BHETA, the properties of the polyurethanes without and with BHETA were compared. Fourier transform infrared spectra, thermal transitions, degradation, swelling ratio and chemical resistance of the synthesized polyurethanes were investigated. Also, the polyurethanes were applied as adhesives on various substrates. Comparison of the maximum bond strength of the synthesized polyurethane to that of commercial adhesives shows an about 2.2‐fold increase. CONCLUSION: It is possible to synthesize new polyurethanes with interesting properties using BHETA as an aminolysis product of PET waste. These kinds of materials have potential for many applications, such as adhesives and coatings. Copyright © 2008 Society of Chemical Industry

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Nowadays, developing biocompatible shape memory polymers is among major expanding topics in medical applications. In this study, novel biocompatible polyurethane/graphene nanoplatelet (PU/GNp) nanocomposites were synthesized from poly(ε–caprolactone)diol (PCL diol)/Castor oil and Hexamethylene diisocyanate (HDI) through in situ polymerization. Three different %wt. of GNp were incorporated into the polyol mixtures to monitor the effect of nano fillers on the shape memory behavior of PUs. The chemical structure of nanocomposites was studied by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. X‐ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), and differential scanning calorimetry (DSC) were used to evaluate the nanocomposites properties. GNp incorporation affected the bulk morphology as well as thermal properties and crystallinity. Dynamic mechanical thermal analysis (DMTA) revealed the higher elastic modulus values for nanocomposites compared to the pure PU. The biocompatibility of PU/GNp nanocomposites was investigated via MTT assay. Finally, based on shape memory studies, the higher crystallinity, and improved elastic modulus of the nanocomposites resulted in their excellent shape fixity (about 91‐96%) and shape recovery (95‐99%) behaviors. According to the results, the prepared PU/GNp nanocomposites can be considered as potential choices for applicable shape memory devices for biomedical applications. POLYM. COMPOS., 39:4020–4033, 2018. © 2017 Society of Plastics Engineers

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