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Thermoplastic polyurethane consists of hard and soft segments. The difference in glass transition temperature and thermodynamic incompatibility of these segments results in phase separation and shape memory behavior. In this study, the effect of molecular weight of polyol and the amount of nanoparticles on the phase separation and shape memory behavior of polyurethane nanocomposites were studied. Polyurethane was synthesized using poly(tetramethylene glycol) with molecular weights of 1000 and 2000 g/mol, hexamethylene diisocyanate, and 1,4‐butanediol by step polymerization. The nanocomposites were synthesized through in situ method containing 1 and 2 wt% of nanoparticle. Phase separation and shape memory behaviors were studied using attenuated total reflectance‐Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical thermal analysis, and atomic force microscopy analysis. The results indicated that higher molecular weight polyol with molecular weight of 2000 g mol−1 shows higher phase separation than the lower molecular weight sample. Also, the addition of nanoparticles results in an increased phase separation due to the halloysite nanotubes tendency to the hard segment. The shape fixity ratio (Rf) and shape recovery ratio (Rr) were in the range of 90% to 100% in all of the synthesized samples. By increasing the nanoparticles content, the shape fixity and shape recovery parameters were increased and decreased, respectively. The study of shape memory behavior also showed that the higher the polyol molecular weight, the better the nanocomposite shape memory behavior.

Polyolefins play a crucial role in the polymer industry because of their low-cost monomers and well-established production processes. Recent years have witnessed tremendous progress in direct and tandem copolymerization strategies that provide an opportunity of developing polyolefins bearing polar groups with distinctive architectures and properties. In this perspective, we first highlight new routes for the proficient synthesis of tailor-made functional polyolefins and briefly discuss their designing tactics. Then, we attempt to categorize these, recently appeared in the literature, innovative functional polyolefins on the basis of their applications. The prospected future applications of polar olefin copolymers include biomedical materials, catalysts, energy storage devices, and conductive polymers, which open up new arenas and paradigms for academic research and industrial products development. Critical issues concerning intelligent functional polyolefins and green chemistry are discussed, too.

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Naphtha is one of the crude oil distillation products, bringing almost the lowest value-addition to crude oil, compared to other refinery products such as liquid petroleum gas, gasoline, and diesel. However, Naphtha can be converted to one of the highest value products at the end of the value chain, i.e., polyolefins. Although the production of conventional commodity polyolefins from crude oil, is considered as one of the final products in alkenes’ value chain, there are specialty polyolefins with higher values. Specialty polyolefins are small volume, high-performance thermoplastics with high-profit margins compared to traditional commodity polyolefins. Recently, some special purpose functionalized polyolefins have been developed as efficient substituents for high-performance engineering thermoplastics. Polyolefins are exploited as cost-effective platforms to produce these functionalized thermoplastics. They are promising candidates for replacing high-performance polymers with high-cost raw materials and elaborate production processes. So, functional polyolefins have introduced a new paradigm in the production of high-performance thermoplastics, extending the alkenes’ value chain and increasing profitability. High-performance specialty polyolefins may find exceptional markets in niche applications. In this chapter, the commercial specialty and functional polyolefins’ current situation and prospects are reviewed.