This paper aims to investigate the influence of the mold temperature on the mechanical responses at different ambient temperature and molecular structure of the injection molded TPU sheets. The tensile properties of the TPU sheets prepared at different mold temperatures were obtained at different ambient temperatures. As the mold temperature increases, both the elongation at break and tensile strength of the specimens increase. The specimens show yield behavior during stretching at −30 and −50°C. The microstructure of the TPU sheets was characterized by DMA, AFM, and birefringence. The results show that the higher mold temperature can reduce the aggregation of hard domains because of the higher mobility of the hard segments. In‐situ SAXS and WAXS measurements were carried out at −30°C test temperature to exhibit the evolution of the microstructure during stretching. When the specimens are prepared at 40°C mold temperature, the hard domains are destroyed and difficult to orient along the stretching direction. In contrast, the hard domains begin to be deformed and oriented along the stretching direction above the yield strain when the specimens molded at higher mold temperature. The above microstructure evolution is consistent with the tensile behavior of the TPU specimens.

The use of injection molding technology to prepare heterogeneous interlayer film of laminated glass holds strong applicable potential. This article aims to investigate the effects of melt temperature and melt flow on the microstructure evolution and tensile properties of thermoplastic polyurethane (TPU) specimens during the injection molding process. The tensile properties of the TPU specimens show dependency on the melt temperature and melt flow direction. The results of birefringence indicate that melt flow and lower melt temperature induce higher stretching deformation of the molecular chain network. Small-angle X-ray scattering analysis approves that besides the melt temperature and flow direction, the testing position on the cross section of the specimen has great influence on the microstructure of the TPU sheet. Further analysis and conclusions can be made using wide-angle X-ray scattering method. The above results demonstrate that both the tensile properties and microstructure of the injection molded TPU specimens tend to be isotropic with the increase of melt temperature.

For purpose of reducing chlorine ions entering the wet flue gas desulfurazition (WFGD) tower to realize the WFGD waste water sequestration and the gypsum upgrading, a technical method of adsorbent injection into flue gas to remove HCl was proposed in this work. A new NaOH-modified CaO (CA-MC-NA) was prepared by the mechanochemical ball milling method as a superior adsorbent for HCl removal in flue gas. The influence of particle size and Na doping on the dechlorination efficiency and chlorine capacity was investigated in a fixed bed reaction system. The experimental results demonstrated that the HCl removal performance is improved significantly under proper particle size and Na doping, as manifested by the experiment results that the chlorine capacity increases from 27.18 to 38.36 mg/g by simple mechanical ball milling, while it surprisingly reaches 75.36 mg/g by doping 5 wt.% NaOH. The surface physicochemical characteristics was explored by combined sample characterization of BET, XRD, SEM, elemental mapping, and particle size distribution. Dechlorination mechanism of the adsorbents were deduced and discussed. It shows that the mechanical ball milling process reduces the particle sizes to the submicron scale that induces the break and reconstruction of molecular interfacial bonds. It also increases the oxygen defects on the adsorbent surface. The doping of NaOH does not change the crystal structure of the dechlorinator, and Na ions can be chemically loaded over CaO in the form of ionic bonds.Free oxygen atoms or adsorbed oxygen molecules could combine with dissociated hydrogen atoms thus forming hydroxide radicals, which enhances the alkalinity of the adsorbent and boosts the removal of hydrogen chloride.

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