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Thermally induced polymerizations of a series of 1,3‐benzoxazines with a variety of substituents on the nitrogen atom were investigated in detail, particularly in the following three aspects of the polymerization: (1) N‐alkyl‐1,3‐benzoxazines are much more reactive than N‐phenyl‐1,3‐benzoxazine. (2) The polymerization rate depended on the bulkiness of the N‐substituent. The bulkier the substituent was, the slower the polymerization was. (3) The polymerizations accompanied weight loss due to the elimination of the corresponding imine (R‐N = CH2), and its extent became larger when R was more bulky. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2777–2782, 2010

Zinc glutarates were synthesized from zinc oxides with varying purities via different stirring routes. The particle size and structure of these zinc glutarates were determined by wide‐angle X‐ray diffraction, transmission electron microscopy, and the laser particle size analyzer technique. The results demonstrated that the crystallinity and crystalline perfectness of zinc glutarate are the crucial factors that affect the catalytic activity for the copolymerization of carbon dioxide (CO2) and propylene oxide (PO). Additionally, the catalyst with a small particle size dramatically increased the yield of the copolymerization between CO2 and PO. High‐molecular‐weight and regular molecular structure poly(propylene carbonate)s (PPC)s were obtained from CO2 and PO with the synthesized zinc glutarates. Very high catalytic activity of 160.4 g polymer/g catalyst was afforded. The NMR technique revealed that the PPC copolymer exhibits an exact alternating copolymer structure. The relationships between the crystallinity and the particle size of catalyst with the catalytic activity are correlated and discussed. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3579–3591, 2002

In this paper, a mixture system without water but composed of monoethanolamine (MEA) and triethylene glycol (TEG) is designed for CO 2 capture. The solubility of CO 2 in pure TEG and MEA-TEG solutions is determined, respectively, showing that the solubility of CO 2 in TEG is generally consistent with Henry's Law and the value is higher than that in water. The solubility of CO 2 in MEA-TEG solutions significantly increases with the increase of MEA, showing the characteristics of chemical reaction absorption. The absorption mechanism study shows that TEG does not act as a reaction agent. There is only one reaction between CO 2 and MEA. The absence of water in the new system leads to the absence of dissociation of protonated MEA and formation of carbamate (MEACOO -). This is much different from the MEA-water system. A mathematical model is also developed for predicting the solubility of CO 2 in the new system. The results show that the absorption and desorption can be realized at relatively lower temperatures (lower than 353.15 K), which may provide advancement in two aspects: low energy consumption with less solvent evaporation and avoidance of MEA's degradation caused by high-temperature operation.

High yield and pure zinc glutarate catalysts used for copolymerization of carbon dioxide and propylene oxide have been synthesized in different solvents by ultrasonic methodology. For the purposes of comparison, low-yield zinc glutarates were also synthesized via mechanical stirring method with other synthetic conditions remaining unchanged. Fourier Transform Infrared Spectroscopy and wide-angle X-ray diffraction techniques confirmed the presence of high-quality zinc glutarate catalysts. Accordingly, poly(propylene carbonate) (PPC) can be synthesized from carbon dioxide and propylene oxide using the zinc glutarate catalysts. It was confirmed that the as-prepared PPC had an alternating copolymer structure together with high molecular weight. The thermal and mechanical properties of the obtained PPC copolymer were determined by means of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile test. DSC and TGA results showed that the PPC copolymer exhibited high glass transition temperature (39.39°C) and decomposition temperature (278°C) when compared to their corresponding values reported in the literature. Tensile test showed that the PPC film exhibited superior mechanical strength.

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High molecular weight and regular molecular structure poly(propylene carbonate) (PPC) was successfully synthesized from carbon dioxide and propylene oxide. The PPC copolymer structure was an exact alternating copolymer as evidenced by the 13 C-NMR technique. Degradative behavior of the PPC was conducted by soil burial and buffer solution immersion (pH ϭ 6) tests, respectively. The results showed that the weight loss of soil buried in PPC films increased more slowly than that immersed in the buffer solution after 6-month exposure. However, the weight loss of sample immersed in the buffer solution increased rapidly during the first 2 months and reached a value of 4.59%. Water sorption measurement also revealed that the PPC membranes immersed in buffer solution were more hydrophilic than those in soil burial tests. The degradation mechanism of PPC membranes was correlated with the sample morphologies, FTIR, and 1 H-NMR spectra. The SEM morphologies were consistent with the weight loss and water sorption measurements.