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In this work, a variety of hyperbranched polymers (HBPs), such as hyperbranched polycarbonates, polyesters, polyurethanes and polyacetals, was successfully synthesized from castor oil and soybean oil based monomers via a A 2 1 B 3 polycondensation. First, B 3 monomer triols (TriOL), trialdehydes (TriAD), and tricarboxylic acids (TriAC) were obtained by ozonolysis of castor oil and soybean oil with following reductive or oxidative treatment. Their structures were characterized by 1 H NMR and ATR-FTIR spectroscopy as well as electrospray ionization-Time of Flight-mass spectrometry. These trifunctional B 3 monomers were applied in the preparation of HBPs. The resulting HBPs had number averaged molar mass (M n ) up to 9400 g/mol and weight averaged molar mass (M w ) up to 40,000 g/mol. Through adjusting the initial molar ratio of A 2 to B 3 monomers, hydroxyl terminated (from TriOL monomers) or carboxylic acid (from TriAC monomers) terminated HBPs could be obtained. All the HBPs were characterized by 1 H NMR, size exclusion chromatography, and DSC. These HBPs are potential candidates for the synthesis of cross-linked polymeric materials or in biomedical applications.

A new eco-friendly strategy for the preparation of linear and hyperbranched polycarbonates was developed.Our work referred to a one-pot condensation polymerization of various alcohols (diols and triols) with equivalent amounts of eco-friendly dimethyl carbonate (DMC) at 120 C, atmospheric pressure and in 1,4dioxane solution using 4-dimethylaminopyridine (DMAP) or lithium acetylacetonate (LiAcac) as a catalyst. Polymer chains were built by pure transesterification of hydroxyl and methyl carbonate chain ends, and the single byproduct (methanol) was removed using a pressure-equalized addition funnel filled with 4Å molecular sieves as the crucial equipment in this work. Using this strategy, hyperbranched polycarbonates with high molar masses (M n up to 10 000 g mol À1 and M w up to 64 000 g mol À1 ) and high hydroxyl end group contents (up to 94%) were successfully prepared using dimethyl carbonate instead of toxic phosgene or phosgene-based monomers for the first time. In addition, linear aliphatic polycarbonates of various diols were also synthesized with M n up to 16 000 g mol À1 and low molar mass distributions (Đ M < 1.70). Another eco-friendly aspect of this work was the use of equimolar amounts of DMC to avoid waste and the disposal of excess DMC; in a classic 2-step polycondensation for polycarbonate synthesis excess DMC is a prerequisite in order to obtain high molar masses.

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Liquid crystalline behavior of polymeric materials is of considerable current interest in the last decades, but due to many different and distinct characteristics. Polyazomethines liquid crystalline polymers have received considerable attention due to their potential applications and considered as one of the most important liquid crystalline material produced. This review gives a simple introduction to liquid crystalline materials including definition and classification. Moreover, we will focus on the syntheses and properties of liquid crystalline polyazomethines with flexible spacers or hybrid liquid crystalline polyazomethines. Furthermore, give a general overview of thermotropic, mesophoric properties and texture observation for desired liquid crystalline polyazomethines were shown in details.