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This study reveals insights into the transurethanization reactions leading to the aliphatic-aromatic non-isocyanate poly(carbonate-urethane)s (NIPCUs) and their structure-property relationships. The crucial impact of the alkyl chain length in 4,4'-diphenylmethylene bis(hydroxyalkyl carbamate) (BHAC) on the process of transurethanization reactions was proved. The strong susceptibility of hydroxyethyl- and hydroxybutyl carbamate moieties to the back-biting side reactions was observed due to the formation of thermodynamically stable cyclic products and urea bonds in the BHACs and NIPCUs. When longer alkyl chains (hydroxypentyl-, hydroxyhexyl-, or hydroxydecyl carbamate) were introduced into the BHAC structure, it was not prone to the back-biting side reaction. Both 1 H and 13 C NMR, as well as FT-IR spectroscopies, confirmed the presence of carbonate and urethane (and urea for some of the samples) bonds in the NIPCUs, as well as proved the lack of allophanate and ether groups. The increase in the alkyl chain length (from 5 to 10 carbon atoms) between urethane groups in the NIPCU hard segments resulted in the increase in the elongation at break and crystalline phase content, as well as the decrease in the T g , tensile strength, and hardness. Moreover, the obtained NIPCUs exhibited exceptional mechanical properties (e.g., tensile strength of 40 MPa and elongation at break of 130%).

The presented research focuses on the synthesis and structure-properties relationship of poly(carbonate-urea-urethane) (PCUU) systems including investigations on shape-memory effect capability. Furthermore, we approached the topic from a broader perspective by conducting extensive analysis of the relationship between the synthesized compounds and the results of computer simulations by means of the Monte Carlo method. For the first time, by using a unique simulation tool, the dynamic lattice liquid model (DLL), all steps of multi-step synthesis of these materials were covered by the simulations. Furthermore, broad thermal, mechanical, and thermomechanical characterization of synthesized PCUUs was performed, as well as determining the shape-memory properties. PCUUs exhibited good mechanical properties with a tensile strength above 20 MPa, elongation at break around 800%, and an exhibited shape-memory effect with shape fixity and shape recovery ratios above 94% and 99%, respectively. The dynamic lattice liquid model was employed to show the products and their molar mass distribution, as well as monomer conversion or the dispersity index for individual reaction steps. The results obtained in the following manuscript allow the planning of syntheses for the PCUUs of various structures, including crosslinked and soluble systems, which can provide a broad variety of applications of these materials, as well as a better understanding of the composition-properties relationship.

In this article we report an easy synthetic route towards hyperbranched polyglycerols (Amm-HBPGs) containing trimethylammonium groups and siloxane or hydroxyl end-groups. Siloxane derivatives of Amm-HBPGs were synthesized in an efficient five-step procedure including an anionic ring opening copolymerization of the phthalimide-epoxy monomer with glycidol, followed by reactions with allyl bromide, hydrosililation with hydrogenheptamethyltrisiloxane, hydrazinolysis of phthalimide groups and quaternization of resulting amine groups with methyl iodide. Hydroxyl derivatives were obtained by quaternization of previously reported aminated HBPG's with methyl iodide. Polymeric products were characterized using various NMR techniques, FTIR, and elemental analysis. Both Amm-HBPGs were shown to be effective in catalysis of addition of CO 2 to oxirane. The hydrophilic catalysts showed higher efficiency but synthesis of ethylene carbonate was accompanied by formation of small amounts of ethylene glycol. The siloxane-containing catalyst was easily separable from reaction mixture showing high potential in the process of converting carbon dioxide into valuable chemical raw materials.