Synthesis and properties of polyhydroxyurethane bearing silicone backbone

Soft-Segment Containing Lignin-Based Polyhydroxyurethanes: Controllable Flexibility Through PDMS Integration

Lignin, a biomass-derived polymer, is rich in aromatic groups composed of phenylpropane units, providing rigidity, thermal stability, and mechanical strength ideal for structural applications. However, its inherent stiffness limits flexibility. To address this, lignin is copolymerized with bis(3-aminopropyl)-terminated poly(dimethylsiloxane) (PDMS-NH2), introducing tunable elasticity and improved mechanical properties. Lignin is first modified with CO₂ to produce cyclic carbonate-functionalized lignin (CCL). The CCL reacts with PDMS-NH2 amines via the ring-opening of cyclic carbonates, forming soft-hard polyhydroxyurethane copolymers with adjustable properties (CCL-PDMS-PHUs). Structural characterization confirms urethane bond formation, with peaks at 1680 cm⁻¹ (FT-IR) and chemical shifts at 161.33 ppm (¹3C NMR) and 7.99 ppm (¹H NMR). Thermal analysis reveals 5% decomposition temperatures of 246-265 °C and glass transition temperatures (Tg) ranging from 44 to 66 °C, indicating tunable thermal stability. Mechanical testing shows that CCL-PDMS-PHU60 (60% PDMS-NH2) exhibited greater softness, while CCL-PDMS-PHU40 (40% PDMS-NH2) displayed higher stiffness, highlighting PDMS-NH2's effect on flexibility. These results demonstrate that CCL-PDMS-PHUs offer customizable mechanical and thermal properties, making them promising materials for applications requiring tailored elasticity and thermal performance.

Solubility-governed architectural design of polyhydroxyurethane-graft-poly(ε-caprolactone) copolymers

Polyhydroxyurethane-graft-poly(ε-caprolactone) copolymers were prepared in bulk by designing a polyhydroxyurethane system with polymer-in-monomer solubility.

Hybrid Poly(hydroxy urethane)s: Folded-Sheet Morphology and Thermoreversible Adhesion

Hybrid poly(hydroxy urethane)s (PHUs) are synthesized by copolymerizing aromatic/alicyclic cyclic carbonates with a polyether amine via addition polymerization. They result into polymers with an average molecular weight of 10 kDa and exhibit solubility in common organic solvents. The hybrid PHUs display T g up to 18 °C. PHUs are enriched with multiple H-bonded interactions and they are assessed using temperature-dependent 1H NMR and Fourier-transform infrared studies. PHUs possess folded-sheet morphology with nanogap between folds and nanowidth between chains. The secondary interactions bestow thermoreversible property to PHUs, and they display good adhesion to both polar (Al-Al) and nonpolar (HDPE-HDPE) substrates. Hybrid PHUs show improved optical transparency compared to homo PHUs. The PHUs are thermally stable up to 250 °C.

Synthesis of self-healable waterborne isocyanate-free poly(hydroxyurethane)-based supramolecular networks by ionic interactions

A novel synthetic strategy to isocyanate-free supramolecular polyhydroxyurethanes based on ionic interactions is described.

Reworkable Polyhydroxyurethane Films with Reversible Acetal Networks Obtained from Multifunctional Six-Membered Cyclic Carbonates

Multifunctional 6-membered cyclic carbonates (6-CCs) comprising acetal structures have been synthesized via phosgene-free routes and utilized for the fabrication of reworkable networked poly(acetal-hydroxyurethane) (PAHU) films. Dibenzoyl-protected di(trimethylolpropane) (DTMP) reacts with multifunctional aldehydes derived from nonexpensive alcohols to afford protected multifunctional DTMPs. After deprotection, the multifunctional DTMPs can react with diphenyl carbonate to efficiently form multifunctional 6-CCs. The polyaddition of the 6-CCs and diamines effectively proceeds in DMF to give networked PAHU films with good transparency and flexibility. These films possess the reworkability based on acid-catalyzed reversibility of acetal linkages. In particular, the film fabricated using large amounts of hexa-functional 6-CCs can reform reproducibly with maintaining to some degree its mechanical properties.

Synthesis and characterization of polyurethanes bearing carbosilane segments

New polyurethanes bearing carbosilane segment (1a–c) were synthesized and found to exhibit lower glass transition temperature and storage moduli than corresponding reference polyurethanes 2a–c, while thermal stability was retained.

Room temperature synthesis of non-isocyanate polyurethanes (NIPUs) using highly reactive N-substituted 8-membered cyclic carbonates

Non-isocyanate polyurethanes (NIPUs) were prepared via polyaddition of highly reactive 8-membered ‘bis-cyclic’ carbonates and various diamines under catalyst-free and room temperature conditions.

Synthesis and hydrolytic properties of water-soluble poly(carbonate–hydroxyurethane)s from trimethylolpropane

Water-soluble poly(carbonate–hydroxyurethane)s with sodium carboxylate side chains synthesized from trimethylolpropaneviaphosgene derivative- and isocyanate-free routes are rapidly degradable to their small components in weak alkaline aqueous environments.

Synthesis of polyhydroxyurethanes from di(trimethylolpropane) and their application to quaternary ammonium chloride-functionalized films

Polyhydroxyurethanes synthesized using non-isocyanate and non-phosgene derivatives afford quaternary ammonium chloride (QAC)-functionalized films after chloroacetylation and quaternization with cross-linkable amines.