Complementary Multiple Hydrogen Bonding Interactions Induce the Self-Assembly of Supramolecular Structures from Heteronucleobase-Functionalized Benzoxazine and Polyhedral Oligomeric Silsesquioxane Nanoparticles

Abstract

We prepared octuply adenine (A)-functionalized polyhedral oligomeric silsesquioxane [(octakis­(vinylbenzyladenine-siloxy)­silsesquioxane, OBA-POSS] nanoparticles through the reaction of A with octakis­(benzyl chloride) POSS (OVBC-POSS), itself prepared through hydrosilylation of octakis­(dimethylsiloxy)­silsesquioxane (Q8M8 H) with vinyl benzyl chloride. We observed the self-assembly of lamellar structures from the complexation of a thymine (T)-functionalized polybenzoxazine (PA-T) with OBA-POSS, stabilized through complementary multiple hydrogen bonding interactions between the T groups of PA-T and the A groups of OBA-POSS. In addition, incorporating POSS presenting multiple, strong, complementary hydrogen bonding A units into the PA-T matrix significantly enhanced the thermal stability of this polymer, as evidenced using differential scanning calorimetry and thermogravimetric analysis.

Strong Screening Effect of Polyhedral Oligomeric Silsesquioxanes (POSS) Nanoparticles on Hydrogen Bonded Polymer Blends

“…POSS derivatives are interesting materials because one or more of their organic groups can be functionalized for polymerization, while their remaining unreactive groups can be designed to solubilize the inorganic core and control the interfacial interactions between the POSS units and the polymer matrix. Due to their potential for advanced performance (e.g., high thermal stability; low flammability; low dielectric constant; low surface energy) relative to nonhybrid counterparts, POSS-polymer hybrid materials have attracted great interest recently [26][27][28][29][30][31][32][33][34][35]. We observed a "screening effect" in phenolic/PMMA-POSS blends arising from the tethered POSS units at the chain ends, with the inter-association equilibrium …”

Highly Efficient Route for the Synthesis of a Novel Generation of Tetraorganofunctional Double‐decker Type of Silsesquioxanes

“…per one mole SiÀ H group). Products 3 a-h and 3 i-k were isolated by column chromatography purification in high yields (78-97 %), vacuum dried and analyzed with 1 H, 13 C, 29 Si NMR, IR and MALDI-TOF and TOF MS confirming their structures. Even with the use of [Pt (IPr*)(dvds)], the hydrosilylation of styrene also gave a mixture of β/α = 78/22 product, contrary to its high selectivity in HS of simple silanes.…”

“…At the same time, chemists are looking for synthetic routes exploiting among others hydrosilylation reaction to obtain novel, functionalized Si-based reagents with a specific structure such as silsesquioxanes. [17][18][19][20][21][22][23][24][25][26][27] While hydrosilylation of olefins with silanes has been widely studied, [3,28] the reports on T 8 silsesquioxanes are limited [5,6,[29][30][31][32][33][34] and for double-decker systems of both closed (D 2 T 8 [4,19,25,[35][36][37] ) and opened (M 4 T 8 [38][39][40][41][42][43] ) structure even more scant. [5] Cage-like derivatives have driven much attention due to specific physicochemical properties (governed by the nature of their silicate rigid core and by the number and type of functional groups attached to it) affecting directions of their broad applications from material chemistry to medicine.…”

Synthesis of eugenol-based polybenzoxazine-POSS nanocomposites for low dielectric applications

“…Some efforts to increase crosslinking density and glass transition temperature, improve thermal stability and flame resistance, enhance toughness and flexibility, and reduce dielectric constants have been reported . To further improve the performance of polybenzoxazines, blending with other polymers such as epoxy, polyurethane, poly (N‐vinyl‐2‐pyrrolidone), or organic–inorganic hybrid systems such as clay, polyhedral oligomeric silsesquioxane (POSS), and poly (imide‐siloxane) or carbon nanotubes have been successfully adopted .…”