Design of nanostructured hybrid materials: twin polymerization of urethane-based twin prepolymers

Abstract

Organic–inorganic hybrid materials with urethane functionalities were obtained by simultaneous twin polymerization of twin prepolymers in combination with the twin monomer 2,2′-spirobi[4H-1,3,2-benzodioxasiline].

Twin Polymerization: A Unique Strategy towards Versatile Functional Materials

“…Schreiter and coworkers extended the class of twin monomers for their use in STP. [83] Urethane-based twin mono-Scheme 2. a) Acid-catalyzed TP of 2,2'-spirobi[benzo-4H-1,3,2-dioxasiline], b) thermally induced formation of the corresponding nanostructured hybrid materials and c) base-catalyzed TP. [15,16] (10) to design nanostructured organic-inorganic hybrid materials as shown in Scheme 4.…”

“…[15,16] (10) to design nanostructured organic-inorganic hybrid materials as shown in Scheme 4. [83] STP of 1 with 8 a,b produced hybrid materials, which are composed of three parts: phenolic resin, silica and dialkylsiloxane-crosslinked polyurethane. [83] They demonstrated further that the respective backbone in 8 a,b effects the trigger temperature of the TP process.…”

“…[83] STP of 1 with 8 a,b produced hybrid materials, which are composed of three parts: phenolic resin, silica and dialkylsiloxane-crosslinked polyurethane. [83] They demonstrated further that the respective backbone in 8 a,b effects the trigger temperature of the TP process. STP of 8 a,b with 1 gave nanostructured hybrid materials with interpenetrating networks of phenolic resin, SiO 2 and dialkylsiloxane-crosslinked urethane structures in a "onepot" synthetic process, whereby the different networks were formed on the same time scale and hence phase separation was very small.…”

“…The described polymerization represents a novel procedure for incorporating different types of Si and phenolic resin into nanoscale urethane formulations. [83] STP processes were also used to access amino functionalities bearing organic-inorganic hybrid materials for joining, for example, aluminum alloys and thermoplastic fiber-reinforced parts, to achieve metal-based hybrid laminates including aluminum combined with thermoplastics such as polyamide-6, enhancing the adhesion behavior between the two parts. [84] Monomers 1 and 10 were applied as twin monomers in a ratio of 15 : 85, whereby a medial tensile shear strength of 12.9 � 3.9 MPa could be reached, which is a remarkable improvement of 230 % as compared to untreated substrates and 120 % compared to technical adhesion promoters (e. g., Verstamelt ® ).…”

“…Procedure for the preparation of urethane-based twin prepolymers 8 a,b (top) and their STP with 1 to obtain hybrid materials consisting of phenolic resin, silica and dialkylsiloxane-crosslinked polyurethane (PPG = polypropylene glycol, PTMEG = polytetramethylene ether glycol, MDI = methylendi(phenylisocyanate)) (middle). HAADF-STEM images of the as-obtained hybrid materials using different reaction conditions (bottom), [83] adapted from reference [83] with permission from RSC.…”