Melt-Moldable Copolymethacrylate/Titania Thermoreversible Polymer Networks with Shape Memory

Abstract

This paper presents a hybrid network system composed of titania and a linear copolymer based on methyl methacrylate (MMA) and methacrylic acid (MA) monomers. The bonding between the carbonyl groups of the MMA and titania in this hybrid network system was inhibited via the addition of tetrabutylphosphonium chloride. Simultaneously, the titania components in the hybrid network system formed thermally reversible bonds with the carboxyl groups of the MA. The proposed hybrid copolymer not only melt molded and maintained a high titania dispersibility but also exhibited excellent 3D shape-memory characteristics. A bulk 3D body composed of multiple layers of the hybrid film achieved a fixed compressed state of approximately 41% that can be restored with a recovery rate of 81% via reheating.

TiO2-Based Nanocomposites Thin Film Having Boosted Photocatalytic Activity for Xenobiotics Water Pollution Remediation

“…Aiming to develop photoactive coatings suitable for water remediation, poly(methyl methacrylate) (PMMA)-based nanocomposites were synthesized through a new approach based on in situ polymerization with Aeroxide ® P25 titanium dioxide nanoparticles (TiO 2 NPs). Bulk in situ polymerization will ensure the establishing of carbonyl–TiO 2 NPs interactions, providing the intercalation of the polymer chains within the TiO 2 NPs porous microstructure [ 27 , 28 ]. To highlight the influence of the polymer on photocatalytic efficiency, the properties of these in situ nanocomposites were compared with those of a blended mixture of the two moieties.…”

Development of a magnetic hybrid material capable of photoinduced phase separation of iron chloride by shape memory and photolithography

“…The E 0 value in this region correlates with the crosslink density because the polymer behaves as an ideal chain. 48,49 The decrease in the crosslink density can be attributed to the reduced accessibility of the silyl group owing to the swelling of TBPC. Therefore, in this sol-gel reaction, the crosslink density of the swollen matrix can be adjusted by adding Ti(OPr) 4 .…”

“…Transparency is a useful parameter to assess the dispersibility of titania, which correlates with the binding force between titania and the polymer side chains in this TBPC hybrid system. 49 For example, when the interaction between titania and the polymer side chain is weak, the transparency decreases and the film appears hazy. In the present system, the covalent bonding of the silane group to titania led to the high dispersibility of the latter, resulting in films with good transparency.…”

“…Hybrid films were prepared according to a previous publication. 48,49 Poly(MMA-co-MSi) was dissolved in 80 mL of THF and added dropwise to a TiOPr (15 wt% based on the copolymer), TBPC (40 wt% based on the copolymer), and FeCl 3 (0, 5, 10 and 15 wt% based on the copolymer) solution. Subsequently, 25 mL of 1.0 M HCl was added dropwise to the mixture and stirred at 20 1C for 15 min.…”

“…Previous publications report improvement of toughness and shape memory properties of titaniacrosslinked PMMA-based hybrid network polymers on addition of tetrabutylphosphonium chloride (TBPC). 48,49 Quaternary phosphonium cations form complexes with various transition metal chlorides. Addition of Fe chloride to the PMMA/titania/ TBPC system yielded a highly dispersed hybrid polymer with FeCl 4…”