Reversible Color Changes in Lamella Hybrids of Poly(diacetylenecarboxylates) Incorporated in Layered Double Hydroxide Nanosheets

Abstract

The present study is an investigation of a reversible thermal color change induced in lamella hybrids of poly(diacetylenecarboxylates) incorporated in layered double hydroxide (LDH) nanosheets. These poly-[m,n]/LDH hybrids prepared by the photo- or gamma-ray-induced polymerization of diacetylenecarboxylates, i.e., CH(3)(CH(2))(m)()(-)(1)CC-CC(CH(2))(n)()(-)(1)CO(2)(-) (mono-[m,n]), and intercalated in LDH lamella sheets, were observed to develop colors ranging from yellow to blue. The change in color was found to depend greatly on the alkyl carbon numbers of the mono-[m,n] (m,n = 10,11; 5,11; 10,5; 16,1) values. Moreover, the conformational alignment of the mono-[m,n] within the LDH was observed to be a crucial factor in color development, which was greatly affected by the intercalation degrees and extent of poly(ene-yne) linkage elongation of the polymers. For the poly-[m,n]/LDH hybrids investigated, a reversible color change was found to occur repeatedly and remarkably for the poly-[10,11]/LDH hybrid. This color change occurred at temperatures between ca. 20 and 80 degrees C back and forth from purple red to bright orange, in stark contrast to the irreversible color change for poly-[10,11] without LDH. Moreover, DSC and Raman spectroscopic studies of the LDH hybrids showed that the thermochromic temperature corresponded to the phase transition temperature of 80 degrees C. XRD analysis also indicated that the poly-[m,n]/LDH hybrid could retain its lamella structure during such thermochromic color changes, enabling conformational recovery in the polymer chains by a cooling down of the hybrids to temperatures lower than the transition temperature, while the nonhybrid poly-[10,11] powders exhibited an irreversible color change at 60 degrees C, above which the polymer powder turned amorphous.

Confinement of a Nonionic Surfactant Membrane Within a Montmorillonite as a New Way to Prepare Organoclay Materials

“…Electron density distribution analysis in Figure 5 which represents the electron density distribution of the organoclay, estimated by the relation of ρ(x) against x (Equation (2)), supports the view that organoclay consists of alternatively stacked units of a bilayer sandwiched by clay platelets 20 . The X-ray diffraction patterns of the C 10 E 3 -organoclay show several diffraction peaks at the q located at 0.163, 0.34, 0.48 and 0.66 Å -1 .…”

Factors Affecting the Interlayer Arrangement of Transition Metal–Ethylenediaminetetraacetate Complexes Intercalated in Mg/Al Layered Double Hydroxides

“…[8] In general, the arrangement of interlayer guest anions can dramatically influence the physicochemical properties of LDH materials. [15][16][17][18] For example, in the case of poly(diacetylenecarboxylates) incorporated in LDHs, the possibility of having different arrangements of interlayer guests is responsible for the observed reversible thermal color changes. [18] In developing such functional materials it is important to be able to control the orientation of functional guest anions in the interlayer galleries in order to fully uti-lize their anisotropic properties.…”

“…[15][16][17][18] For example, in the case of poly(diacetylenecarboxylates) incorporated in LDHs, the possibility of having different arrangements of interlayer guests is responsible for the observed reversible thermal color changes. [18] In developing such functional materials it is important to be able to control the orientation of functional guest anions in the interlayer galleries in order to fully uti-lize their anisotropic properties. An understanding of the factors controlling the interlayer arrangement is important if tailored applications in areas such as those mentioned above are to be found for LDHs containing [M(edta)] 2-complexes, but no such study has been reported to date.…”

Surface Layer‐by‐Layer Chemical Deposition Reaction for Nanosized Thin‐Film Formation of Metal Complexes of 2‐Mercaptonicotinic Acid

“…These materials were extensively investigated and evaluated as chemosensors and photonic materials. [14,15] Alternative deposition of oppositely charged linear polymers was also reported for the development of PDAbased chemosensors in layered PDA systems. [16] Zirconium oxide films were produced by sequential LBL adsorption of diluted zirconium alkoxide solutions onto a silicon wafer.…”