Unique Photoactive Nanocomposites Based on Rhodamine 6G=Polymer=Montmorillonite Hybrid Systems Adriana Czımerov a, Lubos Jankovicˇ, Jana Madejov a, Alexander  Ceklovsk y Institute of Inorganic Chemistry, Slovak Academy of Sciences, D ubravsk a cesta 9, 845 36 Bratislava, Slovakia Correspondence to: A. Czımerov a (E - mail: Adriana.Czimerova@savba.sk) Received 23 July 2013; accepted 5 September 2013; published online 5 October 2013 DOI: 10.1002/polb.23382 ABSTRACT: An organo-montmorillonite (MMT) complex [poly- diallyldimethyl(PDDA)-Kunipia F] with various loadings of poly- cation was modified with a laser dye Rhodamine 6G (R6G) to obtain a photofunctional hybrid materials for monitoring of dye- polymer-MMT nanocomposite interactions. The polymer-MMTs were prepared in a colloidal state via ion-exchange reaction. The content of polycation (PDDA) in suspensions varied from 20 mg to 1000 mg per 1 g of Kunipia F (KF) MMT. Dramatic changes was observed in the structure of PPDA-MMT containing 200–300 mg of polymer per 1 g of KF, which was the saturation point of the polycation for this system. The PDDA molecules were able to suppress the formation of nonluminescent H-aggregates and to enhance the overall luminescence proper- ties. The PDDA=MMT nanocomposite systems are the novel ones that have not been studied before in order to prepare highly fluorescence hybrid systems. VC 2013 Wiley Periodicals, Inc. J. Polym. Sci. Part B: Polym. Phys. 2013, 51, 1672–1679 KEYWORDS: aggregation; cation exchange; clay; colloids; disper- sions; dyes=pigments; fluorescence; host–guest systems; hybrid inorganic–organic nanocomposites; infrared spectros- copy; inorganic materials; layered silicates; luminescence; molecular assemblies; nanocomposites; photoluminescence INTRODUCTION Encapsulation of photoactive molecules, such as organic dyes, into the gallery of various inorganic materi- als is of a great interest in the developing of new optical and photonic devices, for example, tunable solid-state lasers, double-frequency crystals, solar cells, and so forth. 1–3 Some specific examples of such types of materials should include conjugated polymer nanoparticles, which are highly versatile nanostructured materials that can potentially find applica- tions in various areas such as optoelectronics, photonics, bio- imaging, biosensing, and nanomedicine. 4 Another example of other emitting materials should include intrinsically fluores- cent nanoparticles like colloidal quantum dots; which can be applied to ultrafast optoelectronics, such as optical switches, electro-optical modulators, detectors, or biosensors. 5–9 Such hybrid inorganic–organic nanomaterials based on lay- ered silicates, acting as a solid matrix, are now being investi- gated in order to create suitable templates for guest materials. 10,11 Smectites, a specific group of layered silicates, are often used as an inorganic component for these hybrid materials. Montmorillonite (MMT) is one of the most often studied mineral from the smectite group. The main physico- chemical properties of smectites are related to their ability to exchange cations, unique colloidal and swelling properties. The layers of smectites consist of three building blocks, namely, an octahedral sheet—M(O, OH) 6 (M 5 Al III , Mg II , Fe II , or Fe III ), sandwiched between the two sheets of tetrahe- dral SiO 4 . The smectites possess a net negative charge due to the isomorphic substitutions in the layers, broken bonds, and=or defects in the structure, which is compensated by hydrated inorganic cations in the interlayer space and on the outer surfaces. 12 The smectite particles consist of stacks of 1-nm-thick layers or platelets with a regular gap in the inter- layer space. Their high degree of swelling in water and other solutions make them suitable for the ion-exchange reactions with a great variety of organic compounds, for example, alky- lammonium salts, polymers, or organic dyes. Addition of polymers to smectites results in a formation of nanocompo- sites where the clay particles are well dispersed in a poly- meric phase. Such types of nanocomposites exhibit physical and chemical properties that are dramatically different to those of their bulk counterparts. 13–15 The organic part of nanomaterial hybrid systems, responsible for their photophysical properties, is represented by cationic dye molecules. Simple dye molecules can either be self- assembled to the supramolecular structures, or can create molecular aggregates. In case of aggregates, dye molecules are held together by weak van der Waals or electrostatic forces. The aggregation process significantly affects the VC 2013 Wiley Periodicals, Inc. 1672 JOURNAL OF POLYMER SCIENCE, PART B: POLYMER PHYSICS 2013, 51, 1672–1679 FULL PAPER WWW.POLYMERPHYSICS.ORG JOURNAL OF POLYMER SCIENCE