J Alloys Compd 2013, 551:481–484.CrossRef Competing interests The authors declare that they have no competing interests. Authors’ contributions DGC and TJ carried out the synthesis, crystallization methodology and photocatalytic studies, participated in the morphological characterization and drafted the manuscript. MP carried out the microscopy characterization and PP2 chemical structure helped to draft the manuscript. ACC and DFH conceived of the study and participated in its design and coordination. All authors read and approved the final manuscript.”
“Background

Graphene has attracted intensive interest due to its extraordinary electrical, thermal, and mechanical properties [1, 2]. Among its wide range of applications, recent studies have demonstrated that polymer nanocomposites based on graphene have resulted in dramatic improvements in the mechanical, electrical, and gas barrier properties of pristine polymers [3–6]. Homogeneous IACS-10759 dispersion of graphene in the polymer matrix is an

essential requirement to obtain the desired properties. Graphene oxide (GO) with abundant oxygen-containing groups, such as epoxy, hydroxyl, and carboxyl, can be well dispersed in a polymer matrix due to its good interaction with polymer chains [7–9]. However, the agglomeration of graphene sheets due to van der Waals forces only allows for a successful colloidal suspension within a narrow range of organic solvents. Park et al. reported that highly reduced graphene oxide was dispersed Vasopressin Receptor in organic Captisol in vivo solvents with a sum of solubility parameters (δp and δH) in the range of 13 to 29 [10]. Recently, it was reported that alkylamine-functionalized graphene oxide (FGO) exhibited good dispersion in solvents and a strong interfacial interaction with low-polar organic solvents and polymers [11–17]. GO modified with HDA showed superior dispersion up to 7 mg/mL in organic solvents with low Hansen solubility parameters, such as xylene and toluene [18]. Thus, they could be effectively used as a nanofiller even in low-polar polymers such as polyethylene [19, 20]. In this work, three alkylamines, OA, DDA, and HDA, with different alkyl chain lengths were

utilized to examine the effect of alkylamine functionalization of GO on the properties of FGO/PS composites. When the FGO/PS nanocomposites were prepared by solution blending, the FGOs were homogeneously dispersed over the PS matrix even at a high concentration in chloroform. Methods Preparation of FGO and FGO/PS nanocomposites GO was prepared by a modified Hummers method using expanded graphite (Grade 1721, Asbury Carbons, Asbury, NJ, USA) which was heated for 10 s in a microwave oven. The ratio of GO to alkylamines (CH3(CH2)7NH2, CH3(CH2)11NH2, CH3(CH2)15NH2, Sigma Aldrich, St. Louis, MO, USA) was fixed at 1.0 g of GO to 0.01 mol of alkylamine. The alkylamine solutions were prepared by dissolving 0.010 mol of OA, DDA, or HDA in 30 mL of ethanol (SK Chemicals, Gyeonggi-do, Korea).