Gold nanoparticles (AuNPs) are attractive materials due to their special optical and electronic properties. However, they tend to aggregate particularly in the presence of thiol‐containing compounds. In this study, to investigate the effect of surface conjugation with thiol‐containing compounds on colloidal stability, thiol compounds with various structures as modifying agents were used. To this end, AuNPs were synthesized and stabilized by trisodium citrate in aqueous solution, and then modified with thiol‐containing compounds, namely cysteamine hydrochloride (MEA, containing primary amine groups), 2‐mercaptoethanol (BME, containing hydroxyl groups), 1‐dodecanthiol (LCA, containing long‐chain alkyl groups) and thioglycolic acid (TGA, containing carboxylic acid groups). We studied the effect of thiol ligands on solution stability of colloidal AuNPs and on the formation of aggregates originating from the modification process using UV–visible spectroscopy, dynamic light scattering, field emission scanning electron microscopy and transmission electron microscopy. Results showed that surface modification with MEA, BME and LCA led to the formation of aggregates. However, conjugation with TGA showed a concentration‐dependent behaviour: surface modification with low concentration resulted in the formation of aggregates whereas that with high concentration of TGA did not disturb the colloidal stability of AuNPs. Finally, the effect of surface modification on temperature increase of solutions originating from infrared light irradiation was studied, where the temperature increase depends on the surface‐modifying compound.

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The main disadvantages of polysulfide polymers are their complicated curing systems and their low solubility in different solvents. To overcome these problems, bis(oxiranylmethyl)sulfanes as new epoxide‐terminated polysulfide prepolymers were synthesized and their amine‐cured polymers were examined by different analysis methods. 1H NMR, 13C NMR, and FT‐IR have been used to characterize structure of the synthesized prepolymers and polymers and sulfur content of all samples has been investigated by CHNS elemental analysis. X‐ray diffraction analysis showed that all samples were semi‐crystalline and differential scanning calorimetry was used to study thermal transitions of prepolymers and polymers. As an advantage, all prepolymers and linear polymers were dissolved in sulfur‐ and nitrogen‐containing solvents. Synthesized polymers had low thermal stability with one‐step degradation process and they were in rubbery state with Tg values lower than 0°C. Conclusively, thermophysical properties of polymers depended on utilized prepolymer and amine‐containing compounds as precursors.