Solutions of amorphous poly(d,l‐lactide‐co‐trimethylene carbonate)s (PDLTMCs) in ethyl acetate work as solvent‐based physical adhesives through diffusion mechanisms for a variety of aliphatic polyester‐based adherents. The random PDLTMCs with a trimethylene carbonate content of 11, 16, and 20 mol% are synthesized in bulk, achieving high molecular weight, Mn, up to 128 kg mol−1 and dispersity around 1.7. The PDLTMCs are amorphous and have a glass transition temperature in the range 34.7 to 43.6 °C and in agreement with the theoretical values calculated using the Fox equation. The mechanical and surface properties of the PDLTMCs are tested preparing solvent cast films, which are soft and tough and, although they have a higher contact angle than the parent homopolymer, they show higher water uptake capacity. The potential application as adhesives of the synthesized PDLTMCs is evaluated by preparing a 20 wt% solution in ethyl acetate and testing them by adhering films with different compositions as well as constructs having different geometries and surface roughness. The results demonstrate that the adhesion strength is higher on adherent films having similar chemical compositions as the adhesives and on surfaces having similar compositions to each other but different roughness. The similar chemical nature of the adhesive and adherent probably favors the diffusion mechanism through which adhesion takes place.

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The investigation of pH dependence on the synthesis of gold nanoparticles capped Na-citrate from adsorbed Au(III) and Au(0) on salicylic acid immobilized hydotalcite had been carried out under ultrasound irradiation. Evidenced by UV-visible spectrophotometer, pH 3.0 revealed to be the optimum condition where gold nanoparticles show the evidence of surface plasmon resonance (SPR) at 547 nm. The deprotonation of 1-and 2-carboxylic groups of capping agent citrate was lead to the forming of [C6H6O7] 2-which acts as both reduction and desorption agents of Au(III) and Au(0), respectively. Characterization using X-ray diffraction and transmission electron microscopy supported the successful synthesis of gold nanoparticles by the appearance of gold lattice index (111; 200; 220 and 311) and 2D nanoparticles image with the average size of 84.72 nm.