Development and Characterization of Polydimethylsiloxane and Carbon black Composites for Photo Actuation

Abstract

There has been a rapid increase in the number of multidisciplinary research activities in the last two decades. The limits between disciplines are narrowing, as scientists in distinct areas coming up with intriguing concepts that combine expertise in a distinct field. The motive behind this multidisciplinary research arises from nature. Nature inspires us to mimic or generate thoughts for different applications that can enhance or change the requirements of society. The objective of the present research is to develop a photo actuator using composite material for microcantilevers, micro-grippers, micro-robots, photo-switches, micromotors, energy harvesting, and other smart photo devices. The cantilever beam is designed as a single and bilayer structure, actuated by photothermal action. It consists of polydimethylsiloxane and carbon black composites. Thus, there is thermomechanical deformation owing to the difference in the coefficient of thermal expansion as well as the rise in the thermal conductivity of the composite material. The composite beam also induces thermal stress due to differences in the temperature of the beam involved in the adsorption of the light source. The methods engaged in the current investigation of the photo actuator are empirical, numerical (Finite Element) modeling, analytical, and composite material processing and characterization. The empirical model has been used to comprehend and compare the properties of the composite material. Also, material modeling of more significant characterizations is being studied using numerically. The carbon black and polydimethylsiloxane materials have been procured, and the composites have been synthesized using the solution casting technique. Composite properties have been studied by performing various characterization tests for physical, mechanical, thermal, optical, dielectric, and microstructure. Analytical and numerical studies were implemented to investigate the optimum value by varying the thickness and volume percentage of the filler material at different temperatures. The photo actuation test setup was built, and thex composite beam has been tested. Finally, the proposed conceptual model was developed and tested in the laboratory environment. The approach of empirical and numerical (Finite Element) material modeling, composite material characterization, analytical and numerical modeling of actuator models, and proposed prototypes have been discussed. The empirical models were used to estimate the density, elastic modulus, thermal conductivity, coefficient of thermal expansion, and dielectric permittivity of the composite material, and numerical (FE) modeling is also performed for the more influencing parameters of the actuator. The results of material modeling were compared with experimental results. The carbon black particulate-filled polymer composite is developed for the investigation of density, mechanical, thermal, optical, and dielectric characteristics. The inclusion of the filler significantly improves the features of the matrix material. The density of the composite enhanced as the content of the reinforcement is increased from 5 to 25 Vol %. The elastic modulus of the composite is 57% higher than the plain matrix material. The thermal conductivity of the composite was substantially improved both numerically and experimentally. The inclusion of carbon black fillers into the PDMS leads to the reduction of the coefficient of thermal expansion. Also, the same is proved using the numerical method. The dielectric constant of the composite is improved significantly more by varying filler concentration. Analytical and numerical modeling has been carried out using commercially accessible software. Analytical findings on the deflection of the composite beam are validated with numerical modeling. The results are almost similar to each other, with a varying percentage of carbon black content and a change in the thicknesses of the layers. The bilayer composite beam is significantly more deflective than the single-layer beam. Also, by altering the temperature of the layers, the bilayer composite beam indicates considerably more deflection than the single layer. In continuing with this, the single and bilayer composite beams are tested experimentally, and it is a good agreement with numerical results. Finally, the proposed conceptual model of the photo actuator tested successfully. Attempts arexi being made in the present research to use a polymer composite beam for photo actuation and testing for the suggested prototype system. The dissertation is typically composed of empirical, numerical (FE), analytical modeling, and experimental approaches. Also, the characterization of the composite material and the efficiency of the photo actuator have been highlighted. As a result, PDMS and CB composites could be suggested for one of the photo actuator material.