The Mechanical and Rheological Properties of Polydimethylsiloxane Elastomers Prepared by a Hydrosilylation Reaction

Abstract

Polydimethylsiloxane (PDMS) elastomers are widely used in biomedical, microfluidic, and flexible electronic applications due to their tunable mechanical properties. Modifying PDMS through hydrosilylation offers a controlled approach to tailor elasticity and network structure. PDMS elastomers were synthesized via a hydrosilylation reaction, and their mechanical and rheological properties were compared with the commercial Sylgard 184 formulation. Sylgard 184 PDMS elastomers exhibit elastic moduli ranging from 0.63 to 2.46 MPa, depending on the base-to-agent ratio, as calculated from compression and tensile testing. PDMS elastomers prepared by hydrosilylation show elastic moduli varying between 0.67 and 1.32 MPa, depending on the base chain length and the mole ratio of base to crosslinker, as calculated under similar testing conditions. In contrast, moduli calculated from rheology storage modulus data are significantly lower than those from mechanical tests. The moduli of Sylgard 184 samples are between 0.32 and 0.80 MPa, whereas rheological data for the hydrosilylation formulations yield moduli that range from 0.26 to 0.47 MPa. Although the modulus results using a hydrosilylation reaction are lower than those of the commercial polymer, they remain comparable, so the hydrosilylation reaction provides an alternative elastomer formulation with the advantage of greater control over its mechanical and rheological properties.