In order to replace "carbon" with "silicon" for synthetic leather coating materials, polydimethylsiloxane (PDMS) polymer coatings were prepared by in-situ polymerization reaction under thermal induction using divinyl-terminated polydimethylsiloxane (ViPDMSVi), polymethylhydrosiloxane (PMHS), divinyl-terminated polymethylvinylsiloxane (ViPMVSVi), and fume silica as the main raw materials. The properties of PDMS polymer coatings were characterized by mechanical properties, DSC, flexural resistance, abrasion resistance, hydrophobic and antifouling tests, and the effects of ViPDMSVi, PMHS active hydrogen, double bond to active hydrogen molar ratio, ViPMVSVi, and fume silica on the tensile strength, elongation at break and hardness of PDMS polymer coatings were investigated. The results show that the mechanical properties of PDMS polymer coatings were most significantly improved when the mass fractions of ViPMVSVi and fume silica were 7% and 40%, respectively. The tensile strength of the PDMS polymer coating produced under the optimized conditions was 5.96 MPa and the elongation at break was 481%. Synthetic leather coatings exhibit excellent low-temperature flexing, abrasion resistance, hydrophobicity, and anti-fouling properties.