Effect of Modified Polyorganosiloxane on Physical Properties of Acrylate Hard Coating

Rubber toughened acrylate was investigated as a protective hard coating material for plastic film to improve the flexibility while maintaining intrinsic hardness of acrylate. Polyorganosiloxane(POS) was chosen as a rubber phase to apply thin acrylate coating. Poly(methyl-vinyl) siloxane (PMVS) and modified polydimethylsiloxan (PDMS) having urethane and urea linkage were synthesized and also introduced as a rubber toughening phase. Increasing PMVS content in acrylate caused the increase of flexibility as well as hardness. However, the printability was dramatically dropped due to the increase of hydrophilicity on the coating surface by PMVS. Modified PDMSs having urethane and urea linkage in main chain enhanced the flexibility and hardness similar to PMVS while maintaining hydrophobicity which affected the printability in the coating surface. In addition, it was found that PMVS and modified PDMSs did not affect the optical transmittance in acrylate coating.