Mechanical Properties of SiC Sheet Reinforced Acrylic Resin

Objectives: This study aimed to evaluate the mechanical properties of SiC sheet embedded acrylic resin and silanation effect of SiC sheet.
Methods: To prepare experimental SiC sheet reinforced acrylic resins, a commercially available acrylic resin for denture (Acron, GC, Japan), a commercially available silan coupling agent (PZ primer, Sun medical, Japan), and a SiC sheet (Nicalon, NGS Advanced Fibers Inc., Japan) were used. Specimens were prepared according to the ISO 20795-1. The size of rectangular shaped specimen was 64x10x3.3 mm, the polymerization method was flasking, and the polymerization condition was at 70°C for 12 h. The group of specimens were divided into 3 groups as followings. 1) acrylic resin as control, 2) acrylic resin containing the SiC sheet, and 3) acrylic resin containing the SiC sheet with silanation according to manufacturer’s instructions. These specimens were stored at 37±1°C water for 50±2 h after the polymerization. The mechanical properties were evaluated by three-point bending test measured by universal testing machine (AUTOGRAPH AG-1000E, Shimadzu, Japan), cross head speed 5.0 mm/min, span 50 mm, according to the ISO 20795-1. All data were statistically analyzed with Student’s t test (P<0.05).
Results: Flexural strength of 1), 2), and 3) were 88.6±10.8, 154.9±28.6, and 225.7±13.5 MPa respectively and elastic modulus were 2.7±0.1，6.0±1.5, and 5.1±0.2 GPa, respectively. Flexural strength of 3) was significantly higher than other groups, though there was no significant difference of elastic modulus among the groups.
Conclusions: These results suggested that SiC sheet embedded acrylic resin and silanation of SiC sheet improved the flexural strength of the acrylic resin.