Use acrylic organic rigid fillers to increase toughness. When the acrylic material is stretched, the difference between the matrix and the dispersed spheres causes the material matrix to exert a stronger pressure on the rigid organic filler, thereby transforming its toughness, and the rigid organic filler particles undergo "cold flow" deformation and absorption. Plastic deformation can improve the toughness of the material.www.611676.com/11x17-acrylic-sign-holder/