Mechanical Analysis of Polycarbonate/Polysiloxane Block Copolymers and Blends

• Main Author: Zhou, Tingting
• Format: Others
• Published: North Dakota State University 2017
• Online Access: https://hdl.handle.net/10365/26869

Polydimethylsiloxane (PDMS) can be used to react with polycarbonate (PC) to generate PC-PDMS multiblock copolymers and PC/PC-PDMS-PC triblock blends to overcome the notch sensitivity of PC while maintaining its transparency. It was found in this study that PDMS can act as a rubber particle to absorb energy and promote multicrazing. As a result, the incorporation of PDMS can increase PC's toughness. Meanwhile, high optical clarity can be observed even at 62 wt% PDMS in the multiblock copolymers with uniform morphology. However, PC/PC-PDMS-PC triblock blends damage PC's transparency and become opaque due to the phase separation. Furthermore, compared to compression molding, injection molding introduces shear due to the decrease of the area at the nozzle, which leads to the orientation of polymer chains and, subsequently, better properties of specimens.