Preparation and characterization of thermoplastic materials for invisible orthodontics

• Published in: Dental Materials Journal Vol. 30; no. 6; pp. 954 - 959
• Main Authors: ZHANG, Ning, BAI, Yuxing, DING, Xuejia, ZHANG, Yu
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Society for Dental Materials and Devices 2011; Japanese Society for Dental Materials and Devices
• Subjects: Blend; Blending; Dental Materials - chemistry; Dental Stress Analysis - methods; Dentistry; Elongation; Humans; Invisible orthodontics; Materials Testing; Mechanical properties; Modification; Orthodontic Retainers; Orthodontics - methods; Polycarbonates; Polycarboxylate Cement - chemistry; Polyethylene Glycols - chemistry; Polyethylene Terephthalates - chemistry; Polyurethanes - chemistry; Stress relaxation; Tear strength; Thermoplastic materials; Thermoplastic resins; Urethane thermoplastic elastomers
• ISSN: 0287-4547; 1881-1361
• DOI: 10.4012/dmj.2011-120

PETG/PC/TPU polymer blend was prepared by mechanical blending. The mechanical properties of modified PETG/PC/TPU blend were characterized using a universal testing machine, and results were compared against two commercial thermoplastic products —Erkodur and Biolon. Blending modification improved the properties of PETG/PC/TPU. When blending ratio (wt%) was 70/10/20, PETG/PC/TPU exhibited optimal mechanical properties which exceeded those of Erkodur and Biolon. Tear strength was 50.23 MPa and elongation at break was 155.99%. Stress relaxation rate was 0.0136 N/s after 1 hour, which was significantly slower than Erkodur and Biolon (p<0.05). Water absorption rate was 0.57% after 2 weeks, which was significantly lower than Erkodur and Biolon (p<0.05).