Research on Reinforcement of High Temperature Vulcanized Silicone Rubber by Graphene and Multi-Walled Carbon NanO-Tubes

摘要

In this thesis we have studied HTV silicone rubber composites.Silicone rubber is reinforced by graphene and multi-walled carbon nanotubes.Although graphene and carbon nanotubes have exceptional mechanical,thermal and electrical properties but these fillers give only fraction of their original strength when mixed in polymer matrix due to poor dispersion and weak inter-facial forces between filler and polymer matrix.Numbers of different new strategies are adopted to attain better dispersion of these nano fillers within polymer matrix.Graphene oxide was prepared from graphite by using modified Hummers'method and reduced to obtain reduced graphene oxide.Addition of reduced graphene oxide in to silicone rubber by two-roll mixing technique gave poor dispersion state.New techniques,based on sol-gel,were developed to improve the degree of dispersion of reduced graphene oxide in silicone rubber.Reduced graphene oxide was dispersed in sol gel and later this semi-solid sol-gel was mixed in to silicone rubber.Reduced graphene oxide showed improved dispersion properties in silicone rubber.In another work this technique was extended to disperse multi-walled carbon nanotubes in silicone rubber.Prepared materials and composites were analyzed by SEM,TGA,XRD,FTIR and TEM.All samples were tested for mechanical and thermal properties to measure and compare the reinforcement effect with the increase and decrease of filler loading.

目录

Contents

Abstract

Notations

Chapter 1．Introduction

1．2 Reinforcement methods of silicone rubber

1．3 Graphene based polymer composites

1．4 Graphene based silicone rubber composites

1．5 Structure properties and synthesis methods for graphene

1．7 Carbon nanotubes based polymer composites

1．8 Research aim of the study and its significance

chapter 2．Reinforcement of HTV silicone rubber with reduced graphene oxide

2．3 Experimental materials and apparatus

2．4 Test methods and performance characterization

2．4．3 Field emission scanning electron microscopy(FE-SEM)

2．5 Results and discussion

2．6 Preparation of the polymer composites

2．7．2 FTIR spectrum of GO and r-GO

2．7．3 TEM of reduced graphene oxide

2．7．5 SEM characterization of fractured surfaces of r-GO／PDMS composites

2．7．6 Thermogravimetric analysis(TGA)

2．8 Conclusion

Chapter 3．Preparation of sol-gel dispersed graphene

3．3 Mechanism to entrap graphene sheets

3．5 Preparation of sol-gel encapsulated reduced graphene oxide (SG-Gn)

3．6 Test methods and performance characterization

3．7．1 Characterization of sol-gel encapsulated reduced graphene oxide(SG-Gn)

3．7．2 Scanning Electron Microscopy-Energy Dispersive Spectroscopy(SEM-EDS)

3．8 Conclusion

Chapter 4．Reinforcement of silicone rubber by sol-gel dispersed graphene

4．2．2 Experiment equipment

4．3．2 Field emission scanning electron microscopy(FE-SEM)

4．5 Results and discussion

4．5．1 Mechanical properties analysis

4．5．2 Optical Observation of Thin Film of SG-Gn／silicone rubber Composites

4．5．3 SEM analysis of fractured surfaces

4．6 Thermal properties of VMQ composites

4．7 Conclusion

Chapter 5．Reinforcement of silicone rubber with multi walled carbon nanotubes

5．3 Experimental and materials

5．3．2 Experiment equipment

5．5 Preparation of sol-gel／silicone rubber composite

5．6 Test methods and performance characterization

5．7 Result and discussion

5．7．3 Mechanical properties analysis of silicone rubber／(SG -CNTs)composites

5．7．4 SEM analysis of fracture surface of composites

5．7．5 Thermogravimetric analysis(TGA)

5．8 Condusion

Chapter 6．Conclusions and perspectives

Reference

Acknowledgements