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TITLE
DEDICATION
CERTIFICATE-1
CERTIFICATE-2
DECLARATION
GLOSSARY OF TERMS
ACKNOWLEDGEMENT
CONTENTS
1. Introduction
I. I. Polymer blends.
Table I.I Principal properties claimed in polymer blend patents
Fig. 1.1: Schematic representation of the steps to be taken when developing polymer blends
1.2. Polymer blends: Miscibility and Compatibility.
Table 1.2: Examples of intermolecular interactions in polymer blends ofvarying degrees of miscibility
1.3. Compatibilisation in blends
Fig. 1.2: Summary of the factors contributing to end-use properties in melt compounded blends
1. 4. Method of polymer blending.
1.5. Thermoplastic elastomers
Fig. 1.6: Digrammatic morphology of a thermoplastic elastomer
1.6. Dynamic vulcanization.
Fig. 1.7: Illustrative idealization of phase mrphologies of TPE Mendsbefore and after dynamic vulcanization.
1 7. Relevance of styrenic plastics-nitrile rubber TPEs.
1.8 Scope of the work .
References.
2. Experimental Procedure
2. 1. Characterization techniques used in this work .
2.2. Experimental Details.
2.2.1.Materials.
Table 2.1. Details of materials used
2.2.2.Blend preparation.
2.2.3.Morphological studies.
2.2.4.Molecular weight determination.
2.2.5.Dilute solution properties.
2.2.6.Mechanical testing.
2.2.7.Melt-rheological measurements.
2.2.8.Fourier-transformed infra-red spectroscopy
2.2.9.Thermal characterization.
2.2.10.Swelling studies.
References.
3. Compatibility Studies of PS / NBR, SAN / NBR & ABS / NBR Binary Systems
3.1Compatibility of the blends in the solid state.
3.1.1.Determination of solubility parameter.
3.1.2.Polymer-polymer interaction in the blends.
3.1.3.Spectroscopic evidence in the blends.
3.2 Compatibility of the NBR based blends in solution.
3.2.1. Dilute Solution Viscosity Theories for Compatibility Studiesof Polymer Blends
3.2.2. Additivity Concept of Intrinsic Viscosity for Assessing Miscibility
3.2.3. Specific Viscosity as given by Catsiff & Hewetts Model
3.2.4. Krigbaum and Wall Parameter,
3.2.5. Dilute Solution Density Measurements
References.
4. Polystyrene / Acrylonitrile-Butadiene Rubber Binary Blends
4.1. State of compatibility.
4.2. Optimization of mixing parameters
4.3. Morphology of the blends.
Fig.4 6: Scanning electron micrographs of melt-mixed PS/NBR blends; PS30 (a), PS50 (b) and PS70 (c) .
Fig.4 7. Optical micrographs of solution-casted PS/NBR blends; PS30 (a), RS50 (b), and PS70 (c)
4.4. Processing characteristics.
4.5. Mechanical properties.
4.6. Rheological properties.
4.6.1Melt rheology of blends.
4.6.2.Melt elasticity of blends.
4.6.2.a Extrudate Swell (or Die-swell)
4.6.2.b. Principal Normal Stress Difference
4.6.2.c. Recoverable Elastic Shear Strain
4.6.2.c. Elastic Shear Modulus
4.6.3. Melt Fracture
Fig.4.3 1: Scanning electron micrographs of the extrudate surface of PS30 (a) PS5O (b), and PS70 (c); extruded at 139 /s. (Mag: 50x) .
4.6.3.b. Effect of Shear Rate
Fig.4.32: Scanning electron micrographs of the PS50 blend extrudate, extruded at two different shear rates, viz. (a) 69 /s and (b) 278 /s.
4.6.4.Effect of processing on state of dispersion.
Fig. (a) 4.33: Scanning electron micrographs of the outer regions of the PS/NBR blend extrudates, extruded at y =I 39/s. (a) PS30, (b) PS50, and (c) PS70 blend (Mag 800 x)
Fig.4.34: Scanning electron micrographs of the core regions of the PS/NBR blend extrudates, extruded at y =I39 /s. (a) PS30, (b) PS50, and (c) PS70 blend. (Mag: 800x)
Fig.4.35: Scanning electron micrographs of PS50 blend extrudates, extruded at y =69 /s. (a) core region, (b) outer region. (Mag: 800x)
Fig.4.36: Scanning electron micrographs of PSso blend extrudates, extruded at y -278 Is. (a) core region, (b) outer region. (Mag: 800x)
4.7. Thermal properties.
References.
5. Poly (styrene-co-acrylonitrile) I Acrylonitrile-Butadiene Rubber Binary Blends
5.1. Brabender rheometry.
5.2. Morphology.
Fig.5.3: Scanning electron micrographa of SAN/NBR blends; SAN30 (a), SAN (b), and SAN70 (c)
Fig.5.4: Optical micrographs of solution-casted SAN/NBR blends; SAN30 (a), SAN50 (b), and SAN70 (c)
5.3. Mechanical properties.
5.4. Rheological properties.
5.5. Thermal properties.
References.
6. Poly (acrylonitrile-co-butadiene-co-styrene) / Acrylonitrile-Butadiene Rubber Blends
6.2. Rheological properties.
6.3. Melt elasticity.
6.4. Thermal properties.
References.
7. Compatibilisation of heterogeneous PS / NBR blends by the addition of SAN and ABS copolymers
7.1. Compatibilisation using SAN copolymer.
Fig. 7.1: Schematic mechanism illustrating the interfacial activity of SAN copolymer in PS/NBR blends.
7.1.1.Morphology.
Fig.7.3: Optical micrographs of PS/NBR 30170 blend with 2 wt.% SAN.
Domain size distributions
7.1.2.Brabender torque rheometry.
7.1.3.Morphology of the melt-mixed blends.
7.1.4.Tensile properties.
Fig.7.10. Scanning electron micrographs of melt-mixed PS/NBR blends compatibilised with SAN; (a) PS50 SAN 2wt % (b) PS50 SAN 10wt.%
7.1.5.Tear properties and Hardness.
7.1.6.Impact properties.
7.1.7.Effect of PS / NBR ratio on the mechanical properties.
7.1.8.Effect of mixing protocol.
Fig.7.20: Speculative model representing the behaviour of compatibiliser having different mode of mixing.
7.1.9.Melt rheology of compatibilised Blend.
7.1.10.Melt fracture.
Fig.7.29: Scanning electron micrographs of the extrudate surface of PS/NBR 50/50 blends compatibilised with SAN;
7.1.11 State of dispersion in processed blends.
Fig.4.30. Scanning electron micrographs of PS/NBR 50/50 (compatibilised with 2 wt % SAN) blend extrudates, extruded at y = 139 is. (a) core region, (b) outer region. (Mag: 800x)
7.1.12.Thermal properties.
7.2 Compatibilisation using ABS copolymer.
7.2.1.Morphology.
Fig. 7.37: Schematic mechanism illustrating the interfacial activity of ABS terpolymer in PS/NBR blends.
Fig.7.38: Optical micrographs of solution-casted PS/NBR blends compatibilised with ABS; (a) PS30 ABS 2wt.%, (b) PSSO ABS 2wt.% and (c) PS70 AJ3S 2wt.%
Fig.7.39: Scanning electron micrographs of melt-mixed PS/NBR blends compatibilised with ABS; (a) PS50 ABS 2wt.%, (b) PS50 ABS 5wt.%.
7.2.2.Mechanical properties.
7.2.3.Melt-flow properties
7.2.4.Thermal properties.
7.3 SAN and ABS as compatibilisers for PS / NBR system: a comparison
7.4 Compatibilising effect of SAN and ABS: mechanism.
References.
8. Dynamic vulcanization of the blends
8.1. Effect of the cross-linking system.
Fig. 8.4: Scanning electron micrographs of dynamically vulcanizedPSINBR 50150 blends;
8.2. Effect of rubber / plastic ratio on dynamic vulcanization.
Fig. 8.5: Schematic representation of dynamically PS/NBR blends.
8.3. Effect of dynamic vulcanization in presence of a compatibiliser
Fig 8.6. Scanning electron micrographs of PS/NBR 50/50 blends dynamically vulcanized in presence of a compatibiliser.
Fig. 8.7: Scanning electron micrographs of PS/NBR blends
8.4. Thermal properties of dynamically vulcanized blends.
8.5: Swelling behaviour of dynamically vulcanized blends.
References.
9. Reprocessability of the blends
9.1: Effect of reprocessing on morphology.
9.2: Effect of reprocessing on structural changes.
Fig. Scanning electron micrographs of reprocessed PS/NBR 50/50 blend; zero time reprocessed (a), one time reprocessed (b); two time reprocessed (c)
9.3: Effect of reprocessing on molecular weight.
9.4: Effect of reprocessing on melt-flow properties.
Fig.9.4 Scanning electron micrographs of the extrudate surface of reprocessed PS/NBR 50/50 blend; zero time reprocessed (a), one time reprocessed (b), two time reprocessed (c)
9.5: Effect of reprocessing on mechanical properties.
References.
10. Conclusion
10.1. Conclusion.
10.2. Scope of future work.
List of Publications in International Journals
Curriculum Vitae
APPENDIX