Inorganic Nano Particles Were Synthesized By Matrix Mediated Growth Technique,

Conclusion

CHAPETER 5

CONCLUSION Inorganic nano particles were synthesized by matrix mediated growth technique, which is also known as in-situ deposition technique. It is observed that with increasing molar ratio of PEG, nano size reduces. XRD peaks become broader which is major indication of reduction in nano size. The broadening of peak may be due to vigorous mixing at molecular level. PA nanocomposites of filled with different nano sizes of CaCO 3, CaSO4, Ca3(PO4)2 and Mg(OH)2 were prepared on Twin Screw Extruder and specimen preparation was done on Injection Molding Machine.

Sizes of nano CaCO 3,

CaSO4, Ca3(PO4)2 and Mg(OH)2 were calculated by XRD and confirmed by TEM, the particle size was calculated using Scherer’s formula. Amount of filler added is very less in PA i. e. (1 to 4 wt %) shows drastic improvement in mechanical and Thermal properties, than commercial inorganic filled PA. Reduction in nanosize gives more enhancements in properties due to uniform dispersion of nano particles into PA matrix that inter relates among the polymer chains and increases degree of chain linking capacity of matrix during compounding, which transfer the heat uniformly throughout the matrix. The nanoparticles mixed in PA composites give higher intercalation with increase in filler content. Intercalation was confirmed by X-ray diffractometer. Absence of peak is major indication of exfoliation, while presence of peak shows intercalation phenomenon. The DSC results showed that nano size addition leads to increment in glass transition temperature of PA. This increment in Tg was due to Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon

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the confinement of the polymer chains within the nano particles with restriction in the mobility of polymer chains.

Also thermal stability of PA nanocomposites

increases with increase in filler content. Substantial improvements in mechanical, thermal and physical properties are observed by addition of smaller amount of nano nanofillers, which is having variety of structures. This improvement is due to the uniform dispersion of nano particles in PA, which gets intercalated and exfoliated within the polymer chains. Intercalation and agglomeration phenomenon have been confirmed using XRD grams, which the evidence for improvement in properties. Addition of Mg(OH)2 in PA shows enhancement in mechanical, thermal and physical properties. Moreover improvement in flame retarding properties of PA nanocomposite was significant. The improvement in flame retarding property was more compared to other two sizes with commercial Mg(OH)2. This improvement in flame retarding properties was due to uniform transfer of heat with uniform dispersion of nano particles into the matrix. Moreover, Mg(OH)2 is an inorganic flame retardant. When Mg(OH)2 is heated it decomposes to MgO with release of water, and at the same time process was absorb a great deal of heat to lessen the temperature on the surface of material. The extent of reinforcement has been correlated with concentration of filler in polymer. The addition of a small amount of organo-montmorillonite (1–4mass%) showed enhanced properties like mechanical parameters,flammability, hardness and rheological behavior due to uniform dispersion of OMMT in the polyamide matrix. However, OMMT also acted as lubricating agent, which reduced the

Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon

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torque and decreased viscosity along with increased elongation at break. Due to OMMT, the processing of polyamide is very easy and OMMT provides a good processing aid along with the role of the filler.

Ph.D Thesis, Mr. Shriram S. Sonawane, UDCT, North Maharashtra University, Jalgaon

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