Nano Double Hydroxides In The Preparation And Application Performance, In Pvc

The main objective of this thesis is to study the flame retarding properties of Layered Double Hydroxides(LDH). By synthesizing nano-scale LDH, characterizing its structure as well as testing thermal stability and flame retarding properties of PVC-LDH composite, we studied the relationship between special layered structure of LDH and thermal stability and flame retarding properties which were showed by LDH in PVC. We tried to find the mechanism of thermal stability and flame retarding effect of LDH. It was showed that LDH had good effect in terms of flame retarding, smoke suppressing and heat co-stabilizing with organic stannum.By characterizing the particle size, size distribution and shape of LDH, we found that LDH was a nano-materials with regular crystal structure. Having compared the effect of different surface active agent, we selected a proper agent to modify LDH and improve the compatibility between LDH and PVC. So effective filling was realized.The thermal decomposition kinetics of LDH was studied by means of thermogravimetry(TG). We worked out the activation energy, the reaction orders as well as the frequency factor of the thermal decomposition by binary regression. Through measuring oxygen index and smoke density, the flame retarding and smoke suppressing properties were studied from different aspects, such as structure and composition of LDH, nanoscale effect, endothermal process and releasing of CO2 and H2O in the process of decomposition.We investigated heat stabilizing effect of LDH upon PVC through dynamic and static experiment. It was found that LDH and organic stannum gave an obvious synergy in term of thermal stability.The experimental results showed that LDH is a heat stabilizer, fire retardant and favorable smoke suppressant.layered double hydroxides; PVC; flame retardant; heat stabilizer;smoke suppressant...