Research On Superficial Modification Of Calcium Hydroxide And Its Application

The calcium hydroxide is difficult to be achieved to high homogenous and high dispersity in the procedure of shaping,which causes the worse property of materials, due to its character of instability,easy to react with CO₂ in the air,and poor compatibility with macromolecule materials as plastics and rubber.In order to solve these problems,industrial grade CaO was used in this paper,isopropanol pentaerythritol,Bisphenol AF solution with a small amount of ethanol was added respectively when people Synthesize calcium hydroxide,and superficial modified calcium hydroxide with organic reagent was Successfully Synthesized,synthesis condition and application were researched also,The results show that:The best conditions of the calcium hydroxide modified by isopropanol:the synthesis of aqueous isopropyl alcohol concentration is 5.5%wt,the temperature of reaction is 75℃,and the time of reaction is 1.5h,the average diameter of modified calcium hydroxide prepared is about 6-8μm under the best condition,Sedimentation volume is 7.0ml in the benzene.The best conditions of the calcium hydroxide modified by pentaerythritol: pentaerythritol dosage is 1.2g,the temperature of reaction is 78℃,and the time of reaction is 1.5h.,the average diameter of modified calcium hydroxide prepared is about 5-6μm under the best condition,Sedimentation volume is 6.8ml in the benzene.The best conditions of the calcium hydroxide modified by bisphenol AF: bisphenol AF dosage is 0.5g,the temperature of reaction is 75℃,and the time of reaction is 2h.,the average diameter of modified calcium hydroxide prepared is about 2-4μm under the best condition,Sedimentation volume is 8.0ml in the benzene.IR spectrum analysis and XRD analysis show that the synthesis product is the calcium hydroxide,the organic reagent and the calcium hydroxide is not the simple mix,but they unify through the strong static electricity function.and form the gable function together,we may know that decomposition temperature of the calcium hydroxide modified by different organic reagent has not small difference through the heat-stable analysis,Which has achieved 380℃,So they may be used for the chemical additive of high polymer PVC.The calcium hydroxide modified by pentaerythritol and isopropyl alcohol respectly can enhance effectively thethermal stability of PVC,The calcium hydroxide modified by bisphenol AF can not enhances the thermal stability of PVC obviously. Add the same component calcium hydroxide modified by pentaerythritol and isopropyl alcohol respectly the latter's heat-stable time excels in above obviously the former 20 minutes,and the recruitment is bigger,heat-stable time is longer.Mechanical properties of PVC will drop slowly when the quantity of the calcium hydroxide modified by pentaerythritol,isopropyl alcohol and bisphenol AF respectly increase,when the recruitment are few(for example is 5g),the PVC mechanical properties drop not obviously.Test showed that the few component calcium hydroxide modified by pentaerythritol and isopropyl alcohol can solve thermal stability of PVC,and mechanical properties of PVC drop not obviously have certain application value.Besides,superficial modified mechanism of calcium hydroxide and the heat stable action mechanism of its to PVC were also studied.