Preparation And Property Of Polyurea/Paraffin Phase Change Microcapsules

The energy wasting phenomenon is very serious.Saving energy and developing new energy need to be solved.Energy saving is realized through the phase transition process of phase transition materials to achieve energy storage and release.In this paper,phase change microcapsules were prepared by using polyurea as wall material and low melting point paraffin as core material.The HLB of low melting point paraffin was determined.It studied that the Influence of different Kinds and amounts of emulsifier on paraffin emulsion.The effects of emulsification speed,reaction speed,core wall material ratio and reaction temperature on the phase change microcapsules were discussed.And the microcapsules prepared under different experimental conditions were subjected to infrared test,morphology test,thermal weight loss and thermal stability analysis.Finally,the best preparation conditions were determined.The hydrophilic oil balance of paraffin is10.275.Use OP-10 and Arabic gum powder to mix emulsifier.The amount of emulsifier is 1/3 of paraffin.The emulsion speed is at 1500r/min.The reaction speed is at 450r/min.The ratio of core material to shell material is 3:1.The experimental reaction occurs at 50℃.The ratio of molar of DETA to TDI is 1.3:1.DSC test analysis showed that the microcapsule temperature was 35.04℃under the optimum conditions,and the enthalpy of transformation was 103.40J/g.TG test analysis concluded that: core wax began to lose weight temperature was 150℃.The temperature at which the weight loss of paraffin wax ends was 323.5℃.The microcapsule began to lose weight at 183℃,and the final weight loss temperature was 410℃.The infrared test analysis concluded that the polyurea wall material was successfully encapsulated paraffin core material.The microcapsules of polyuria /paraffin wax are prepared under the optimum process conditions and applied to cotton and cotton-polyester cotton.In this paper,the microcapsules are arranged into two kinds of cotton cloth by immersion method and coating method.It is also used to test the hydrophilic,washable,temperature performance and thermal stability of cotton cloth.When the mass ratio of microcapsule and acrylic hydration adhesive is 1:2,the hydrophilic of the finished polyester-cotton cotton is better than that of pure cotton.Coated polyester cotton has the best water resistance.The two kinds of cotton fabrics arranged have the phase transition temperature closed to the body temperature by the two methods.Therefore,the performance of polyester cotton after finishing with microcapsule is better than that of pure cotton.The temperature performance shows that the cotton cloth with microcapsule finishing has the function of heat storage and temperature regulation.The spinning of polyvinyl alcohol solution(mass percentage of 14%)and the phase-change microcapsules(quality ratio 20:1)were made by using electrostatic spinning.The prepared phase change fiber has the best morphology.The phase transition temperature is 33.57℃.And the enthalpy of phase transition is 16.965J/g.